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65 results found

Hypovascular retroperitoneal lesions

Hypovascular retroperitoneal lesions are those which do not enhance in the late arterial and portal venous phases on CT. Some of these lesions may show progressive enhancement in the delayed phase due to their fibrous or myxoid matrix components. Non-enhancing lesions retroperitoneal lipoma r...

Hypervascular retroperitoneal lesions

Hypervascular retroperitoneal lesions are findings that enhance avidly in the late arterial phase with or without washout in the portal venous and delayed phases, on contrast-enhanced CT or MRI. Early enhancement with slow washout sympathetic paragangliomas retroperitoneal paragangliomas - of...

Penile calcification

Penile calcifications are a relatively rare finding. The commonest cause is Peyronie disease. Pathology Etiology Peyronie disease penile calciphylaxis (considered by some to be a form of calcinosis cutis) penile urethral calculus calcinosis cutis of the penis idiopathic calcinosis cutis o...

Renal emphysema

Renal emphysema, or intrarenal gas, refers to the presence of gas within the kidney, with or without extension to the urinary tract. It is a rare finding and only a few differentials need to be considered 1: infections emphysematous pyelonephritis 1 iatrogenic instrumentation biopsy surge...

Ureteral calcification

Ureteral calcification refers to the presence of calcium concretions within the ureteral lumen or wall. Common ureteric calculi Uncommon neoplastic 3 transitional cell carcinoma hemangioma papilloma infections tuberculosis 1 schistosomiasis of the urinary tract iatrogenic radiation u...

Abnormal testicular Doppler flow (differential)

Abnormal testicular Doppler flow (arterial, venous, or both) can be a differential challenge. Always remember that the patient's presenting history helps quite a bit in narrowing the differential. Reduced flow partial testicular torsion (<360 degrees) venous outflow is obstructed first, resul...

Pseudobladder

Pseudobladder refers to a pelvic cystic mass that simulates the urinary bladder. The location of the lesion should allow differentiation from the bladder but if doubt exists and clinical necessity arises, a delayed phase CT/MRI with excreted contrast or Foley catheter-administered retrograde co...

Pseudohydronephrosis

Pseudohydronephrosis (plural: pseudohydronephroses) refers to normal anatomy or non-significant pathologies that may mimic hydronephrosis. There is usually fluid-density material within a dilated part of the urinary tract, but without other signs of obstruction such as retroperitoneal fat strand...

Solitary filling defect of the ureter (differential)

Solitary filling defect within a ureter, as seen on conventional IVU or CT IVU has some differentials, including: within the lumen calculus sloughed papilla blood clot benign polyp within the wall transitional cell carcinoma (TCC) tuberculosis metastasis endometriosis When multiple ...

Renal cortical defect

Renal cortical defects have a variety of causes, and present on imaging as an area of focal cortical thinning or absence of renal cortex, sometimes accompanied by focal caliectasis. Differential diagnosis The differential diagnosis for a renal cortical defect includes 1,2: renal scarring re...

Congenital anomalies of the male urethra

Congenital anomalies of the male urethra include various anomalies due to complex development of urethra. These anomalies can be isolated or in association with other coexisting anomalies. They can be categorized as following: urethral agenesis (or atresia) congenital valves posterior urethr...

Valsalva maneuver

The Valsalva maneuver is the forced expiration of air against a closed airway, resulting in increased intra-abdominal, intrathoracic, and pharyngeal pressure. It can be performed against a closed glottis or by one closing the mouth and pinching the nose while forcibly exhaling. It is commonly u...

Prostatomegaly

Prostatomegaly is a term used to generally describe enlargement of the prostate gland from whatever cause. Usually, the prostate is considered enlarged on imaging when its volume measures beyond 30 cc (mL). Terminology The term prostatomegaly is often used interchangeably with benign prostati...

