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141 Cards in this Set

  • Front
  • Back

name the phases of ct for renal masses

what cancer is 3 to 4 times more common in horseshoe kidney
what sructures surround the isthmus of a horseshoe kidney
aorta and inf mesenteric artery
renal ca mets go to what 3 places
what is an oncocytoma
a benign solid tumor arising from the prox renal tubule
what is an angiomyolipoma
a benign tumor composed of blood vessels,smooth muscle, and fat
what disease is assoc with aml
tuberous sclerosis
do aml lesions contain calcifications
ct findings with simple renal cysts
sharp margination
no perceptable wall
homogenous attenuation
water density
increase in size 6%/yr
what criteria are used for the staging of rcc
what is the name for the category of cystic renal masses
what is von hippel-lindau disease
AD, hemangioblastoma of the cerebellum, retina, and spinal cord. often assoc with pckd, pheo, rcc
what is tuberous sclerosis
AD. pckd,aml, hamartomas of skin retina, and brain
what is pyonephrosis
acute infection with pus in an obstructed collecting system
what is emphysematous pyelitis
gas confined to the renal pelvis and calyces
what is emphysematous pyelonephritis
severe diffuse pyelonephritis that occur in pts with dm and obstruction
what is the number one cause of death from ID in the world
how long is the typical ureter
what muscle does the ureter lie on
what is the upper level of nl for a ureter
3 mm
what is the most common anomaly of the urinary tract
duplication of the ureters
complete ureteral duplication is associated with what
ectopic insertion
ectopic ureteroceles
vesicoureteral reflux
what is the Weigert-Meyer rule
that the ureter draining the upper pole of the kidney has fewer calyces and inserts into the bladder medial-inferiorly
renal stones are seen on what % of plain radiographs
What are the 2 MC kinds of stones
73% Ca oxalate and phosphate
What are Struvite stones and what are they associated with
mgal phosphate
What are crystalline Stones
Seen with protease inhibitors. non-opaque
what are white pyramids
renal pyramids in a pt who is dehydrated may be high attenuation
what is the MC site for an impacted stone
Which stones are likely to require surgery
>5mm/prox ureter
tissue rim sign
halo of soft tissue that surrounds the ureteral stone
What may be a subtle sign of acute obstruction
the unilateral absence of white pyramids
what are phleboliths
calcifications that originate in thrombi within pelvic veins
what are phlebolith findings
round/central lucency/tail sign-an uncalcified vein extending from the phlebolith/<311 H
DDX of ureteral obstruction without a stone
passed stone/pyelo/stricture/tumor/crystalline stone
what are the 2 areas of the adrenal and what hormones do they secrete?
cortex: steroid hormones including, cortisol, aldosterone,androgen,estrogen
medulla: catecholamines
how long are the nl limbs of the adrenals and how thick
4 to 5 cm, 10 mm
what % of pts with adrenocortical carcinoma have hyperfunction and what is the MC syndrome?
50%, Cushing
What are 2 ID causes of adrenal calcifications and what syndrome are they associated with?
tb and histoplasmosis, Addison's
Which adrenal tumors calcify in children?
neuroblastoma and ganglioneuroma
What is Wolman's DIsease?
rare AR, calcified enlarged adrenals, hepatosplenomegaly
What is Conn's Syndrome?
primary hyperaldosteronism, 80% caused by hyperfunctioning adenoma
What is pheochromocytoma? what does it secrete? where is it located
catecholamine secreting tumor arises from chromaffin cells in the synpathetic nervous system. 90% benign unilateral in the adrenal medulla
Where do 10% of extra-adrenal pheochromocytomas arise?
Organ of Zuckerkandl near the origin of the Inferior mesenteric artery
what is the difference in lipid location between benign adenomas and myelolipomas?
benign lipid is ntracytoplasmic. in myelolipomas lipid is macroscopic and within fat cells
Which tumors metastisize to the adrenals?
lung, breast, and melanoma
Most adrenal tumors larger than______
are malignant?
5 cm
Benign adenomas have an enhancement of ____.
10 H, <2 H is 100% sensitive
relative % washout of ___% is indicative of benign adenoma
Nabothian Cyst
chronic cervicitis ==> inflammatory stenosis of cervical glands ==> retention ==> cyst


