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Ileal conduit

An ileal conduit (or "Bricker conduit") was one of the original types of urinary diversions, and it is still in use today. Pathology The conduit is most often placed after cystectomy (or cystoprostatectomy) for muscle-invasive bladder cancer. Although not a continent diversion, it may be prefe...

Hematuria (pediatric)

Hematuria in a child is evaluated differently than in an adult in two main respects: there is a lower likelihood of a malignancy (renal or bladder) causing the hematuria preference is given to nonionizing radiation Pathology Hematuria can be considered in three main forms: "gross" hematuria...

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...

Hematuria (adult)

Hematuria occurs when blood enters the urinary collecting system and is excreted in the urine. There are many etiologies for hematuria, and they range from benign and transient to gravely concerning. Hematuria can derive from the kidneys, ureters, bladder, prostate (in men), or urethra. Imaging ...

Boari bladder flap

A Boari bladder flap is one of the options for ureteric reimplantation when the diseased ureteric segment is long (e.g. more than 5 cm). It is useful in the management of lower ureteric strictures and can be performed as either an open or laparoscopic procedure. It involves tubularisation of a f...

Scleroderma (renal manifestations)

Renal manifestations of scleroderma are common, affecting up to 25% of patients. Some patients (5-10%) can present with a scleroderma renal crisis (SRC). These patients have an abrupt onset of hypertension and acute renal failure 4. For a general discussion of scleroderma, please refer to the ...

Papillary cystadenoma of the epididymis

Papillary cystadenomas of the epididymis are the second most common benign tumors of the epididymis after adenomatoid tumors and are common in patients with von Hippel-Lindau disease (vHL). Clinical presentation Papillary cystadenomas are usually asymptomatic. Epidemiology They are more comm...

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...

Fraley syndrome

Fraley syndrome is the eponymous term for a dilated calyx (hydrocalyx) due to compression of a calyceal infundibulum from an adjacent artery or vein. Epidemiology It is a rare cause of obstruction of the collecting system. Involvement of an upper pole calyx is more common with the right side k...

Christmas inspired signs

There are many signs in radiology that are related to Christmas: snowcap sign in avascular necrosis snowman sign in total anomalous pulmonary venous return in pituitary macroadenomas snowstorm appearance in complete hydatidiform and testicular microlithiasis holly leaf sign in calcified pl...

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 ...

Mumps

Mumps is a (usually) self-limited viral infection that often occurs in epidemics among children. Its incidence has markedly diminished in countries with childhood vaccination programs, but may still be seen in adult patients who have not received vaccinations or who have waning immunity. It may ...

Loopogram

A loopogram is a fluoroscopic study of an ileal conduit. An ileal conduit is a type of urinary diversion. A loopogram is used to show the structure of the ileal conduit, ureters, renal pelvis, and renal calyces 2. Some authors defined loopogram as water-soluble contrast stomal enema that access...

Granulomatosis with polyangiitis (renal manifestations)

The renal manifestations of granulomatosis with polyangiitis (GPA) are occult on imaging, especially when compared to the pulmonary changes. For a general discussion of the condition, please refer to the main article on granulomatosis with polyangiitis (GPA). For other organ-specific radiograp...

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...

Abdominal radiography

Abdominal radiography can be useful in many settings. Before the advent of CT, it was a primary means of investigating gastrointestinal pathology and often allowed indirect evaluation of other abdominal viscera. Indications Although abdominal radiography has lower sensitivity and specificity t...

Normal genitourinary tract imaging examples

This article lists examples of normal imaging of the genitourinary tract and surrounding structures, divided by modality. Kidneys Plain radiograph KUB: example 1 abdominal x-ray: example 1 Intravenous Urogram (IVU) and Intravenous Pyelogram (IVP) IVU: example 1, example 2 Ultrasound rena...

CT kidneys, ureters and bladder (protocol)

Computed tomography of kidneys, ureters and bladder (CT KUB) is a quick non-invasive technique for diagnosis of urolithiasis. It is usually considered the initial imaging modality for suspected urolithiasis in an emergency setting 1. NB: This article is intended to outline some general principl...

