Download - Hydrocephalus and Neuro Shunting
Hydrocephalus and Neuro Shunting
Sales TrainingApril 2001
Hydrocephalus: From the Greek
word hydro (water) & cephalo (head).
A pathological condition where there
is a disturbance in production,
circulation and/or absorption of CSF,
with subsequent accumulation of CSF
in the fluid-filled compartments of the
brain (ventricles).
About CSF (Cerebrospinal Fluid)
Clear, colorless fluid Bathes, nourishes & protects brain and spinal cord. Average CSF production-20ml/hr adults and 8ml/hr children 400 to 500cc produced daily contains 15 to 45mg/100ml protein,some
glucose, salts, urea and WBC’s
Ventricular System
Fluid filled cavities deep in cerebrum w/ pressure of 120-180mmH2O
Four ventricles 2 Lateral Third Fourth
Connected by Foramen of Monro Aqueduct of Sylvius
Choroid Plexus Very vascular Found throughout but
mostly in lateral Responsible for ICP
waveform/
follows arterial pulse
Brain Layers/CSF Absorption
A. - Arachnoid A.G. - Arachnoid Granulation B. - Bone C.A. - Cerebral Artery C.V. - Cerebral Vein D. - Dura Mater F.C. - Falx Cerebri P.M. - Pia Mater S. - SkinS.A.S. - Sub-Arachnoid SpaceS.D.S. - Sub-Dural SpaceS.S.S. - Superior Sagittal Sinus
CSF Flow-path CSF flows in a caudal direction
through the lateral, third and fourth ventricles
Exits through foramina of Luschka and Magendie into subarachnoid space around spinal cord and brain.
Absorption occurs through the arachnoid granulations into the venous system.
Types of Hydrocephalus Communicating Non-communicating or Obstructive Normal Pressure Hydrocephalus Congenital Acquired
Normal CT Scan CT Scan Showing severehydrocephalus
Etiology of Hydrocephalus
Communicating Overproduction/underabsorption of CSF Choroid Plexus Papilloma-overproduces CSF SAH Infection Neoplasms affecting the meninges Trauma
Etiology of Hydrocephalus
Non-Communicating (Obstructive) Aqueductal Stenosis Arnold-Chiari Malformation (Cerebellar tonsils protrude into
Foramen Magnum) Cysts Myelomeningocele IVH Tumors (particularly posterior fossa)
Normal Pressure Hydrocephalus Usually present in elderly Ventricular dilation despite normal CSF pressure Triad of symptoms
1) dementia
2) gait disturbances (usually earliest)
3) urinary incontinence
Signs & Symptoms Associated with HydrocephalusInfants
Increased head size Bulging Fontanels Separation of Cranial Sutures Prominent Scalp Veins Persistent Vomiting Lethargy or irritability “Setting Sun” eyes Seizures Delayed Development
S/S Associated with Hydrocephalus, cont.Toddlers
Increased head size Persistent vomiting Headache Lethargy or irritability “Setting Sun” eyes Blurred Vision Seizures Delayed Development
Hydrocephalus
“SETTING SUN” EYES
S/S Associated with Hydrocephalus, cont.Older Children & Adults
Persistent Vomiting Headache** Visual Problems Lethargy Behavior Changes Difficulty with schoolwork Seizures
Diagnosis
Clinical Evaluation Ultrasound (Intrauterine & through Fontanels. CT Scan MRI
Treatment ModalitiesSurgical Procedures
Remove obstruction (Blood Clots, Tumors) Endoscopic Third Ventriculostomy Septal Fenestrations (Endoscopic) Cyst Fenestrations (Endoscopic) Shunt Insertion
Interventions for HydrocephalusIf untreated:
*50-60% die of complications
If treated:
*40% normal intelligence
*70% live beyond infancy
Questions???
Historical Treatment of HydrocephalousHippocrates recognizes water accumulation in the brain.
1545-Thomas Phaire-1st non-surgical treatment--Herbal plasters, head wraps
18th Century--ventricular puncture--death from meningitis common
1800’s-Variety of materials used to “wick” CSF from ventricles to subarachnoid space (i.e., linen threads, glass wool, rubber tube)
1898-first lumboperitoneal shunt
Historical Treatment of Hydrocephalous, con’t1922-Dandy-third ventriculostomy through subfrontal approach
1923-Mixter-1st endoscopic 3rd Vent., choroid plexectomy (L’Espinasse, Hildebrande, Dandy, Putnam and Scarff)
1950’s-First effective CSF diversion with a one-way valve using biocompatible synthetic materials.