Extratesticular scrotal mass (differential)

Extratesticular scrotal masses (not arising from testis or epididymis) are mostly mesenchymal in origin and benign 1. Benign lesions lipoma (most common) leiomyoma of the scrotum neurofibroma granular cell tumor angiomyofibroblastoma-like tumor fibrous pseudotumor fibrous hamartoma of i...

Empyema

Empyemas are purulent inflammatory collections within a body cavity. Contrast this with abscesses, which arise within parenchymal tissue, rather than occupying a pre-existing anatomical space. Terminology Colloquially, the standalone term empyema is used to refer to thoracic empyemas but there...

Fat containing renal lesions

There are numerous fat-containing renal lesions, including: renal angiomyolipoma renal cell carcinoma (often has calcifications when contains macroscopic fat) Wilms tumor renal oncocytoma renal or perirenal lipoma/liposarcoma Non-mass lesions may also occasionally contain fat: renal junct...

Cystic lesions around vagina and female urethra

There several cystic lesions around the vagina and female urethra; some of the imaging differential considerations would include: urethral diverticulum Gartner duct cyst: at or above the level of the pubic symphysis anterior to the vaginal wall Bartholin gland cyst: posterolateral to distal v...

HIV/AIDS (genitourinary manifestations)

Genitourinary manifestations of HIV/AIDS are protean and can be divided into: HIV-associated nephropathy renal diseases related to opportunistic infections: CMV, tuberculosis and MAC infections, fungal infections, pneumocystis carinii infection drug-related renal diseases: indinavir-induced ...

Urinary diversion

Urinary diversion is created after the removal of the urinary bladder (radical cystectomy or cystoprostatectomy, usually done to treat invasive bladder cancer). There are three main varieties: neobladder formed from a segment of ileum (i.e. ileal conduit, also known as a "Bricker conduit") th...

Perinephric fluid collection post renal transplant

Perinephric fluid collections post renal transplant are common. The appearance of a perinephric fluid collection after renal transplantation is often non-specific but may be partially differentiated by how long ago the transplant occurred. Radiographic features Early post-transplant period (<4...

Bladder wall thickening (differential)

Differential diagnosis for bladder wall thickening depends on whether the bladder is adequately distended. The bladder wall may be thickened if: >3 mm when distended >5 mm when nondistended If the bladder is not distended, then it is difficult to exclude artifactual thickening from a collapse...

Increased renal echogenicity

Increased renal echogenicity is a non-specific finding but can represent a number of underlying conditions. These include: normal variation renal amyloidosis chronic kidney disease: increased cortical echogenicity sickle cell disease 4 See also echogenic renal pyramids - pediatric renal ...

Right iliac fossa mass (differential)

Right iliac fossa mass is a common clinical presentation and has a range of differentials that need to be excluded. Radiology plays an important role in this differentiation. Differential diagnosis appendicular mass appendicular abscess appendicular mucocele appendicular neoplasms ileoceca...

Urinary bladder diverticulum

A urinary bladder diverticulum (plural: diverticula) is an outpouching from the bladder wall, whereby mucosa herniates through the bladder wall. It may be solitary or multiple in nature and can vary considerably in size. Epidemiology There are two peaks; one at 10 years and the other at 60-70 ...

Epididymal lesions

Epididymal lesions are most commonly encountered on ultrasonography. Most epididymal lesions are benign; malignant lesions are rare. They can comprise of Benign solid lesions adenomatoid tumor of the scrotum: most common epididymal mass 4 epididymal leiomyoma papillary cystadenoma of the e...

Hydronephrosis

Hydronephrosis (plural: hydronephroses) is defined as dilatation of the urinary collecting system of the kidney (the calyces, the infundibula, and the pelvis) 1. Hydronephrosis in fetuses and newborns has specific causes that are covered in a separate article. Terminology The term hydroureter...

Renal vein varices

Renal vein varices (singular: varix) develop for various reasons and are usually asymptomatic. Clinical presentation Renal vein varices are usually asymptomatic. Some patients may present with flank pain and/or hematuria. Pathology Etiology chronic renal vein thrombosis nutcracker syndrom...

