Lindsay MachanDepartment of Radiology, Vancouver Hospitaland Health Sciences CenterVancouver, Canada

The powerful advantages conferred to thepatient by fluoroscopically guided minimallyinvasive procedures are well known to all inter-ventional radiologists. However, in many casesthe longevity of interventional procedures is, oris perceived to be, less in comparison withmajor surgical procedures. Thus most interven-tional procedures at present can be consideredtemporizing procedures. Adding pharmacolog-ic or biological activity to a device ("drug -device combinations") can potentially improvethe efficacy and longevity of minimally invasiveprocedures. In some cases procedures whichare at present palliative could even becomecurative. In addition to extending the numberof patients to whom they can be applied, theprocedures are made even more attractive topatients and referring clinicians and moreacceptable to paying agencies.

Drug - device combinations are not just beingapplied to minimally invasive procedures, theyare being developed for virtually every area ofmedicine1. These include antimicrobial woundcare products, bone graft substitutes, antibioticbone cements, antimicrobial catheters, photo-dynamic therapy, pastes and sprays for preven-tion of post surgical adhesions, wound closureenhancers and regional gene therapies, amongmany others. The global market for drug-devicecombinations was approximately $5.4 billion in2004 and is expected to rise at an averageannual growth rate of 13.6% to $11.5 billion in2010 2.

A number of biologically active devices havebeen developed for minimally invasive therapy.The most well known of these are drug elutingstents3, but a far from complete list alsoincludes drug releasing embolic particles, coat-

ed embolic coils, targeted embolization agents,pharmacologic agents to optimize ablative pro-cedures , ultrasound and energy assistedthrombolysis, implantable venous valves, coat-ed stent grafts, anti-infective central lines, andself sealing biopsy devices. The range anddiversity of biological activities associated withthese devices is breathtaking. Coating a stentgraft with a sclerosant or substance whichinduces a mural reaction might improve long-term outcomes by addressing in particularendoleaks, device migration and disarticula-tion. Using focused energy such as ultrasoundor heat allows systemically subtherapeuticdoses of otherwise toxic drugs to be releasedat therapeutic concentrations at the site of apercutaneous intervention to accentuate tissueablation and potentially prevent local recur-rence. Other materials such as porcine intestin-al submucosal can act both as a scaffold anddeliver cytokines for controlled regional tissuegrowth or replacement, or building upon thesuccess of islet cell transplantation, exogenouscellular implants are being delivered by mini-mally invasive image guidance.

Drug eluting stents have been described as atransforming technology. They have decreasedthe number of referrals to cardiac surgeons aswell changing the types of patients beingreferred4. They have also transformed the busi-ness of medical devices and the science by vali-dating the concept that adding biologicalactivity to a medical device can improve itsperformance, and by showing that it is possibleto have such a device approved for clinical usewhile being financially viable. These hurdleshad to be overcome before postulated thera-pies made possible through the merger ofphysical, biological and medical advancesoccurring over the past decade could bereduced to practice.

Multiple lessons have already been learnedabout the use of drug eluting stents outsidethe coronary circulation. It is clear that theremarkable success of drug coated balloonexpandable stents in mid-sized coronary arter-ies cannot be repeated by merely applying thesame drugs in the same manner in other arteri-

al beds, and that considerable further researchis necessary before their role in peripheral vas-cular and non-vascular disease can be defined.The SIROCCO trial of sirolimus coated self-expanding stents in the SFA taught us that thesame profound inhibition of intimal hyperpla-sia can be achieved as in coronary arteries at 6months. Nevertheless, a durable effect is quick-ly lost because of the very different milieu ofthe superficial femoral artery5. In the GREATtrial of balloon-expanded sirolimus stents wesaw that while a reduction of restenosis wasachieved (albeit less marked than in other drugeluting stent trials), this did not positivelyimpact the clinical outcome of the patient6. Forthe first time in endovascular stenting, we havea potentially commonly used technologywhich is so expensive to develop and test withthe rigor required of pharmaceutical agents,that even if efficacy can be demonstrated inpreclinical testing, economics may preventmany applications from becoming clinical reality.

Drug -device combinations have a much morecomplex regulatory pathway in comparisonwith simple devices (Table 1). This presentsunique challenges for device companies, notthe least of which is that most device compa-nies may not have the financial resources orskill sets to develop a given device from con-cept to approved product. One of the featuresof Interventional Radiology which makes it soattractive to its practitioners is the diversenumber of methods of treatment we perform.This results in many individual procedures,many of which do not generate markets of suf-ficient size to allow companies to recover theinvestment necessary to develop an approvedproduct. This may steer companies to chooseto develop drug - device products for otherspecialties, particularly those who embracenew technologies and exploit practice oppor-tunities enthusiastically.

In order to fully explore the potential of thesebiologically active therapies, more compleximaging will be required7. To best assess theendpoint and the effect of the therapy as wellas distribution of all injected materials andtheir breakdown products will require accurate

Drugs and Devices

Enjoy an exquisite dinner accompanied by an outstanding entertainment programme at thefund raising party in aid of the CIRSE Foundation. The yearly event has become one of thesocial highlights of our meetings, providing the perfect opportunity to get together with oldfriends and meet new colleagues.

This year's Foundation Party will take place at Villa Miani, a wonderful mansion in Victorianstyle on the slopes of Monte Mario. It is immersed in a beautifully kept garden and offers aunique panorama overlooking the city of Rome all the way to St. Peter's Cathedral.

If you are interested in joining us for the Foundation Party, please contact the Kuoni booth inthe registration area. Since the number of tickets is limited, we recommend early booking.

IRnewscongress

CIRSE 2006 - RomeMonday, September 11, 2006

The CIRSE Roesch Lecture, established in 2003,honours Professor Josef Rösch, whose award-winning research work spans more than 50years, covering a wide range of Vascular andInterventional Radiology. Two of his mostnotable achievements are the development ofthe TIPS technique in 1969 and the introduc-tion of embolization into the treatment of gas-trointestinal bleeding in 1971. To this day,Professor Rösch continues his work on thedevelopment of new techniques and devicesfor interventional treatment.

This year's Roesch Lecture will be given by aphysician whose vision for IR is no less promis-ing: Dr. Lindsay Machan. The co-founder ofAngiotech Pharmaceuticals and consultant tothe scientific advisory board of multiple med-ical device companies will speak about "Drugsand Devices - Challenges and Opportunities forInterventional Radiology".

Josef Roesch LectureMonday, September 11, 14:30-15:15, Aula Magna

anatomic and functional information. At pres-ent, for most institutions this implies perform-ing delayed contrast-enhanced cross-sectionalimaging or possibly PET scanning. To optimisethese therapies, it would seem that a real-timesolution is necessary. There are multiple tech-nologies that may accomplish this. One of themost promising for interventional proceduresis fusion imaging. Image fusion allows data setsfrom one cross-sectional modality, such as MR,to be simultaneously displayed with simplereal-time imaging such as fluoroscopy or ultra-sound or pre and post interventional imagingto be simultaneously displayed8. Most of thesewill require imaging knowledge and skillswhich play to the strengths of radiologists.

SummaryA spectacular array of drug - device combina-tions have appeared on the horizon promisingto improve and expand existing interventionalprocedures and further titillate the ever grow-ing patient desire for minimally invasive treat-ments. Regulatory and financial issues willimpact their development and distribution to afar greater extent than IRs have seen in thepast with non-coated devices. InterventionalRadiology meetings increasingly includegloomy sessions lamenting loss of marketshare due to a perceived lack of patient careskill sets. Skills which radiologists do possessand can exploit to advantage over most clini-cians is the ability to interpret the advancedimaging, which will be necessary - initially aspart of a tortuous regulatory process and laterto use these devices to their full capability. Likeany advantage, if not exploited, it will prove tobe temporary.

References:1. Wu P, Grainger DW. Drug/device combinations for local drug

therapies and infection prophylaxis. Biomaterials. 2006;27:2450-67.

2. Report RB-205 Drug Device Combinations, BusinessCommunications Company, Inc. (www.bccresearch.com).

3. Ong A, Serruys P. Technology Insight: an overview of research indrug-eluting stents. Nat Clin Pract Cardiovasc Med. 2005;2:647-58.

4. Liddicoat J, De La Torre R, HoK et al. Initial Impact of Drug-ElutingStents on Coronary Artery Bypass Graft Surgery. Ann Thorac Surg2006;81:1239-1242.

5. Duda SH, Bosiers M, Lammer J, et al. Sirolimus-eluting versus barenitinol stent for obstructive superficial femoral artery disease: theSIROCCO II trial. J Vasc Interv Radiol. 2005;16:331-338.

6. Rabbia C. The Palmaz Genesis Peripheral Stainless Steel BalloonExpandable Stent in REnal Artery Treatment (GREAT ) trial.Presented at 2005 Cardiovascular and Interventional RadiologySociety of Europe Annual Meeting, Nice, France.

7. Daldrup-Link H, Simon G, Brasch R. Imaging of tumor angiogene-sis: current approaches and future prospects. Curr Pharm Des.2006;12:2661-72.

8. Fujioka C, Horiguchi J, Ishifuro M, et al. A feasibility study: evalua-tion of radiofrequency ablation therapy to hepatocellular carcino-ma using image registration of preoperative and postoperativeCT. Acad Radiol. 2006;13:986-94.