End-stage renal disease

End-stage renal disease, also referred as end-stage renal failure or end-stage kidney disease, corresponds to the last stage of chronic kidney disease (stage 5), when the kidneys' function is no longer sufficient to sustain life (GFR <15 mL/min/1.73m2) and kidney replacement therapy (dialysis or...

Urethral calculus

Urethral calculi are an uncommon type of urolithiasis, accounting for ~1% of all urinary tract stones. Epidemiology They almost all occur in males 2 with two peak incidences - one in childhood and the other at 40 years 3. Clinical presentation Most commonly acute lower urinary tract symptoms...

Chronic kidney disease

Chronic kidney disease (CKD), also known as chronic renal failure, describes abnormal kidney structure or function, typically represented by a progressive loss of glomerular function. It is present when the glomerular filtration rate (GFR) is less than 60 ml/min/1.73 m2 for three consecutive mon...

Tubular ectasia of the epididymis

Tubular ectasia of the epididymis results in enlargement of the epididymis with multiple cystic interfaces. It typically occurs in those with a prior vasectomy but can be also seen with other causes of obstruction of the ductus deferens. Radiographic features Ultrasound characteristic "speckl...

Renal sympathetic denervation

Renal sympathetic denervation (RSDN), also known as renal denervation, is an interventional procedure that uses radiofrequency ablation to destroy the nerve endings in the wall of the renal arteries. Endovascular (trans-catheter) techniques are an alternative to surgical sympathectomy. Indicat...

Neonatal hydronephrosis

Neonatal hydronephrosis is most commonly diagnosed antenatally as fetal pylectasis, and in the majority of cases is due to pelviureteric junction (PUJ) obstruction. Pathology Etiology pelviureteric junction (PUJ) obstruction (50% of cases 1,6) vesicoureteric reflux (~20% of cases 5) poste...

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...

Chronic pyelonephritis

Chronic pyelonephritis is a form of pyelonephritis where there are longstanding sequelae of renal infection. At the time of writing there is still no definitive consensus as to whether the condition represents an active chronic infection, arises from multiple recurrent infections, or represents ...

Renal colic

Renal colic (also known as ureteric colic) refers to a pattern of abdominal pain most commonly caused by ureteric calculi. The pain (usually unilateral) is felt in the loin radiating down to the groin and is typically colicky (i.e. coming in waves) corresponding to peristalsis or spasm of the ur...

Perinephric stranding

Perinephric stranding refers to the appearance of edema within the fat of the perirenal space on CT or MRI. While a degree of symmetric bilateral perinephric stranding is common, particularly in the elderly, asymmetric or unilateral perinephric stranding is an important sign of renal inflammatio...

Ureteric calculi

Ureteric calculi or stones are those lying within the ureter, at any point from the ureteropelvic junction (UPJ) to the vesicoureteric junction (VUJ). They are the classic cause of renal colic-type abdominal pain. They are a subtype of the broader pathology of urolithiasis. Epidemiology The li...

Sperm cell granuloma

Sperm cell granulomas, also called epididymitis nodosa, are benign lesions that can occur in the scrotum; particularly, in those with a prior vasectomy. Epidemiology They occur after vasectomy in up to 40% of patients 2. Pathology It is considered a form of chronic epididymitis which occurs ...

Hemolytic uremic syndrome

Hemolytic uremic syndrome (HUS) is a multisystem thrombotic microangiopathic disease characterized by the triad of renal failure, hemolytic anemia and thrombocytopenia. It is the most common cause of renal failure in infancy and childhood requiring dialysis. There are two forms of this syndrom...

Medullary nephrocalcinosis (mnemonic)

A mnemonic used to remember the etiology of medullary nephrocalcinosis is: HAM HOP Mnemonic H: hyperparathyroidism A: (renal tubular) acidosis M: medullary sponge kidney H: hypercalcemia/hypercalciuria O: oxalosis P: papillary necrosis See also cortical nephrocalcinosis mnemonic renal...

Cortical nephrocalcinosis (mnemonic)

Mnemonics for common causes of cortical nephrocalcinosis are: COAG GOAT Mnemonics COAG C: cortical necrosis O: oxalosis A: Alport syndrome G: glomerulonephritis (chronic) GOAT G: glomerulonephritis (chronic) O: oxalosis A: Alport syndrome/ acute cortical necrosis T: transplant rejec...

