Homework Dec 15.docx

Gleason Scoring 1. Facts a. Prostate cancer is 2nd most common cancer in men in the world. b. Estimated to be around 300,000 deaths per year. c. Gleason scoring is based on architecture features of prostate cancer. Higher scores are related to worse outcomes. i. Tumors are graded from 1-5 (1 is most differentiated while 5 is least differentiated) ii. Two most prevalent differentiation patterns is used for Gleason score. Add together 1-5 for both types to get composite score. iii. Grade group 1 – gleason score 6 or below iv. Grade Group 2 – Gleason score 3+4 = 7 v. Grade group 3 – Gleason score 4+3 = 7 vi. Grade Group 4 – Gleason = 8 (4+4, 3+5, 5+3) vii. Grade Group 5 – Gleason scores 9-10 (4+5, 5+4, 5+5,) d. Gleason score 6 in Grade Group 1 is still considered prostate cancer. 3+3 is one of the more common forms of prostate cancer (early phase) 2. Treatment a. Most important factors in determining the treatment: i. Anatomic extent (TNM staging) ii. Histologic grade (Gleason score) iii. Serum PSA iv. Potential complications with each treatment modality v. Patient’s age and comorbities b. Very Low Risk/Low Risk – Grade Group 1 (Gleason 6 or below) i. Life exp <20y = active surveillance ii. Life exp >20y = Active surveillance (tx if progresses) OR radiation therapy (external beam or brachytherapy) OR radical prostectomy c. Intermediate Risk – Grade Group 2 or 3 – Gleason score 7 i. Treat with radiation therapy (EB, brachytherapy) OR radical prostatectomy with pelvic LN dissection ii. Active surveillance NOT indicated unless patient elderly and has limited life exp. d. High Risk/Very High Risk – Grade Group 4 or 5 – Gleason 8-10 i. Radiation therapy (EB or combined EB/Brachytherapy) ii. Radical Prostatectomy with extended pelvic LN dissection

Synovial Osteochondromatosis  Define – rare, benign, synovial metaplasia/proliferation causing formation of intraarticular loose bodies made of cartilage which can be ossified. Synovium does not grow properly and forms nodules that can become loose inside the joint. Occurs spontaneously and not inherited. Primary form is from unknown origin while secondary is due to degenerative changes.

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Demographics a. Men 2x more common than women; between age 30-50 Clinical Presentation a. Similar to osteoarthritis (joint pain + swelling + loss of motion) b. May feel fluid in joint, tender to palpation, grinding/popping and nodules can be felt if close to skin. c. Knee is most commonly affected (70%) > hip (20%), elbow > shoulder Pathogenesis a. 3 phases i. Initial – metaplasia forming cartilage nodules in synovium ii. Transition – detachment of nodules (free intraarticular bodies) iii. Inactive – synovial proliferation stopped but loose bodies still in joint. Imaging a. X-ray findings will depend stage of ossification. If no calcification seen (in ~30% cases) then radiograph can be normal or show non specific findings like joint space widening, erosions and osteoarthritic changes. If calcifications present, may see ring and arc calcification pattern which is pathognomonic of chondral calcification. b. CT findings will show loose intraarticular bodies. c. MRI will show T1 with medium-low signal and T2 showing high signal (unmineralized nodules showing chondroid signal) d. Gradient Echo can show blooming artifact.

Ovoid mass anterior to ankle joint below in “rings/arcs” pattern involving chondroid matrix.

xray below showing intra-articular bodies

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Treatment a. Surgery  remove loose cartilage bodies. Sometimes synovium is removed.

Osteomyelitis X-ray findings 1. Adjacent soft tissue swelling and loss of normal flat planes. May see effusion in joint. Early on findings are usually subtle and may not show any obvious signs until ~1week in kids or up to 2 weeks in adults. 2. Etiology a. Newborn – S.aureus, Group B strep and E.coli b. Kids – S. aureus c. Adults – S.aureus, Strep d. Drug addicts – Pseudomonas e. Sickle Cell – Salmonella 3. Pathogenesis a. Hematogenous spread (seen in kids to metaphysis) b. Trauma allowing direct entry c. Soft tissue infection extension into bone 4. Findings on Xray a. Peri-osteal reaction – codman triangle formation b. Endosteal Scalloping c. Loss of body trabecular architecture d. Cortical loss, focal bony lysis e. Regional osteopaenia f. If untreated – sequestrum, involucrum, cloaca. Xray below showing bone destruction of proximal/terminal phalanges of 1st toe. Note cortical destruction. Pathologic fracture also seen (yellow arrow)

Xray below showing bone destruction in 2nd MT head with new bone forming (periosteal reaction)