Challenges and Opportunities for Interventional Radiology

Table 1: Regulatory differences between devicesand drugs

C RSECardiovascular and Interventional Radiological Society of Europe

Tuesday, September 12, 20:00 Last chance to buy your tickets

CIRSE Foundation Party

Special Edition / CIRSE 2006 - Rome

2 The Future of IR Suites Monday, September 11, 2006

Recent developments in imaging technologyhave enabled new procedural opportunities inInterventional Radiology. During the first 10 to15 years of the specialty's emergence, therewas a rapid growth in catheter-based diagnos-tic angiography and non-vascular percuta-neous interventions. Early vascular interven-tions, although less frequent in terms of casevolume, included embolization procedures,often to address gastrointestinal hemorrhage.Subsequently, during the next period of spe-cialty development (1980 to 2000), a dramaticexpansion in the volume and spectrum ofendovascular interventions was experienced. Inconcert with this trend in the early 1990's, newnon-invasive vascular diagnostic modalities,including spiral CT and MR angiography, burstonto the scene.

Consequently, a distinct change occurred inthe relative proportions of conventional diag-nostic arteriograms and catheter-based vascu-lar interventions performed. This shift to anexpanding volume of endovascular therapy

and a diminishing frequency of catheterangiography in favor of non-invasive vascularimaging continues. However, in the last fewyears it is increasingly clear that IR is poised toenter an interesting new procedural phase thatwill combine both diagnostic (non-invasive andcatheter-based evaluations) and interventionalvascular encounters in one physical location orsuite. The development of multi-modalityapproaches that fuse the diagnosis and treat-ment of patients into imaging algorithms at asingle site provides new potential opportuni-ties for improving operational efficiencies.

The combination of MR and conventional fluo-roscopy and angiography; integration of CTand angiographic units; refinement of high-speed rotational angiography and the emer-gence of dual energy source CT and fluo-roscopy have created a new range of proce-dures that are being actively explored. Indeed,the current challenge for imaging equipmentmanufacturers and clinicians is no longer oneof identifying new imaging technology, butdefining the operational processes that opti-mally utilize combinations of imaging modali-ties to deliver incremental benefits to healthsystems and patients by more efficiently, safely,

and economically evaluating and treating theirdisease. In this regard, initial experience hasexamined a number of multi-modality examsequences that demonstrate promise andeagerly await further investigation to betterunderstand the potential value.

The future also may include a marriage of inter-vention with new diagnostic studies capable ofenhancing tissue differentiation (dual sourceCT) and evaluating tissue function (PET/CT andMR/PET). Currently, investigators are just begin-ning to explore the surface of what new oppor-tunities will soon exist to increase proceduralefficiency, accuracy, convenience, safety, speed,comfort, and ultimately, a better overall experi-ence for patients than now possible with a tra-ditional management sequence split betweenwork-up and treatment stages separated intime, place, etc.

Simple initial pilot studies at a variety of cen-ters around the world have provided proofs ofprinciple validation for some of the novelopportunities that differentiate this concept ofblending multi-modality diagnostic and thera-peutic exams into a single encounter at a singlelocus. Examples include rotational angiography

The IR Suite of the Future: How many tools can we integrate?

for improved real-time planning of inferiorvena cava filter insertion; MRA of lower extrem-ity run-off immediately prior to an expectedendovascular intervention; MRA via a superiormesenteric artery catheter to evaluate hepaticarterial supply in conjunction with chemoem-bolization of liver tumors (Figure 1); MR guid-ance for TIPS creation with integrated fluoro-scopic monitoring of stent placement 1, highspeed rotational angiography with three-dimensional multi-planar reconstructions tofacilitate a spectrum of endovascular and non-vascular interventions, etc.

It is inevitable that widespread further experi-ence will develop a broader scope of highimpact applications while identifying thosethat deliver objective value to patient care.Indeed, the challenge over the next few yearswill be in better defining the optimal opera-tional role of these multi-modality combinationprocesses in the IR practice.

References:1.Kee ST, Ganguly A, Daniel BL, Wen Z, Butts K, Shimikawa A, Pelc NJ,

Fahrig R, Dake MD. MR-guided transjugular intrahepatic portosys-temic shunt creation with use of a hybrid radiography/MR system.JVIR. 2005 Feb;16(2 Pt 1):227-34.

IR/OR Suite of the FutureSpecial Session 31Monday, September 11, 10:15-11:30Room F

Michael D. DakeProfessor of Radiology, Medicine (PulmonaryDisease), Surgery;Chairman of the Department of Radiology, The Harrison Medical Teaching Professor ofRadiology,University of Virginia Health System

Figure 1: MR-guided puncture of portal vein during TIPS procedureFigure 1a: Gradient recalled echo (GRE) MR image of needle entering the portal vein of a patient

undergoing TIPS for portal hypertension and bleeding varicesFigure 1b: Steady state free precession (SSRE) MR image of needle puncturing the portal vein during TIPS

A B

Cardiovascular and Interventional Radiological Society of Europe

3ER vs. AAAIRnewscongress

C RSECardiovascular and Interventional Radiological Society of Europe

More than fifteen years have passed since theoriginal description of endovascular repair (ER)for aortic aneurysms in very unfit patients(Parodi, Ann Vasc Surg, 1991). During this timegreat technological advances have been madeboth in terms of the devices used in ER and inthe imaging assessment of aortic anatomy andpathology. However, as has been the case dur-ing the introductory phase of many new proce-dures, the gathering of meaningful "level 1"evidence in support of the new technique haslagged behind clinical practice. Fortunately, theEUROSTAR registry was started soon after theintroduction of ER in Europe and stimulatedpublications that have demonstrated the gen-eral level of safety and efficacy of the tech-nique. None the less, any complacency on thepart of enthusiasts for ER has been dispelled byregistry evidence of the rate of failure of theearly endovascular devices and a persistentsmall incidence of AAA rupture (Harris, J VascSurg, 2000).

RANDOMISED TRIALSThere are several large national multi-centreRCTs of ER versus open repair currently ongo-ing in Europe and North America. The earlyoutcomes of the 2 first European trials werepublished in 2004, the UK EVAR trials in theLancet and the Dutch DREAM trial in the NewEngland Journal of Medicine. These studiesclearly demonstrated the anticipated reduc-tions in peri-operative mortality, hospital stayand (transiently) in health related quality of lifemeasures. In fact, the gain in terms ofimproved peri-operative mortality was actuallyvery large, a three fold reduction in the ERgroups compared to the open surgical controlsin both RCTs. The DREAM trial result did notreach statistical significance, almost certainlybecause the trial groups were too small. Mostcentres practising ER within the NHS in the UKcontinued to randomise cases after the appear-ance of the early results, or at least continuedto perform cases and submit to the registries.

MID-TERM RESULTSThe follow-up data from these two trialsappeared in the same journals in June 2005.After the passage of a further 15 months, thestatus of ER as a mainstream treatment actuallyappears untouched now. While this would beno surprise to the stent-graft enthusiast, themid-term results have actually stimulated greatcontroversy. Both trials showed that the earlymortality gain in the ER groups were not asso-ciated with any significant change in all-causemortality at 2 years (10% in both study groupsof the DREAM trial) and 4 years (28% across theEVAR trial groups). There was a greater inci-dence of 'complications' during the follow-upof ER, but many of these did not require re-intervention and there was no additional mor-tality.

It has been persistently argued that theabsence of a reduction in all cause mortality inthe ER group at 3 years, whilst the aneurysmrelated mortality remained 3% less, indicatesthat ER has been an expensive failure, becauseno additional lives appear to have been saved.This argument overlooks the fact that thepatient can be offered a technique associatedwith a risk of peri-operative death that is 3times lower than that of the conventional,open operation. After all, the aim of AAA repairis to reduce the future chances of an aneurysmrupture. The performance of a prophylacticoperation to remove the threat of an aneurysmrupture, whether by conventional open repairor ER, cannot remove the associated risk of car-diovascular death that is the constant compan-ion of every atheromatous aneurysm.

COSTS OF ERAortic stent-graft devices are extremely expen-sive, an average of €7,400, and account for themajor part of the Interventional Radiologybudget in most major vascular units. The indi-vidual sections of stent-graft that may berequired to repair such devices during follow-

up are also proportionately expensive. TheEVAR trial analysed the costs both of the pri-mary procedure and the follow up period andestimated a mean added cost of £3,300 for ERover 4 years. This additional cost per patientclearly has a direct relationship with the cost-effectiveness of ER and has been used as anargument against the widespread funding ofthe technique as a routine treatment. Sincedevices and introduction systems are still in aphase of continued development, the overallproduction costs have not diminished.However, this is clearly an aspect of ER that willhave to be resolved with the device industry ifthe technique is ever to be applied as a routinepart of clinical care in the future.

CURRENT TRENDSThe current status of ER is still that of an inves-tigational technique which is undergoing agradual evolution. Continuing technologicaldevelopment has produced fenestrated andbranched stent-grafts and there is no doubtthat the clinical applications of such deviceswill become better defined over the next year.The use of ER for ruptured aneurysms is alsoattracting increasing levels of interest, the pro-vision of adequate levels of trained staff (out ofhours) being the limiting factor in most units.Hybrid procedures combining open andendovascular repair for thoraco-abdominalaneurysms are also on the increase. The currentfashion for monitoring endovascular deviceswith CT seems unlikely to be tenable in thelong-term because of the radiation penalties.MRI is not suitable for monitoring purposes inat least half of the devices presently beingdeployed. It should soon become possible to

Figure 1: Surveillance CT at 6 years after successful ER showingnearly complete resolution of the aneurysm sac

significantly reduce the frequency of detaileddevice scrutiny, if anticipated performanceimprovements are demonstrated within theregistries and trials. In the meantime, evermoreingenious methods of non-invasive monitoringare under investigation (Ellozy, J Vasc Surg,2004).