* cystic mass of cervix
* ectopic pregnancy
* adenomyosis
* age: 10 - 30
* occur in young kids before physeal plate closes

* epiphysis
* XR: lucency in epiphysis, speckled calcifications
* 25-50% calcify
Weigert-Meyer rule
applies to duplex collecting systems

* upper-pole ureter
o obstruction ==> hydronephrosis
o inserts more inferiorly and medially in bladder
o may insert into urethra, vagina, etc.
+ males not incontinent: insertion above ext. sphincter
o associated with ureterocele

* lower-pole ureter
o reflux ==> pyelonephritis

see also: "drooping lily" sign
drooping lily sign
appearance of renal pelvis with duplicated collecting system

* upper pole moiety obstructs, becomes hydronephrotic
* ==> compresses lower-pole moiety and pushes it downward

see also: Weigert-Meyer rule
xanthogranulomatous pyelonephritis (XGP)
* big kidney
* non-functioning (80%)
* dilated calyces, thin cortex
* calculi (often staghorn)

* adult females
* usually unilateral
* Gram-negative infection, esp. Proteus mirabilis

* symptoms: fatigue, low fever, dysuria, flank pain
* pathology: granulomata in parenchyma with foam cells, cholesterol slits, fibrosis, atrophic glomeruli

* atypical focal form: may resemble focal Ca
gestational trophoblastic disease
* complete (classic) mole

* partial mole

* choriocarcinoma
o --> pulm mets
hydatiform mole
* trophoblastic proliferation with avascularity of chorionic villi
* marked edema and enlargement of chorionic villi

* severe eclampsia prior to 24 weeks
* 1st trimester bleeding
* abnormal elevation of beta-hCG
* passing grapelike vesicles per vagina

* uterus large for dates (50%)
* hyperechoic intrauterine tissue interspersed with numerous punctate hypoechoic areas (hydropic villi)
* in 25% atypical appearance: large hyperechoic areas (blood clots) and areas of cystic degeneration; resembles incomplete abortion
* thick hyperechoic rim around central anechoic zone
* bilateral theca lutein cysts (18-37%)
* 5% of gestational trophoblastic disease
* excessive trophoblastic proliferation without villous structures

* continued bleeding
* elevated hCG after expulsion of molar or normal pregnancy (25%)


* mixed hyperechoic pattern (hemorrhage, necrosis)
* radiodense pulmonary masses with hazy borders due to hemorrhage
* hemorrhagic brain mets
* hyperechoic hepatic foci
tuberous sclerosis
(Bourneville disease)
autosomal dominant phakomatosis
classic triad: seizures, retardation, adenoma sebaceum

* calcified subependymal hamartomas
* uncalcified tubers in cerebral cortex
* enhancing lesion ==> malignant transformation to
giant cell astrocytoma

associated with:

* skin lesions
* angiomyolipoma
* increased risk of renal cell Ca
What is the eponym for tubreous sclerosis?
Bourneville disease
Gartner duct cyst
cyst in lateral wall of vagina

* remnant of wolffian duct
wolffian (mesonephric) duct

* vas deferens
* vasa efferentia


* Gartner duct cyst
* hydatid cyst of Morgagni
* epoophoron
* paroophoron

Cf: mullerian (para-mesonephric) duct
hydatid cyst of Morgagni
paraovarian cyst near fimbria or broad ligament

* serous fluid
* no clinical significance

* wolffian duct remnant (probably)
mullerian (para-mesonephric) duct

* fallopian tubes
* uterus
* vagina


* appendix testis
* prostatic utricle


* mullerian agenesis ==> absent uterus + vagina
* incomplete fusion ==> bicornuate/double uterus, double vagina
* both a/w renal agenesis
medullary cystic kidney disease
* mode of inheritance uncertain
* usually affects young adults (early 20s)
* associated with red or blond hair (!!)

