User Tools

Site Tools


Table of Contents

Contrast Rxn

Don't freak out



  • Extraperitoneal cavity: contiguous with retroperitoneal space
  • Retropubic space of Retzius: contiguous with posterior pararenal space + extraperitoneal fat
  • Perineum: below pelvic diaphragm
  • Parametrium: contained within broad ligament
  • Denonvillier’s fascia: positioned between prostate and rectum


  • Combination of coritcal & medullary nephrocalcinosis suggests primary oxaluria

Grades of Vesicoureteral Reflux

Grades of Vesicoureteral Reflux

Cortical Nephrocalcinosis (COAG)

  • Cortical Necrosis (Acute)
  • Oxalosis
  • Alport Syndrome
  • Glomerulonephritis (Chronic)

Medullary Nephrocalcinosis (MARCH)

  • Medullary Sponge Kidney
  • Alkali Excess
  • RTA (Type 1, Distal), Renal Medullary/Cortical Necrosis
  • Chronic Glomerulonephritis
  • Hyperoxaluria, Hypercalcemia (Hyperparathyroidism), Hypercalciuria

Papillary Necrosis (POSTCARD)

  • Pyelonephritis
  • Obstruction
  • Sickle Cell
  • TB/Trauma
  • Cirrhosis
  • Analgesic Nephropathy
  • Renal Vein Thrombosis
  • Diabetes

Diffusely Hyperechoic Kidneys (HIV MAN)

  • HIV
  • Inflammation
    • Glomerulonephritis
    • HTN, DM
  • Vascular
    • SLE / Vasculitis
  • Multiple Myeloma
  • Acute Tubular Necrosis / ARPCKD
  • Nephrocalcinosis
  • ESRD
  • Hemolytic Uremic Syndrome

Bilaterally Enlarged Kidneys (TIM VPC)

  • Tumor
    • Leukemia / Lymphoma
    • Myeloma
  • Inflammation (acute)
    • Glomerulonephritis
    • Interstitial Nephritis
    • ATN
  • Metabolic
    • Amyloid
    • Diabetes
    • Gaucher's
    • Acromegaly
  • Vascular
    • Bilateral renal vein thrombosis
  • Polycystic Kidney Disease
  • Collagen Vascular Disease

Bilaterally Small Kidneys (IR RAS)

  • Inflammation (chronic)
    • Pyelo, Glomerulonephritis, Interstitial Nephritis
  • Reflux (chronic infection)
  • Bilateral renal artery stenosis

Unilaterally Small Kidney (VOX HS)

  • Vascular (RAS / RVT)
  • Obstruction
  • XRT
  • Hypoplasia
  • Subcapsular hematoma (chronic)

Urethral Stricture

  • iatrogenic
  • post-infectious (gonococcal or non-gonococcal)
  • non-infectious irritation (chemical or Reiter's)
  • traumatic injury
  • neoplasm (long, irregular stricture ± fistula)

Bosniak Classification

  • Category I - No atypical features
    • US - anechoic without internal echoes, with good thru transmission and a barely perceptible but well defined wall
    • CT - fluid density, no enhancement and imperceptible wall
  • Category II - homogeneously hyperdense cyst that is not enhancing, or thin (<1mm) septations or thin wall Ca+
    • must be 3 cm or less in diameter, have one quarter of its wall extending outside the kidney so the wall can be assessed, and be nonenhancing after contrast material is administered
  • Category IIF - minimally complicated cysts that need follow-up
    • not well defined by Bosniak but consists of lesions that do not neatly fall into category II
    • have some suspicious features that deserve follow-up up to detect any change in character.
  • Category III - true indeterminate cystic masses that need surgical evaluation, although many prove to be benign
    • thicker septations or multiloculated, coarser Ca+ or solid component that is not enhancing
    • may show uniform wall thickening, nodularity, thick or irregular peripheral calcification, or a multilocular nature with multiple enhancing septa
    • hyperdense lesions that do not fulfill category II criteria are including in this group.
  • Category IV - needs nephrectomy
    • nonuniform or enhancing thick wall, enhancing or large nodules in the wall, or clearly solid components in the cystic lesion
    • enhancement of at least 10 HU

