Diag Img III Fall 05 1 of 29Dx Imaging III- Kettner

9/12/05

RSNA.org: Education Portal-Databases and Teaching Files (search Google for case studies)www.rad.washington.edu/ (online teaching materialsanatomy, musculoskeletal cases)

C/S Normal Anatomy

Factors for attracting trauma: -↑ ROM = ↑ risk for trauma (MVA) -↑ transitional ROM areas (T/L junct, etc)(Most mobile joint = glenohumeral jt)

C/S xray series: APOM, neutral Lat, APLC (min of 3)-5 view = obliques-7 view (Davis Series)= flex/ext

Criteria for accepting films:1. All anatomy present: Base skull, occiput, inf endplate of C72. Contrast: ability to see cortical and medullary detail3. Soft tissue visibility: see w/out a hot light (pre-vertebral and post-cervical tissues)

Method of evaluating C/S films (search pattern)1. Soft Tissue:

Pre-vertebral: check for swelling - impact trachea/pharynx (aerodigestion) compromise affects GI and Resp system

-3 categories occupy pharyngeal space: Hematoma, malignancy (smoking), retropharyngeal abscess

Post-cervical: rarely any findings-Nuchal lig may calcify simulate fracture of SP

2. Osseous Structures: Vertebrae: VB and posterior elements

1. C1: arch, post/ant tubercle2. C2, C7 very prominent SP3. C2 – transverse foramina angles down steeply (VB “bullet hole” appearance)4. C3-C7 uniform in appearance5. Transverse process 6. Pillar- attached to VB by the pedicle (“foot”) – oblong structure directly behind

-Commonly missed fracture (forced extension)- m/c C2 or C6/7

3. Joints: ADI (<3mm adult; <5mm kids to 12 yo)

Diag Img III Fall 05 2 of 29-Cause for ↑: RA, Down’s Synd (20%), Trauma

+Sero - : AS, psoriatic, reiters-Laxity of Transverse lig and trauma: Posterior arch hits spinal cord hematoma myelopathy (cord & marrow- error in naming)-Clin. Presentation of myelopathy: (UMNL)

Minor = pain, ↑ DTR, ↑ tone, spastic paresis, pathologic reflexes # jts in C/S: IVD, apophyseal (aka: Z-jt), uncovertebral (rigid bone up the back of VB; aka= co-

lateral, luschka jt), atlanto-axial at ADI (Discogenic) Spondylosis: involving endplate (m/c in lower C/S)

-Accompanied by ↓ IVF (Narrow IVF from sup to inf = take out disc space (thickness of disc keeps IVF in maximal vertical dimension)-Disc space narrows w/ age but the disc itself fibroses and gets larger micro-fracturing of the endplate produces curved endplate

+Cause: trauma, aging+Compression neuropathy likely because IVF narrowing (C/S nerve root exits above VB in C/S)

APLC view:Soft tissues:

1. Pulmonary apices (bronchogenic carcinoma-smoking) arm/neck painPancoast syndrome: tumor invade brachial plexus (S/S = )

Metastasis above T1= ablation of sympathetic chain create Horner’s Syndrome (result) … (pseudomotor gland/sweat ↓= mydriasis, miosis, ptosis = weakness of palpebral mm)

Horner’s can occur from whiplash or idiopathic2. Trachea (deviation) – usually incidental finding

Pushed in: goiter, tumor (thyroid cancer), 3. Vascular structures of the neck: calcification of bulb of carotid artery or lymph nodes

(atherosclerosis until proven otherwise)Osseous:

1. Pedicle, SP (bifid), VB, uncinate process (grows w/ degeneration and ↓ disc space), Joints:

1. Can’t see apophyseal jts because angled at 45◦ 2. See IVD3. ↓ Cervical curve due to ↑ size of pillars (if is reversed = always abnormal)4. Anterior head carriage: compensate by putting torque of L/S

Flexion/Extension: intersegmental ROM (Penning Technique) – can have normal gross ROM w/ abnormal interseg. ROM

Alter density w/ neck flexion (↑ thickness of neck) Retropharyngeal and retrotracheal msrs Torn ligaments = spinous fanning (SP too far apart) Hard palate (above is maxillary sinus)- soft palate and uvula behind hard palate

Fractures:3 Dens fractures: 1. Tip (least problematic) 2. End (m/c) 3. Intro-body fracture: dens & part of VB is broken off

Vertical dens fracture = very rare (probably space btwn teeth)Check to make sure dens is vertical: if tilted > 3◦ = have fracture

Diag Img III Fall 05 3 of 29Check lat. Masses: symmetrical space to densCheck sup. end plate of C2: fracture

C/S Obliques: tube tilt because of IVF angled down at 15◦ Anterior films are “true”: show same side IVF (caudal tilt) Posterior: shows opp IVF (cephlad tilt) Normal anatomy: large C2 IVF

-If other IVF’s big: could be neurofibroma (NR tumor)-Shingle like Pillar facets-Id both pedicles (over VB and IVF)-C1 post/ant-Skull: inner and outer table of skull (space btwn= diploic space)

-contains hematopoetic tissue in diploic space (not present below EOP)

L/S:Soft tissue:Anterior:

1. Abdominal Aorta: look for atherosclerosis (calcification) if parallel if bulged = AAA(abdo aortic aneurysm)

Posterior:1. Not much soft tissue

Bones:Sacral canal = nerve roots S1/5Conus medullaris: termination of spinal cord at L1/2IVF: preserved by disc spacePedicleSacral anatomy

Joints: IVD, apophyseal jt1. Apophyseal jt: sup & inf facet

-AJA: apophyseal jt arthrosis-

Cases (online):1. Pelvic fractures: crack front – break sacrum also (back); B/L sup/inf pubic rami fractures

Fracture= Cortical discontinuities as well as areas of ↑ density where the bone fragments are overriding-Ring bone rule: if see fracture-largest fracture hurts the worse

9/19/05

Diag Img III Fall 05 4 of 29

OA Model: Break down of cartilage: no blood, no innervation

How does it survive? = diffusion (balanced movement of jt)Risk Factors:

Too much movement:Repetitive injury: jt not stable (lig instability)Soft tissue injury leads to jt instability (cartilage suffers)

Too little movement:Obesity: cartilage disappears (no nutrition)

Primary OA is genetic (Secondary due to wear and tear)

Nociception = tissue damage (can occur w/out pain) Pain = 2nd order neuron to thalamus = perceives pain (can occur w/out nociception) Chronic pain: factors which are affective (emotion) and cognitive (expectation and attention)

-Brain makes situations for us from expectations (“pos vs neg thinking”) – NS shapes their prognosis-Emotions: flare ups of conditions can occur because emotions lower pain thresholds-Headaches are chronic pain

Glycosaminoglycans (GAG): nutritional support for cartilage-ex: chondrotin sulfate-Enzymes that break down GAG’s = from pain mediators

Diag Img III Fall 05 5 of 29Repair process: matrix synthesis & cell proliferation (↑ density on Xray = evidence)Mechanism of cartilage damage:

Soft tissue should distribute force thru all cartilage loss of cartilage due to imbalance of force

Sub-terrain cracks communicate to surface piece of cartilage “falls off” Synovial fluid injects thru cracks into subchondral bone (cysts) www.isakos.com/innovations/degknee.aspx

Slide Micrograph of bone: Trabeculae: tensile strength of steel (light pink stain- stain according to age/stress = Wolff’s

Law)-Bone will adapt to changes in forces applied to it-Yasuda Study: bone bent in a vice, placed electrodes into bone polarity differences found as a function of the bone stresses (concave side pos= ↑ osteoclasts activity; and convex side neg = osteoblast activity)

Piezoelectric Effect: compressing crystals (DNA) will provides electrical current (deformation of bone)

-Put hands on patient = activate these currents on tissues compressed-MRI: msr electromagnetic field (can we msr electrical currents in tissues?) pathology as an electro-magnetic component