* causes salt wasting, polyuria, azotemia
* affects both kidneys
* progressive ==> pts need dialysis or transplant
polycystic kidney disease
* autosomal recessive ("childhood") form:
o Potter I; incidence 1 : 10000
o affects both kidneys and liver (related to age of onset)

renal cysts periportalfibrosis
neonatal +++ +
infantile ++ ++
juvenile + +++

* autosomal dominant ("adult") form:
o Potter III; incidence 1:500
o no periportal fibrosis
o cysts in liver (in 50%), pancreas, spleen, lung
o berry aneurysms (15%)
Arise from oncocytes in the proximal tubule
resect sec to malignant potential
impossible to differentiate from RCC
May have central stellate scar on CT
Wegener granulomatosis
* sinuses and upper respiratory tract (100%)
o mucoperiosteal thickening
o rhinorrhea and epistaxis
o may destroy bone + cartilage

* lungs
o necrotizing granulomata
o multiple round nodules (2 mm - 9 cm)
o alveolar infiltrates
o may cavitate

* kidneys (83%)
o glomerulonephritis ==> necrosis of capillary tuft

* generalized necrotizing vasculitis of arteries + veins
o auto-immune: basement membrane
o almost always involves lungs

* M = F, 30-50 y/o
* sx: cough, hemoptysis, fever, wt loss, multiple resp. infections
* tx: cyclophosphamide, corticosteroids (90% complete remission)
* 90% mortality within 2 years if untreated (renal>pulmonary failure)
Supparative Leiomyoma
results from bacterial seeding of a necrotic fibroid.
It is a rare complication of fibroid disease.
Alkaline-encrusted cystitis and pyelitis
Calcifications in the urothelium on a noncontrast CT should be suspicious for encrusted urothelial plaques, which can occur anywhere throughout the collecting system, ureters, and bladder.
The mucosal encrustations are induced by urea-splitting bacteria, most commonly Corynebacterium. Alkaline urine is a clue.
Look out for this disease process in immunosupressed patients and especially renal transplant patients
fibromuscular dysplasia (FMD)
"beaded" segment of artery

medial type most common
F > M

renal arteries
most common vessels
R > L
mid + distal 1/3 (DDx: atherosclerosis - ostium/proximal)
renal agenesis
associated with
duplicated vagina and/or uterus (mullerian duct anomaly)
seminal vesicle cysts
What is the Weigert-Meyer rule
in complete duplications of the renal collecting system, the upper pole ureter is the ectopic ureter and its orifice inserts inferomedially in the bladder in relationship to the orthotopic lower pole ureter.

the position of each ureter insertion into the bladder tends to be the inverse of the position of the renal segment drained