RCC Staging

  • Stage 1 → confined by renal capsule (completely in kidney)
  • Stage 2 → beyond capsule but confined within Gerota’s fascia
  • Stage 3A → extension to renal vein or IVC
  • Stage 3B → positive lymph nodes
  • Stage 3C → both venous extension and adenopathy
  • Stage 4A → grows through gerotas fascia into adjacent organs (other than adrenal)
  • Stage 4B → distant mets

Grading of Renal Lacerations


Ureter & Bladder

DDx Small Bladder (CITRUS)

  • cystitis cystica
  • interstitial cystitis
  • TB
  • rads
  • unused bladder
  • surgery and schistosomiasis

DDx Pear-shaped Bladder (CILLI)

  • Collection - urinoma, hematoma, abscess
  • IVC obstruction
  • Lymphoma / adenopathy
  • Lipomatosis
  • Iliopsoas hypertrophy

DDx for ureteral filling defects

  • Fungus ball
  • Ureteritis cystica → epithelial/ subepithelial cysts due to inflammation or irritation (metaplasia of Brunn’s nests)
  • Clot
  • Fibroepithelial polyp
  • Endometriosis
  • Stone / Sloughed papilla
  • Tumor / TB
  • Leukoplakia: associated with Schistosomiasis; premalignant → squamous cell carcinoma
  • Malakoplakia: chronic gram (-) infection (E. coli #1); ↑ DM → foamy macrophages (Hansemann) with PAS (+) inclusions (Michaelis-Guttman bodies); raised yellow lesions
    • looks like ureteritis cystica

DDx hemorrhagic cystitis

  • viral and bacterial infection
  • drugs - cyclophosphamide (cytoxan)
  • eosinophilic
  • cystitis cystica


  • 1-3 mm outpouchings
  • DDx → calculi / infections / CA (#1 = TCC)

Ureteral TCC

  • Risks: azo-dyes, cyclophosphamide, phenacetin
  • Radiographic:
    • “Wine glass/goblet” deformity (dilated distal ureter)
    • Bergman sign (coiled retrograde catheter)

Ureteral displacement

  • Distribution:
Medial Lateral
Above PelvisRetroperitoneal fibrosis
Retrocaval ureter
(right; at L3)
Psoas hypertrophy
Central tumor
Below PelvisPelvic lipomatosis
Iliac LAD/ aneurysm
Iliopsoas hypertrophy
Hutch diverticulum
Ovarian masses
  • Medial
    • Retroperitoneal fibrosis: drugs (methylsergide, ergotamine); XRT; prior surgery; malignancy; connective tissue disorders
    • Retrocaval ureter (right only)
    • Pelvic lipomatosis: ↑ black males; “tear-drop” or “pear”-shaped bladder; associated with ureteritis cystica
    • Other: hematoma; iliac LAD or aneurysms; adnexal mass; surgery
  • Lateral:
    • AAA
    • LAD; psoas hypertrophy
    • Central pelvic mass
    • Retroperitoneal fat (≠ pelvic lipomatosis)

DDx for ureteral stricture

  • Infection: TB; Schistosomiasis; abscess; fistula
  • CA: metastases; local extension; TCC; lymphoma
  • XRT
  • Inflammation: calculi; instrumentation; stent; endometriosis

DDx for ureteral dilatation

  • Obstruction
  • Reflux
  • Primary megaureter (“beak” sign)

DDx for bladder filling defects

  • Tumor: TCC; adenocarcinoma; squamous cell carcinoma; metastases (pheochromocytoma)
  • Extrinsic masses: BPH; uterus (fibroids); etc.
  • Other: calculus; thrombus; ureterocele (pseudoureterocele due to inflam/ tumor); foreign bodies