Intratesticular hematoma

Intratesticular hematomas are hematomas within the testis and typically result from testicular trauma. Radiographic features Ultrasound isoechoic/hyperechoic region in the traumatised testis, becoming more hypoechoic as it resolves lack of color Doppler flow Differential diagnosis segmenta...

Segmental testicular infarction

Segmental testicular infarctions are uncommon testicular lesions that present with pain. They affect only a segment of the testis that is devascularised with normal remaining testicular parenchyma. Epidemiology Segmental testicular infarct is much uncommon compared to global testicular infarc...

Ureteric bud

The ureteric bud (also known as the metanephrogenic diverticulum) is a protrusion of the mesonephric duct that appears during the embryological development of urogenital organs. It will eventually form the urinary collecting system (i.e. collecting tubes, calyces, renal pelvis, ureter) of the ki...

Metanephric blastema

Metanephric blastema (or metanephrogenic blastema) is one of the two embryological structure that gives rise to the kidney, the other one being the ureteric bud. Related pathology Persistent metanephric blastemas after 36 weeks of gestational age are called nephrogenic rests. They are associat...

Adrenal washout

Adrenal washout can be calculated using the density value of an adrenal mass on non-enhanced, portal venous phase and 15 minutes delayed CT scans (density measured in Hounsfield units (HU)). It is primarily used to diagnose adrenal adenoma. absolute washout [(HUportal venous phase) - (HUdelaye...

Vesicovaginal reflux

Vesicovaginal reflux is a well-known entity rarely encountered by radiologists. It is a behavioral disorder, a type of dysfunctional elimination syndrome commonly encountered in pre-pubertal girls. It is defined as reflux of urine into the vaginal vault either in supine or upright position durin...

Leukemia (testicular manifestations)

Leukemia testicular manifestations, or testicular leukemia, can be seen in patients during and after acute leukemia. The blood-testis barrier limits chemotherapy from reaching the testis, and therefore the testis can act as a sanctuary for leukemic cells. typically presents with painless testic...

Spinning top urethra

Spinning top urethra is non-obstructive posterior urethral dilatation seen on voiding cystourethrography, mainly in females. It was initially considered as an indicator of distal urethral narrowing/stenosis. However, it is now believed to be due to functional discoordinate voiding or bladder ins...

Scrotal tunica cyst

Scrotal tunica cysts are paratesticular cystic lesions. They include: tunica vaginalis cysts tunica albuginea cysts Radiographic features Ultrasound Typically seen as a simple appearing paratesticular cystic lesion not in the region of the epididymis. See also paratesticular lesions

Scrotal cystocele

Scrotal cystoceles are a type of urinary bladder hernia, where the bladder herniates into the scrotum. Clinical presentation asymptomatic voiding problems scrotal swelling Radiographic features Ultrasound Scrotal sac will contain fluid. Emptying of a scrotal cystocele with voiding is an i...

Cloaca (urogenital)

The cloaca is the terminal portion of the hindgut. It is an embryonic structure (weeks 4-7) in which the distal ends of the gastrointestinal tract and urogenital system share a common channel. The most distal aspect of the cloaca is termed the cloacal membrane. The cloaca, or portions of it, ca...

Spermatic cord leiomyosarcoma

Spermatic cord leiomyosarcomas are uncommon malignant paratesticular masses. Epidemiology Accounts for ~10% of spermatic cord sarcomas. The average of a patient at presentation is 58 years old (although has been seen as young as 15 years old). Clinical features Patients may have left inguina...

Double retroaortic left renal vein

Double retroaortic left renal vein is a very rare entity that is usually clinically silent and detected incidentally at imaging, surgery, or autopsy. The knowledge of anatomical variations helps the surgeon or interventionist to avoid complications during surgery and interventional procedures 4...

Emphysematous epididymo-orchitis

Emphysematous epididymo-orchitis is a rare gas-forming epididymo-orchitis. The pathology of this condition is unknown. The diagnosis is usually made by ultrasonography with CT as an adjunct, to confirm the diagnosis, evaluate its extent and to rule out a coexistent retroperitoneal infective focu...

