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48M Feelings of ankle instability. MOCK ORAL BOARDS 2005 GENERAL RADIOLOGY Don Fleischli, M.D., M.B.A. Associate Clinical Professor, U.C.S.D. School of Medicine Assistant Professor of Radiology & Radiological Sciences, U.S.U.H.S. GENERAL SUGGESTIONS. What is the exam? What are the findings?
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MOCK ORAL BOARDS 2005GENERAL RADIOLOGYDon Fleischli, M.D., M.B.A.Associate Clinical Professor, U.C.S.D. School of MedicineAssistant Professor of Radiology & Radiological Sciences, U.S.U.H.S.
GENERAL SUGGESTIONS • What is the exam? What are the findings? • You have seen one like this in your review! • Obvious findings - long DDX or detailed discussion? • Aunt Minnie? It looks like…but could be…. • Corner of film type trick that looks normal? • Have a script in mind so when your mind goes blank… • Usually you get no history until you ask • Don’t ask until you have run through your script • An example of a category script…don’t step INIT • Infection…bacterial, viral, fungus, immune sys… • Neoplasm…benign, malignant, pseudotumor… • Inflammation…arthritis, collagen vasc, drugs… • Trauma/Other…extrinsic, mechanical, rupt, vasc…
GENERAL SUGGESTIONS • Pick a category and pursue it until exhausted or the examiner directs you away from it • Don’t jump to another category quickly, it may take you down the wrong path…“this could be tumor…” • When exhausted go to other categories, say “this looks inflammatory but could be trauma or infection or neoplasitic…”; “I would recommend…” • Couch your discussion in terms of assumed clinical findings…“if this pt is immune compromised I would consider…if not I would consider” • Start by stating the obvious category and diagnosis • Don’t mumble/shout/run on/interrupt/joke/ask for Dx • If examiners says “is there anything else you would consider”…go back to INIT then ask for more history…or mercy
ACTUAL SCORE SHEET FROM ABR • Case # • -- - + ++ +++ • Observation • Synthesis/Imp • Management • 68 69 70 71 72 • Score
CASE #1 - DISCUSSION • Findings • Multiple erosions/uniform joint space narrowing • Ulnar styloid erosions; pisoform/triquetrum early • Subluxations; mention SLE best seen in Norgaard view • Osteoporosis; juxta-articular>>diffuse • Little fusiform soft tissue swelling; early sign • Bilateral symmetrical • No swan neck and boutonniere deformities distal phalanges • Differential Diagnosis Infection • Differential Diagnosis Neoplasm
CASE #1 - DISCUSSION • Differential Diagnosis Inflammation • Rheumatoid Arthritis • HLA-B27 Arthropathies-mineralization-bone formation • Erosive Osteoarthritis-1st CMC and DIPs, central seagulls • Gout-no overhanging edges with sclerosis • Differential Diagnosis Trauma/Other • This does not look like primary or secondary OA • Diagnosis: Rheumatoid Arthritis (advanced) • Short Read: • Discuss types of erosions in other arthritis • Bare area of joint within capsule not covered by cartilage • Lack of bone formation seen in Psoriatic, not in DIPs • Ankylosis of carpals but not distal to them
CASE #4 - DISCUSSION • Findings • Calcified stone in distal left ureter • Scattered calcifications in soft tissues • Typical ovoid elongated calcifications in muscles • Differential Diagnosis Infection/Inflammation • Cysticercosis with calcified left ureteral calculus • Trichinosis cysts are tiny, round, punctate (mammo) • Guinea worm dz, Echinococcosis, Sarcosporidosis, Loiasis also have soft tissue calcification • Dermatomyositis and other collagen vascular dz
CASE #4 - DISCUSSION • Differential Diagnosis Neoplasm • Differential Diagnosis Trauma/Other • Myositis ossificans • Vascular calcifications • Diagnosis: Cysticercosis & ureteral calculus • Short Read: • Taenia solium (helminth)=pork tape worm (cestode) • Humans are the only definitive host of adult worm in the intestine; hog and human are intermediate hosts • Larval form in muscles and viscera >>die>>Ca++