Scoliotics change density as a function of the distortionHealing of fractures: get back bone that is identical to original bone (not stronger)Soft tissues don’t heal/repair as well: Location of OA: wherever the axial jts occur (knee, hip, spine)-GH jt is uncommon (AC is common site = result of scapulo-thoracic mechanics)4 jts of Shoulder: GH, AC, SC, Scapulo-thoracic

Patellar tracking dysfunction leads to OA of kneeBunyon: 1st metatarsal/phalangeal jt (common site of OA)

Symptons of OA: Jt pain associated w/ movement Limitiaon of motion Stiffness after periods of rest Referred Pain

Signs of OA Limitation of motion Changes in shape of jt (osteophytes) Malalignment (degenerative subluxation) : jt cannot maintain normal position w/out normal

quantity of cartilage changes ROM-Medial knee compartment = genu valgus-Coxa (hip)

Degenerative Instability (no articulation because jt is so damaged) Spasm or atrophy of surrounding mm (stop using the jt due to pain) Fine crepitation on jt motion: sounds like sand (osteochondral pieces)

-Gross crepitice = clunking soundDJD of C/S: see disc space narrowing (discogenic spondylosis)

-Spondylosis deformans = minimal narrowing-Uncinate process enlarges and scleroses (uncovertebral arthrosis) erodes into vertebral body (↓ disc space = transfers forces to uncovertebral jt)

Diag Img III Fall 05 6 of 29-↓ IVF due to disc space narrowing (Hour glass shape from bone growing into IVF)-Apophyseal jt arthrosis (AJA): degeneration of sup/inf articulating processes (m/c in L/S)-Neurologic damage can occur: Central canal compression (myelopathy – UMNL)Radiculopathy & myelopathy both present-Physiologic fx is related to anatomy (psychosocial also related)

Flex C/S view:-Clinically normal ROM if flex chin to chest all ROM coming from C4/5 because dysfunction below

Ext C/S view: no movement below and moves too much above dyscogenic spondylosis

Left arm pain from heart (referral)Slipped capital epiphysis refer pain to knee &/or hipAlways evaluate above & below the joint

9/26/05How do degenerative processes affect function?Generalized: as fixation occurs in lower C/S, there is at least one segment above that should be hypermobile (C3)

Occurs w/ surgical fusion as well post-sx cervicalgia Don’t know whether treating fixed segment will resolve hypermobility Penning Method of Measure: copy flexion film on to (14X17), then overlap ext film onto C7

and use edge as a ruler and draw line (continue to line up each C-vertebrae and make lines of edge of film msr angles made by the lines) = plot intersegmental ROM

Diag Img III Fall 05 7 of 29When seen in young patient:

Klippel-feil Syndrome: multiple congenital blocked vertebrae, therefore ↑ mobility on otherwise normal discs (↑ degeneration even at 25 yo)-Short hair-line

MRI: Wasp waste vertebrae – congenital block (failure of somites to separate)-Fusion = (arthrodesis) only when there is surgical involvement (complication: excessive bone w/in the canal – post-op stenosis 2◦ to fusion)-Also see HNP at above level, compressing Spinal cord (extra-dural compression)

Congenital Stenosis: laminae are not present (pillar is on spinolaminar line)-Space for the cord is too small (i.e; compression gives 4 Quadrant Lhermittes sign!!)-Mensuration: msr AP diameter of body, then msr from back of body to spinolaminar line-If stenosis: canal ratio is smaller (if < 82) – normal canal is 1:1 (100)

Ossification of PLL: Large bone bar w/in the canal – pushes the spinal cord out of the way (compression causes Lhermittes Sign)-Can compress cord up to 18% diameter (slowly) and patient remains asymptomatic.-Problem is trauma can transect the cord-Know about DISH: DM II correlation (test glycosylated hemoglobin) & ↑ incidence of OPLL-Cord Compensation: “share stresses” – rewire functionally/structurally

Facet inside the neural foramen (noise of position and rotation) – not spondylolisthesis Spinal stenosis: Growths into the Lat recess, neural foramen, or central canal (>55 yo)

- Outcome same w/ conservative care vs surgical tmt- Outstanding features: hate extension (buckle ligaments – compress dura) bend

forward, tension placed on tension on PLL and Flavum = ↓ compress (have both +/- for neurologic signs = diff day to day)

Flavum ossification: becomes continuous w/ apophyseal jt capsule (↑ symptoms) see at post, inf/lat portion of canalSAF (superior articular facet) is border forming w/ the neural foramen

Rostral/caudal subluxation: degenerative sublux that happens every time there is disc thinning (alter alignment of facets)

L/S: apophyseal jt arthrosis == create back pain (much more than discs)HNP: (<50 yo) broad base wider than the AP diameter = protrusionIf longer in AP diameter than the base= extrusionSequestration = separate from the rest of the disc

Disc bulge: 50% diameter of the VB (not clinically significant)Look at paper in library: IVD Derangement

Lower extremity DJD: affect fx of cardio-pulmonary systems (↓ activity) The reduction of radius of activity: ↓ w/ ↑ degenerative pain (non-ambulatory) For every yr of life = loss of 1% cardiorespiratory fx 1◦ challenge of elderly care = maintain mobility!! As radius of activity ↓ = ↑ isolation (↓ social activity) lead to depression

Degenerative Jt Ds: Loss of cartilage

o Causes migration (femur moves sup) due to loss of cartilage (i.e; degenerative consultation)

o Chondromalacia: softening patella (young person w/ knee pain – tracking abnormality due to muscle imbalance)

o Patellofemoral arthrosis

Diag Img III Fall 05 8 of 29 Fabella: sesamoid bone in posterior knee

Osteophytes: blood supply to cartilage (re-vascularization) or by force (transforming cartilage to bone)

o Buttressing: thickening of cortex due to ↑ stress (Wolff’s Law)o Genu Varum: tibia rotates medially (valgum – rotate laterally)o Equine varum/valgum (ankle)o Cubital varum/valgum (elbow): male carrying angle almost straight, female angle

(valgus) 10-15◦ o Coxa varum/valgum (hip)

Sclerosis: attempt at repair Irregularity, subchondral cysts THA: total hip arthroplasty: resection of proximal femur and metallic replacement

o Indicated if not responding to care and fx declining (clinical decision)Meds: NSAIDs and aspirin ulcer, damage liver

Synovial Chondrometaplasia (aka, synovial chondromatosis) Metaplasia: Transform 1 tissue into another as protective mechanism Metaplasia dysplasia neoplasia See joint mice: osteochondral fragments (synovium cartilage bone) M/C cause is OA (secondary condition – fewer # of particles)

o Primary condition = tumor (↑ # of particles) Burned out RA (osteopenic) becomes OA (↑ bone = sclerosis)

o RA tmt w/ steroids = affect on bone (produce embolism ischemic necrosis; also ↑ caliber of bone, osteopenia, DM, etc)

OA of the Wrist: ↓ radiocarpal jt space, pointing of the radial styloid process Occupational hazard: pneumatic hammer (jack hammer syndrome); Pipe fitters (repeated

pronation/supination) Post-traumatic OA

OA in base of thumb = Trapezium-1st metacarpal jtDestabilized ligaments….