The continuing analysis of data in the publicdomain, from the international registries andthe trials mentioned above, has provided greatpublicity for the use of ER and this has reachedthe attention of the general public, certainlythose millions with access to the internet. Therehas been a noticeable increase in the numberof aneurysm patients who already have knowl-edge of stents and are anxious to avoid opensurgery. These patients cannot be told that ERis better than OR on the basis of the currentlyavailable evidence. However, the trial results dogive further credence to ER while discussing allthe treatment options as part of the consent-ing process.

The UK EVAR trial has been additionally fundedto provide longer term follow-up data and thisshould further inform the debate over the next4 - 5 years. By this time, medium term resultsfrom the current French and American RCTsshould also be available. Despite the lack oflong-term data, it seems that the numbers ofERs are increasing and it is very important thateach such procedure is registered and followedup. There is still a need for additional evidenceand thus each ER case, if not within an RCT,should at least be entered into a national reg-istry and undergo regular imaging surveillance.

M. SapovalT.J. Kröncke P. N. Lohle J.P. Pelage

CIRSE Foundation UFE Registry Registry inclusion is running high. As of begin-ning of August 2006, participation acrossEurope has already resulted in 488 patiententries.The mean age of patients entered currentlystands at 42.52 (SD 15.55). Prior to embolisa-tion patients complained of heavy menstrualbleeding (68.19%), bulk related symptoms(19.17%), and intermenstrual or menstrual pain(9.80%). 12.3 % of patients had undergone pre-vious myomectomy. The mean pre-embolisa-tion uterus volume was 572.65 cm³. A micro-catheter was used in 77.75 % of cases.

Recruitment of patients for the CIRSEFoundation UFE registry is continuing. The reg-istry is designed to allow for carefree and time-efficient inclusion of all consecutive patients

"ER for AAA: an overview of the current status"

John RoseConsultant Interventional Radiologist Freeman Hospital Newcastle upon Tyne Hospitals NHS Trust

undergoing UFE performed by CIRSE members.A short electronic questionnaire can be filled inwithin a few minutes and follow-up is limitedto key issues. Entry of more extensive data cap-ture is also possible including a quality of lifeand a pregnancy questionnaire. All dataentered by an individual site can be down-loaded for statistical analysis and research pur-poses in excel format.

With follow-up still pending and enrolment stillopen CIRSE Foundation invites all CIRSE mem-bers to participate and enter their patients. Fornewcomers go to www.cirse.org and click onFoundation, then Registry, or simply go towww.uferegistry.com

The Principal Investigators

This registry was made possible through the generous support of Terumo, Biosphere Medical, and Boston Scientific.Medical.

Special Edition / CIRSE 2006 - Rome

4 Advertorial Monday, September 11, 2006

In February 2006, the TARL (Talent AAARetrospective Long term) study was publishedin the Journal of Vascular Surgery . The analysiswas performed on 165 patients treated withthe first generation TALENT AAA stent graft in 9centres in Germany from 1996 to 1999. Themean follow up period was 53 months, with amaximum follow up period of up to 7 years.The study showed similar or superior outcomesachieved with the TALENT AAA stent graft com-pared with first generation stent grafts. Theresults also correlated well with those previous-ly published in single centre studies .

Although the first generation of TALENT AAAdid perform very well over time, a series oftechnological enhancements have been imple-mented over the last 10 years, which haveimproved the conformability and durability ofthe stent graft, as well as the accuracy and easeof use of the delivery system.

The first human implant with TALENT AAA inEurope was performed in 1996. Then, The LPSmaterial was introduced in 1999 and provideda lower profile. In 2000, the CoilTrac deliverysystem was launched with an improved flexibil-ity. In 2002 Medtronic began to apply a chemi-cal surface treatment of the Nitinol springs toincrease durability and changed the connect-ing bar in order to improve conformability. TheUniDOC system was also introduced makingTALENT more versatile. In 2004, Medtronic

introduced TALENT AAA with the XCELERANTdelivery system, which improved trackability,accuracy of delivery and ease of use. Recently,new standard sizes have become available totreat larger anatomies with proximal diameterup to 36mm.

Thanks to Medtronic's experience of workingwith physicians on more than 100,000 implantsworldwide, and to this continuous innovationprogramme, TALENT AAA has become the mostimplanted stent graft in Europe. It has provento be a reliable technological platform for stentgrafting of abdominal aortic aneurysms, asresults from the TARL study have shown.

Medtronic is committed to investing inendovascular therapy to help physicians treatmore patients with easy to use and reliabletechnologies.

Please come to the Medtronic booth at CIRSEto learn more about long term outcomes withthe TALENT AAA stent graft.

1Torsello G et al, Long-term outcome after Talent endograft implan-tation for aneurysms of the abdominal aorta: a multicenter retro-spective study. J Vasc Surg. 2006 Feb;43(2):277-84.

2Espinosa G et al, Six-year experience with Talent stent-graft repairof abdominal aortic aneurysms, J Endovasc Ther. 2005Feb;12(1):35-45.

TALENT™ AAA Stent Graft - A leading stent graft technology that has improved over time.

Advertorial

C RSECardiovascular and Interventional Radiological Society of Europe

5ProceduresIRnewscongress

Roberto GandiniDept. of Diagnostic Imaging, Molecular ImagingInterventional Radiology and Radiation TherapyUniversity of Rome Tor Vergata

The incidence of critical limb ischemia is esti-mated to be 50-100 per 100,000 every year andhas always been considered a primary indica-tion for bypass surgery2,3,4. Limb salvage rates >90% at one year are reported in contemporaryseries using bypass surgery. Unfortunately ade-quate vein is often unavailable and long-termresults of bypasses constructed with prostheticmaterials are much less satisfactory5,6. In recentyears the use of PTA as a primary treatment forCLI has been increasing due to the continuingadvances in imaging techniques, angioplastyequipment (such as low profile balloons andnew guidewires) and endovascular expertise7.

The clinical advantages of PTA are well estab-lished, especially for high-risk, elderly and vas-cularly compromised patients: there is no needfor general or spinal anaesthesia, there are noor fewer surgical wounds especially dangerousin diabetic patients, the hospital stay is shorter,complication and mortality rates are low8,9 anda failed PTA attempt does not preclude a sub-sequent by-pass graft10. In patients treated toavoid a major amputation due to CLI the firstand most important aim is limb salvage. Thiscan only be achieved by obtaining a direct flowto the foot.

Despite the existence of several studies thatshow the predominant role of PTA as primarychoice for CLI treatment, the same also reporthigh rates of technical unfeasibility in thesepatients. For example; in a study including over219 selected patients submitted to endovascu-lar treatment, the feasibility rate was 87.2%while in the remaining 12.8% the procedurewas unfeasible9. In the audit of the Basil study,out of the 456 patients with infra-inguinal CLIpresenting to the top six UK recruiting centres,only 70 (29%) were suitable for randomisationinto the study. The remaining 386 patients didnot qualify for randomisation and 75 (16%) ofthese were considered technically unsuitablefor angioplasty10. In a recent study in 1188 dia-betic patients undergoing revascularisation,PTA was performed in 83,6% while in theremaining 16.4% the procedure was unfeasibledue to complete calcific vessel occlusion notallowing the passage of the balloon catheter11.

In our experience, the use of different endovas-cular techniques including peripheralapproaches (such as trans-popliteal and/ortrans-pedal), adequately selected for eachpatient, allows to increase the indication forPTA to approximately 97% of the patients.Between June 2001 and June 2005 we treated469 (305 males, 164 females; mean age: 69.5years, range: 34-82 years) consecutive diabeticpatients with deep chronic foot ulcers compli-cated by ischemia and infection by endovascu-lar revascularisation. The patients were classi-fied according to the University of TexasDiabetic Wound Classification System (16) as:stage II B in 48 (10.23%), stage II C in 59(12.57%), stage II D in 81 (17.27%), stage III A in12 (2.56%), stage III B in 85 (18.12%), stage III Cin 95 (20.25%) and stage III D in 89 (19%)patients. Most of the patients were candidatesfor major amputation. Our treatment protocol,regardless of the length, number and localisa-tion of the obstructions, involves an attempt ofPTA revascularisation in all diabetic patientswith stenotic and obstructive vascular lesionsof the lower limb (iliac, superficial femoral andinfrapopliteal artery obstructions). The lack of

visualization of the vessel at the plantar archand/or of the pedal artery was the only real cri-terion of exclusion. The 469 patients were allinsulin-dependent dibetics. The risk factors forcardiovascular disease, besides diabetes, weresmoke in 335 (71.43%) patients (225 ex smok-ers), hypertension in 426 (91%), dislypidemia in89 (18.9%), chronic renal failure with hemodial-ysis in 58 (12.5%), coronary artery disease in164 (35%), of whom 35 had already undergoneaorto-coronary by-pass.

An angio-MRI examination indicated 12patients had an IA obstruction, 41 patients hada segmentary obstruction of SFA and of the PA,299 patients had an obstruction of the AT, PTand the IA; 102 patients had an obstructionboth of the SFA and the PA and of limb vessels(AT, PT and IA); and 15 patients had an obstruc-tion of PT at the plantar arch or pedal artery. In36 patients with infra-popliteal artery obstruc-tion, antegrade recanalisation through thetransfemoral access was impossible. In thesepatients revascularisation of the obstructedvessels was performed using a "doubleapproach", with a proximal access at the com-mon femoral artery and a distal access at thefoot. The distal access was the pedal artery incase of the revascularisation of the anterior tib-ial artery and the distal segment of the posteri-or tibial artery in case of the revascularisationof the posterior tibial artery itself. The casesrequiring this type of "double approach" had atleast one of the following conditions: 1) occlu-sion of the three leg vessels from their origin; 2)popliteal artery obstruction the lesion couldnot be passed or the vessel's origin could notbe reached by an antegrade approach; 3) alarge collateral vessel which could be confusedwith the proximal segment of one of the mainleg vessels; 4) impossibility to re-enter into thetrue lumen of the vessel once the lesion waspassed using subintimal angioplasty technique.