Hutch Diverticulum

  • adjacent to UVJ; ↑ vesicoureteral reflux

Bladder Carcinoma

  • Clinical: transitional cell (90% malignant); risks = azo-dyes; phenacetin; cyclophosphamide; focal thickening of bladder wall; perivesical spread; LAD (> 10 mm)
  • Staging:
    • Stage A: limited to mucosa + submucosa
    • Stage B1: superficial muscular layer
    • Stage B2: deep muscular layer
    • Stage C: perivesical fat
    • Stage D: seminal vesicles, prostate, or rectum

Bladder Trauma

  • Contusion: interstitial
  • Extraperitoneal: due to pelvic fracture, dissection into retroperitoneum + scrotum + thigh
  • Intraperitoneal: usually blunt trauma with distended bladder; DX requires adequate bladder distention (> 250 ml)

DDx for Bladder Ca2+ (SCART)

  • Schistosomiasis (↑ squamous cell carcinoma)
  • CA; cyclophosphamide (cytoxan); calculus
  • Alkaline encrusting cystitis
  • Radiation
  • TB


Urethral Anatomy

Anatomy (male)

  • Anterior = penile + bulbous (penoscrotal junction)
  • Posterior = membranous (between inferior margin of verumontanum + tip/ cone of bulbous urethra) + prostatic
    • Cowper’s glands: contained within membranous urethra with ducts entering the bulbous urethra
    • Glands of Littré: located primarily along dorsal penile urethra → infections (gonococcus; chlamydia)

Urethral Injuries

  • Clinical: risks = pelvic trauma (especially multiple pelvic fractures); absence of blood at meatus does not exclude urethral injury → RUG
  • Subtypes:
  • Type I: posterior urethra stretched
  • Type II: posterior disruption (above urogenital diaphragm)
  • Type III: anterior + posterior disruption
  • Type IV: bladder neck injury with extension to urethra
  • Type IVa: periurethral extravasation with intact urethra
  • Type V: anterior disruption (“saddle” injury); ↑ bulbous urethra

Female Urethral Diverticulum

  • Clinical: most often acquired due to infection of Skene’s glands; ↑ posterior wall; SXS = dysuria + dribbling + dyspareunia (3 D’s);

TX = surgical resection (diverticulectomy)

  • Radiographic: focal outpouching along posterior urethra; impression along inferior bladder (= “male prostate”); best seen on MRI
  • Complications: infection; calculi; CA (squamous cell)

DDx for Urethral Strictures (TIICB)

  • Trauma
  • Inflammatory; infections (prostatitis; phlegmon; etc.)
  • Calculus
  • BXO (= balanitis xerotica obliterans): variant of lichen sclerosis et atrophicus (white plaques) → phimosis/ meatal stenosis; premalignant (penile squamous carcinoma)


  • ↑ cryptorchidism (30%) + inguinal hernias (10%)

DDx for Urethral Tumors


  • Fibroepithelial polyp: solitary; pedunculated; attached near veru montanum; ↑ child/ young adult
  • Transitional cell papilloma: ↑ prostatic/ bulbomembranous urethra; ↑ bladder papillomas; older adults
  • Adenomatous polyp: ↑ young men; adjacent to veru montanum
  • Penile squamous papilloma / condyloma acuminata: verrucous lesion in penile urethra; associated with cutaneous disease


  • Squamous cell carcinoma (70%): distal 2/3 of urethra; risks = venereal disease; ↑ stricture (> 80%)
  • TCC (10-20%): posterior 1/3 of urethra; ↑ multifocal
  • Adenocarcinoma (10-20%): arise from periurethral glands (Skene; female) and glands of Cowper/ Littré (male)


Testicular Cancer

  • Clinical: seminomas → orchiectomy + XRT; nonseminomas (radioresistant) → orchiectomy + chemotherapy
  • Staging:
    • Stage I: limited to testes and spermatic cord
    • Stage II: lymph nodes below the diaphragm
    • Stage III: lymph nodes above the diaphragm
      • A: lymph nodes only
      • B: extranodal mets
  • Lymphatic spread: along gonadal veins → renal hilar nodes; external iliac nodes → para-aortic nodes
  • Hematogenous spread: uncommon except for choriocarcinoma
  • Cryptorchidism: located from inferior renal pole to superficial inguinal ring; ↑ risk of torsion (↑ 10x) + malignancy (↑ 50x); usually atrophic