Venous Thrombosis Treatment a. VTE = DVT and PE b. Mainstay treatment of DVT = anti-coags c. Indications for anti-coags is much stronger for proximal DVT (popliteal, femoral, iliac V. ) than distal due to higher risk for embolization and death. d. Anticoags a. LMW heparin, fondaparinux, rivaroxaban, apixaban – weigh risks of each. Warfarin not given alone as initial anti-coag due to delay in depletion of VitK dep coag factors. Medullary Sponge Kidney a. Define – congenital disorder of kidneys where there are multiple cystic dilations of collecting tubules. Patient has increased risk for kidney stone formation and UTIs.

b. Clinical Presentation a. Most asymptomatic and diagnosed when patient has blood in urine b. If symptomatic, renal colic, stones, recurrent UTIs seen c. Etiology a. Ureteric bud-metenephric mesenchyme interface disruption. d. Imaging a. Medullary nephrocalcinosis (80% cases that can be unilateral or bilateral) b. X-ray – pyramidal medullary calcifications in clusters. c. CT – delayed post contrast CT  paint brush appearance in renal medulla regions. White Pyramid Sign may be seen on non-con CT KUB. d. IV pyelogram  bouquet of flower appearance e. Ultrasound  echogenic medullary pyramids Non-con CT below showing clusters of calcification @ corticomedullary junction bilaterally. Key finding = pyramidal calcification

calcifications seen in clusters where pyramids are located bilaterally (below)

CT noncontrast showing small calcifications in renal calculi (non-obstructing)

Mesenteric Root Edema a. Misty mesentery – term for CT showing mesenteric fat that has increased attenuation. b. Causes include inflammation, edema, lymphatic accumulation, hemorrhage, tumor infiltrating, and fibrosis. c. Imaging a. Mesenteric panniculitis seen below on axial CT

Mesentery edema and inflammatory changes seen below with fat stranding and increased attenuation within mesentery

Dactylitis a. Define – sausage digit, inflammation of digit that may be painful. Sausage digit: Fusiform swelling due to soft tissue inflammation which may be due to underlying arthropathy or dactilytis. b. Dactylitis comes from Greek word Daktylos which means finger. c. Seen in a. Seronegative arthropathies – psortiatic arthritis, ankylosing spondylitis b. Sickle cell disease (due to vaso-occlusive crisis) c. TB d. Leprosy e. Reactive Arthritis – due to synovitis d. Imaging a. TB dactilytis shown below on xray

Sickle cell dactilytis shown below

Madelung Deformity a. Define – malformed wrists/wrist bones and short stature due to defect in development of ulnar 1/3 of the epiphysis of distal radius. Causes radial shaft to bow with increase in interosseous space + dorsal subluxation of distal radioulnar joint. Can be bilateral in about half of patients. b. Epidemiology a. F > M c. Clinical Presentation a. Late childhood/early adolescence. Decreased grip strength and pain in wrist d. Pathogenesis a. Premature closure of failed development of ulnar portion of distal radial epiphysis. Medial and anterior parts of distal radius do not grow. Radius is therefore shortened and relatively ulna is larger. b. Associations include Leri-Weill syndrome (dyschondrosteosis), Turner Syndrome, Achondroplasia, Ollier disease (multiple enchondromas) e. Radiographic findings a. Dorsal + Radial bowing of radius b. Failed ossification of ulnar part of distal radial epiphysis c. V shaped proximal carpal row d. Dorsal subluxation of distal radio-ulnar joint.

Note xray below shows short 4th metacarpal and madelung deformity (patient is girl with turner syndrome). Note there is also a positive metacarpal sign due to shortened 4 th metacarpal. Line drawn from head of 4th and 5th metacarpals intersects with head of 3rd metacarpal.

Short 4th Metacarpal a. Seen in: a. Idiopathic b. Osteomyelitis c. Tuberculosis d. Pseudohypoparathyroidism e. Traumatic f. Turner Syndrome g. Uncommon causes include Gorlin Syndorme and Idiopathic Juvenile Arthritis b. Plain radiograph shows metacarpal sign. Positive sign seen in 10% normal patients. Xray below shows negative metacarpal sign.

Positive metacarpal sign due to shortened 4th digit

Acromelia, Rhizomelia, Mesomelia

a. Acromelia – Dwarfism where shortening is mostly in distal segments of limbs b. Mesomeila – middle segments mostly involved (langer mesomelic dysplasia, Robinow syndrome)

c. Rhizomelia – proximal segments mostly involved (achondroplasia). Xray below showing bowing and short bones in the legs with champagne glass pelvis.

Pseudotumor – Minor fissure a. AP and lateral xray showing pseudotumor due to fluid within the minor fissure.