When there is an obstruction of the SFA orpopliteal artery with just a single patent vesselin the leg, the "double approach" is the besttechnique to be used in order to optimize theresults when we have a good inflow with only asingle good outflow. Distal puncture has to beperformed in a patent arterial segment with anadequate calibre and a slow blood flow usingUS guidance only for non-calcified arteries. Incases with heavily calcific arteries, US guidanceis useful to detect the vein and therefore facili-tate the orientation of the needle during punc-ture under fluoroscopic guidance. The rest ofthe procedure is carried out under fluoroscopicguide. In 22 out of 36 cases, the distal puncturewas made using a 20-gauge micropunctureneedle kit followed by the introduction of thePT Graphix Super Support guide wire; in 11cases the puncture was made with an 18-gauge needle followed by the insertion of ahydrophilic 0.035 in. guide wire; only in 3 casesa short 4F introducer sheath (Terumo) had tobe used to give additional support to the guidewire. After the introduction of the guide, thishas to be advanced until the occlusion ispassed. Subsequently, using the "rendez-voustechnique" the tip of the guide has to beinserted into the catheter placed through thefemoral access.

In 2 particular cases with sever alterations oflower limb vessels, a double distal puncturewas performed: in one case of the anterior tib-ial and posterior tibial artery and in the otherof the posterior tibial and peroneal artery. Inboth cases we obtained a direct flow to thefoot. No complications related to distal punc-ture occurred. In 4 cases, despite of the pas-sage of the guide wire from the distal patentvessel to the proximal patent vessel and theexecution of a prolonged PTA, a direct flowcould not be established, probably due to adissection or another obstacle that could notbe detected. Maybe this problem could besolved in the near future by using dedicated

long stents. In these 36 cases, 80% of whichwere IIID/IIIC stage, we obtained a 100% tech-nical success for recanalisation, an 89% techni-cal success for PTA (due to the 4 cases of proba-ble dissection and the 2 major amputationsdue to osteomyelitis despite of a successfulPTA). Limb salvage rate in these patients wasthereby 83%. This technique was associated toa higher technical success rate (96.8%) andallowed to increase the rate of limb salvage.The feasibility of this procedure is very highconsidering that it was performed consecutive-ly in our entire patient population with theonly contraindication being the absence offlow in the pedal artery and the plantar arch.Furthermore our technique is associated tolower costs when compared to vascular sur-gery, as demonstrated by the BASIL trial1.

References:1 Adam DJ, Beard JD, Cleveland T, Bell J, Bradbury AW, Forbes JF,

Fowkes FG, Gillepsie I, Ruckley CV, Raab G, Storkey H; BASIL trialparticipants. Bypass versus angioplasty in severe ischaemia of theleg (BASIL): multicentre, randomised controlled trial. Lancet. 2005Dec 3;366(9501):1925-34.

2 Blair JM, Gewertz BL, Moosa H, Lu CT, Zarins CK. Percutaneoustransluminal angioplasty versus surgery for limb-threateningischemia. J Vasc Surg 1989;9:698-703.

3 Treiman GS, Treiman RL, Ichikawa L, Van Allan R. Should percuta-neous transluminal angioplasty be recommended for treatmentof infrageniculate popliteal artery or tibioperoneal trunk stenosis?J Vasc Surg 1995;22:457-65.

4 Parsons RE, Suggs WD, Lee JJ, Sanchez LA, Lyon RT, Vrith FJ.Percutaneous transluminal angioplasty for the treatment of limbthreatening ischemia: do the results justify an attempt beforebypass grafting? J Vasc Surg 1998;28:1066-71.

5 Alber M, Romiti M, Brochado-Neto FC, Pereira CAB. Meta-analysisof alternate autogenous vein bypass grafts to infrapopliteal arter-ies.Eur J Endovasc Surg. 2003 Mar;25:229-34.

6 Ishii Y, Gossage JA, Dourado R, Sabharwal T, Burnand KG.Minimum internal diameter of the greater saphenous vein is animportant determinant of successful femorodistal bypass graftingthat is indipendent of the quality of the runoff. Vaqscular2004;12:225-32.

7 Molloy KJ, Nasim A, London NJ, Naylor AR, Bell PR, Fishwick G, etal. Percutaneous tranluminal angioplasty in the treatment of criti-cal limb ischemia. J Endovascular Ther 2003;10:298-303.

8 Salas CA, Adam DJ, Papavassiliou VG, London NJ. Percutaneoustransluminal angioplasty for critical limb ischaemia in octogenari-ans and nonagenarians. Eur J Vasc Endovasc Surg 2004;28:142-5.

9 Faglia E, Dalla Paola L, Clerici G, Clerissi J, Graziani L, Fusaro M,Gabrielli L, Losa S, Stella A, Gargiulo M, Mantero M, Caminiti M,Ninkovic S, Curci V, Morabito A. Extensive use of peripheral angio-plasty, particularly infrapopliteal, in the treatment of ischaemicdiabetic foot ulcers: clinical results of a multicentric study of 221consecutive diabetic subjects. J Intern Med. 2002 Sep;252(3):225-32.

10 Faglia E, Favales F, Quarantiello A, Calia P, Brambilla G, RampoldiA et al. Feasibility and effectiveness of peripheral percutaneoustransluminal angioplasty in diabetic subjects with foot ulcers.Diabetes Care 1996;19:1261-1264.

11 Faglia E, Dalla Paola L, Clerici G, Clerissi J, Graziani L, Fusaro M,Gabrielli L, Losa S, Stella A, Gargiulo M, Mantero M, Caminiti M,Ninkovic S, Curci V, Morabito A. Peripheral angioplasty as the first-choice revascularization procedure in diabetic patients withCLI:prospective study of 993 consecutive patients hospitalizedand followed between 1999 and 2003. Eur J Vasc Endovasc Surg2005;29,620-627

How I do it: Proximal and Distal Approach

Figures 1a,1b: Preliminar angiography shows apatent peroneal artery with occlusion of anteriortibial artery at the origin and proximal occlusionof the posterior tibial artery with patent pedalartery and plantar arch

Figure 2: Recanalization of posterior tibial arterywas not possible with either endoluminal orsubintimal antegrade approach

Figures 3a,b: Puncture of the distal segment of theposterior tibial artery using a 20 Gauge needle

Figure 4: Advancement of the guide wire inthe true lumen delimited by the calcific ves-sel walls

Figure 5: Rendez-vous

Figures 6-8: PTA of the posterior tibial artery form itsorigin to the plantar arch using a 2-mm-diameterand 12-cm-long balloon catheter

Figures 9-10: Post-procedural angiography show-ing the normal patency of the posterior tibial andperoneal artery

Special Edition / CIRSE 2006 - Rome

6 Protection in IR Monday, September 11, 2006

Carotid artery stenting (CAS) can nowadays beconsidered a valid therapeutic option for thetreatment of stenoses of the extracranialcarotid artery. However, this procedure has anincidence of neurological complications due todistal embolization ranging from 3,2 % to 10 %12.In order to reduce the rate of periproceduralneurological complications, various cerebralprotection systems have been proposed, thepurpose of these system being to capture theemboli before they can reach the brain.

The first system was described by Théron3 in1990. He introduced the concept of preventionof cerebral embolization and employed tempo-rary balloon occlusion of the distal internalcarotid artery (ICA) during percutaneous trans-luminal angioplasty. Since this initial experi-ence, several studies have been carried outusing different protection devices, which haveshowed a reduction of the neurologicalperiprocedural complication rate. The globalcarotid artery stent registry described a periop-erative stroke and death rate of 5.9% in proce-dures performed without protection devicescompared to a rate of 2.23 % in those carriedout with the devices4. Boltuch et al.5 evaluated651 patients treated both with (N=180) andwithout (N=471) cerebral protection and foundbetter results for the protected population;technical success: 99% vs 95%; complicationsrate: 10% vs 18.3%; TIA: 2.8% vs 3.2%; MAE:0.6% vs 2.1%.

Cerebral protection devices (CPD) can be divi-dend into three different types: filters, distalocclusion balloons and proximal protectionsystems. In filter systems, flow is maintainedand emboli are captured and removed togeth-er with the device by retraction of the system.Balloon occlusion devices and proximal protec-tion systems block the flow into the ICA andemboli are aspirated before balloon deflationand catheter removal.

Distal Occlusion BalloonsDistal Occlusion Balloons consist in a 0.014"guide-wire equipped with a distal balloon thatis inflated through a small channel presentwithin the wire. Once the lesion is crossed withthe guide-wire, the balloon is positioned abovethe lesion and inflated in order to completelyocclude the ICA, thus avoiding the passage ofmicroemboli. After treatment of the lesion, acatheter is advanced up to the balloon and theblood proximal to the balloon, possibly con-taining the debris dislodged from the athero-ma, is aspirated and removed. The advantagesof this type of CPD are the very low profile (2.2FR), the good flexibility and torquability of thesystem. On the other hand, as this system pro-duces a complete occlusion of the ICA, thatcannot be tolerated in 6-10% of the patients7.

FiltersFilters consist of a metallic structure coated bya membrane of polyethylene which can havedifferent shapes. The membrane presents sev-eral holes with a diameter ranging from 80 to220 µm (Fig.1). Once the lesion is crossed, thefilter is opened in the ICA lumen and thenretrieved at the end of the procedure. As filtersproduce a marked reduction of the flow withinthe ICA, they should not be left in place formore than 15 minutes. Different types of distalfilters are now commercially available:Angioguard XP (Cordis-Johnson & Johnson),FilterWire EZ/EX Embolic Protection System -EPI (Boston Scientific), Spider TM (EV3),AccuNet Rx Embolic protection Device(Guidant), Rubicon Filter (Rubicon), MedNovaEmboShield Cerebral Protection System(Abbott), Interceptor (Medtronic), Trap filter(Microvena). Others are currently being devel-oped.