10/3/05

Charot’s Joint: 3rd phase of Syphilis – spirochete takes residence in the spinal cord cause spinal hypermobility w/out painful symptoms (aka neuropathic joint ds/arthropathy)

Destruction of afferents: don’t feel pain, joints become lax no protection to everyday activity = lead to unstable joints

6 D’s of Charots Jt1. Destruction of articular surfaces2. Debri resulting from destruction3. Dislocation: loss of articular congruency4. Density ↑ (opaque)5. Distention of joint capsule (swelling)6. Disorganized joints

Xray appearance of a joint that has “exploded by dynamite” and pt has no pain!!!! (knee, hip, spine for syphilis)

Appear in the foot: attack tarsals, inter-tarsal joints (etiology= alcoholism, DM) Seen in elbow: capsule laxity cause dislocation When foot = ETH, DM

Diag Img III Fall 05 9 of 29 When knee, hip, spine = Tabes Doralis (dorsal horn) – syphilis Shoulder (sometimes elbow)= Syrinx (fluid is inside the spinal cord from destructive lesion)

o Syringomyelia: fluid in cord (congenital)o Syrinx: severe trauma to C/S (liquification necrosis of neural tissue)

Deafferentation (reduction of sensory input) Dys-afferentation (jts abnormally mobilized will go thru this state) = reduction

of normal sensory input due to immobilization (could also have ↑ from hypermobility)

Study: casted broken ankles, pts underwent TMS (trans-cranial magnetic stim)

o Tib anterior- stim in motor cortex w/ TMS before casting (volume mm responding to stim ↓ during immobilization)

Phantom limb syndrome: cortex still “remembers” the proprioceptive input of the limb after amputation

Neuroplasticity: brain capable of changing to meet environmental demands (even after childhood) new research in NS rehab

o Study: placed low/high alternating currents into stump of amputated limb (sensory discrimination task) pt ask to say which current it was over a period of therapy time

Result: ↓ opium meds taken, ↓ phantom pain

Cervical Spine Trauma:

Pediatric Anatomy: Vertebral Endplates are slanted (no 2nd ossification centers yet = teens) ADI = 0-5 mm (ligament laxity – physiological hypermobility of upper C/S) <2 yo: during expiration phase, develop “mass” in retropharyngeal space toward anterior Flexion: see normal mobility in C1/C2 (post tub goes sup, stays still, or goes inf) Pseudo-subluxation of Childhood: reference to the apparent injury of C2/3 w/ offset = normal

finding!! (spinolaminar line intact)o George’s line gives lots of false positives = use spinolaminar line always!o If do have anterolisthesis = see break in spinolaminar line

CT Anatomy: axial slices Rule of Steele (rule of 3): space occupied 1/3 by dens, 1/3 by cord, 1/3 by space

o Space (7mm): half in front of cord, half behind cord Uncinate process: see ridge of gone behind VB (hypertrophy narrows the IVF)

o Foramen transversarium: vascular foramen (can be compromised by uncinate arthrosis also) =

o Therefore: uncinate arthrosis can cause Neuro-vascular compression symptomsCTM: CT Myelogram (contrast agent injected thru dura mater see opacity of sub-arachnoid space

o Extra-dural defect: appears outside of spinal cord (evidence of disc herniation)o Resulted in cord compression? Not if still see space between dura and cordo See distinction of cord (black) and CSF is white around (looks like a mote around the “castle”

= cord)o See same on T2 weighted MR

o Cord enlargements: cervical and conus medullaris (axons for upper/lower extremities)o Axillary pouch: last pt there is CSF and end of dural tissue before get to peripheral NS

MR

Diag Img III Fall 05 10 of 29Cervical Trauma: multi-system connection

- Neural tract to brain = cord- Vascular tract to brain = vessels to heart- Osseous tract to brain = vertebral column- Airway tract = Pharynx/trachea- ABC: airway, breathing, cardiac (emergency C/S trauma procedure)

Pre-vertebral hematomas are life threatening Retropulsion: explosion of VB sending fragment back into canal (traumatic

extradural compression) great risk of spinal cord injuryImaging Objectives in C/S Trauma:

Detect and assess the extent of osseous, ligamentous, neural, and other soft tissue injuries (disc, vessels)

Assess stability of the injured spine (always assume instability w/ unconscious patient – move C/S w/ entire body)

Is xray good screen for C/S trauma?o Over 93% sensitivity under ideal conditiono CT used only for special caseso Drawbacks of plain film

Difficult to interpret – significant experience requiredSome authors reported high rate of diagnostic errors

Fractures Which Are Most Commonly Missedo Odontoid process 25%o Articular facets 14% (C5/6)o Hangman’s fractures 10%

Classification by mechanism of injury:o Mean injury vector (MIV): characterization of the trauma mechanism (Hx designed to

predict where fracture is located due to mechanism)

Flexion Injuries:Subluxation (ST) Stable

Dislocation in facet jts (locked facets)U/L (ST) StableB/L (ST) Unstable

Odontoid FracturesType 1: dens tip StableType 2: dens base UnstableType 3: dens w/ body StableWedge Fracture StableClay-shoveler’s Fracture (SP stress fracture at T1, C7)

Stable

Teardrop fracture: piece breaks off (paraplegia)

Unstable

**Soft Tissue injury: Flavum nucha, PLL, etc

Extension Injuries:Fracture of Post arch of C1 StableHangman’s fracture (traumatic spondylolysis)

Unstable

Diag Img III Fall 05 11 of 29

Compression Injuries:Jefferson’s fracture (C1) UnstableBurst fracture (VB comminution >2 fragments at fracture site)

Stable

Miscellaneous Injuries: (use CT for final dx)Rotatory dislocation/fixation (torticollis that doesn’t respond)

Stable

Pillar fracture (hard to see on plane film) – whiplash that doesn’t respond

Stable

10/10/05I. Anatomical Defn’s of Instability: term defined w/ radiography!!!**”Loose tooth” idea: see on neutral, resets on extension (disappears)Stable vs. Unstable:

Stable: Can withstand stresses w/out progressive deformity or neurological abnormalities Unstable: Can lead to ↑ deformity or ↑ neurological deficit or both under normal stresses

o Instability on a lateral cervical spine; look for: 3.5 mm horizontal translation of one vertebral segment over another And/or 11◦ of angular deformity btn 2 adjacent vertebral segments

Universal emergency policy (collar patients w/ acute trauma)o Neutral Lat taken seated rushed developing immediately evaluated

1st Neutral Lat (translation)o See C5/6 translated anterior w/ facets uncovered (inf facet rides up on sup facet =

instability)o Not a dislocation yet – Soft Tissue Injury

Nuchal interspinous flavum capsule PLL (most posterior to anterior lig’s)

Tear ALL also if anterior translation Locked facet: facet dislocation has not happened yet

2nd Neutral Lat (angulation) – soft tissue injuryo Draw line across the inf Endplate of kyphotic segment and segment below – angle

between can be measured to determine instabilityo Naked facet (uncovered): whole seg above is kyphotico Gapped spinous space Grade 3 flexion injuryo Look at intersection btn normal and straight (shouldn’t have 2 curves in neck)o Signs: find spinous gapping, naked facet, msr angulation!

Hyperflexion Sprain grading: soft tissue Grade 1: clinical diagnosis, trigger tenderness in interspinous space and pt may localize pain

on active/passive ROM (no radiographic presentation)o Tmt as soon as possible for best result (90% of all we will see)o Should you do a trial of care?? Malpractice scare??

Tort Law(all 4 D’s must be proven to win Malpractice) Duty: contract between dr and pt Dereliction: have to do something that is breach of standard of care

Diag Img III Fall 05 12 of 29 Damage: result of the dereliction Direct: damages are directly due to your dereliction

Grade 2: spinous gapping Grade 3: instability (radiographic presentation) Grade 4: U/L or B/L dislocation

ADI: atlanto-dental interval (between dens and transverse lig) Normals: kids <5mm, adults < 3mm ↑ ADI: Posterior tubercle may crush cord (myelopathy: hematoma or ischemia producing cord

injury) Tetra/Quadrapelegia Down’s Syndrome (Trisomy 21): Ligament laxity in upper C/S (~20% affect transverse

ligament)o ROM is normalo Flexiono Extension: ADI back to o Recommendations by AAP on Down’s C/S:

Lat neck films all sports Films in flex/neut/ext If ADI > 4.5mm = NO SPORTS If ADI > 4.5mm & + signs (long-tract signs) = Fusion

Slide showing fusion = did nothing the close the ADI gap!! If Normal = observe no more films If Normal = no restrictions (no test is 100% sensitive)

AAI (atlanto-axial instability) of the ADIOsseous Injuries of C/S:

Classification of C1 Burst Fracture (Jefferson’s): fracture of ant or post archo Stable Jefferson fracture: intact transverse ligo Unstable Jefferson fracture: disrupted transverse ligament (found on APOM) due to lat

motion of lateral masses Spence et al: Total overhang or offset > 7mm of C1 lateral mass and C2 (sum of

2 sides): fracture and instability If < 7mm then just have C1 fracture (trans lig is fine)

Oda et al: Atlantodental interval > 3mm CT shows a 4 part fracture: crack at lat mass connections ant and posterior No distinguishing clinical symptoms from an acute sprain!!