upper pole: stenosis/hydro
lower pole: reflux
radiolucent defect in the renal pelvis generates a diverse differential diagnosis which includes
radiolucent stone, neoplasm (most often transitional cell carcinoma), blood clot, technical underfilling, crossing vessel, aberrant papilla, sloughed papilla, pyelitis cystica, fungus ball, cholesteatoma, or gas
DDX Medullary Nephrocalcinosis
medullary sponge kidney,
renal tubular acidosis (RTA) (Type 1, distal), hyperparathyroidism (or other hypercalcemic states)
DDX cortical nephrocalcinosis
The two most common etiologies for development of this finding are chronic glomerulonephritis and acute cortical necrosis.
Other causes of cortical nephrocalcinosis include hyperoxaluria, Alport's syndrome, methoxyflurane (Penthrane) anesthesia, or ethylene glycol ingestion. It may also be seen in a transplanted kidney as a late complication of chronic rejection
DDX Striated Nephrogram
While obstruction is the most common cause of the striated nephrogram encountered clinically, it has also been reported with pyelonephritis, renal contusion, and hypotension.
Differential diagnosis for the unilateral small kidney includes
renal ischemia (global atrophy with normal collecting system), reflux injury (parenchymal loss more striking in the poles with abnormal subtending calyx) or papillary necrosis (wavy renal outline and uneven involvement of calyces, often bilateral, with characteristic calyceal changes). Less common causes include hypoplasia, radiation, and the aftermath of unusually severe acute pyelonephritis.
IV urographic findings of renal artery stenosis
, since they may be seen in patients undergoing this study for other reasons. The involved kidney is usually decreased in size with a smooth contour. The collecting system shows delayed opacification with, paradoxically, an increased density and delayed emptying of the contrast material. These findings are illustrated in Films 10 and 11 in a patient with right renal artery stenosis. Notching of the pelvis and proximal ureter from enlarged collateral arteries may also be noted. Calcification of the atherosclerotic plaque is occasionally noted. Any combination of the above findings may be seen.
causes of congenital aneurysms
include atherosclerosis (the most common cause), inflammatory disease (mycotic aneurysms), fibromuscular disease, and, rarely, trauma.
Causes of Urinomas
causes include percutaneous nephrostomy, posterior urethral valves, disruption of the renal pelvis or calyces in trauma or ureteroneocystostomy breakdown in a renal transplant, obstructing stone or blood clot, or periureteral fibrosis. The bladder and retrovesical anastomoses account for the sites in two-thirds of renal transplant patients
DDX Urinoma
renal sinus and cortical cysts, and pseudocysts arising from retroperitoneal processes, e.g., pancreatitis.
differential diagnosis of simple renal cysts
calyceal diverticulum, obstructed calyx (hydrocalyx), cystic renal cell carcinoma, and early autosomal dominant (adult) polycystic kidney disease. In some parts of the world renal hydatid cyst must also be considered
differential diagnosis for a septated renal cyst includes
inflammatory cyst, hemorrhagic cyst, multilocular cystic nephroma, and cystic renal adenocarcinoma
differential diagnosis of parapelvic cyst includes
peripelvic cyst, calyceal or pelvic diverticulum, small renal sinus urinoma, aneurysm, and hydronephrosis.
The differential diagnosis of ADPCKD includes
multiple bilateral simple renal cysts, acquired cystic disease of dialysis, tuberous sclerosis, lymphoma, renal metastases, bilateral renal cell carcinomas either as part of von Hippel-Lindau disease or sporadic and medullary cystic disease.
Complications of autosomal dominant (adult) polycystic kidney disease (ADPCKD) are common and include
intracystic hemorrhage (which is very common); perinephric hemorrhage; intracystic infection; pyelonephritis; and collecting system obstruction secondary to calculi, blood clots, and large cysts. Associated symptoms are flank pain due to capsular distention, urinary tract infection or, renal colic. Cyst rupture with retroperitoneal hemorrhage from relatively minor trauma is not uncommon in ADPCKD.
differential diagnosis of ADPCKD includes
multiple bilateral simple renal cysts; acquired cystic disease of dialysis; tuberous sclerosis; bilateral renal cell carcinoma, including patients with vonHippel-Lindau disease; lymphoma; bilateral renal metastases; and medullary cystic disease. Perinephric hemorrhage is commonly associated with renal adenocarcinoma, angiomyolipoma, and vasculitides, particularly polyarteritis nodosa and bleeding diathesis.
differential diagnosis of acquired cystic kidney disease of dialysis includes
multiple bilateral simple renal cysts, autosomal dominant (adult) polycystic kidney disease, von Hippel-Lindau disease, and tuberous sclerosis
Small kidneys, especially those which are hyperechoic, are the common end-point of many different renal parenchymal diseases. Diseases which cause this response include