Minor fissure labeled at A

Levels of Obstetrical US a. Level 1 a. Growth/Position of fetus b. Position of placenta c. Amnionic Fluid Amount b. Level 2 a. Fetal HR b. Fetal Mvmt c. Number of fetus d. Presentation/Lie of fetus e. Amniotic fluid vol. f. Placental location g. Fetal measurements h. Fetal anatomy i. Uterus, Cervix and ovary eval Uterine Didalphys a. Define – malformation where uterus appears as paired organ due to failure of mullerian duct fusion. US shows double uterus and two separate cervix. Each uterus has its own horn with fallopian tube and ovary. b. US below shows uterine didelphys

c. Clinical relevance is that women with this condition have higher risk for malpresentation and premature birth. Acardiac Twinning a. Define – hemodynamically disadvantaged non-viable twin that gets atrophied due to twin reversed arterial perfusion. Parasitic twin that does not develop proper heart. b. Epidemiology – 1 in 100 monozyogtic twin pregnancies. c. US findings – fetal biometric discordance, fetal anasarca, retrograde supply of desat. Blood to upper torso and head  malformation of heart, head and upper torso that are completely absent or deficient. Umbilical cord may be short of acardiac twin.

Dichorionic Diamniotic – each twin has its own chorionic and amnionic sacs. Most commonly dizygotic twin pregnancy but can occur with monozygotic as well. a. Epidemiology – 75% of all twin pregnancies b. Pathophysiology – 2 ova fertilized independently by 2 sperm  2 zygotes c. US shows presence of two gestational sacs with thick echogenic chorion surrounding each of the embryos. There is also thick inter-twin membrane and twin peak sign. US below shows triangular peak of villi extending from placenta into the intertwine membrane.

Twin peak sign below (placenta insinuating between layers of membrane at edges)

Monochorionic Diamniotic – subtype of monozygotic twin pregnancies. Single chorionic sac but two amniotic sacs + 2 yolk sacs. a. Epidemiology – 75% of monozygotic twin preg. (1:400) b. Pathophysiology – separation of single zygote at 4-8 days (blastocyst stage) c. US shows single placenta and inter-twin membrane (T-sign). Absent twin peak sign. US below showing single gestational sac, two yolk sacs and two fetal poles.

Monochorionic Monoamniotic – subtype of monozygotic twins, single chorionic sac + single amniotic sac + single yolk sac. a. Epidemiology – 5% monozygotic twin preg. (1:10,000) b. Pathophysiology – separation of single ovum at 8-13d c. US shows twin pregnancy with 1 gestational sac and 1 yolk sac. No inter-twin membrane. No twin peak sign.

Conjoined Twins – failure of zygote to separate after 13w a. Epidemiology – 1:50,K – 1:200K. F > M in 3:1 ratio b. Pathophysiology – Conjoined twins are monozygotic, monoamniotic and monochorionic. Failure of complete separation of embryonic plate. c. US shows lack of separating of intertwine membrane. Non separable skin contours and joined fetal bodies. Fetal heads at same level.

Cholodocholithiasis a. Epidemiology – 6-12% of population. Stones more common in females. b. Clinical presentation – often asymptomatic. May present with biliary colic. c. Imaging a. US may show stone as echogenic rounded focus. Dilated bile duct >6mm + 1mm per decade over 60 or >10mm if post cholecystectomy

b. CT may show target sign (hyperattenuating stone with hypoattenuating bile/mucosa surrounding it), rim sign (stone outlined by thin shell of density), crescent sign (bile outlining luminal stone), or calcification of stone (only 20% stones are high density)

c. MRI showing hypoattenuating stone within common bile duct

d. Treatment a. ERCP with sphincterotomy. Complication of pancreatitis can occur. MRCP vs ERCP a. MRCP (unlike ERCP) does not require contrast to be given in ductal system and is non interventional. Gold standard for diagnosis of choledocholithiasis and replaced ERCP largely. a. Based on the idea that stationary fluid gives of high signal intensity (T2 weighted) while flowing blood gives little signal. Bile therefore appears hyperintense.

b. ERCP – endoscope passed to first part of duodenum where contrast is injected into ducts in biliary tree/pancreas to check for stones. Can be used for therapeutic use to remove stones. a. Positive when imaging shows filling defect and dilation of duct indicating stone.

c. Stones that are <5mm in diameter may pass spontaneously. Tarsal Coalition a. Define – complete/partial union between 2+ bones in midfoot and hindfoot. Developmental fusion (congenital) with presentation in adolescence usually. Male: Female 4:1 ratio. 50%~ cases are bilateral. b. Clinical Presentation – tarsal tunnel syndrome i. Peroneal tendon spasm ii. Worsening pain iii. Ball/socket tibio-talar joint iv. Pes planus c. Pathophysiology – 3 types – due to incomplete segmentation during development. i. Bony (synostosis) ii. Cartilage (synchondrosis) iii. Fibrous (Syndesmosis) d. Imaging – 90% are calcaneonavicular or talocalcaneal. Calcaneonavicular coalition

Talocalcaneal coalition

Peri-tonsillar abscess a. Imaging findings a. CT – rim enhancing fluid collection within enlarged/inflamed tonsil CT below showing fluid collection + soft tissue swelling in right tonsillar fossa

CT below showing hypoattenuating lesion w/ peripheral enhancement

b. Tx requires surgical aspiration or I&D. (tonsillitis usually managed with antibiotics)