Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

818 results found
Article

Calyceal diverticulum

Calyceal diverticula, also known as pyelocalyceal diverticula are congenital outpouchings from the renal calyx or pelvis into the renal cortex. These diverticula are lined with transitional cell epithelium. Epidemiology Relatively uncommon, seen in 0.21% to 0.60% of intravenous urograms (IVU)....
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Calyceal microlithiasis

Calyceal microlithiasis or more specifically renal calyceal microlithiasis is defined as <3 mm hyperechoic foci noted within the renal calyces on gray scale ultrasonography 1. It has been considered as a precursor for renal stone formation.  Clinical presentation The patient may be asymptomati...
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Cannonball metastases (lungs)

Cannonball metastases refer to large, well circumscribed, round pulmonary metastases that appear, well, like cannonballs. The French term "envolée de ballons" which translates to "balloons release" is also used to describe this same appearance. Metastases with such an appearance are classically...
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Carcinogens

Carcinogens are substances known to cause cancer. They include: Brain vinyl chloride Nasopharynx / nasal passage nickel wood dust chromium Thyroid ionising radiation (not technically a substance) Skin arsenic coal tars polyaromatic hydrocarbons (PAH) Lungs arsenic asbestos chloro...
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Cardiorenal syndrome

Cardiorenal syndrome refers to an association between cardiac failure and renal failure. It can manifest as a new-onset of renal failure, or the aggravation of a pre-existing one within the ambit of an acute or chronic heart failure exacerbation. sometimes it can occur the other way around. Sub...
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Cervical cancer (staging)

Staging of cervical cancer can either be based on the TNM or FIGO system. Revised FIGO staging of cervical carcinoma 2009 8 stage 0: cervical intraepithelial neoplasia (HSIL or CIN III)  stage I: confined to cervix stage Ia: invasive carcinoma only diagnosed by microscopy. Ia1: stromal inva...
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Cervical intraepithelial neoplasia (staging)

Cervical intraepithelial neoplasia (CIN) (also known as cervical dysplasia) is the potentailly premalignant stage in the dysplastic changes in the squamous epithelium of the cervix.  Grading of CIN is based on the degree of dysplasia seen in a sample of cervical tissue: CIN I similar to condy...
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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...
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Chromaffin cells

Chromaffin cells are neuroendocrine cells found predominantly in the medulla of the adrenal gland. They are also found in other ganglia of the sympathetic nervous system and are derived from the embryonic neural crest. Embryology They arise in the fifth week of fetal development when neuroblas...
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Chronic kidney disease

Chronic kidney disease (CKD), also known as chronic renal failure, is a progressive loss of glomerular function caused by a long-standing renal parenchymal disease. It is present when the glomerular filtration rate (GFR) is less than 60 ml/min/1.73 m2 for three consecutive months or greater than...
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Chronic periaortitis

Chronic periaortitis is an inflammatory condition which typically involves the infrarenal portion of the abdominal aorta. It is a rare disease usually occurring in middle-aged men. It has various clinical presentations: idiopathic retroperitoneal fibrosis (IRF) perianeurysmal retroperitoneal ...
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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...
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Chronic prostatitis

Chronic prostatitis is a heterogeneous condition characterised by chronic inflammation of the prostate gland. Under the National Institutes of Health (NIH) classification system this may encompass chronic bacterial prostatitis chronic prostatitis and chronic pelvic pain syndrome (CPPS) Other...
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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 ...
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Chronic renal transplant rejection

Chronic renal transplant rejection is a form of renal transplant rejection. It usually later following transplantation. Pathology Chronic rejection is defined as a gradual deterioration in graft function beginning at least 3 months after transplantation 3.  The creatinine levels may rise but ...
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Chyluria

Chyluria is the finding of chyle in the urine, and is due to a pathological communication between the lymphatic system and the renal tract. It is most commonly found in South-Eastern Asia, where it is due to lymphatic filariasis, but in the non-tropical world it is most commonly encountered afte...
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Circumaortic left renal vein

Circumaortic left renal vein, also known as circumaortic renal collar is an anomaly of left renal vein when a supernumerary or accessory left renal vein passes posterior to the aorta, apart from the normal renal vein passing anterior to the aorta. This anomaly is potentially hazardous, if unreco...
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Circumcaval ureter

Circumcaval ureter, also known as retrocaval ureter, is a term used to describe an abnormal course of a ureter that encircles the inferior vena cava. Both of these terms are somewhat misleading, as this configuration is considered a developmental anomaly of the inferior vena cava (IVC). There ar...
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Citrate peak

Citrate is a compound examined in MR spectroscopy in the setting of possible prostate carcinoma. Citrate resonates at 2.6 ppm and is decreased in prostate cancer.  For more information go to: MR spectroscopy in prostate cancer
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Claw sign (mass)