John Holter-1st Silicone Valve Robert Pudenz-Silicone distal slit valve Peritoneum chosen as better absorptive site than the vascular system
Heyer Schulte and Shunt Industry History1953: Dr. Robert Pudenz and W.T. (Ted) Heyer team up on
hydrocephalus research
1955: Pudenz ventriculo-atrial shunt is developed
1959: Rudy Schulte joins Heyer and Pudenz
1959: Pudenz flushing valve is developed
1960: Codman distributes Heyer-Schulte products
1960: Holter valve is created
1965: Cordis begins U.S. presence
1965: Extra-Corporeal buys Holter
1973: Codman dropped as Heyer-Schulte distributor
Heyer Schulte and Shunt Industry History1974: American Hospital Supply buys Heyer-Schulte
1975: Codman introduces their own product line
1977: Anasco, PR manufacturing facility is built
1978: Codman buys Extra-Corporeal
1983: AHS folds Heyer-Schulte into V. Mueller
1984: Dr. Pudenz and Rudy Schulte found P-S Medical
1986: Baxter-Travenol acquires AHS
Heyer Schulte and Shunt Industry HistoryThe 90’s
NeuroCare Group acquires Heyer-Schulte Radionics introduces full shunt line Medtronic acquires P-S Medical Phoenix Biomedical enters the market Codman acquires Cordis Elekta acquires Cordis NMT acquires Cordis Integra acquires Heyer-Schulte
What is a Shunt?A shunt is a device that diverts CSF from the CNS (usually the lateral ventricle or the lumbar subarachnoid space) to an alternate body cavity (usually the peritoneum or the right atrium) where it is reabsorbed.
How Shunts Work Divert CSF from the CNS to another body cavity (R
atrium, peritoneum) for absorption. Mechanical device that regulates flow out of the ventricle. One-way valve opens when the sum of the forces acting
on it exceed some threshold. (the difference between the inlet or ventricular pressure and outlet or peritoneal pressure.
Shunt Systems Ventriculo-peritoneal Ventriculo-atrial Lumbar-peritoneal
Shunt Components
Primary Components Proximal Catheter Valve (Proximal or Distal) Distal Catheter
Optional Components Reservoir Siphon Limiting Mechanism (ASD, SCD, GCD)
Accessories Connectors Guides Introducers/Stylets Catheter Passers
SHUNT ACCESSORIES Proximal catheter stylet (can use endoscope) Stylets for unitized shunts Shunt passers Connectors and Right angle guides Shunt tap kits Manometers
Valve Mechanisms Differential Pressure Valves Flow regulating devices
Valve Mechanisms Differential Pressure Valves Valves open when difference between the ventricular
pressure and the peritoneal pressure exceeds some threshold.
Pressure difference at which a valve opens is called the opening pressure.
Pressure difference at which a valve closes is called the closing pressure.
Valve TypesBurr Hole - shaped to fit the hole made in the skull.
The reservoir is an integral part e.g. Pudenz
Flat Bottom - rests flat against the skull distal to the ventricular catheter e.g. LPV II, Novus
Cylindrical/In Line - appears “seamless” between the ventricular and peritoneal catheters
e.g.. Ultra VS
Pudenz
Mishler Dual-Chamber
Ultra VS Cylindrical
One Piece Hydro Shunt
Ommaya
Internal Valve Components Slit Ball and Spring Miter Diaphragm
Valve MechanismsSlit Miter
Valve Internal Mechanisms High spring rate valves- open slowly, close quickly
(miter, slit) Low spring rate valves- open quickly, close slowly
(diaphragm, ball & spring, prone to siphon)
Valve Mechanisms
Slit valves - a slit in a curved rubber layer. The flow arriving from the concave side opens slit, size of opening relating to the upstream pressure
Can be proximal or distal
Disadvantage: ”stickiness” of silicone rubber can affect opening Precision? Varies with age of valve?
Slit ValvesCodman
Holter (proximal catheter/valve) Denver (proximal catheter) Accuflo (distal catheter) Uni-shunt (distal catheter)
Radionics Proximal slit valve
Phoenix Holter-Hausner valve
One Piece Hydro Shunt
Valve MechanismsMitre valves - the leaves of the “duckbill” part in response
to the pressure differential. Pressure characteristics of mitre valve are related to size,shape, thickness and length of leaves.