Classification of Hangman’s fractures (VB-pedicle junction fracture of C2)o Type 1 (65%) – undisplaced fracture involving the posterior body or any part of the ring

(C2/3 disc remains intact)o Type 2 (28%) – In addition to the fracture, the body of C2 is displaced anteriorly

(>3mm) or angulated (>15◦). The C2/3 disc is disruptedo Type 3 (7%) – Similar to type 2 but accompanied by U/L or B/L C2/3 facet dislocation

w/ lockingo Radiographic signs: gap btn VB-pedicle junction, spinolaminar line shows posterior

displacement of C2o Distraction Dislocation: Hyperextension injury = occiput hits C2 spinous to cause

hangman’s fracture force continues down to tear all ligaments btn C2/3 to cause dislocation

Dens Fractures:o Type 1: tip of dens (no clinical significance)

Diag Img III Fall 05 13 of 29o Type 2: fractured at base (65%) – dens can potentially posteriorly affect cord or

anteriorly the post arch of C1 can hit cord (unstable!!) Can have same result on cord as trans lig injury

o Type 3: dens and C2 body separated as a unit (can be unstable)o Radiographic presentation: can shoot thru Foramen magnum – dens should be vertical

If tilts 3◦ could be fracture if 5◦ then it is a fracture!! Flexion Teardrop (burst) Fracture (very severe!)

o Typically affecting C5 – not to be confused w/ extension teardrop fragments off C2 or C3 which are usually stable injuries

o Devastating, unstable injury produced by a combination of flexion and axial loading; 49% due to diving and 36% due to MVA’s

o High incidence of neurological damage, w/ the majority (56%) developing quadriplegia o Radiographic Presentation: Teardrop shaped fragment off anterior C5 VB

Wedge Fracture – Acute Fracture of the VB: Posterior VB is normal and the anterior VB is more compressed

o Hard to see in developing spine because all VB angled anteriorly due to under developed growth plates

o Zone of Condensation: bone has been compressed into bone!! appears sclerotic o Step off: fragment of bone knocked loose of the ant VBo STS: soft tissue swelling (not all fractures – especially early on)o Can have osteophytosis due to old, un-diagnosed VB compression fracture (now

become pain generators) HNP Complicating C/S Trauma

o Very little was published about it prior to MRIo High assoc of unstable injuries and HNP (54%); especially w/ facet subluxation or

dislocation. Neurological damage reported w/ closed reduction over an unrecognized…o MRI: subluxation followed by extrusion of disc into the dura

Radiculopathy (NR), myelopathy- affect cord (may see both UMN and LMN signs)

Contusion: compression of cord causing myelopathy (↑ cord signal = looks bright)

25yr female w/ hemiparesis: (which precedes paraplegia)o Diff Dx: Heart stroke, MS, Cord tumoro Actually was a cord contusion (no need to spinal tap!!)o Developed a syrinx: contusion drained down spinal cord leaving

a space in cord Syrinx in C/S attacks the Gleno-humeral jt (↑ dislocation)

Hemorrhage: can be differentiated from contusion on MRI Fat suppression technique: fat appears blk on MR (do when want to see the

water and not the fat signal = more sensitive to detect pathology (water)o Radiographic presentation: C5/6 – see spinous gapping, naked facet, angle > 11◦ (if NR

affected: C5/6 IVF affects C6 NR and dermatome)o CT scan: soft tissue (can’t see trabecular bone) and contrast (makes cord visible and see

bright in subarachnoid space) Dura is not symmetric = extradural compression (indicate HNP or osteophytosis

causing stenosis) Side marking of CT is opp (orientated as if looking at patient from their feet to

their head)

Diag Img III Fall 05 14 of 29 “Spondylolisthesis” of C/S: actually is a dislocation

o Radiographic presentation: see facet dislocation (flex, rotation injury to “jump” facet off the other = Locked facet)

o Normal spondylolisthesis in C/S = congenital due to dysplasic facet or pedicle if don’t see these = is a dislocation!!!

o Bow-tie Sign: of the facets – shows dislocation? Pillar Fracture: extension injury

o Facet surface becomes horizontal (compressed)o Also see IVF stenosis: trauma becomes arthritide (bone hypertrophy ↓ neural foramen)

Impaction fractures: produce zone of condensationo C6/7: ant displacement of sup VB, lucent line on sup End plate, wedge deformityo CT: uncinate process fractured and VB is compressed

Vertebral A Occlusiono More common than previously thought and it can produce neurologic deficito Vulnerable because of t fixation w/in the foramen transversarium (C2-6)o It should be suspected in pts w/ facet dislocations as well as fractures of the foramen

transversariumo Mechanism: stretching and tearing of the intima and media, dissection (distal), mural

thrombus, clot propagation (smaller clots from large clot), and occlusiono Slow progression of this process may allow for an asymptomatic period (hrs to days)o Symptoms: dysphagia, dysarthria (speech affected), dizziness, disorientation, U/L neck

pain and HA, dys-coordinationo Digital Subtraction Angiogram (subtract all but Vert Artery): see ↓ diameter in section

of Vert Ao MR: see signal void (blk) of Vertebral A flanking VB’s (normal)

Absence of the void = no blood flowing (sign of artery occlusion) MRA: subtract all structures but vessels

o Clinical symptoms: multiple cerebellar infarctions (MR shows up wht = ↑ signal) – can occur

o Wallenberg syndrome: when infarction happens in the medulla due to vert artery occlusion

o Spinal Manipulation inducing Vert A Occlusion? 136 cases ever reported (don’t know if had it before?) Risk factors: higher incidence of migraines, HTN, Id risk factors, Id adverse/neurologic deficits, rush to ER Author: Halderman S. - Random complication of ANY neck motion (“sudden

onset of acute and unusual neck and/or head pain may represent a dissection in progress and be the reason a pt seeks manipulative therapy…”

Flexion injuryo Articular processes “perched” on top of each other (flexion injury) - unstable

Spondylolysiso “Scotty dog” – defects occur in “neck”o Occurs m/c < 10 yo!!!o Why occur? – foot of Scotty dog is banging into neck by repetitive hyperextension =

eventually get a stress fractureo May develop excursion – movement of spinal segment = spondylolisthesis (usually

occurs w/in 2 yrs after spondylolysis) Degenerative spondydolisthesis: >40yo, female, arthritic at L4/5

Diag Img III Fall 05 15 of 29 Grading by %: msr endplates perpendicular line to inf VB (line from here to

back of inf VB = %) Sup VB tends to resorb bone due to traction & S1 rounds out

o Spondylolytic spondylolisthesis: not pain generator in adult (pain only while evolving in kids) unless L5 is unstable

If pain = facet syndrome, myofascitis, etco TMT: treat symptoms, can “move bone back”

Break filled in w/ fibrocartilage – some fear HVLA tmt could disrupt this and make it unstable (no supporting research)

Traction technique for radiographs: if unstable = listhesis reduces Displacement anterior when add compression

Unstable if add traction displacement + compression displacement > 3 mm

Rehab protocols need to employedo IN Pediatric population: Acute Spondylolysis

Kid w/ back pain, neg films, neg bone scans, unresponsive to treatment SPECT: see 2 hot spots showing abnormal activity in the pars (bracing is an

option for tmt – have healing bone) If cold still = healing will not occur (no need for bracing)