(1) chronic glomerulonephritis (as in Film 2), (2) arteriolar nephrosclerosis, (3) late diabetes mellitus (as in Film 1), (4) medullary cystic disease, (5) papillary necrosis, (6) amyloidosis (late), and (7) hereditary chronic nephritis.
Normal- to large-sized hyperechoic kidneys can reflect many renal parenchymal disorders. The differential diagnosis includes
acute glomerulonephritis; Goodpasture's syndrome; lupus nephritis; diabetes mellitus; and interstitial diseases, including (1) infectious inflammatory (e.g., acute pyelonephritis) and noninfectious inflammatory immunologic causes (e.g., interstitial nephritis) and (2) infiltrative causes (e.g., amyloidosis). AIDS Nephropathy.
renal adenocarcinoma, oncocytoma, and complicated renal cyst.
differential diagnosis of renal adenoma includes
differential diagnosis of oncocytoma includes
renal adenocarcinoma, lymphoma, and metastases.
differential diagnosis of angiomyolipoma includes
renal cell carcinoma, sinus lipomatosis, retroperitoneal liposarcoma, lipoma, and teratoma.
Hypervascular kidney lesions
renal transitional cell carcinomas and some metastases can be hypervascular and appear similar to the angiographic appearance of RCC. In addition, benign processes such as angiomyolipoma and oncocytoma are typically hypervascular, mimicking RCC.
syndromes in which renal cysts are found as part of the constellation of abnormalities.
These disorders include von Hippel-Lindau disease (VHL), tuberous sclerosis, neurofibromatosis, Caroli's disease, autosomal dominant polycystic kidney disease, autosomal recessive polycystic kidney disease, and medullary cystic disease. Of these, VHL is the one in which the renal cysts have the most significance.
differential diagnosis of the metastatic disease to the kidney includes
other processes which caused wedge-shaped areas of underperfusion, namely, acute pyelonephritis and segmental infarct. Less likely considerations are lymphoma, infiltrating transitional cell carcinoma, and atypical renal cell carcinoma.
DDX hyperechoic normal-sized or enlarged kidneys include
HIV assoc nephropathy, acute glomerulonephritis, Goodpasture's syndrome, systemic lupus erythematosus, and diabetes mellitus
Manifestations of Chronic renal inflammation
including renal sinus lipomatosis, calculi formation, xanthogranulomatous pyelonephritis, malakoplakia, and squamous metaplasia.
differential diagnosis for calyceal distortion and parenchymal scarring includes
papillary necrosis, analgesic abuse, persistent fetal lobations, nephrocalcinosis, ischemia, radiation therapy, renal hypoplasia, and trauma, especially after percutaneous manipulation.
causes for gas in the renal fossa include
Emphysematous pyelonephritis, penetrating injury; instrumentation; barotrauma; asthma; COPD; fistula from the skin, bowel or lung; and therapeutic embolization.
DDX Filling Defects in the renal collecting system
mycetoma, blood clots, nonopaque urinary calculi, urinary tract malignancy, inflammatory debris, and polyps.
DDX perinephric abscess is localized to the anterior paranephric space,
a perforated duodenal ulcer, colon carcinoma, diverticulitis, retrocecal appendicitis, or pancreatitis should be considered
DDX an infection in the posterior paranephric space should prompt an investigation for diseases of the
psoas muscle, spine, lymph nodes, or penetrating injuries.
differential diagnosis for a complex fluid collection in the perinephric space
includes urinoma, lymphocele, and hematoma.
DDX pyonephrosis includes
an obstructed collecting system containing hemorrhage or matrix material, XGP, and extensive urothelial malignancy.
differential diagnosis for multiple hypoechoic or low-attenuation renal masses includes
hydronephrosis with renal calculi, pyonephrosis, tuberculosis, cystic renal cell carcinoma, and lymphoma.
causes of pseudoureterocele formation include
radiation cystitis, bladder floor invasion from adjacent cervical carcinoma, and obstruction of the ureteral orifice following ureteral instrumentation.
precursors for adenocarcinoma of the bladder
Exstrophy of the bladder and cystitis glandularis
DDX pear-shaped bladder
pelvic carcinomatosis, iliopsoas muscle hypertrophy, iliac lymphadenopathy (pelvic hematoma, bilateral pelvic abscesses, lymphocele pelvic lipomatosis, aneurysms, and inferior vena caval obstruction.
DDX Bladder Masses
primary neoplasms (especially verrucous carcinoma); secondary neoplasms; acute (bullous) cystitis; chronic infections (cystitis cystica and glandular, eosinophilic cystitis, malakoplakia); endometriosis; amyloidosis; chemical irritation (cyclophosphamide, organic solvents [e.g., ether], gentian violet); perivesical abscesses (Crohn's disease, diverticulitis, appendiceal); and other lesions too numerous to mention.
DDX Bladder Leiomyoma
neuroma, pheochromocytoma, nephrogenic adenoma, amyloidoma, granular cell tumors, endometriosis, and others. Malignancy must also be considered as lymphoma, leiomyosarcoma, and even a highly atypical transitional cell carcinoma could mimic a leiomyoma.