Proximal protection systemsProximal protection systems provide completeprotection avoiding any passage of the devicesthrough the lesion. These systems are based onthe inflation of an occlusion balloon at the levelof the common carotid artery (CCA) and at theorigin of the external carotid artery (ECA), caus-ing inversion (Parodi system) or the completestop of the flow (MOMA) within the ICA. Afterocclusion of the common and external carotidartery, the collateral flow through the circle ofWillis creates the so-called "back pressure"which prevents antegrade flow into the ICA.After the lesion has been stented, the stagnantblood present within the ICA, possibly contain-ing embolic material, is aspirated and removed

or filtrated. Proximal protection systems cannotbe used in all cases, since 6-10% of the patientsdo not tolerate complete flow occlusion6.

CPD may also be considered the cause of someprocedural complications; the most frequent ofwhich are: a) inability to cross a lesion, b) failureto capture the emboli and c) vasospasm orinjury of the arterial wall.Inability to cross the lesion: The deployment ofa CPD should generally not be a problem instraight anatomy, while in patients with verytortuous vessels and tight stenoses it is often atechnical challenge to cross the lesion withoutcomplications.

Failure to capture the emboli: Capture efficien-cy, obviously, is the most important aspect ofCPD. It can be hindered by a number of differ-ent mechanisms and is dependent on whichtype of device is used. Using the distal balloonsystems a rare but possible complication is thegradual deflation of the balloon resulting ininadvertent reestablishment of blood flowtoward the brain. This phenomenon can beprevented by constantly monitoring the size ofthe balloon under fluoroscopy or by injectingcontrast medium during the procedure.However an excessive inflation of the balloonwill increase the risk of vessel spasm or dissec-tion.

Another potential source of neurologicaleffects is the embolization of the ECA territory.Since balloon occlusion causes turbulencewithin the occluded ICA segment, some embolimay pass in the ECA before post-procedureaspiration, thus determining ECA territoryembolization. This event determines a greaterrisk of embolization via ECA-to-ICA collateralswhich open up during ICA occlusion. Severalauthors have evaluated the efficacy of filtersusing different models. All the filters were ableto capture the vast majority of particles, espe-cially the large ones.

However, it is known that 50% of the embolireleased during CAS are smaller than 100 µm7.Smaller pore size may decrease the chances ofmicroembolization. However, it also resulted ina higher incidence of filter thrombosis. Filterthrombosis is related to filter plugging as aresult of capturing too many particles and/orfibrin deposition. Therefore the selection of thepore size is a compromise between the risk offilter thrombosis and the risk of microemboliza-tion. Another cause for embolization despite

Figure 1a: The patient was a 59 year old malepatient with multiple risk factors (hypertension,heavy smoker, diabetic) symptomatic for a severestenosis of the left ICA with ulcerated plaque

Figure 2b: In September 2005 the patient under-went a protected CAS with an Angioguard filterdevice (Ø 6 mm) and a Precise Nitinol stent (8x30mm)

Figure 2c: At the end of the procedure a severespasm of the ICA, at the level of the filter, wasclearly evident and…

Figure 2d: …completely solved after injecting 0.2ml of Nitro-glycerine. No symptoms occurred dur-ing the procedure and after filter removal

Figure 1: After removal of a filter protection sys-tem (Angioguard Cerebral Protection Device,Cordis-Johnson & Johnson), a large amount ofdebris were captured during the procedure, whichis clearly visible inside the filter

adequate filtering capability is an incompleteadherence of the filter to the vessel wall. Thiscondition mainly occurs in tortuous vesselswhere the filter is not aligned with the longaxis of the ICA and particles may flow aroundthe device. For this reason it is mandatory toplace the filter in a straight portion of the ves-sel, whenever this is possible. A similar condi-tion occurs when an incorrect filter size, smallerthan the arterial diameter, is selected.

Injury of the arterial wall: As we all know, theICA is a relatively delicate vessel. Since any dis-tal protection device exerts some forces on thevessel to achieve complete apposition, irrita-tion of the arterial wall may occur. The degreeof irritation increases with the movement ofthe protection device, which is inevitable evenin experienced hands. Although most episodesof spasm are self-limiting and do not result inclinical sequelae, the long-term effect of suchspasm in the development of intimal hyperpla-sia is unknown8. In the majority of cases spasmcan be easily solved by intrarterial injection ofvasodilators (Fig.2). Damage to the intimal layermay occur due to unexpected movement ofthe inflated balloon or deployed filter basketby the operator or neck movement by thepatient. This may result in dissection of the ICA,which has been described by Muller-Hulsbeck9.

ConclusionsCarotid artery angioplasty and stenting proce-dures should always correlate with distalembolization, although most embolizationdoes not produce clinical manifestations.Several studies have proved that the use ofcerebral protection devices drastically reducesthe incidence of distal microembolization. Forthis reason a routinely use of CPDs should beconsidered mandatory.

Cerebral Protection Devices in CAS

Fabrizio FanelliDepartment of Radiological Sciences -Interventional Radiology UnitUniversity of Rome La Sapienza

References:1) R. Zahn, E. Roth, T. Ischinger et al. Carotid artery stenting in clini-

cal practice Results from the Carotid Artery Stenting (CAS) - reg-istry of the Arbeitsgemeinschaft Leitende KardiologischeKrankenhausärzte (ALKK). Z Kardiol. 2005 Mar;94(3):163-72.

2) Dominick J.H. McCabe, Anthony C. Pereira, Andrew Clifton et al.Restenosis after carotid angioplasty, stenting or endarterectomyin the carotid and vertebral artery transluminal angioplasty study(CAVATAS). Stroke. 2005;36:281-286

3) Theron JP, Payelle GG, Coskun O, et al. Carotid artery stenosis:treatment with protected balloon angioplasty and stent place-ment. Radiology 1996; 201.627-636.

4) Wholey MH, Al-Mubarak N, Wholey MH. Updated review of theglobal carotid artery stent registry. Cath Cardiovasc Interv 2003;60:259-266.

5) Boltuch J, Sabeti S, Amighi J, et al. Procedure-related complica-tions and early neurological adverse events of unprotected andprotected carotid stenting: temporal trends in a consecutivepatient series. J Endovasc Ther 2005; 12:538-547

6) Al-Mubarak N, Roubin GS, Vitek JJ; et al. Effect of distal-balloonprotection system on microembolization during carotid stenting.Circulation 2001; 104:1999-2002

7)Whitlow PL, Lylyk P, Londero H, et al. Carotid artery stenting pro-tected with an emboli containment system. Stroke. 2002;33:1308-1314

8) Reimers B, Corvaja N, Moshiri S, et al. Cerebral protection with fil-ter devices during carotid artery stenting. Circulation 2001;104:12-15

Figure 2: Vessel spasm occurred during protected CAS using distal filter protection device

9) Muller-Hulsbeck S, Stolzmann P, Liess C, et al. Vessel wall damagecaused by cerebral protection devices: ex vivo evaluation inporcine carotid arteries. Radiology 2005; 235(2):454-460.

C RSECardiovascular and Interventional Radiological Society of Europe

7Vena Cava FiltersIRnewscongress

Optional vena cava filters, also called retriev-able filters, are to this day the most interestingand intelligent improvement in vena cava filtra-tion devices. Indeed for almost a century, par-tial interruption of the vena cava has proven tobe the least damaging solution for preventingpulmonary embolisms (PE) in patients who arenot eligible for conventional anticoagulation,and a lot of permanent vena cava filters havebeen proposed.

Unfortunately there have been many severecomplications mainly due to the permanentcharacter of the filters. Today we have at ourdisposal devices that can be easily withdrawnwhen the patient does not need them anylonger or when the patient can receive regularanticoagulant therapy again. In addition, thesefilters can be left in place like the conventional,permanent filters, if the clinical status of thepatient has changed or if the risk of pulmonaryembolism remains at a high level.

At the moment five optional filters are available(see chart). Others are expected to be market-ed soon (G2 from Bard, Celect Filter from Cook).In our practice we have chosen the French filter(ALN), because of its easiness of insertion andretrieval and more particularly because of itsunlimited retrieval delay. With this device wehave been able to perform retrieval 25 monthsafter its insertion without experiencing any dif-ficulties.

Our indications for an optional vena cava fil-ter are essentially the same as for perma-nent filters: � permanent or temporary contraindication to

anticoagulant therapy� recurrent PE despite adequate anticoagula-

tion� documented extension of venous clots

despite a well adapted therapy� PE in high risk patients for which anticoagu-

lant may not be sufficient to prevent a fataloutcome

The possibility to retrieve the filter allows usto be more confident for previously dis-cussed and questionable prophylactic indi-cations:� A floating very proximal thrombus (iliac or

caval) in patient with PE� Primary prevention in the situations with

high risk such as :- cancer at a final stage- orthopaedic surgery- multi injury in fragile patie nts- pregnancy

� Preventive and exclusive treatment beforesurgery

� Exclusive preventive treatment for elderlypatients

Beside these optional filters we limit the useof the truly temporary filters (which are veryuncomfortable for the patients and theirclinical monitoring, leading to thromboticand infectious complications) to a very limit-ed number of situations, such as the follow-ing:� During thrombotic therapies� As a protective device while we have decided

to perform a thromboaspiration of a partiallythrombosed filter

� When the filtration delay should be very short(a few days perioperative period) in order toavoid a potential second, aggressive proce-dure

� In the last days of a pregnancy, in which casethe filter should be positioned above therenal veins

We also limit the placement of truly perma-nent filters to a very small number of indica-tions:� For patients with infrequent mega vena cava

(Bird's Nest Filter)� Due to their lateral legs, which allow better

caval centering, we prefer using devices withindisputable stability (like the LGM) for veryold patients in whom the retrieval is notquestionable or in whom the vena cava is tor-tuous

For the near future, we need more evaluationsof the benefit/risk ratio of these devices andabove all a better analysis of the feasibility ofthe retrieval.