Bilateral renal enlargement

Bilateral renal enlargement can arise from a number of causes which include 1,2: Smooth enlargement diabetic nephropathy (common) acute pyelonephritis renal involvement with lymphoma acute interstitial nephritis acute glomerulonephritis acute urate nephropathy vasculitis/autoimmune HIV ...

Intra-abdominal calcification (neonatal)

Intra-abdominal calcification in a neonate can be caused by a number of pathologies that cause calcification within the peritoneal space or within organs. Pathology Etiology Meconium peritonitis The commonest cause is meconium peritonitis which is the result of aseptic peritonitis secondary ...

Medical devices in the abdomen and pelvis

Medical devices in the abdomen and pelvis are important to be recognized, just like medical devices of the chest. We often ignore these devices, considering them to be incidental and non-pathological, however it is essential to be aware of potential complications. Gastrointestinal devices tube...

Congenital renal anomalies

Congenital renal anomalies comprise of vast spectrum of pathologies and include: renal agenesis renal dysgenesis congenital renal hypoplasia congenital megacalyectasis congenital cystic renal disease infantile polycystic renal disease: autosomal recessive polycystic kidney disease (ARPKD):...

Low signal intensity renal parenchyma

There are relatively few causes of low signal intensity renal parenchyma. Causes include: hemolysis paroxysmal nocturnal hemoglobinuria mechanical: malfunctioning prosthetic cardiac valve sickle cell disease infection hemorrhagic fever with renal syndrome (HFRS) vascular disease acute re...

Cystic retroperitoneal lesions

Cystic retroperitoneal lesions can carry a relatively broad differential, which includes: retroperitoneal lymphatic malformation retroperitoneal mucinous cystadenoma retroperitoneal cystic teratoma retroperitoenal cystic mesothelioma pseudomyxoma retroperitonei with cystic change perianal ...

Obstructive uropathy

An obstructive uropathy is a catch-all term encompassing any cause of complete or partial, congenital or acquired, and permanent or intermittent obstruction of the urinary tract. Depending on the severity of obstruction and extent, it may result in permanent change in both the collecting system ...

Tumors of the male urethra

Tumors of the male urethra are uncommon. They can be categorized both on the grounds of histology and location. Histology squamous cell carcinoma of the urethra: 80% urothelial/transitional cell carcinoma of the urethra: 15% (predominantly posterior urethra) adenocarcinoma of the urethra: 5%...

Scrotal infections

The scrotum and its content are subject to a number of infective processes including: scrotal cellulitis scrotal abscess Fournier gangrene epididymitis epididymo-orchitis orchitis testicular abscess scrotal filariasis

Urinary bladder wall or lumen calcification (differential)

Causes of urinary bladder wall or lumen calcification include: Common bladder calculus schistosomiasis of the urinary tract tuberculosis Uncommon neuroblastoma; pheochromocytoma radiation reaction alkaptonuria (ochronosis) amyloidosis calculus in a urachal cyst or in a bladder divertic...

Bilateral adrenal gland enlargement

The differential for bilaterally enlarged adrenal glands (adrenomegaly) is relatively limited: adrenal hyperplasia micronodular adrenal hyperplasia macronodular adrenal hyperplasia adrenocorticotropin (ACTH)-independent macronodular adrenocortical hyperplasia (AIMAH) 2 adrenal metastases a...

Risk factors for testicular germ cell tumors

Risk factors for testicular germ cell tumors (GCT) include: Caucasians at higher risk than African Americans (9:1) undescended testis 10-40x increased risk around 10% of all tumors are associated with undescended testis higher risk if intra-abdominal testis compared with intrainguinal orc...