Disadvantage : “stickiness” of silicone rubber can affect
opening
Mitre ValvesHeyer-Schulte
Ultra-VS(cylindrical) Mishler Dual Chamber (flat bottom) Spetzler in-line Lumbar - Peritoneal valve (cylindrical)
Valve Mechanisms
Spring valves/Ball in cone - a metallic spring which applies force to a ball (usually ruby or sapphire) located in an orifice. Opening pressure is defined by spring stiffness
Disadvantage: prone to obstruction from CSF debris or high protein
content subject to siphoning
Ball-in-Cone Valves
Codman Medos Hakim Medos Programmable
NMT/Cordis Atlas Hakim Orbis Sigma II
Sophysa Sophy Programmable
Valve MechanismsDiaphragm valves - a round diaphragm rests on or under
a valve seat. Pressure causes the diaphragm to be detracted from the seat allowing CSF to flow
Disadvantage: prone to siphoning in some designs flow is not laminar making it prone to
obstruction
Diaphragm Valves
Heyer-Schulte Pudenz (burr hole) LPV II (flat bottom) Novus (flat bottom)
PS Medical/Medtronic Delta (Burr hole, flat bottom) Button(flat bottom) Contour (flat bottom)
Radionics Contour Flex Equi-flow Burr hole
Codman Accu-flo valve
Diaphragm Valves
Flow regulating mechanisms Maintains same flow rate at any differential pressure by
increasing or lowering its resistance to pressure May be achieved by a solid conical cylinder inserted inside
a ring attached to a pressure sensitive membrane
Valve Mechanisms
Inner diameter of ring isgreater than largerouter diameter ofconical cylinder
By reducing surfacearea, mechanismrestricts amount of fluidthat can go through
Outer cylinder movesto compensate forreduced surface areato maintain flow rate.
Valve Mechanisms
At very low pressures acts like a DP valve At high pressures the ring moves beyond the central
cylinder to give a “blow off” valve.
Valve Mechanisms
Treatment for Siphoning In a vertical position, negative pressure from hydrostatic
column can cause overdrainage Siphoning control achieved by adding siphon resistive
devices to the shunt system. Functions as a second valve in line that closes in
response to peritoneal pressure
Shunt Failures and Complications Shunt failure is at a maximum in first few months after
surgery (25-40% at one year follow-up). Then falls to 4-5%
The mean survival for a shunt is approx 5 years
Shunt Failures and Complications Shunt obstruction (about 50 - 60% of all failures) Infection(between 5 - 10%) Mechanical failure due to disconnection Valve failure Overdrainage Patient/shunt mismatch
Shunt Placement Procedure Skin Incision Placement of Burr Hole Sbcutaneous dissection Tunnel the peritoneal catheter Open dura & place ventricular catheter Connect valve, test & clean Distal catheter insertion & skin closure
Shunt Implantation Approaches
Occipital Approach Temporal Approach Frontal Approach
Skull of a newborn seen from above Adult human skull seen from above
LamboidalSuture
PosteriorFontanelle
SagittalSuture
AnteriorFontanelle
MetopicSuture
CoronalSuture
Indications For Use of a Lumbar-Peritoneal ShuntCommunicating Hydrocephalus - when ventricles are
small and it would be difficult to cannulate with a ventricular catheter.
Normal Pressure Hydrocephalus - shunting without necessitating a cranial procedure.