Ejaculatory duct cyst

Ejaculatory duct cysts are a rare type of cyst of the prostate gland. Pathology They occur due to obstruction of the ejaculatory duct which in turn can either be congenital or secondary (e.g. inflammation). They are usually intraprostatic when small but may extend cephalad when large. Radiog...

Imperforate hymen

Imperforate hymen is a congenital condition in which the hymen lacks a normal opening. Epidemiology It happens in 0.1% of the female population, usually an isolated finding. Clinical presentation Primary amenorrhea with cyclic lower abdominal pain during menarche age. An imperforate hymen c...

Gonadoblastoma

Gonadoblastomas are uncommon sex cord / stromal tumors. They are associated with disorders of sexual development (previously known as "intersex disorders"). Epidemiology The vast majority are found <30 years of age. Most are discovered in the perinatal period. May occur in phenotypic males or ...

Sertoli cell tumor of the testis

Sertoli cell tumors of the testis are uncommon sex cord stromal tumors. They are less common than Leydig cell tumors of the testis. Epidemiology May present in both pediatric and adult males, depending on the histologic subtype. Clinical presentation Testicular mass or firmness. May occasio...

Sex cord stromal tumors of the testis

Sex cord stromal tumors of the testis are uncommon testicular neoplasms. Although ~90% of these tumors are benign, they cannot be differentiated from testicular malignancies on imaging, and are therefore usually discovered after orchiectomy. Leydig cell tumor of the testis (most common, ~30% ho...

Abdominal and pelvic anatomy

Abdominal and pelvic anatomy encompasses the anatomy of all structures of the abdominal and pelvic cavities. This anatomy section promotes the use of the Terminologia Anatomica, the international standard of anatomical nomenclature.

Splenogonadal fusion

Splenogonadal fusion is a rare anomaly that occurs when there is congenital fusion between a portion of the spleen and a gonad or other mesonephric derivative. Epidemiology Much more common in male patients (~95%), occurs most commonly on the left (98%) and usually involve the testis (95%). Ha...

Non-medical drug use (radiological manifestations)

Radiological manifestations of non-medical drug use are not infrequently seen as the non-medical use of drugs is widespread. Epidemiology Interestingly, 2013 reports have suggested a decreasing incidence of reported drug use in the general population over the past decade, but it remains that ~...

Cystadenocarcinoma of the rete testis

Cystadenocarcinoma of the rete testis is the malignant version of cystadenoma of the rete testis. Epidemiology Primarily a disease of older men (>60 years old), but has been noted in a wide age range (8-91 years). Pathology Histologic evaluation requires exclusion of malignant mesothelioma...

Cystadenoma of the rete testis

Cystadenoma of the rete testis is a rare cystic testicular tumor. It does not have specific imaging features, but may be suggested in the differential of a large multiloculated cystic tumor involving the testis. It cannot be radiologically differentiated from cystadenocarcinoma. Epidemiology R...

Testicular and scrotal ultrasound

Testicular and scrotal ultrasound is the primary modality for imaging most of the male reproductive system. It is relatively quick, relatively inexpensive, can be correlated quickly with the patient's signs and symptoms, and, most importantly, does not employ ionizing radiation. MRI is occasion...

Intrarenal reflux

Intrarenal reflux (IRR) involves intrarenal extension of vesicoureteral reflux (VUR) into the tubular system of the kidney. IRR occurs in 3-10% of cases and can lead to renal injury, which may eventually result in renal scarring. The condition can be diagnosed by micturating cystourethrography ...

Burned-out testis tumor

Burned-out testis tumors may be present if there is metastatic retroperitoneal lymphadenopathy, but the primary testicular tumor is a relatively occult, scarred intratesticular focus. Approximately 50% of the "burned-out" tumors continue to harbor malignant cells. Pathology Retroperitoneal ger...

Testicular lymphoma

Testicular lymphoma is an uncommon testicular malignancy. Lymphoma can involve the testes in three ways: primary site of extranodal disease (primary testicular lymphoma) secondary involvement of systemic disease primary manifestation of subclinical systemic disease This article is concerned ...

Lentiform fork sign (basal ganglia)

The lentiform fork sign has been described on MRI and is seen as bilateral symmetrical hyperintensities in the basal ganglia surrounded by a hyperintense rim delineating the lentiform nucleus. It has been postulated to result from metabolic acidosis due to any cause 1, e.g. end stage renal dise...