Although in our personal series we did not faceany complication due to the anchoring of thestruts, it is vital to organize longer studies inorder to quantify the potential gross andmicroscopic lesions that might occur in thevena cava wall.

References :1. Kearon C. Natural history of venous thromboembolism.

Circulation 2003; 107(23 Suppl 1): I22-302. Buller HR, Agnelli G, Hull RD, et al. Antithrombotic therapy for

venous thromboembolic disease : the Seventh ACCP Conferenceon Antithrombotic and Thrombolytic Therapy. Chest 2004; 126(3Suppl):401S-428S.Erratum in:Chest 2005;127 (1):416

3. Streiff MB. Vena cava filters: a comprehensive review.Blood 2000;95:3669-3677

4. Decousus H, Leizorovicz A, Parent F, et al. A clinical trial of venacaval filters in the prevention of pulmonary embolism in patientswith proximal deep-vein thrombosis. Prevention du Risqued'Embolie Pulmonaire par Interruption Cave Study Group. N EnglJ Med 1998 ; 338 :409-415

Figure 1 : ALN

Figure 2 : Recovery

Figure 3 : Gunther Tulip

Figure 4 : Optease

Figure 5 : Safeflo

Optional vena cava filter: The way I see it

F.G. BarralService de Radiologie,CHU Bellevue, Saint-Etienne, France

5. The PREPIC Study Group. Eight-year follow-up of patients withpermanent vena cava filters in the prevention of pulmonaryembolism : The PREPIC (Prevention du Risque d'EmboliePulmonaire par Interruption Cave) randomized study. Circulation2005; 112:416-422

6. Kinney TB. Update on inferior vena cava filters. J Vasc Interv Radiol2003; 14:425-440

7. Millward SF, Grassi CJ, Kinney TB, et al. Reporting standards forinferior vena cava filter placement and patient follow-up: supple-ment for temporary and retrievable/optional filters. J Vasc IntervRadiol 2005; 16:441-443

8. Hull RD. Changes in the technology of inferior vena cava filterspromise improved benefits to the patient with less harm, but apaucity of evidence exists. J Thromb Haemost. 2005; 3:1368-1369

9. Millward SF, Oliva VL, Bell SD, et al. Gunther Tulip Retrievable VenaCava Filter: results from the Registry of the CanadianInterventional Radiology Association. J Vasc Interv Radiol 2001;12:1053-1058

10. Pieri S, Agresti P, Morucci M, et al. Optional vena cava filters : pre-liminary experience with a new vena cava filter. Radiol Med(Torino). 2003; 105:56-62

11. Stein PD, Alnas M, Skaf E, et al. Outcome and complications ofretrievable inferior vena cava filters. Am J Cardiol 2004; 94:1090-1093 16

12. Pancione L, Mecozzi B. Permanent/removable vena cava filterALN (France): our experience with 96 patients

13. Morris CS, Rogers FB, Najarian KE, et al.Current trends in venacava filtration with the introduction of a retrievable filter at a levelI trauma center. J Trauma 2004; 57:32-36

14. Cheung MC, Ash MR, Ghandi S, et al. Temporary inferior venacava filter use in pregnancy. J Throm Haemost 2005; 3:1096-1097

15. Imberti D, Bianchi M, Farina A, et al. Clinical experience withretrievable vena cava filters :results of a prospective observationalmulticenter study. J. Thromb Haemost 2005; 3:1370-1375

16. Asch MR, Initial experience in humans with a new retrievableinferior vena cava filter Radiology 2002; 225:835-844

17. Offner PJ, Hawkes A, Madayag R, et al. The role of temporaryinferior vena cava filters in critically ill surgical patients. Arch Surg2003; 138:591-594; discussion 594-595

18. Bangalore C Anil Kumar, Chakraverty S, Zealley I Failed retrievalof potentially retrievable IVC filters: a report of two cases.Cardiovasc. Intervent. Radiol 2006, 29:126-127

19. Rosenthal D, Wellons E.D., Lai K.M., Bikk A, Retrievable inferiorvena cava filters: early clinical experience. J Cardiovasc Surg2005;46:163-9

Special Edition / CIRSE 2006 - Rome

8 Lung Tumour Ablation Monday, September 11, 2006

Today image-guided percutaneous ablation isconsidered a valuable treatment option forpatients with primary hepatocellular cancer orlimited liver metastases. As the technologyevolves, percutaneous ablation is now being eval-uated for other types of tumours.

The lung is the most common site for primarycancer worldwide and a common site formetastatic disease. Many of the patients are notsuitable for surgical treatment, often due to theirage, poor cardiovascular or respiratory functionor other serious coexisting health conditions.Hence, it is logical to extend the use of percuta-neous ablation to patients with limited lungtumours not eligible for surgical resection.

A careful pre-treatment assessment is essential,including chest CT to determine the exact sizeand position of the target tumours. During theprocedure, a radiofrequency (RF) needle elec-trode is positioned in the tumour, using the sameguidelines as for CT-guided lung biopsy. The skinentry site is selected so as to allow the shortestand most vertical path for the needle, avoidingblood vessels, interlobar fissures and bullae. It isparticularly important to ensure the correct

Figures 1a,b: Three-dimensional reconstructions of multidetector spiral CT data sets show correct placement ofthe RF needle into the tumour

placement of the electrode needle within thetumour, using image reconstructions in multipleplanes.

Initial studies have indicated that RF ablation iswell tolerated by most patients and that it canachieve complete necrosis of the targeted lesion.We recently completed a large prospective, multi-centre trial in patients with primary lung canceror lung metastases 3.5 cm or less in diameter whowere not candidates for surgery. One hundredand six patients (36 women and 70 men) with186 malignant tumours were enrolled in this trial.Thirty-three patients suffered from non-small celllung cancer, 53 had colorectal cancer metastasesand 20 had metastases from other primary malig-

nancies; none were suitable for surgery. Patientsunderwent RF ablation treatment with CT guid-ance and under conscious sedation. No proce-dure-related deaths occurred. There were 27cases of pneumothorax requiring treatment, 4pleural effusions, 2 cases of pneumonia and onecase of atelectasis.

At a CT evaluation 3 months after the procedure,complete ablation of the tumour was observed in173 of 186 tumours, resulting in a primary effec-tiveness rate of 93%. Overall survival of the pri-mary lung cancer patients was 69% at one yearand 49% at two years. However, many of thedeaths were not cancer related and when thesewere excluded, the cancer-specific survival rates

Radiofrequency (RF) tumor ablation is nowwidely used for the treatment of primary andmetastatic tumors in various organs. The ther-mal lesions created are caused by the applica-tion of alternating current and are influencedby the heat transfer within the tissues.Numerous publications demonstrate the safetyand efficacy of radiofrequency ablation andindicate few complications in the treatment oflung tumors. However assessment of the tech-nical success of RF ablation is difficult becausethe treated tumor remains in place. Due to thenecessity of ablating margins to ensure a com-plete treatment of the tumor, normal tissuesurrounding the tumor undergoes coagulationnecrosis which may lead to size increase of theimaged abnormality. After having grown thelesion progressively shrinks. In some cases nosignificant shrinkage is observed, and thetumor remains larger post treatment than priorto treatment, even in the case of completetreatment without any residual viable tissue.For these reasons on CT follow up, lesion meas-urement based on RECIST (ResponseEvaluation Criteria In Solid Tumors) is notalways a reliable measure of ablation success. To perform an early assessment of the pres-ence and location of a residual viable tumor, inorder to retreat, a single CT based on tumorsize is insufficient and misleading. Contrast

material-enhanced CT imaging allows appreci-ation of the degree of tumor necrosis (Lee et alRadiology 2004; 230:125-34). Other publica-tions describe the utility of contrast-mediuminjection in the follow up. After treatment anincrease in contrast uptake might be due totumoral neo-vascularisation or to inflammatoryreaction. Comparing contrast uptake profilesobtained after treatment could allow depictionof a residual tumor. In this way MRI whichoffers high contrast and temporal resolution,could be useful. PET is now essential in the diagnosis and stag-ing of some cancers, and is used also for evalu-ation of the therapeutic response. After lung RFablation Akeboshi et al (JVIR 2004; 15 : 463-70)demonstrated PET to be more sensitive andspecific than contrast material-enhanced CT fordetection of residual tumor. A prospective study declared to the NCI(National Cancer Institute;(http://cancernet.nci.nih.gov/clinicaltrials) hasbeen designed. This study aims to evaluate theaccuracy of PET to measure the efficacy of RFablation of lung metastasis, and also to deter-mine the optimal delay of performing PET inthis particular indication.The ability to detect early residual tumor is anessential point in the follow up of the patientsafter radiofrequency ablation; assessment oflesion diameter by CT is often insufficient,other functional investigations are sometimesnecessary.

This article reflects the opinion of the authors.

Learn more about PET & Lung RadiofrequencyAblation with Dr. Jean Palussière at BostonScientific Meet with the Experts Session on Saturday 9thfrom 10:30 to 11:15.