Compression Fractureo Wedging, zone of condensation, step off fragment of VB (may look like osteophyte!)o ON AP film: don’t see sharp sup VB end plate (suspect but confirm on lateral film)o CT: fracture lines thru VB

Bone window – “double cortex” sign (compressed into VB) Bone scan is HOT

Post traumatic spinal stenosiso CT: see fracture fragment significantly stenosing the canal (also see signs of

compression fracture)o See root signs if at level of cauda equina

Pathologic Fractures: (MR or biopsy required)o Vertebral Plana: > 13% difference in height of post VB (could be from OP)

Lower spine and LE Acute dislocation of Femur Head

o Injury: impaction on knee (MVA – drives femur posterior)o Fractures occur w/ this injury: o CT: posterior column of acetabulum fractured and completely displaced allow femur

head to dislocate easilyo Legg-Calve Perthes ds: Femur head necrosis = fracture line of growth plate – sclerosis

Idiopathic ds (pediatrics) Diff Dx for kids hip pain & limping: transient synovitis (resolves in a few days),

LCP, Infection of hip jt (usually not febile) Hip pain in teen years: Diff Dx adding SCFE (slipped capital femoral epiphysis

– physis is fractured and head slips off)o Osteonecrosis in the adult: male, 40yo, trauma, DM, use of corticosteroids, etc

Intermittent hip pain (activity pain) starts to hurt at rest Biopsy: intra-osseous HTN (pressure too high collapse veins arteries

can’t get blood in bone necrosis Mechanism: Start w/ edema inside bone – collapse vein

Diag Img III Fall 05 16 of 29 Causes: lupus, corticosteroid use, DM, trauma, alcoholism Neck of femur gets fat (remodels) to provide support as the epiphysis degrades

Get new epiphysis 2 yrs later but biomechanics already altered MR: HTN shows signal void at femur head

MOT: myositis ossificans traumaticao See space (cleavage plane) dissecting piece of bone and femur cortexo Complication of mm injury (will have a contusion) – use RICE for local managemento Contusion starts to resolve – palpation shows induration (hardening of tissue) – few

weekso 3rd week – see bone in the soft tissue (keep growing bone for 6 mos)

Can block joint (↓ ROM) = extra-articular ankylosis (outside jt)o Soft tissue Sarcoma: can look identical to MOT

Stress fracture – have malignancy in differential (sarcoma)o Heterotopic (aka: Heterotrophic) bone formation – also paraplegia, coma

Osteochondromao Calcification in bulbus growth outside of hip joint o M/C benign tumor of the skeleton (usually around knee)

Stress fractureo Hamstring injury pt (had 2 stress fractures

2 periosteal rxn along femur (not normal); bone scan showed 2 hotspots w/ linear area on opp side of femur cortex

MR: ring of high signal intensity (periosteal rxn) Concern w/ the marrow – showed no change from other side (rule out

osteosarcoma, osteomyelitis)o 2 forms:

fatigue fracture (abn force on normal bone) insufficiency fracture (normal force on abn bone – i.e; OP bone)

o Cod-fish Vertebrae: bone being taken away faster than it can be re-builto NOT acute pain (low grade ache)

Patella (Knee jt fractures)o Cut mechanism of injury; athletic cleats fix feet to ground, knee bent external forces

to internal of knee vectors on the patella cause lat dislocation of patella Subluxed patella: hematoma pushes patella laterally

Degrees: can break off condylar or patellar cartilage during dislocation Collapse and knee is deformed – knee can be reduced by bring patella back to

position (can cause osteochondral fracture) cause further damage to knee jt Iceberge effect: see only calcified fragment when attached to larger piece

of cartilageo Lat Plateau fracture (due to lat blow) – cartilage disrupting the joint (complicate

fracture = ↑ risk of OA)o Med column fractured – displace fragment inferior

MR: see bone bruise – see blk moddled appearance of the bone (low signal surrounded by high signal fat)

BME: bone marrow edema (occurs w/ ACL tears, etc) Get pain but goes away – complication can be osteonecrosis!!! (if pain

comes back) Not same as sub-periosteal hematoma

o Meniscal injury on MR: degenerative tear shows bright

Diag Img III Fall 05 17 of 29 Acute tears: wht line from articular surface to articular surface (cartilage causes

clicking, popping, pain) Must be repaired (grade 3 tear) High signal = edema w/in tear of the meniscus (normal should all be blk)

Elbow: constitute 6% of all fracturesAdult ChildRadial head (50%): Supracondylar (60%)

o FOOSH: ”fall on outstretched hand” (m/c: 3 fractures: radial head, humeral greater tuberosity, scaphoid fracture)

o Humeral condyle compacts the radial head (impaction – see some sclerosing and some angulation of the radial head)

o Little league elbow: Group of pathologic changes in young throwers (bone is still growing)

Mechanism: pull on medial side and compaction of lateral side Jt will lengthen abnormally, epiphysis closes quicker (↓ blood flow)

OA Also seen to arise from the tennis serve and football pass (baseball) Medial epicondyle fragmentation and avulsion (epiphysis), growth alteration of

the capitellum, osteochondritis of the radial head, hypertrophy of the ulna and olecranon apophysis

C (capitellum)R(radial)M(med epicon)T(trochlea)O(olecranon)L(lat epicon) order of epiphyseal development (2-12 yo)

“Come rub my tree of love” (order of maturation of the growth plates) Salter Harris fracture (grade 1: crack thru physis)

o Pediatrics <16 yo: tensile strength of lig is greater than tensile strength of cartilage (physeal injury more common than lig injury)

o ORIF: open reduction (pin, clip, nail, suture) internal fixationo Elbow dislocation:

Football, wrestling and gymnastics may produce this injury PL displacement is m/c Injury of the jt capsule, brachialis mm, ulnar collateral ligament, medial

epicondyle is likely; less likely brachial a, median or ulnar nerve injury Sign finding: nerve, artery damage (more severe w/ dislocation than fracture)

4 stereotypical fractures/dislocations:Galeazzi Monteggia Colle’s Smith

Dislocation X (distal ulna) X (prox radius)Fractures X (distal radius) X (prox ulna) X (distal radius) X (distal radius)Location Wrist Elbow Wrist WristMechanism (FOOSH)

Shortens radial bone and ulna compacts & dislocates into the wrist

Shorten ulna, vector of energy transmitted to radial head (tear annular lig) dislocation

~ 60% will have fracture of ulnar styloid (FOOSH)* Posterior angulation of the distal fragment

*Anterior angulation of distal fragment- Wrist left in neutral/flexion (CNS conduction too slow) when fall (>75 yo)

Diag Img III Fall 05 18 of 29Differentiate btn Collies & Smith: Find thumb on palmar side to determine direction of displacement!!*Collies is the 1st osteoporotic fx (~50 yo) 2nd is the codfish vertebrae 3rd is femoral fx (>80 yo – 1:5 females and 33% will die)

Salter-Harris Classification of FracturesType 1 Fracture of physeal plate Space btn the epiphysis and metaphysisType 2 Fracture of physeal plate and metaphysis (m/c) Metaphysis (end of bone)Type 3 Fracture of the physeal plate and epiphysis

including the articular surfaceEpiphysis (separated portion)

Type 4 1-3: fracture of physeal plate, metaphysis, epiphysis

Type 5 Physeal compression deformity

Dorsal displacement of radial epiphysis (looks like the radius has gone to palmar side) – type 1o Not a wrist dislocation because radial epiphysis and lunate articulation is unchangedo Also see Carpal coalition (lunatotriquetral coalition): like a congenital blocked

vertebrae Wrist articulations (collinear relationship – lat view): Radius (ulna w/in borders) lunate

capitate 3rd metacarpalo See luscent line (fat plane along pronator quadratus – important line in determining

fracture – i.e; should be straight on dorsal/radial side . Wheeless’ Textbook of Orthopaedics (online): good for review (also use in practice)

o www.wheelessonline.com o Caralinskis website?