Extratesticular Mass DDx

  • Inguinal hernia
  • Inflammatory mass such as infection, sarcoidosis
  • Benign neoplastic processes such as adenomatoid tumor, epidermoid inclusion cyst
  • Malignant processes such as soft tissue sarcomas, mesothelioma of the tunica, lymphoma, and metastatic disease.

Peyronie's Disease

  • Calcification of tunica albuginea of corpora cavernosa
  • Idiopathic, older men (> 45 yrs old)



  • U/S → hyperechoic central gland = transitional + central zones
  • Transition zone (5%): periurethral → BPH
  • Central zone (25%): ejaculatory ducts
  • Peripheral zone (75%): carcinoma (> 80%); hypoechoic


  • periurethral transitional zone; enlarged, lobulated gland; cystic degeneration; Ca2+; elevation of bladder base; bladder wall thickening and trabeculation

Prostatic Cysts

  • Midline:
    • Mullerian duct: larger; extend superiorly
    • Utricular cyst: smaller; communicate with urethra; ↑ hypospadias
    • Ejaculatory duct cyst: acquired; due to obstruction
  • Eccentric:
    • Cystic prostatitis/ carcinoma
    • Cystic BPH
  • DDX = seminal vesicle cysts → unilateral; ↑ ipsilateral renal agenesis (= Zinner syndrome) > cystic renal disease (APKD), renal ectopia, duplication, ectopic renal insertion

Prostate Carcinoma

  • Clinical: # 2 male CA; enlarged gland with nodules; periprostatic stranding; regional nodes; direct extension to seminal vesicles, bladder; mets to axial skeleton
  • Radiographic: hypoechoic; ↓ T2 lesions in peripheral gland (DDX = prostatitis; fibrosis; hemorrhage)


  • Stage A: nonpalpable
  • Stage B: confined to prostate
  • Stage C: capsular involvement
    • 1: invasion
    • 2: penetration
    • 3: seminal vesicles
  • Stage D: metastases
    • D1: pelvic LN
    • D2: bone; distant LN
  • Treatment: Stage A/B → radical prostatectomy +/- XRT; Stage C/D → hormone therapy +/- XRT

Peritoneal Cavity, Vessels, and Nodes

Fluid in peritoneal cavity

  • Ascites: serous; due to CHF, cirrhosis, hypoproteinemia, venous obstruction; accumulates in greater peritoneal space; density = 10-15 HU
  • Exudative ascites: pancreattis → accumulates within lesser sac; peritonitis; bowel perforation
  • Hemoperitoneum: density > 30 HU; “sentinel bleed” → accumulates at site of hemorrhage
  • Pseudomyxoma peritonei: due to appendiceal mucocele or mucinous cystadenocarcinoma of the ovary (> urachal/ endometrial CA); peritoneum filled with gelatinous mucin; Ca2+


  • due to bowel perforation, pneumothorax, or mechanical ventilation

Peritoneal tumors

  • Peritoneal carcinomatosis:
    • Etiologies: ovarian, pancreatic, gastric, and colon carcinoma
    • Radiographic: malignant ascites; tumor nodules/ Ca2+ → bowel wall nodularity; mesentery; “omental cake”; pouch of Douglas (“Blumer’s shelf); adnexa/ ovaries (Krukenberg tumor)
  • Peritoneal (cystic) mesothelioma: 20-40% in abdomen; ↑ women 30-40 years; irregular thickening of peritoneal surfaces; multilocular cysts; ascites; bowel compression without obstruction
  • Mesenteric lipodystrophy (= retractile mesenteritis): fat-density mass with tethering/ kinking/ angulation of adherent bowel loops