Fig 1: Lung colo-rectal metastasis treated by RF ablation. 6 Months later the lesionremained nodular and larger than before the treatment, PET indicates that a com-plete ablation was achieved with no captation of 18 F-FDG inside the nodule

PET and Lung radiofrequency ablation

Advertorial

Dr. Jean PalussièreDr. F. Bonichon Institut BergoniéBordeaux (France)

Lung tumour ablation: Where are we going?

Riccardo LencioniDepartment of RadiologyUniversity of Pisa

were 91% at one and two years. In patients withlung metastases from colorectal cancer, the sur-vival rates were 88% at one year and 72% at twoyears, after exclusion of non-cancer-relateddeaths.

These results are encouraging and suggest thatRF ablation can improve survival, reduce pain andimprove quality of life in patients with unre-sectable lung tumours. However, additional clini-cal trials are required to further evaluate the placeof RF ablation in the management of primarytumours and metastases in the lung, either aloneor in conjunction with chemotherapy or radio-therapy.

C RSECardiovascular and Interventional Radiological Society of Europe

9AdvertorialIRnewscongress

Clinical benefits of flat panel 3D rotationalangiography for vascular interventions

Advertorial

Dr. V. Vidal, Prof. J.M. Bartoli, Centre HospitalierUniversitaire La Timone, Marseille, FranceC. Felix, P. Gobert, GE Healthcare, Buc, France

Case 1 : Pulmonary fistula embolizationCase HistoryA 67 year old female suffering from the RenduOsler disease, and who has been diagnosed onCT as having an arterio-venous fistula in theright pulmonary artery. This fistula has devel-oped between the middle lobe branch and thesuperior pulmonary vein in the right lung.Procedure detailsThe patient is programmed in the angio suiteto undergo embolization of the pulmonary fis-tula. The 2D angiography images show the fis-tula (fig. 1), but there is difficulty in clearlydelineating the feeding arteries with the pro-jection images. A pre-therapeutic Innova 3Dangiography is required in order to define pre-cisely the angio architecture of the fistula, iden-tifying if there are single or multiple feedingarteries. A selective catheterization is per-formed using a pig-tail catheter in the rightpulmonary artery. A 5-second 3D rotationalangiography is performed with the injection of42 ml of contrast media at 6 ml/s.

Fig.1 DSA

Fig. 2 3D VR showing fistula

Fig. 4 During embolization

Fig. 5 At the end of embolization

Fig. 6 Pulmonary fistula

Fig. 7 Post-embolization

Fig. 3 0.7 mm oblique slice showing re-stenosis

Fig. 4 0.7 mm slice orthogonal to stent axis

Fig. 5 Tight stenosis within stent

Fig. 6 Curved view of right carotid

Fig. 7 Calcified plaque at subclavian ostium

Fig. 8 Right subclavian artery

Fig. 9 Intra-stent angioplasty

Fig. 10 Post-procedure control

Fig. 1 2D DSA and Fig. 2 3D VR images of the archof the aorta and its branches

Fig. 3 Sagittal view

Discussion and conclusionThe morphology of the fistula is clearly visual-ized in 3D (figs. 2, 3) with the single feedingartery and a single draining vein. The fistula ismeasured to be around 15 mm in the 3Dimages. The pathway for micro-catheter posi-tioning and the appropriate coil sizes are also

At the end of the procedure, an Innova 3D rota-tional angiography acquisition is performed inorder to verify the complete filling of the fistula(figs. 6,7). The devascularization is completewith complete exclusion of the arterio-venousmalformation. The middle lobe branch and itscollateral arteries are patent.

Case historyA 50 year old male having undergone angio-plasty in the supra-aortic trunk for a brachio-cephalic artery stenosis in April 2005. Thepatient complains of a symptomatic pain in theright arm.Procedure details2D angiography exams (fig. 1) show an in-stentrestenosis of the brachiocephalic trunk, whoseeccentric and tight lesion is difficult to quantifyin the presence of the stent. A 5 second Innova3D rotational angiography exam is performed(60 ml of contrast media at 12 ml/s) to visualizethe stenosis morphology within the stent andquantify the stenosis using the multiplanar vol-ume reconstructions. Both 3D volume rendered(fig. 2) and cross-sectional images are automat-ically computed and simultaneously displayedon the workstation.

Discussion and conclusionsThe in-stent restenosis is clearly visualized inthe double oblique MPVR views (fig. 3, 4).The stent in the brachiocephalic trunk coversthe ostium in its proximal part, and distallyends 5-10 mm before the right commoncarotid and right subclavian bifurcation.

The in-stent re-stenosis due to myointimalthickening is evaluated at 85% in the recon-structed cross-sections, the most severe steno-sis being located at the middle part of the stent(fig. 5). The diameter of the normal part of thebrachiocephalic artery is measured to be 10mm and its length is measured to be 21 mm.

An atheromatic calcified plaque (fig. 6, 7)extends beyond the stent edge onto the lowerside of the right subclavian artery causing a50% ostial stenosis of the right subclavianartery. The other sections of the right subcla-vian artery are of normal morphology (fig. 8).

The right common carotid, the left subclavianand the left common carotid arteries are nor-mal. In conclusion, Innova 3D with multiplanar vol-ume reconstruction showing vessels, soft tis-sues, bone structures and devices allows acomprehensive and precise evaluation of com-plex pathologies such as this in-stent eccentrictight lesion in the supra-aortic trunk. For suchpathologies, there is a clear advantange inusing a single Innova 3D rotational angiogra-phy for pretherapeutic imaging instead ofacquiring multiple DSA incidences, which givesa potential for X-ray dose and contrast mediareduction. The re-stenosis is treated by an in-stent re-dilatation (fig. 9) using a 7 mm balloonwith satisfactory results (fig. 10).

BackgroundThe CHU La Timone at Marseille is amongst the first hospitals in Europe equipped with the Innova3100 digital flat panel angiography system. The Innova 3100 system installed by GE Healthcare has a30 cm x 30 cm digital detector designed to perform general vascular and cardiac interventional pro-cedures, and an integrated multi-modality Advantage Workstation.

Flat panel Innova 3D, introduced in 2005, has radically changed the concept of just morphologicalanalysis of vessels and moved closer to CT imaging, with un-subtracted cross-sectional display ofsoft-tissue, bone, plaque, thrombus and devices as well as the typical volume rendering of vessels.

Innova 3D is useful for planning selectivecatheterization and analysis of fistula angioarchitecture. It is also used post-procedure toverify the embolization success.

Case 2 : In-stent restenosis of the brachio-cephalic trunk

defined using the Innova 3D images. Themicro-catheter is placed in the fistula and thelatter embolized (figs. 4, 5) using mechanicallydetachable micro-coils of type Detach CoilSystem (DCS) and of type interlocking detach-able coils (IDC).

Fortimedix B.V., located in The Netherlands,is a leading medical device company in thefield of vascular stents. The company hasextensive experience in the field of minimalinvasive device technologies, includingproduct development, manufacture and testing.Fortimedix has also been heavily involved incontract durability testing of vascularstents. It has conducted many vascular stentfatigue tests for several major players in themedical device industry using their uniquein-house built stent fatigue tester in recentyears. Very recently, it has tested severaltypes of stents designed for the SFA.

Set-up of the tests and their clinical rele-vanceDifferent self expanding stents were deployedin test tubes (silicone tube) mounted on afatigue machine as shown in the figure below:

The stents were exposed to a cyclic 70º bend-ing and 22% longitudinal elongation at 3 Hzfrequency. The number of cycles to first strutfracture and to total stent separation wererecorded. The purpose of this test was to assessstent structural integrity over time as a result ofabove loading conditions. This is important, asit is clinically shown in various studies, thatthere is a close correlation between stent frac-ture and restenosis. The SFA is subject toextreme multiaxial forces, and bending andaxial elongation are the two predominatemovements for the SFA stent. ev3 requestedFortimedix to comparison test its latest genera-tion self-expanding stent, PROTÉGÉ® EverFlexTM

, against two leading competitor products.

Independent test results of ev3's PROTÉGÉ® EverFlex stentTM

conducted by Fortimedix B.V.

The resultsThe experience is that most cracks occur at thesides of the stents, where the composite loadcase of bending and stretching results in thehighest tensile stress. In these tests, the bestresistance against fatigue failure was achievedby the EverFlexTM stents, which did not fractureup to 193.000 cycles under these extreme load-ing conditions. As a comparison, test samplesof the other two stents in the test fracturedbetween 5.000 and 27.000 cycles. Most likely,this is due to the innovative stent design andthe mechanical properties of the stent materialwhich allows the maximum and alternatingstress/strain level in the EverFlex stent designto be the lowest among the three stents whichwere tested.

Special Edition / CIRSE 2006 - Rome

10 Advertorial Monday, September 11, 2006

Why does the EverFlexTM design have thebest fatigue performance? New spiral connection node configuration pro-vides greater flexibility and vessel conformabili-ty. In addition to this, the new three-wave peakdesign distributes stresses more efficiently andevenly.

What were the conclusions?In bench tests, the PROTÉGÉ EverFlexTM is five toten times more durable than competitivestents as a result of a revolutionary design.

... does not only offer information for you,but also for your patients?

The "Patient & Public" section of CIRSE's home-page (www.cirse.org) offers easily understand-able, patient-friendly information regarding theprocedures performed by interventional radiol-ogists and related topics such as radiation safe-ty to the non-physician. The section is currentlybeing reviewed and updated in order to adjustit to the present situation patients willencounter in Europe. The procedures are listedalphabetically, according to body parts and

Did you know that CIRSE ...