Sarcomatoid renal cell carcinoma

Sarcomatoid renal cell carcinomas (sRCC) may develop when one of the more common histologic subtypes of renal cell carcinoma degenerates into a sarcoma. On imaging, they are generally large masses, with irregular contours, and malignant-appearing, but do not have specific imaging features. Epi...

Leydig cell tumor of the testis

A Leydig cell tumor of the testis is an uncommon testicular neoplasm. Its imaging appearance on ultrasound and MRI is nonspecific, but clinically it is associated with serum hormonal imbalance. Epidemiology 1-3% of all testicular tumors, but the most common sex-cord stromal tumor. Tend to be b...

Priapism

Priapism (rarely penile priapism, to differentiate from the very rare clitoral priapism) is a prolonged erection that persists beyond or is not related to sexual stimulation. Imaging, particularly Doppler ultrasound, can help distinguish between ischemic (low-flow) priapism, which is a urologic ...

Levator ani muscle

The levator ani muscle, also known as the muscular pelvic diaphragm, is the musculotendinous sheet that forms the majority of the pelvic floor, supports the pelvic viscera, and aids in urinary and fecal evacuation as well as maintaining continence. Gross anatomy The levator ani has three main ...

Urinary bladder wall thickening

Urinary bladder wall thickening is a common finding and its significance depends on whether the bladder is adequately distended. Radiographic features Ultrasound In both adults and children, the wall may be considered thickened on ultrasound if it measures 6: >3 mm when distended (>25% expec...

Renal cyst

Renal cyst is a generic term commonly used in description of any predominantly cystic renal lesion. The majority of parenchymal cystic lesions represent benign epithelial cysts; however, malignancy such as renal cell carcinoma may also present as a cystic lesion 8. Renal cysts are usually evalu...

Papillary renal cell carcinoma

Papillary renal cell carcinomas (pRCC) are the second most common histological subtype of renal cell carcinoma (RCC). Epidemiology This subtype may account 13-20% of all renal cell cancer 1. This subtype is also the most common in the renal transplant population 11. There is slightly increased...

Goldman classification of urethral injuries

The Goldman classification of urethral injuries is a more widely accepted classification than one proposed by the American Association for the Surgery of Trauma (AAST). The Goldman classification is based on the anatomical location of the urethral injury and was initially proposed by Colapinto a...

Fibrous pseudotumor of the scrotum

Fibrous pseudotumor of the scrotum is a relatively rare, non-neoplastic extratesticular non-epididymal lesion. Epidemiology It affects any age. Although rare, it is considered the third most common extra testicular mass after a scrotal lipoma and an epididymal adenomatoid tumor. Risk factors...

Urethral injury

Urethral injuries can result in long-term morbidity and most commonly result from trauma. The male urethra is much more commonly injured than the female urethra and is the focus of this article. Clinical presentation In the setting of trauma, the classic triad of blood of the external urethral...

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 ...

Renal milk of calcium cysts

Renal milk of calcium cysts refer to the appearance of a calcium precipitate found either within a calyceal diverticulum, that has lost communication with the collecting system, or within a simple renal cyst. Clinical presentation Renal milk of calcium cysts are typically asymptomatic. Radi...

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...

Adrenal lymphangioma

Adrenal lymphangiomas, also known as cystic adrenal lymphangiomas, are rare, benign cystic adrenal lesions. Epidemiology Adrenal lymphangiomas are extremely rare; prevalence is estimated at 0.06% 8. They can occur at any age, with a peak incidence between the 3rd and 6th decades of life. Accor...

Adrenal vein sampling

Adrenal vein sampling (AVS) is a procedure where blood is collected from the adrenal veins via catheter to confirm autonomous hormone production, if it is unilateral or bilateral, and to guide further treatment 1. If unilateral, the adrenal gland can be removed by surgery; thus curing secondary ...

Congenital adrenal hyperplasia

Congenital adrenal hyperplasia, previously known as adrenogenital syndrome, is a group of seven autosomal recessive disorders relating to an enzyme deficiency affecting adrenal steroidogenesis. Epidemiology The incidence is highly variable depending on the enzyme deficiency ranging from 1 in 2...