  • Clinical: complications of trauma or surgery; pancreatitis; bowel perforation; commonly located within pelvis, subhepatic and subphrenic spaces
  • Radiographic: loculated fluid collection; thickened walls; gas; thickening of fascia; obliteration of fat planes; ascites; pleural effusions

DDx for cystic abdominal masses

  • Abscess
  • Loculated ascites
  • Pancreatic pseudocyst
  • Ovarian cyst/ tumor
  • Cystic teratoma: fat, water, Ca2+
  • Enteric duplication cysts: lined by GI mucosa
  • Lymphocele: complication of surgery / trauma
  • Cystic lymphangioma: mesenteric / omental

DDx for pelvic cystic masses

  • Ectopic pregnancy: adnexal/ tubal ring
  • TOA: tubo-ovarian abscess
  • Endometrioma
  • Ovarian neoplasms
  • Ovarian cysts
  • Extra-GU origin: abscess; urinoma; duplication/ mesenteric cyst; etc.

Lymph nodes

  • Pathology: lymphadenopathy: > 10 mm in abdomen and pelvis; > 6 mm in retrocrural and porta hepatis regions
  • Hodgkin’s lymphoma: 40% of total; contiguous spread
  • Non-Hodgkin’s lymphoma: 60% of total; noncontiguous spread; ↑ GI involvement

DDx for hypodense intra-abdominal/ retroperitoneal LAD

  • Infection: MAI > TB (↑ AIDS), histoplasmosis
  • Whipple’s disease: glycogen deposition
  • Tumors: lymphoma (post-therapy); nonseminomatous testicular CA; mucinous adenoCA (rare)


  • Hemoperitoneum: density (30-45) HU; (60-80) HU → active bleeding (> 100 HU with contrast); “sentinel clot” → adjacent to injured organ (> 60 HU); free intraperitoneal contrast → bowel/ bladder perforation
  • Pneumoperitoneum: perforated viscous; PTX; mechanical ventilation; post-op
  • Subcapsular hematomas: crescentic → flatten parenchyma
  • Lacerations: jagged, linear low density areas
  • Intraparenchymal hematomas: rounded, low density areas


Retroperitoneal fibrosis

  • ST-encasement of retroperitoneal vessels/ ureters without anterior displacement (DDX = lymphoma); prominent enhancement
  • Drugs: methylsergide; hydralazine
  • Lymphoma
  • Metastases: lung; breast; carcinoid
  • Other: AAA; trauma; surgery; instrumentation
  • Ormond’s disease: idiopathic

DDx for retroperitoneal masses


  • MFH (#1)
  • Liposarcoma (#2)
  • Other: leiomyosarcoma; metastases; RCC/ adrenal extension


  • XGP
  • Neural tumors
  • Lymphangioma; hamangioma; lipoma
  • Teratoma (dermoid)

Retroperitoneal Fibrosis

  • Associated w/
    • aortic aneurysms
    • inflammatory bowel dz
    • urinomas
    • retroperitoneal hematomas
    • aortic and iliac graft procedures
    • infections
    • ergot alkaloids
    • sclerosing cholangitis
    • fibrosing mediastinitis

Waterhouse-Friderichsen syndrome

  • massive, usually bilateral, hemorrhage into the adrenal glands caused by fulminant meningococcemia

Low-density Retroperitoneal Nodes

  • Neoplastic
    • Testicular (particularly teratocarcinoma)
    • Epidermoid carcinoma of GU tract
    • Lymphoma
    • Leiomyosarcoma
  • Infectious
    • Whipple's Dz
    • MAI
dokuwiki\Exception\FatalException: Allowed memory size of 134217728 bytes exhausted (tried to allocate 20480 bytes)

dokuwiki\Exception\FatalException: Allowed memory size of 134217728 bytes exhausted (tried to allocate 20480 bytes)

An unforeseen error has occured. This is most likely a bug somewhere. It might be a problem in the authplain plugin.

More info has been written to the DokuWiki error log.