Cortical nephrocalcinosis

Renal cortical nephrocalcinosis is ~20 times less common than medullary nephrocalcinosis. Pathology Etiology renal cortical necrosis: common 2 renal infarction/ischemia sepsis toxemia of pregnancy drugs snake bites arsenic poisoning extracorporeal shock wave lithotripsy (ESWL) hemolyt...

Medullary nephrocalcinosis

Renal medullary nephrocalcinosis is the commonest form of nephrocalcinosis and refers to the deposition of calcium salts in the medulla of the kidney. Due to the concentrating effects of the loops of Henle, and the biochemical milieu of the medulla, compared to the cortex, it is 20 times more co...

Echogenic renal pyramids (differential)

Echogenic renal pyramids in children can be due to many different causes. Differential diagnosis Nephrocalcinosis Iatrogenic (most common cause) furosemide (frusemide) vitamin D steroids Non-iatrogenic idiopathic hypercalcemia Williams syndrome hyperparathyroidism milk-alkali syndrom...

Urinary bladder diverticula (causes)

There are numerous causes of urinary bladder diverticula: Primary (congenital or idiopathic) Hutch diverticulum (in paraureteral region) Secondary bladder outlet obstruction bladder neck stenosis neurogenic bladder posterior urethral valve prostatic enlargement (hypertrophy; carcinoma) ...

Pyelonephritis

Pyelonephritis (plural: pyelonephritides) refers to an upper urinary (renal) tract infection with associated renal pelvis, renal calyceal and renal parenchymal inflammation, and comprises a heterogeneous group of conditions. bacterial pyelonephritis chronic pyelonephritis renal tuberculosis ...

Renal pseudotumor

A renal pseudotumor is a mass that will simulate a tumor on imaging but is composed of non-neoplastic tissue. There are many examples 1: Developmental prominent column of Bertin persistent fetal lobulation dromedary hump splenorenal fusion cross-fused renal ectopia renal hilar lip Infect...

Paratesticular tumors

A paratesticular mass may derive from a number of structures that surround the testis within the scrotum; most commonly, they derive from the spermatic cord. Pathology The masses can be categorized as benign (70%) or malignant (30%). Etiology Benign spermatic cord lipoma (most common parat...

Prostate cystic disease

Prostate cystic disease encompasses a wide variety of pathologies that all result in cyst formation within the prostate. Epidemiology Prostatic cysts are common, and ~5-8% men will develop one 4,7. However they are much more common in patients being investigated for infertility, with one study...

Chronic primary adrenal insufficiency

Chronic primary adrenal insufficiency has a number of causes. Primary adrenal insufficiency is termed Addison disease. Pathology Causes idiopathic atrophy: autoimmune adrenalitis 1 tuberculosis 1: 25% calcify fungal disease 1 histioplasmosis blastomycosis coccidioidomycosis AIDS 1 sarc...

Testicular cancer

Testicular cancers are the most common malignancy in men between the ages of 20 and 34 years. Epidemiology Testicular cancer is uncommon, accounting for less than 1% of all internal organ malignancies 2. The commonest histology of the tumor varies with the age of affected individuals. Over 90...

Testicular cystic lesions

Testicular cystic lesions are a relatively common occurrence on testicular ultrasound. They result from widely variable pathological entities ranging from benign to malignant. These entities include: simple testicular cyst tunica albuginea cyst (mesothelial cyst) cystic transformation of rete...

HIV associated neoplasms

HIV-associated neoplasms are numerous and can be broadly divided into two groups: AIDS-defining malignancies associated but not AIDS defining malignancies AIDS-defining malignancies The development of these malignancies in HIV affected individuals generally implies progression to AIDS 4: Ka...

Multiple filling defects of the ureter (differential)

Multiple filling defects within a ureter, as seen on conventional IVU or CT IVU, have a relatively small differential including: spreading or multifocal transitional cell carcinoma (TCC) vascular indentations multiple ureteral stones (steinstrasse) blood clots ureteritis cystica Stevens-Jo...