The claw sign is useful in determining whether a mass arises from a solid structure or is located adjacent to it and distorts the outline. It refers to the sharp angles on either side of the mass, which the surrounding normal parenchyma forms when the mass has arisen from the parenchyma. As suc...
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Clear cell sarcoma of the kidney

Clear cell sarcomas of the kidney (CCSK) are a rare mesenchymal renal tumour that account for ~5% of primary renal neoplasms in the paediatric population 1.  Epidemiology Clear cell sarcoma of the kidney is the second most common primary malignant paediatric renal neoplasm after Wilms tumour, ...
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Cloacal exstrophy

Cloacal exstrophy (CE) is an extensive congenital abdominal wall defect which encompasses: exstrophy of the bladder omphalocoele lower abdominal wall defect Epidemiology The estimated prevalence is at around 1 in 50,000 to 200,000 live births. There is a recognised male predilection with a ...
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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...
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Cobb's collar

Cobb's collar (also known as a Moormann's ring or congenital narrowing of the bulbar uerthra) is a membranous stricture of the bulbar urethra just downstream of the external urethral sphincter. It is sometimes referred to as a type III posterior urethral valve, and does not maintain a connection...
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Cobra head sign (ureter)

The cobra head sign (or spring onion sign) refers to dilatation of the distal ureter, surrounded by a thin lucent line, which is seen in patients with an adult-type ureterocoele. The cobra head appearance indicates an uncomplicated ureterocele. The lucent "hood" of the cobra represents the comb...
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COL4A1-related disorders

COL4A1-related disorders are a group of autosomal dominant disorders caused by a mutation in the COL4A1 gene. Epidemiology The exact prevalence is unknown, but the group of disorders is considered to be under-recognised, especially asymptomatic variants 1. Clinical presentation The clinical ...
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Colovesical fistula

Colovesical fistulas are communications between the lumen of the colon and that of the bladder, either directly or via an intervening abscess cavity (foyer intermediaire). When the communication is between the rectum and urinary bladder, the term rectovesical fistula is used. Epidemiology The ...
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Congenital adrenal hyperplasia

Congenital adrenal hyperplasia (CAH) is a form of adrenal hyperplasia related to a variety of autosomal recessive disorders in adrenal steroidogenesis; characterized by low cortisol, low aldosterone and androgen excess.  Clinical presentation virilization/genital ambiguity of female fetuses (d...
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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 categorised as following: congenital valves  posterior urethral valve anterior urethral valv...
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Congenital megacalyces

Congenital megacalyces is an incidental finding which mimics hydronephrosis. It is a result of underdevelopment of the renal medullary pyramids with resultant enlargement of the calyces. It is more frequently seen in males. The enlarged, floppy calyces predispose to stasis, infection and calcul...
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Congenital megaureter

A congenital (primary) megaureter encompasses causes of an enlarged ureter which are intrinsic to the ureter, rather than as a result of a more distal abnormality; e.g. bladder, urethra (see secondary megaureter). It includes: obstructed primary megaureter refluxing primary megaureter althoug...
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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):...
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Congenital urachal anomalies

Congenital urachal anomalies are a spectrum of potential anomalies that can occur due to incomplete involution of the urachus. Epidemiology A urachal remnant occurs in approximately 1 in 5000 patients. Pathology The urachus connects the dome of the bladder to the umbilical cord during fetal ...
Article

Conjoint tendon

The conjoint tendon forms when the medial fibres of the internal oblique aponeurosis unite with the deeper fibres of the transversus abdominis aponeurosis. The conjoint tendon then turns inferiorly and attaches onto the pubic crest and pecten pubis 1. It forms part of the posterior wall of the i...
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Conn syndrome

Conn syndrome (or primary hyperaldosteronism) is a condition of excess of aldosterone production and occurs secondary to adrenal cortical adenoma, bilateral adrenal hyperplasia, or rarely, adrenal carcinoma. Differentiation between the causes is required to avoid unnecessary surgery.  Clinical ...
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Contrast-enhanced ultrasound

Contrast-enhanced ultrasound (CEUS) involves the administration of intravenous contrast agents containing microbubbles of perfluorocarbon or nitrogen gas. The bubbles greatly affect ultrasound backscatter and increase vascular contrast in a similar manner to intravenous contrast agents used in C...
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Contrast-induced nephropathy

Contrast-induced nephropathy (CIN) describes an association between intravenous or intraarterial contrast administration and renal impairment, but increasingly the evidence shows that contrast is not the cause of the renal impairment and that confounding factors such as sepsis are likely to be r...
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Cortical nephrocalcinosis