Torus fracture: (lip of top of architectural pillar = torus)o m/c fracture of the wrist in pts aged 6-10 (FOOSH mechanism) – good prognosiso Typically located 2-4 cm from the distal growth plateo Classically an impaction injury – ALWAYS PROXIMAL TO A JOINTo Xray appearance: see a “lip/bump” interrupting the cortical margin of bone (seen best

on lat view) Wrist evaluation:

o Plain film assessmento The 3 arcs of carpal alignment:

1st: prox row on prox cortex should be continuous 2nd: on distal aspect of prox row 3rd: cortex around capitate and hamate Dorsal Perilunate dislocation: lunate not articulating w/ capitate anymore

(capitate is the one dislocated) Window of repair 10days

Diag Img III Fall 05 19 of 29 See breaks in all of the arc lines

o Aka: Gilulas’ lineso Joint spacingo Articular alignmento Soft tissue assessmento Wrist series: 4 view recommended

Fine grain screens reduce the rate of false neg’s Navicular fat stripe sign (+) in 90% Clinically:…..

Scaphoid fx:o M/c carpal bone to fxo Age of occurrence betn 15-40 yrso Rare in childreno m/c for occult fxo Mech: complex injury patterns

Same amt of hyper extension and radial flexion FOOSH 70% involved WAIST? Bone scans (+) w/in hrs of injury (6-16%) When scaphoid fr doesn’t heal – pin is needed (Herberts pin) Avascular necrosis can occur – retrograde susception to nonunion

Scaphoid fracture complicationso Prox waist fracture, prox poll fx may demonstrate avascular necrosis (15% of scaphoid

fractures) Vascular pattern: SLAC wrist

Scaphoid has 2 pieces (nonunion) Cortical margin is interrupted (erosion & cyst in lunate) No radial compartment – OA Mechanism of SLAC wrist: scaphoid fx nonunion every time

clinch fist = capitate migrates proximally destroys fx fragment and the lunate! (eventually wrist will spontaneously fuse)

o Nonunion (30% of wrist fx)o Carpal instabilityo Radiocarpal degen arthritis

Colle’s Fx xray appearance: see luscency where screws were put in, marked osteopenia in prox radius/ulna and all carpals (starting OA)

o Allodynia: pt feels pain on slight touch (also seen in fibromyalgia)o Hyperalgesia: pain stim becomes magnified paino Both above are nerve injuryo CRPS: complex regional pain syndrome (aka RSDS, Sudeck’s atrophy)

S/S: allodynia, hyperalgesia, and osteopenia (↑ sympatheticotonia) Can develop in opp limb or whole body mediated thru spinal reflexes See pain out of proportion to injury = think CRPS Treatable early on: exercise and mobilization (restore sympathetic tone)

o Can’t do in acute phase! –o Drugs and sx option (not always good results)

Type 1: no nerve lesion can be identified (whole arm hurts) Type 2: identifiable nerve lesion

Diag Img III Fall 05 20 of 29 Kienboch’s Ds

o Avascular necrosis of the carpallunateo 1st described by kienboch in 1910o Produces great pain and loss of functiono Males – females = 9:1o 20-40 yoo Previous hx of acute trauma or repetitive traumao Plain films neg – 12 moso Pos during re-vascularizatrion stage (6mos – 4 yrs) the repair/.remodeling stage (1-2

yrs) and deformity stageo Bone scan will be positive earlyo MR is the most sensitive

Appearance: bone marrow edema (low signal on T1 image) Triangular fibrocartilage tear: ulnar side of wrist – meniscus attached to ulna and radius by

lig’so Frequently seen in athletes who experience repetitive wrist loading particularly

gymnast, pole vaulters, martial arts strikes and blockso Presentation: wrist pain and clickingo MR dx: appears ↑ signal intensity (should be black)

Thumb injuries:o Gamekeepers Thumb: avulsion of collateral ligs of thumb (stress views and MR)o

.MT: 50Q’s; describe cases – findings, dx, etcSyllabus: topics of normal anatomy & differentials?, axial/apendicular deg ds; most exam is trauma based (ch 4) – look at image captions, chapter summaries

Neuroradiology Section: 2 specialties Skull, brain, cord Head & Neck : skull, sinus, orbits, neck Cord: most central neurologic deficits are peripheral – radiculopathy or neuropathy (CNS, PNS,

ANS)o CNS branch (myelopathy NOT radiculopathy – is m/c) – spondylotic myelopathy

(compressive)o Tumor and MS (looks like spondylosis before imaging) o S/S: UMN findings, o DDx depends on location (presentation of cord disorders)

Extradural: outside both cord and dura Imaging:

o Thecal sac (dura) deformed/compressed from outside-ino Extra “mass” seen in canalo CT myelogram or T2 MR thecal effacement (compress) or

min CSF visualizationo DDX: degenerative ds (95%), trauma, iatrogenic, hematoma

(canticoagulation), abscess, tumor 70% malignancy become extradural problem >50 = spinal stenosis

Diag Img III Fall 05 21 of 29 <50 = HNP

o Reorganization (neuroplasticity) Intradural/extramedullary: outside cord but inside dura

Lesion involved dura or subdural space DDx: meningitis, meningioma Schwannoma (neurofibroma), METs (via

CSF) Intramedullary: intradural w/in substance of the cord

Imaging: expansion of cord is key finding (in neoplastic lesions) DDx: cells (tumor): ependymoma – adult or astrocytoma/glial cell -

kids, METso Inflammation, blood, syringomyeliao Multiple Sclerosis: young, female, periorbital paresthesia, LE

paresthesia B/L MS: characterized by Neurologic lesions that vary in time

and space 80% are relapsing/remitting (R/R)

Intramedullary Tumors:o Most are malignanto Most are of glial origin (ependymoma or astrocytoma)o Adults: ependymoma is m/c, astrocytoma is 2nd (reversed in kids)o Clinical symptoms are nonspecific: local pain, sensory and/or

motor losso Eval of Intramedullary tumors:

Cord expansion suggests neoplasm (large cords w/ abn signal)

Most cord tumors show contrast enhancement (T1 contrast enhanced exam) – changes the magnetization of the tissue (pathology becomes bright)

Cysts are commonly associated Non-tumoral (polar) cyst – syrinx (cord damage

w/ fluid collection inside) Tumoral cyst

o Ependymoma: Ependymal cells line the ventricles and central canal (m/c

central in location w/ symmetric cord expansion) Slow growing, compresses rather than infiltrates adjacent

cord, well-circumscribed Cervical location only (45%), cervical w/ extension to T/S

(23%) Radiography canal widening, vertebral body scalloping,

pedicle erosion CT: cord expansion, contrast enhancement MRI: ↓ T1/↑ T2 avg. 3.5 vertebral segments involved,

“cap sign”, cysts common (usually polar), contrast enhancement, sharp margins

o Astrocytoma T/S location is m/c More infiltrating (less well circumscribed) Eccentric location w/ expansion

Diag Img III Fall 05 22 of 29 Tumoral cyst m/c Prognosis worse because its not easily removable Radiography, CT: widened interpedicular distance, bone

erosion (less common than w/ ependymoma) MR: poorly defined, ↓ T1/↑ T2, avg 7 segments involved,

cysts( both types), contrast enhancing, eccentric expansion (grows on outer margins of cord)

Imaging options

o Plain film – can’t see neural structures on xrayo Myelograghy

L5 80% herniation to see o CT myelographyo CT w/ IV contrast (gadolinium – use in post-op spinal pain) – scar vs herniation

Scar doesn’t take up contrast because not vascularo MRo MR w/ IV contrast

Normal anatomy of skull 4 views in series

o Lateral (right and left)o PA – Caldwello AP – Towne: pt supine, beam comes down at 30◦ and exits at foramen magnum

Visualize foramen and posterior fossa (lobes of cerebellum)o Sinus series:

Waters view (“nose/chin view”) – maxillary sinus (pt pace on cassette) PA – Caldwell Lateral – sphenoids and down to maxillary anteriorly

Landmarks:o Head of caudate nucleus (lateral ventricle)o Paired thalamic nuclei above the “smiling face”o Midline shift: mass can push brain across midline (↑ intracranial pressure – ICP)

Easiest thing to push (subthalseal herniation) Most dangerous – herniation down out of foramen magnum (RAS system)

o Physiological calcifications: (normal) coraid plexus, basal ganglia, tentorium, pineal gland,

Pathological calcification: aneurysm, atherosclerosis, infections (TB, syphilis, neonate HIV), tumors

o Supraventricular cut: Centrum cisterna ovale: wht matter of corona radiate (demyelinating ds

preference – MS plaquing) Dawson’s fingers: perpendicular to the ventricle (MS plaques)

o Top of calvaria: Gyra: folds of the brain

Alzheimers: atrophy of the gyra and sulci deepeno Neurofibrilary tangles: 6 layers of neurons in brain, usually

linear, become entangledo Amyloid protein plaques inside/beside Tangles

Diag Img III Fall 05 23 of 29o Can see all of these signs in pts w/out Alzheimers!!!