Hypovitaminosis A

Hypovitaminosis A results from inadequate intake of vitamin A, fat malabsorption, or liver disorders and produces a variety of epithelial alterations. Epidemiology The World Health Organizatiοn currently estimates that 45-122 countries have a vitamin A deficiency of public health significance ...

Prostatic artery embolization

Prostatic artery embolization (PAE) is a minimally invasive procedure utilized to treat benign prostatic hyperplasia (BPH). Indications PAE has been used for controlling prostatic hemorrhage (such as that associated prostate cancer) since 1970. However, its use in the treatment of lower urina...

Testicular trauma

Testicular trauma is the third most-common cause of acute scrotal pain and may result in various degrees of damage to the testes. Pathology Testicular rupture and testicular ischemia/infarct are two severe complications which need to be ruled out. Other injuries that can occur include 1: test...

Zinner syndrome

Zinner syndrome is a triad of mesonephric (Wolffian) duct anomalies comprising unilateral renal agenesis, ipsilateral seminal vesicle cyst, and ejaculatory duct obstruction 1. Epidemiology The condition is rare, with approximately only 200 reported cases until 2009 9. Clinical presentation P...

Tunica vaginalis testis mesothelioma

Tunica vaginalis testis mesothelioma refers to mesothelioma arising from the tunica vaginalis. Epidemiology Malignant mesothelioma originating from the tunica vaginalis is extremely rare. Clinical presentation Patients usually present with enlarging or recurrent hydrocele, or less frequen...

Manta ray sign (bladder)

The manta ray sign is a radiographic appearance in bladder exstrophy. It describes wide midline separation of the pubic bones simulating the appearance of a manta ray swimming towards you 1. The sacrum and iliac wings recall the manta ray’s head and body, with the widely spaced pubic rami formin...

Aubergine sign (penis)

The aubergine sign (also known as egg-plant sign or deformity) is a clinical sign of a fractured penis. Hemorrhage beyond the tunica albuginea produces swelling and bruising of the penis simulating the appearance of an aubergine.

Tunica vaginalis cyst

Tunica vaginalis cyst is a type of benign paratesticular cystic lesion. It is a cyst that arises from the tunica vaginalis and, in conjunction with tunica albuginea cysts, they are collectively termed scrotal tunica cysts. Pathology Their exact cause is unknown, although history of trauma, hem...

Ureteric injury

Ureteric injury is a relatively uncommon, but severe event, which may result in serious complications as a diagnosis is often delayed. Clinical presentation Ureteric injuries unreliably demonstrate macro- or microscopic hematuria as it may be absent in up to 25% of patients 5, 6. Classic clin...

Adrenal collision tumor

An adrenal collision tumor or collision tumor of the adrenal gland is an uncommon condition where two histologically distinct tumors abut each other or are in close proximity in the same adrenal gland. Pathology Collision tumors have been reported in nearly every organ, for example, collision ...

White pyramid sign (kidney)

The white pyramid sign, also known as dense renal medulla sign (DRM) or hyperdense renal pyramids sign, refers to the CT appearance of the medullary pyramids of the kidney which can be seen normally on unenhanced CT scans as high-attenuation triangular structures. Pathology Etiology incidenta...

Molar tooth sign (abdomen)

The abdominal molar tooth sign refers to the appearance of contrast media which has spilled out of the urinary bladder on CT cystography after extraperitoneal bladder rupture. Contrast flows out of the ruptured bladder, occupying the preperitoneal cavum Retzii and surrounds the bladder in the s...

Schiller-Duval body (histology)

Schiller-Duval body is a perivascular structure that can be found in 50% of testicular yolk sac tumors also known as endodermal sinus tumors. If present it is considered pathognomonic. Pathology A central vessel is surrounded by tumor cells, and the cell-vessel complex is contained in a cysti...

Prostate Imaging-Reporting and Data System (PI-RADS)

PI-RADS (Prostate Imaging–Reporting and Data System) is a structured reporting scheme for multiparametric prostate MRI in the evaluation of suspected prostate cancer in treatment naive prostate glands. This article reflects version 2.1 (v2.1), published in 2019 and developed by an internationall...

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