Paratesticular lesions

Paratesticular lesions have a long list of differential diagnoses: neoplastic benign epididymal cyst (most common epididymal mass) scrotal tunica cysts tunica vaginalis cyst tunica albuginea cyst spermatic cord lipoma scrotal hemangioma: is often hypervascular on color Doppler, unlike ot...

Epididymal calcification

Epididymal calcification can be seen on ultrasound as hyperechoic foci within the epididymal head. If the calcifications are large enough, then they may demonstrate acoustic shadowing. Differential diagnosis chronic epididymitis, e.g. bacterial, granulomatous (TB) or genital filariasis traum...

Prostate peripheral zone T2 hypointensity

Prostate peripheral zone T2 hypointensity is a common finding in pelvic MRIs that needs to be evaluated. A prostate MRI is usually performed with a multiparametric technique (mpMRI) to differentiate prostate cancer from more benign pathologies. mpMRI includes T2 weighted images, dynamic contrast...

Adrenal calcification

Adrenal calcification is not a rare finding in healthy asymptomatic people and is usually the result of previous hemorrhage or tuberculosis. Addison disease patients only occasionally develop calcification. Pathology Etiology Hemorrhage sepsis: Waterhouse-Friderichsen syndrome blunt abdomi...

Extratesticular cystic lesions (differential)

The differential diagnosis for extratesticular cystic lesions includes: hydrocele epididymal cyst spermatocele hematoma hematocele loop of bowel from an inguinal hernia abscess pyocele post-vasectomy varicocele Very rarely, a scrotal mesothelioma may present as a cystic mass.

Bilateral testicular lesions

Bilateral testicular lesions have a relatively limited differential diagnosis. Differential diagnosis Neoplastic lymphoblastic leukemia (acute or chronic) lymphoma (non-Hodgkin's) primary testicular lymphoma is rare but the testes are often the site of lymphoma/leukemia recurrence due to ...

Unilateral testicular lesions

The differential diagnosis for unilateral testicular lesions is wide-ranging. Neoplastic Common seminoma (40-50% of testicular malignancies) non-seminomatous germ cell tumors: testicular teratoma testicular epidermoid (teratoma with ectodermal elements only) testicular choriocarcinoma t...

Hyperreninaemic hypertension (differential)

Hyperreninaemic hypertension may have many causes including: renal artery stenosis renal secreting tumor, e.g. renal cell carcinoma, reninoma renal compression: large renal mass, subcapsular hemorrhage (Page kidney)

Renal artery stenosis

Renal artery stenosis (RAS) (plural: stenoses) refers to a narrowing of a renal artery. When the process occurs slowly, it leads to secondary hypertension. Acute renal artery stenosis does not lead to hypersecretion of renin. Pathology When the stenosis occurs slowly, collateral vessels form a...

Pear-shaped bladder

Pear-shaped (or teardrop-shaped) bladder is one whose normal round or ovoid shape has been extrinsically compressed to resemble a pear. The pear may be inverted or upright, depending on how the excess pelvic tissue compresses the bladder. Pathology Etiology Causes of a pear-shaped bladder inc...

Pediatric renal tumors and masses

Pediatric renal tumors and masses are another group of diseases (just like cystic renal diseases in both the adult and child) that are bewildering in their number, nomenclature and overlapping findings. Commoner lesions Wilms tumor: common in older children 1-8 years old nephroblastomatosis: ...

Nephrocalcinosis

Nephrocalcinosis, previously known as Anderson-Carr kidney or Albright calcinosis, refers to the deposition of calcium salts in the parenchyma of the kidney. It is divided into several types, with differing etiologies, based on the distribution: medullary nephrocalcinosis: 95% cortical nephroc...

Gas in the urinary bladder

There are numerous causes of gas in the urinary bladder. In the hospital setting by far the most common is the recent placement of an indwelling urinary catheter. Other causes include 1: iatrogenic indwelling urinary catheter is by far the most common cause cystoscopy, etc. emphysematous cys...

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