Goals of Shunt Design & DevelopmentRestoration of “normal physiology” in the shunted individual
Maximize the potential quality of life for each patient
Expand the population of successfully treated patients
First Generation Diaphragm Valve
Second Generation Diaphragm Valve
Third Generation Diaphragm Valve
Integra NeuroSciencesConsistency by Design
FLOW PATH
DELTA VALVE
LPV II Valve Performanceat High Flow Rates (45.8ml/hr)
LPV Valve Performanceat High Flow Rates (45.8ml/hr)
LPV II Valve Performanceat Low Flow Rates (4.6ml/hr)
LPV Valve Performanceat Low Flow Rates (4.6ml/hr)
Competitive Matrix Medtronic P.S. Medical Cordis Codman Radionics Sophysa Phoenix
Flat Bottom Diaphragm Competitive MatrixManufacturer/
Brand Name Valve
Mechanism Shape Reservoirs ASD Catalogue # Pricing Other
Heyer-Schulte/Novus
3rd Generation Diaphragm "T" Valve
Flat Bottom Proximal, Integral
Yes Normally
Open
NL850-9010 series depending on pressures and
sizes (standard & mini)
$665.00 valve only
$765.00 kit
PS Medical/ Delta
2nd Generation Diaphragm
Flat Bottom Proximal, Integral
Yes Normally
Closed
42812 series (small)
42822 series (standard)
92822 Regular w/BioGlide
92812 Small w/BioGlide
$730.00 valve only
$840.00 kit
$820.00 valve only w/BioGlide
Snap Reservoir Option
Radionic's/ Equi-Flow
2nd Generation Diaphragm
Flat Bottom Proximal, Integral
Optional SLR-L, SLR-M (standard)
SLS-L, SLS-M (small)
$630.00 valve only
$780.00 kit
Only available in low and medium pressure
Codman J&J not available
N/A
Cordis NMT not available
N/A
Cordis NMT/ Orbis Sigma II
Ball and Spring
Flat Bottom 909-612 $675.00 valve only
$745.00 kit
No peritoneal catheter
Flow specified not really equal to others but the Orbis Sigma is
their top line valve
Manufacturer/ Brand Name
Valve Mechanism
Shape Reservoirs ASD Catalogue # Pricing Other
Heyer-Schulte/ LPV II
3rd Generation Diaphragm "T" Valve
Flat Bottom Proximal, Integral
No NL850-9810 series depending on sizes
(standard and mini) and pressures (high, medium, low)
$450.00 valve only
$595.00 kit
PS Medical/ Contour
2nd Generation Diaphragm
Flat Bottom Proximal, Integral
No 42419 series (small)
42322 series (standard)
92322 Regular w/BioGlide
92312 Small w/BioGlide
$445.00 valve only
$505.00 kit
$525.00 w/BioGlide
BioGlide---
catheter coating
Radionic's/ Contour-Flex
2nd Generation Diaphragm
Flat Bottom Proximal, Integral
Yes CFR-L, CFR-M, CFR-H (standard)
CFS-L, CFS-M, CFS-H (small)
$400.00 valve only
No kit available
Codman J&J not available
Cordis NMT not available
Flat Bottom Diaphragm Competitive Matrix
Burr Hole Diaphragm Competitive MatrixManufacturer/ Brand Name
Valve Mechanism
Shape Reservoirs ASD Catalogue # Pricing Other
Heyer-Schulte/Pudenz
3rd Generation Diaphragm "T" Valve
Burr Hole (12mm and
16mm)
Distal, Integral No NL850-1330 series depending on size and
pressure
$279.00 valve only
Heyer-Schulte/Pudenz
3rd Generation Diaphragm "T" Valve
Burr Hole (12mm and
16mm)
Distal, Integral Yes NL850-1410 series depending on size and
pressure
$569.00 w/ASD
valve only
PS Medical/ Delta Burr Hole
2nd Generation Diaphragm
Burr Hole (12mm and
16mm)
Proximal, Integral
Yes 42832 series (12mm)
42842 series (16mm)
92832 12mm w/BioGlide
92842 16mm w/BioGlide
$670.00
$765.00 w/BioGlide
Snap Reservoir Option
PS Medical/ CSF Flow
Control Valve
2rd Generation Diaphragm
Burr Hole (12mm and
16mm)
Proximal, Integra
No 42542, 42544, 42546 Low, medium, high
pressure
$290.00 valve only
Radionic's/ Burr Hole
2nd Generation Diaphragm
Burr Hole (12mm and
16mm)
Distal, Integral No BHV-12L or BHV-16L Series depending on
pressure
$270.00
Codman J&J Accuflow
2nd Generation Diaphragm
Burr Hole (16mm only)
Distal, Integral Optional
Neonatal Valve Systems Competitive MatrixManufacturer/ Brand Name
Valve Mechanism
Shape Reservoirs ASD Catalogue # Pricing Other
Heyer-Schulte/Ultra VS
Miter Valve Cylindrical Optional, Proximal
No NL850-1126 series depending on size and
pressure
$375.00 valve only
$625.00 kit
PS Medical/ Ultra Small
2nd Generation Diaphragm
Flat Bottom Optional, Proximal
No 42410 series depending on pressure
$405.00 valve only
$625.00 kit
Snap Reservoir Option
PS Medical/ Button
2nd Generation Diaphragm
Flat Bottom Optional, Proximal
No 24003LL series
$365.00 valve only
$580.00
Codman J&J N/A
Cordis NMT/ Omnishunt
Neonatal Valve System
Ball and Spring
Cylindrical Optional, Proximal
Optional 908-222 series
908-322 series
908-344 series depending on size and
pressure
$475.00 Gravity Compensating
Accessory
46544
Product line strengths
Consistency and predictability Broad product line Clnical support History Manufacturing expertise Pricing flexibility