Keep up to date with the latest developments in Interventional Radiology with CVIR, the officialCIRSE Journal. Published on a bimonthly basis, CVIR offers the latest articles on research, clinicalpractice and other hot topics related in IR. A subscription to CVIR as well as access to its online ver-sion offering the possibility to browse all previously published articles and search for specific topicsis free of charge to all CIRSE Members. If you are interested in becoming a CIRSE Member, pleasevisit us at booth 66.

Cardiovascular and Interventional Radiology(CVIR)

Advertorial

patient categories. All information is given inEnglish and will also be available in Germanshortly.

Encourage your patients to get informed aboutIR procedures by visiting the CIRSE website!The modern, intellectual patient will feelinvolved in the decisions concerning his/hertreatment and appreciate your suggestion.

C RSECardiovascular and Interventional Radiological Society of Europe

11The Eternal CityIRnewscongress

Rome offers a unique array of secret placesand forgotten squares. Since they are off thebeaten track, most people fail to discoverthem, missing out on some of the most inter-esting and beautiful places in Rome. Here are afew examples of those little secrets scatteredthroughout the eternal city.

Arco degli Acetari Via del Pellegrino 19-41

The name of Arco degli Acetari or "VinegarMakers' Arch" probably comes from sellers ofvinegar water formerly offering their product inthis area. Once you pass the small arch and comethrough the short, dark alleyway, you will findyourself in a square in which time seems to havestood still. The courtyard is closed on all four sidesby picturesque red houses that have kept theirmediaeval look until today.

Although located in the centre of the city, italmost looks like a country courtyard with catssleeping on the stairs, flower-covered balconiesand wooden carts. In summer the people living inthe houses surrounding the square often bringout tables and chairs to enjoy their dinner al fres-co. The square can only be accessed through thearch and cars cannot go in. Clothes hang from thewindows and the smell of cooking wafts throughthe air. The traffic and pollution of Corso Vittorioand the hustle and bustle of Campo de' Fiori arejust a stone's throw away, but seem like a wholedifferent world to those enjoying the peace andquiet of Arco degli Acetari.

The architectural layering of San ClementeBasilica Piazza di San Clemente

The Basilica of San Clemente dating back to the12th century AD is located only a few metersfrom the Colosseum and is thought to owe itsname to Pope St. Clement I. Apart from being abeautiful church, less well known than it deservesto be, is also a spectacular example of architectur-al layering.

In 1857 excavations carried out under the churchand directed by the prior of the Irish Dominicans,Father Mullooly, revealed the existence of anotherbasilica under the one we can see today. Thatbasilica was in turn built on top of another largepublic building from the 1st century AD and aRoman residence in the courtyard of which a

small Mithraic temple was found. Further excava-tions led to the discovery of a fourth layer con-taining buildings from the Roman Republic, prob-ably destroyed during the fire set by Nero in 64 AD. The visit of the upper church, which is fullof masterpieces, such as the frescoes and themosaic in the apse or Saint Catherine's chapelfrescoed by Masolino da Panicale and Masacciobecomes an even more exceptional experienceby going down to the lower levels.

The original church is larger, dates back to thesecond half of the 4th century AD and is decoratedwith important frescoes from the 11th century ADportraying the lives of Saint Alessio and SaintClement, as well as the tomb of Saint Cyril. It wasconstructed on Roman buildings that were modi-fied considerably over the centuries. Its oldestpart is made of a series of small rooms with barrelvaults and a wall of tufa blocks dating back to the1st century AD. These rooms were probably part ofthe Zecca (State Mint) of Rome. In the second halfof the 2nd century AD, alongside this building, atwo floored domus was built overlooking an out-side courtyard. Part of the stucco decoration isstill visible on the vaults of some rooms. In the 3rd

century, part of this house was transformed into aMithraeum, a sanctuary to the god Mithras. Manyopenings were closed, an altar was built, as werea niche for a statue of the god and a starry vaultto make the place cave-like by keeping with thewhole nature of this underground cult. The fillingmaterial has been removed and the Mithraeumwas restored on several occasions. It is mostlyintact and can be visited.

The Canova-Tadolini Workshop - In the intimacy of a great sculptorVia del Babuino 150

Another tip for those who like to leave the beatentrack when traveling is the recently openedrestaurant/museum created inside the studio ofthe famous sculptor Canova. For years Canovaworked with Adamo, his most talented studentand spiritual heir in this small and curious two-storey construction located in a part of the citythat is traditionally animated by artists' work-shops. In 1818 Canova left the workshop to hisfavorite student. Canova gave Adamo variousassignments and the task of reproducing his mostfamous works. The Tadolini family remained inpossession of the workshop in Via del Babuino forfour generations until 1967, handing down theart of sculpture from father to son.

Today the striking space of the Canova Workshop,which restoration work has left almost intact,houses a small, refined restaurant and a bar. Don'tmiss the chance to enjoy an exquisite dinner oreven just a simple coffee while sitting amongstmarble and bronze sculptures, tools of the sculp-tor's trade and plaster models of statues whichare now scattered in museums all over the world.Everything is laid out in the appealing disarraytypical of workshops. The elegant neoclassicismof Canova and Adamo is combined with the moreromantic style of Scipione and Giulio, as well aswith the more intimate mode of Enrico, every-thing blending into a harmonious ensemble.

Secrets of Rome

The order of Malta's keyhole and a surprisingviewPiazza dei Cavalieri di Malta

The Piazza dei Cavalieria di Malta (Square of theKnights of Malta) is surrounded by palm trees,cypress trees and imaginative walls full of rodsand obelisks designed by Giovanni BattistaPiranesi. The monumental entrance of the head-quarters of the Priory of Malta, which seems tohide a mysterious and untouchable world, offersa surprising detail on its outside. By placing youreye to the keyhole of the main entrance, thecupola of Saint Peter's Basilica appears in a sur-prising manner, framed by a green tunnel ofclimbing plants that is formed by the path of theinside garden.

The Grand Prior Giovan Battista Rezzonico com-missioned Piranesi to arrange the area, belongingto the Sovereign Order of Malta. The architectalso totally transformed the church of Santa Mariadel Priorato, a simple chapel built in the 16th cen-tury. Its origins date back lo the 10th century,when, under the name of Santa Maria Aventina, itwas part of a Benedictine abbey dedicated toSaint Basil of Cappadocia. In the 12th century theabbey passed onto the Templars and, at thebeginning of the 14th century, to the Knights ofRhodes and then of Malta. The inside was entirelycovered in white stucco, designed by the artist.The façade in the fantastic Piranesian style is infact the only architectural work - apart from thepiazza- that was carried out by Piranesi himself.

Doll's Hospital - SquatritiVia di Ripetta, 29

On the corner of Via di Ripetta and Via delVantaggio you can find Squatriti, the artisticrestorers' shop. The grandmother of Federico, theyoung man who still works here today, openedthis strange workshop in 1953, where initiallyonly vases from archaeological excavations andpainted Italian ceramics were restored untilFederico's father branched into new activitieswith his wife, who began restoring fans and dolls.Today it is mostly because of the dolls that thisplace attracts the attention of passers-by. Theshop is tiny and you instantly have the feeling ofentering a timeless place. Federico and his mother work intently at two small countersaround which there is hardly any room to walk.Objects fill the shelves, most of the floor and eventhe ceiling: vases, Italian ceramics, items madefrom ivory, wax, papier-mâché, plaster, porcelainand marble, but above all lots of dolls piled up inthe shop windows, giving this workshop theatmosphere of an old horror movie.

From 1960 onwards, only porcelain or cellulosedolls were repaired, and once industrial plasticdolls were introduced these earlier dolls becamecollectors' items. Even if you have nothing to berepaired, it is worth your time glancing aroundthe shop and meeting the owners.

Santa Maria degli Angeli - A sundial 45 meterslongPiazza della Repubblica

Santa Maria degli Angeli (Our Lady of the Angels)is a majestic basilica built in the Diocletian Baths,initially based on Michelangelo's designs andlater on those of Vanvitelli. On the floor of thebasilica in front of Diaz's tomb, one can admire abeautiful sundial measuring 45 metres in lengthcalled the Linea Clementina or Clementine Line,named after Pope Clement XI who inaugurated itin 1702. This beautiful bronze and marble inlaywas getting rather worn out after centuries ofbeing tread on, but restoration work carried outin 2000 rendered it all of its former beauty.

In order to check the correctness of the Gregorianreform of the calendar around 1700, PopeClement XI asked the mathematician andastronomer Francesco Bianchini to build a monu-mental sundial that would indicate the SpringEquinox and therefore help to determine theexact date of Easter Sunday. According to therules given by the Fathers of the Council of Nicea,Easter was to be celebrated on the first Sundayafter the first full moon following the SpringEquinox. Therefore it was extremely important toavoid mistakes that would have inevitably movedthe dates of all the other mobile religious holi-days.

Along the sundial there is an old marble inlay rep-resenting the signs of the Zodiac. These werebased on Maratta's drawings, using the images ofBayer's "Uranometria Nova." To the right of the line you can see the signs ofsummer and autumn constellations, to the leftthose of spring and winter. Every day of the yearat noon the sun, entering the building throughthe centre of the heraldic coat of arms of PopeClement XI, touches a different point of the line,from Cancer during the summer solstice toCapricorn during the winter solstice and viceversa.

IR Congress News is published as an additionalsource of information for all CIRSE 2006 atten-dees. The articles and advertorials in this newspaperreflect the authors' opinion. CIRSE cannot acceptany responsibility regarding their content. If you have any questions regarding this publica-tion, please contact us at info@cirse.org

Managing Editor: Petra Mann, CIRSE Office

Advisory Board: Andy Adam, Mario Bezzi,Johannes Lammer, Michael Lee, Jan Peregrin, Jim Reekers, Ernst Peter Strecker