Sulci: Valleys between gyrus See falx cerebri Skull enlarges and brain shrinks w/ age – more opportunity to subdural

hematomas (brain hit skull)

SKULL PATHOLOGY (Dr. Hahn) Osteolytic Lesions

o Metastatic lesions: looks like dark holes Breast cancer is common

o Multiple Myeloma: punched out lesions (multiple)o Asymptomatic lesion: very large dark hole = Pagets

PA Chest Films Indications for films: coughs, unexplained symptoms, hemaptosis, cardiac symptoms (SOB) Central shadow: mediastinal cavity (heart, esophagus, a/v, lymph, phrenic n, other neural

structures)o Coronary artery ds eliminated = diagnosis of esophageal ds (mimicry) – also T/S pain

Included in the rib series (expiratory for ribs)o Pneumothorax w/ or w/out rib fx (neg air density – opacity of lung by air)

Chest film search pattern: 5 phaseso Soft tissue (outside the thorax – neck, under diaphragm, on thorax)o Osseous structures (vertebral column, shoulder complex – scapulae, clavicle, humerus;

ribs)o Central shadow (mediastinal cavity) – trachea, mediastinum, o Evaluation of Hila (hilum) – region where pulmonary arterioles and lymph nodes reside

Bronchogenic carcinoma (m/c in US death) – diagnosis of mass here unless proven otherwise

o Lung & pleura: nodules, thickening, calcification, Lung eval w/ + or – densities

Positive lung densities (4) vs Neg lung densityPneumonia, (consolidation): alveolar spaces filled w/ something (usually infective process)

localized or diffuse (could by malignancy causing and being masked by pneumonia) – common misdiagnosis

COPD: emphysema, chronic bronchitis, chronic asthma

Destruction of lung parenchyma Hyper inflation: end expiratory volume

increase (residual) thorax inflates

Solitary pulmonary nodule (no calcification) – (< 3cm = coin lesion) differential includes bronchogenic carcinoma, mets to lung, granuloma (benign – infective process or histoplasmosis – eventually will calcify)

Pneumothorax: lung is not abnormal, but air in the pleural space causes lucency * Visceropleural line (wht line??)

Calcified granuloma – solitary pulm nodule that becomes calcified*not clinically significant

Pulmonary cavity: either bronchogenic carcinoma or infection m/c

Squamous cell carcinoma: center of lesion doesn’t have good blood supply necrotic cavity forms in center of tumor (attempts to

Diag Img III Fall 05 24 of 29block vasculature to tumor for therapy)

Pulmonary mass >3 cm (diff dx: 1◦ malignancy = bronchogenic carcinoma, 2◦ mets, abscess)Atelectasis: insufficient inflation

2nd cause: bronchogenic carcinoma (displaced structures – magnet like pull w/ alveolar collapse)

1◦ cause: fissures

Technical issues: o HIGH kVP (> 120 KV)o Right Hemidiaphragm at the 10th R rib (inspiratory examination – anything less =

expiratory examination)o Rotation: never get pts perfectly PA – can appear clavicle dislocation

Cause prominent hilum on side of rotation (may simulate denser hilum as w/ bronchogenic carcinoma – radon gas, 2nd hand smoke)

Bronchogenic carcinoma: Semental HI??o Tumor growing – air gets thru (expand) on inspiration but not on

expiration (contract) Collapse of alveoli magnet like pull on all structures

i.e; heart shadow on one side of T/S, tracheal deviation, etc

Easy sign: med borders of the clavicles equal distance from spinous process (one will be typically wider – most common w/ scoliosis

If radiograph in AP: heart will be enlarged by 13% (false diagnosis of cardiomegaly) – even larger w/ expiration

Anatomy:o C/S paraspinal soft tissues: look for calcification (common) – either vascular

(atherosclerosis – carotid bulb) or adenopathy ( Bruit…..95%,…..

o Breast density: extends beyond the thoracic wall (not in thorax but ON the thorax – differentiate masses)

o Diaphragm Right heimidiaphragm is higher = normal finding

Pneumoperitoneum – air outside the GI tract (rupture)o Ulcer or tumor ER situation

Anterior Costophrenic angle (sharp, acute angle on both sides) Blunting of angle = sign of pleural effusion Meniscus sign: fluid drawn up (pleural effusion) of sides (like test tube

meniscus) Causes of pleual effusion: CHF, Pneumonia, malignant tumors

o Posterior costophrenic angle: seen on lateral view More sensitive to pleural effusion (blunting) Mesothelioma & bronchogenic carcinoma (asbestos + smoking = ↑ 30% risk of

BGC)o Soft tissue below diaphragm = most liver

Fundus of stomach Colon (gas)

Diag Img III Fall 05 25 of 29 Liver (homogenous) Spleen – next to colonic flexure (if can see = splenomegaly) Multiple dilated loops of small bowel w/ air/fluid levels = ER situation

(hallmark of small bowel obstruction – progressive pain, perforation complication peritonitis (contents of GI tract – chemically corrosive and bacteria)

Caused by adhesions – bands of fibrous soft tissue (edema becomes adhesive fibrosis) – post sx

Hernia strangulation – incarceration (not able to put bowel back = irreducible)

Colon carcinoma – tumor strangulates loop of bowel (closes the lumen) Skeletal abnormalities:

o Congential (short clavicle)o Trauma: rib, clavicle, VB fx, arthrotides of jts (RA, OA), o Hyperparythroid – rib notching

Central shadow:o Tracheal deviation: presumption of tumor, thyroid ds, parathyroid masses,

lymphadenopathy) push tracheao Cardiac sillouette: level of aortic arch – width of mediastinum should be same as

vertebral column Measure heart at widest point to the midline and sum the interval (cardiac

component on numerator) Denominator is Thoracic component (rib to rib????) CT ratio should be less than 0.55 in adult (if > cardiomegaly)

o Principle causes: HTN (dilation and hypertrophy w/ L-vent heart failure) – occurs in 50 million Americans

o Valve ds – irregular borders – insufficient or irregular closing (stenosis)

o Right sided heart failure (chronic lung ds) – cor pulmonale (lung ds causing heart ds) affect L side later

Pulmonary arteriole HTN: heart works harder to pump blood to lung (causes cor pulmonale)

o Hilum: normally see main pulm artery w/ branches (higher on L side) – only opacities normally seen in the chest film (wht lines)

Normal structure on right = horizontal fissue (opaque) – separate middle from upper lobe (may be seen)

Numerous lymphnodes (can’t see unless calcified = adenoma, infection) 2 structures in the hilum (vessels and nodes) HTN (primary and secondary)

Primary: rare, middle age females, pulmonary arteriole vessel thickens until lumen disappears (↑ pressure – rapid heart ds fatal w/in 2 yrs)

o Idiopathic nature Secondary

Shunt vessels – vessels become prominent in hilum Nodes: tumor, metastisis, benign cause is sarcoidosis (immunologic disorder

afflicting African American females – lymphadenopathy on both sides of hilum 1,2,3 sign (paratracheal nodes, and B/L hilum nodes) Skin test (Kvein test) – current test is angiotension converting enzyme

elevation

Diag Img III Fall 05 26 of 29 Vessels vs nodes: biopsy lymph nodes (differentiate CT scan)