Renal cortical nephrocalcinosis is ~20 times less common than medullary nephrocalcinosis. Pathology Aetiology renal cortical necrosis: common 2 renal infarction/ischaemia sepsis toxaemia of pregnancy drugs snake bites arsenic poisoning extracorporeal shock wave lithotripsy (ESWL) haem...
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Cortical nephrocalcinosis (mnemonic)

A mnemonic for common causes of cortical nephrocalcinosis is: COAG Mnemonic C: cortical necrosis O: oxalosis A: Alport syndrome G: (chronic) glomerulonephritis See also nephrocalcinosis cortical nephrocalcinosis medullary nephrocalcinosis medullary nephrocalcinosis mnemonic
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Cortical rim sign

The cortical rim sign is useful in distinguishing acute pyelonephritis from a segmental renal infarct and is seen on contrast enhanced CT or MRI. In the setting of acute pyelonephritis, the areas of abnormally reduced enhancement typically involve a complete wedge of renal parenchyma, extending...
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Cowper duct syringocele

Cowper duct syringocele refers to a cystic dilatation of the main duct of the bulbourethral (Cowper) glands. Clinical presenation Affected patients may present with postvoid dribbling, urinary frequency, weak stream, or haematuria. Pathology Four groups of syringoceles have been described 2:...
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Cremasteric artery

The cremasteric artery is a small branch of the inferior epigastric artery that enters the deep inguinal ring of the inguinal canal and supplies the layers of the spermatic cord and also the skin of the scrotum, including the cremaster muscle. History and etymology The word "cremaster" derives...
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Cremaster muscle

The cremaster muscle is the thin fascial muscle of the spermatic cord made of skeletal muscle. It is also referred to as cremaster fascia or simply the cremaster. Its action is to retract the testes, important in thermoregulation and spermatogenesis.  Gross anatomy It is derived from the inter...
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Crossed fused renal ectopia

Crossed fused renal ectopia refers to an anomaly where the kidneys are fused and located on the same side of the midline. Epidemiology The estimated incidence is around 1 out of 1000 births 1. There is a recognised male predilection with a 2:1 male to female ratio. More than 90% of crossed ren...
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Crossed renal ectopia

Crossed renal ectopia is said to be present when the kidney is seen in the opposite retroperitoneal space. It is more common for the left kidney to be ectopically located on the right side. More than 85% of these get fused resulting in crossed fused renal ectopia. Less than 15% cases are non-fus...
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Cryptorchidism

Cryptorchidism refers to an absence of a testis (or testes) in the scrotal sac. It may refer to an undescended testis, ectopic testis, or an atrophic or absent testis. Correct localisation of the testes is essential because surgical management varies on location. Pathology The testes develop i...
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CT abdomen (summary)

This is a basic article for medical students and other non-radiologists CT abdomen is an increasingly common investigation that is used to help make diagnoses of a broad range of pathologies. A CT abdomen in its simplest form is a CT from diaphragm to symphysis pubis performed 60 seconds after ...
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CT cystography

CT cystography is a variation of the traditional fluoroscopic cystogram. Instead of anterograde opacification of the urinary collecting system (as with CT urography), contrast is instilled retrograde into the patient's bladder, and then the pelvis is imaged with CT. Indications suspected bladd...
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CT guided adrenal biopsy

CT guided adrenal biopsy is usually performed for the diagnosis of indeterminate adrenal nodules or tumours. This procedure has declined in recent years due to improvements in, and validation of, non-invasive CT and MR techniques that can now diagnose benign adrenal lesions with a high degree of...
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CT KUB

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. Advantages  quick easily accessible identification of calc...
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CT polytrauma (technique)

CT polytrauma/multitrauma, also called trauma CT, whole body CT (WBCT) or panscan, is an increasingly used investigation in patients with multiple injuries sustained after significant trauma. Clinical assessment and mechanism of injury may underestimate injury severity by 30% 8. There is some e...
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CT urography

CT urography (CTU or CT-IVU) has now largely replaced traditional IVU in imaging the genitourinary tract. It gives both anatomical and functional information, albeit with a relatively higher dose of radiation. The aim is to illustrate the collecting systems, ureters and bladder with intravenous...
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Curlicue ureter sign

The curlicue ureter sign1 is seen intravenous pyelogram in cases of ureteral herniation in sciatic hernia, causing a curled appearance of the herniated ureter. Although very rare, this sign is pathognomonic of sciatic hernia.
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Cushing syndrome

Cushing syndrome is due to the effects of excessive glucocorticoids which may be exogenous or endogenous. Terminology Cushing disease refers to glucocorticoid excess solely due to an adrenocorticotropic hormone-secreting pituitary adenoma, while Cushing syndrome encompasses all aetiologies of ...
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Cyst