CASE #5 - DISCUSSION • Findings • Complex vertical fx probably stable • Interpedicular distance wider than above or below • Posterior superior corner fragment>>spinal canal • Posterior ligaments and bones intact • L-2; typically 67% T-12, L-1, L-2 junction stable to mobile • Differential Diagnosis Infection • Differential Diagnosis Neoplasm • Differential Diagnosis Inflammation
CASE #5 - DISCUSSION • Differential Diagnosis Trauma/Other • Simple wedge fracture in osteoporosis (insuff) or normal bone • Burst fracture is vertical (ant/mid column); stable or unstable • Chance fracture (lapbelt only) is horizontal; no anterior column compression like burst fx; bone/ST; stable or unstable • Flexion distraction injury; combination of both; ant column + • Diagnosis: Burst fracture • Short Read: • Three columns (Denis); CT for middle and posterior columns • Simple wedge anterior column only…mechanism of injury • Anterior/middle columns in 85%; 25% middle column miss • Posterior column and/or ligaments involved on CT=unstable • CT the night of injury then MR the next day for ligaments • Unstable (two columns + ligs)>>further neurological injury
CASE #6 - DISCUSSION • Findings • Chondrocalcinosis both hips • Protrusio acetabuli with uniform joint space narrowing • Differential Diagnosis Infection • Differential Diagnosis Neoplasm • Differential Diagnosis Inflammation • CPPD crystal deposition disease • Gout (if chondrocalcinosis it is not CA++ urate but CPPD) • Pseudogout
CASE #6 - DISCUSSION • Differential Diagnosis Trauma/Other • Chronic trauma>>DJD with chondrocalcinosis • Diagnosis: CPPD “pseudo-rheumatoid arthritis” • Short Read: • Calcium PyroPhosphate Dihydrate (CPPD) deposition dz • Chondrocalcinosis with secondary DJD • May be aggressive and look like neuropathic joint • May look like RA “pseudo-rheumatoid” but no erosions vs true RA with erosions and CPPD; unusual secondary OA • Diagnosis by CPPD crystal identification • Knees, hands, hips, shoulder, elbow; need two areas for DX • Arthropathy of CPPD resembles secondary OA usually
CASE #15 - DISCUSSION • Findings • Erosions with overhanging edge, sclerotic cortical rims • Normal mineralization, joint spaces preserved • Look for faint soft tissue calcification=tophus • Differential Diagnosis Infection • Differential Diagnosis Neoplasm • Differential Diagnosis Inflammation • Gout (if chondrocalcinosis they also have CPPD) • Rheumatoid arthritis • Osteoarthritis • HLA-B27 arthropathies
CASE #15 - DISCUSSION • Differential Diagnosis Trauma/Other • Diagnosis: Gout • Short Read: • M:F=20:1, elevated uric acid, monosodium urate monohydrate deposits (tophi) which may calcify and be seen on films • Many diseases cause elevated uric acid (myeloproliferative) • Uncommon before age 20 yrs, oldest recognized arthropathy • Must have untreated disease for years to see changes on films • Feet (1st MTP), hands, elbow, wrist, knee, shoulder, hip, SI Jnt • Asymmetrical polyarticular distribution, indolent, remodeling • Secondary gout with increase production or diminished excrete of uric acid usually have no radiographic changes
CASE #16 - DISCUSSION • Findings • Bubbly lesion with fracture no periostitis; chondroid matrix • Differential Diagnosis Infection • Osteomyelitis (bacterial or fungus) • Differential Diagnosis Neoplasm • Enchondroma • FOGMACHINES or FEGNOMASHIC for benign cystic lesion • Chondroid matrix=popcorn, speckle, swirled, punctate Ca++ • Osteoid matrix=denser, cloud-like, mashed potatoes Ca++ • Zone of transition=narrow benign, wide malignant; slow growth time to retreat in orderly manner; rapid permeative • Periostitis may be benign (benign lesion) or aggressive (either)