Chest Radiology (Dr. Hahn) Normal pectoral muscle line (lateral thoracic wall) – B/L sign

o Mistaken for Pneumothorax: looks like a thin line, vertical along lateral chest wall Consolidation: malignancy will also see destruction of surrounding structures

o See “mass” in Upper R lungo Tomograph shows notch in the rib under the mass = neoplasia

Calcification of the diaphragm Calcification of 1st rib costocartilage (normal) Elevated R side diaphragm = scoliosis causes high diaphragm on side of convexity (also will

see vertebral column deviation) Curvilinear calcification at the aortic arch = (“thumbnail sign) Calcification in the lung apices- calcification of the pleura due to infection (histoplasmosis, TB,

etc) Cyst in the lung apex: Well defined border, oval shaped, luscency = normal

o Lung seen between the 1st rib and the subclavian vessels = lung apices

Dr. Kettner back Final 50Q; m/c some multiples (differential dx); cases Degenerative ds: OA, neuroarthropathy, synovial osteochondromatosis (aka?) *Trauma: axial, appendicular, mechanism of injury, complications of trauma (myosistis

ossificans) Epinem list (i.e; Jones’ fx, etc) Head/neck neuroradiology: thyroid mass, tumor, aneurysm, etc (major conceptual

understanding) *Chest: 5 steps of search pattern, causes for tracheal deviation, etiology for enlarged heart on

specific side (cor pulmonale); DDX for nodule, mass, etc (clinical context)

Pitfalls in chest radiology Bumps of heart: aortic arch, pulmonary artery, LV (sup to inf on R side)

o RV bump on L sideo Extra bump = is it lung or mediastinum?

Mediastinal mass – deflects pleura laterally (should only be as big as vertebral column at level of the aorta)

5 T’s: Thyroid descending from neck, embryologically thyroid developed lower Thymus did not atrophy as much as normal (thymoma – high assoc w/

Myasthinia Gravis – neuromotor junction) Teratoma: pre-malignant tumor (5% progress to cancer) – clump of all

times of tissue (ectoderm, mesoderm, etc) Lymphoma Ascending aneurysm

Lung abnormalities: + or – densitieso Summation artifacts: add up densities of surrounding structures around part of lung

(rib, cartilage, artery) – appears as a cavity (lucency)o Cavitary structure: has opaque density inside w/ an air fluid interface (AFI) – see in the

abdomen (small bowel obstruction)

Diag Img III Fall 05 27 of 29 Not summation! – m/c reason is lung destruction following infection, 2nd cause

is tumor (*almost always malignant, m/c squamous cell carcinoma) Neovascularity – new blood supply to tumor but can’t support the center

of the tumor (lucent) Smoking leading cause of lung cancer 2nd is passive 3rd is radon

o Hiatal hernia: see air bubble in fundus of stomach (have reflux) seen w/in the heart on film (actually behind the heart)

o Tortuosity (serpentine): change in the ascending aorta (enlargement of the mediastinum) – HTN shows wider aorta (abnormal, elevated pressure)

Radius of curvature should come up to the aortic arch (uniform) If goes above = something else unless aneurysm Do CT if unsure

o Area of scar (subsegmental atelectasis) – results from immobilization of the lung (avoid breathing due to pain post-sx) cough to avoid scar or pneumonia

Diff Dx for Solitary pulmonary nodules: infection & neoplasia (pos density)o Anything seen in lung that doesn’t belong = same default victane categories

Medial Mediastinal masses: bronchogenic and lymphoma Posterior mediastinal masses: neurogenic (neurofibroma, meningioma, gangioneuroma)

o Diff includes: thoracic aortic aneurysm; paraspinal masses (hematoma, myeloma) Vessels off Aortic arch

o Brachiocephalic R carotid, R subclaviano L carotido Left subclaviano Anomalies: L subclavian may come off the brachiocephalic

R sided aortic arch (usually on L – tetrology of flow-cyanotic heart ds) May get double arch (traps the trachea) stridor and dyspahagia

LA more posterior than the LV Coronary angiogram – gold standard for eval of CAD 700,000 MI per year (death every 20

sec)o Pressure on chest, dyspnea, diaphoretic (sweating); preceeding by “sense of impending

doom” ~ 12 hrs earlier o Risk factors: male, DM, age, HTN, ↑ cholesterol

1/3 of MI do not have any classic risk factorso Angina: mm do not have adequate profusiono 0.6% pts who undergo coronary angiography die due to procedure (CT and MR may

take its place in the future)o LAD (L anterior descending) – supplies the LV (“widow maker”) – m/c in MI

70% reduction of vessel before angina symptomso Done prior to angioplasty (balloon – compress plaque; lasers)

Atherosclerosis is a systemic disorder!!! Dr. Ornish: said atherosclerosis is reversible based on lifestyle changes

Cardiomegaly: heart size > .55 (PA chest on fill inspiration – cross diaphragm at 10th rib)o Causes: CAD, HTN, Dxo Msr: midline to each side heart shadow add the #’s should be < half the thoracic

msr??:??o Work up: ecocardiography, US, stress EKG o LV contracts – 2/3 blood in chamber pushed out (declines w/ age)o Ischemia/hypoxia w/ ↓ Cardiac output (decline 1%/yr beginning at age 19)

Diag Img III Fall 05 28 of 29 Respiration: affect on PA chest film view (Insp vs Exp)

o Heart size ↑ by as much as 20% on expiration and diaphragm goes upo Chronic respiratory insufficiency – obesity ventilation reduces because diaphragm

can’t go down Cor pulmonale

o Capillary vascularity of lung is atrophied due to emphysema, etc (R atrial and R ventral atrophy)

o Will eventually cause L sided heart failure (hypertrophy) Atrial myxoma: M/C tumor of the heart

o Tumor flaps between the L atrium and L ventricle R side heart will enlarge

Fibrotic lung diseaseo Pronounced pulmonary arteries (pulmonary artery HTN)o In young individual (Cystic Fibrosis)o Capillary atrophy resulting in fibrosiso Retrosternal air space ↑ as w/ emphysema & diaphragm arc flattening

HTN: affect on the hearto Rounding below the diaphragm of the LVo Prominence of the aortic arch (↑ pressure)o Common cause of heart diseaseo Hypertrophy then dilation of LV (↓ ability to contract as it dilates/stretches)

CHF (congestive heart failure)o Cardiothoracic ratio > 55%o Jugular venous distention, pulmonary edema (alveolar spaces filled w/ exudates –

leakage of the vessels) Rales are a sign of thiso Pre-cordial Heaving: heart is rolling and contacts chest wallo Peripheral edemao Nocturnal Paroxysmal dyspnea (violent coughing and SOB especially during sleeping)

– prop up on pillowso ↓ Cardiac output – MI due to ischemia

Pectus Excavatum – sternum is concave pushes the heart to the left (don’t see R heart shadow

o Severe and no thoracic curvature = Straight back syndrome (heart trapped btn the sternum and vertebral column

Cause heart murmurs Ventricular Aneurysm:

o Acute MI: damage mm results in expansion of the LVo Rupture is fatalo Calcification w/in structure (LV) – due to ischemia

Calcification of mitral valve (also aortic)o Insufficiency or stenosiso Cause of calcification w/in the hearto LV out on thoracic wall!!o Tortuous aorta (↑ in size) – compensation for the calcification

Atelectasis (indirect sign)o Mediastinal or tracheal deviationo Diaphragm elevation

Diag Img III Fall 05 29 of 29o Hilar elevatedo Depressed intercostals narrowingo consolidation

Direct sign of atelectasiso Right and left long fissures may be displacedo Fissures not where they should be

Silhouette signo In the lung