Congenital diverticula are rare in otherwise healthy children but can be seen regularly in those with
Menkes', Williams', and Ehlers-Danlos syndromes.
When calcification is seen in both bladder and ureteral wall concomitantly, the differential diagnosis can be narrowed to
tuberculosis, schistosomiasis, and amyloidosis.
DDX Cervical Mass
includes a large pedunculated endometrial polyp and, less likely, a malignant neoplasm.
Differential diagnosis for dermoids includes
hemorrhagic cysts, cystic neoplasms, and endometriomas.
Differential diagnosis of a multiloculated adnexal cyst
ovarian cystadenoma or cystadenocarcinoma, an endometrioma, corpus luteal cyst, follicular cyst or, less likely, a hydrosalpinx.
Differential diagnosis of a vaginal mass includes
direct extension from a primary cervical, vulvar, or rectal carcinoma, and vaginal cancer.
differential diagnosis of Gartner's duct cyst
urethral diverticula include vaginal inclusion cysts, ectopic ureters, vaginal duplication, and vaginal hernia.
DDX focal anechoic/cystic processes of the prostate include
abscces, utricular cysts, cystic hyperplasia and the unusual instance of a cystic carcinoma
most common histologic subtype of female urethral cancer is
squamous cell carcinoma which comprises greater than half of all reported tumors
More than half of reported urethral carcinomas in men originate from which portion of the urethra
bulbous urethra
most common urethral cancer,
most common urethral cancer,
differential of Cowper's duct cysts,
periurethral abscess, megalourethra, and even urethral carcinoma are considered to be in the anterior urethral diverticula offer diagnostic confusion.
Causes of retroperitoneal fibrosis
drugs (methysergide, ergotamines, methyldopa, phenacetin, amphetamines), retroperitoneal fluid collections (hemorrhage, urine, contrast media), inflammatory diseases (enteritis, diverticulitis, appendicitis, genitourinary infection, vasculitides), surgery, radiation therapy, perianeurysmal
fibrosis, amyloidosis, and desmoplastic reaction to malignancy (malignant retroperitoneal fibrosis), which may be associated with a number of malignancies including lymphoma, carcinoid, breast, lung, thyroid, GI tract, GU tract, and various sarcomas.
Radiologic appearances favoring malignant causes of periaortic soft tissue include
associated adenopathy, anterior displacement of the abdominal aorta ("floating aorta"), lobular configuration of the periaortic mass, and extension of the periaortic soft tissue cephalad to the renal hilum.
the most common intraluminal venous tumor
most common retroperitoneal tumor in adults
Differential diagnosis of an IVC tumor includes
: liposarcomas (which can usually be distinguished from leiomyosarcomas by the presence of intralesional fat), malignant fibrous histiocytoma, intravenous extension of another primary tumor (e.g., renal cell carcinoma, adrenocortical carcinoma, pheochromocytoma, uterine leiomyomatosis), extrinsic invasion from a malignancy originating in an adjacent organ (e.g., carcinoma of the duodenum, adrenal, liver, etc.), and cephalad extension of pelvic vein thrombosis.
DDX retroperitoneal neoplasms including
neurofibromas and neurilemomas, leiomyosarcomas, liposarcomas (though fat, when present, differentiates this lesion), malignant fibrous histiocytomas, lymphomas, and metastases.
renal angiomyolipoma, although rarely one may encounter a renal teratoma, lipoma, or liposarcoma, RCC fat containing
DDX Causes of retroperitoneal Bleeding
trauma, leaking aneurysms, blood dyscrasias, anticoagulation therapy, hemodialysis, and vascular neoplasms.
most common of the primary retroperitoneal tumor
four histologic types of liposarcoma have been described:
round cell,
Differential diagnosis for retroperitoneal liposarcoma includes
other fatty-containing retroperitoneal processes such as lipomas, lymphangiomas, angiomyolipomas, and cystic teratomas. Retroperitoneal liposarcomas without demonstrable internal fat are indistinguishable by CT examination from other primary and secondary retroperitoneal neoplasms, including metastases, malignant fibrous histiocytoma, leiomyosarcomas, fibrosarcomas, malignant teratomas, and lymphomas.
most common primary tumor of the spleen
Cornual location with less than ? mm of surrounding myometrium is diagnostic for cornual or interstitial ectopic pregnancy.
5 mm
most common urinary anomaly associated with Müllerian duplication anomalies?
Renal agenesis
The most common paratesticular tumor in infants is
mc renal tumor less than 6 months of age
mesoblastic nephroma

What is Robson Staging

RCC tends to invade the renal veins and IVC. Robson stage I is tumor confined within renal capsule.

Stage II: Tumor invasion through renal capsule into perinephric fat but confined by renal fascia.

Stage III: Tumor invasion to regional lymph nodes [b] or renal vein and cava [a] or both [c]. Stage IV- Invasion of adjacent organs [a] or distant metastases [b].