CASE #16 - DISCUSSION • Differential Diagnosis Inflammation • Differential Diagnosis Trauma/Other • Healing displaced fracture • Diagnosis: Enchondroma with Fracture • Short Read: • Most common lesion of phalanges, diaphyseal, lytic, expansile, thin sclerotic rim, may not have chondroid matrix in hand • Ollier’s dz multiple unilateral, Maffucci syndrome multiple A/W hemangiomata more likely to degenerate into malignancy • Films underestimate true size; MR/CT better • Geographic lesions=those with distinct margin sclerotic or not
CASE #17 - DISCUSSION • Findings • Cocktail hot dogs or sausages (soft tissue swelling beyond joint) • Normal mineralization • Bone proliferation=hypertrophic bone at ligament attachments • Differential Diagnosis Infection • Osteomyelitis • Differential Diagnosis Neoplasm • Differential Diagnosis Inflammation • Psoriatic arthritis • Rheumatoid arthritis, Reiter’s dz, HLA-B27 arthropathies • Osteoarthritis • Gout, amyloid, sarcoid
CASE #17 - DISCUSSION • Differential Diagnosis Trauma/Other • Fracture or soft tissue hemorrhage and periostitis • Exostosis • Diagnosis: Psoriatic Arthritis • Short Read: • Erosions and bone formation (DDX RA) • Mouse ear hypertrophy next to marginal erosion • Pencil in cup central erosions (late) may widen joint • Soft tissue swelling beyond joints, normal mineral • 1)DIP/PIP joints involved, 2)rays 1-3 all joints, 3)like RA but DIP, bone prolif, normal mineralization • Feet more than hands; bilateral asymmetrical; Achilles and plantar aponeurosis bone proliferation
CASE #22 - DISCUSSION • Findings • Periosteal new bone 3rd metacarpal • Sclerosis (not quite bubbly) • Bubbly/lytic/sclerotic process distal left clavicle • Positive three phase bone scan in above and spine • Chest shown no coin lesion or cavity • Differential Diagnosis Infection • Cocci osteomyelitis • TB or fungus, pseudomonas (addicts), salmonella (sickle cell) • Differential Diagnosis Neoplasm • FOGMACHINES/FEGNOMASHIC • Lymphoma, leukemia, mets, multifocal osteogenic sarcoma
CASE #22 - DISCUSSION • Differential Diagnosis Inflammation • Differential Diagnosis Trauma/Other • Fracture with healing • FEGNOMASHIC/FOGMACHINES • Diagnosis: Cocci Osteomyeltis • Short Read: • Brodie abscess subacute or chronic osteomyeltis • Involucrum is a shell of periosteal reactive bone formation surrounding infected bone (sequestrum) • Sequestrum is a segment of necrotic bone with organisms separated from viable bone by granulation tissue • Cloaca are holes in involucrum through which pus extrudes • MRI low signal dark on T1, high signal bright on T2
CASE #23 - DISCUSSION • Findings • Bilateral symmetrical , postage stamp edge erosions, sclerosis • No squaring of T12/L1 vert bodies, ivory corner, no ankylosis • Normal mineralization, no syndesmophytes • Differential Diagnosis Infection • Septic arthritis (bacterial, fungal, TB) • Differential Diagnosis Neoplasm • Differential Diagnosis Inflammation • Ankylosing spondylitis • IBD, Psoriatic, Reiter’s, RA, CPPD, Gout, OCI
CASE #23 - DISCUSSION • Differential Diagnosis Trauma/Other • Post traumatic secondary OA • Diagnosis: Ankylosing Spondylitis • Short Read: • Least erosive most ossifying of all inflammatory arthropathies • RF neg; HLA-B27 antigen positive in many especially caucas • Fibrocartilage (1 mm) iliac first, Hyaline (3-5 mm) sacral later • Anteroinferior half to 2/3 is a true synovial joint; posterosuper half to 1/3 is a cleft between bones with ligs (no cartilage) • DDX 1) width of joint space 2) presence and type of erosions 3) presence and type of sclerosis 4) presence and type of bony bridging 5)distribution of above changes • Septic unilateral; AS, IBD, CPPD, OCI bilateral symmetrical; Psoriatic, Reiter’s, Gout, OA bilateral asymmetrical
CASE #29 - DISCUSSION • Findings • Fragmentation of tibial tuberosity, soft tissue swelling • Thickened patellar tendon indistinct posterior margin • Differential Diagnosis Infection • Osteomyelitis (stretch) • Differential Diagnosis Neoplasm • Differential Diagnosis Inflammation • Apophysitis tibial tubercle • Differential Diagnosis Trauma/Other • Osgood-Schlatter disease