A cyst is an abnormal fluid-filled structure which is lined by epithelium; with one exception: lung cysts contain gas, not fluid. By contradistinction, a pseudocyst lacks an epithelial lining and instead has a vascular and fibrotic capsule. Cysts are extremely common and found in most organs. E...
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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...
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Cystadenoma of the rete testis

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

Cystic adrenal neoplasms are uncommon and only account for a minority of cystic adrenal lesions 3. They may be represented several histological types: adrenal adenoma 1 adrenal cortical carcinoma 1,2 adrenal epithelioid angiosarcoma 2 phaeochromocytoma 1 teratoma (paediatric population) 4 ...
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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...
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Cystic lesions of the testes

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...
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Cystic renal diseases

Cystic renal disease can be confusing. There are many conditions, many of which have similar names or are eponymous, and with a few exceptions, are relatively rare. It is easiest to think of them into two separate demographic: paediatric cystic renal diseases adult cystic renal disease
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Cystic renal dysplasia

Cystic renal dysplasia refers to a group congenital renal anomalies characterised by the formation of cysts. Many of  the congenital cystic renal diseases  fall under this group. Pathology Associations Meckel-Gruber syndrome trisomy 13
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Cystic retroperitoneal lesions

A cystic retroperitoneal lesion can carry a relatively broad differenital which includes: retroperitoneal cystic lymphangioma retroperitoneal mucinous cystadenoma retroperitoneal cystic teratoma retroperitoenal cystic mesothelioma pseudomyxoma retroperitonei with cystic change perianal muc...
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Cystinuria

Cystinuria is an inherited condition in which there is an excess of cystine in the urine. This excess predisposes to the formation of cysteine stones. Terminology "Cysteine" refers to the amino acid. "Cystine" is the oxidized dimer of the amino acid. Epidemiology It is thought to occur in 1:...
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Cystitis cystica

Cystitis cystica is the same condition as ureteritis cystica and closely related to cystitis glandularis. It is a relatively common chronic reactive inflammatory disorders that occur in the setting of chronic irritation of the bladder mucosa. Epidemiology Cystitis cystica is seen in a variety ...
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Cystitis glandularis

Cystitis glandularis are small focal polypoid bladder mucosal thickenings and irregularities due to metaplasia of the urothelium (to mucin producing goblet cells) which proliferates into buds growing down into the lamina propria; this entity is closely related to cystitis cystica, with which it ...
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Cystocele

A cystocele, also known as a prolapsed bladder, is a form of pelvic organ prolapse where the bladder descends inferiorly and posteriorly into the vagina and perinuem. It may be accompanied by prolapse of other pelvic organs. Radiographic features CT / MRI  Sagittal images be particularly usef...
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Cystography

Cystography is a fluoroscopic study that images the bladder. It is similar to a voiding cystourethrogram (VCUG), and the difference between the studies is primarily one of emphasis; a cystogram focuses on the bladder and a VCUG focuses on the posterior urethra. The study has been adapted to CT w...
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Cystolithotomy

Cystolithotomy is a urologic procedure to remove one or more bladder stones. It is typically performed for a patient with large or numerous bladder stones or if an endoscopic approach has not been successful.  The traditional approach described below is an open cystolithotomy. Other approaches...
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Dartos muscle

The dartos muscle is the thin rugated fascial muscle of the scrotum made of smooth muscle. Hence it is also referred to as dartos fascia or simply the dartos. It forms from the subcutaneous tissue of the scrotum and base of the penis and attaches to the scrotal skin and fibrous midline septum be...
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Deep inguinal lymph nodes

The deep inguinal nodes are located within the femoral sheath, medial to the femoral vein. They receive afferent lymphatic drainage from the deep lymphatics of the distal lower extremity and perineum (e.g. glans penis / clitoris), and drain proximally into external iliac lymph nodes via channels...
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Deep perineal pouch

The deep perineal pouch is an anatomic space superior (deep) to the perineal membrane in the urogenital triangle of the perineum, anterior to the transverse line between the ischial tuberosities. Gross anatomy The deep perineal pouch is above (deep to) the perineal membrane in the urogenital t...
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Delayed nephrogram

A delayed nephrogram, commonly described on plain film urography, but also visible on CT urography, is when there is absence or reduction of the normal renal parenchymal enhancement on nephrographic phase images. A delayed nephrogram is characteristically unilateral and is usually distinguished...
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Detrusor muscle

The detrusor muscle (or detrusor urinae muscle)is the smooth muscle component of the urinary bladder and facilitates contraction of the bladder wall during micturition. Gross anatomy Forms the smooth muscle component of the bladder wall. The urothelial lining overlies it within the bladder cav...
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Developmental anomalies of the kidney and ureter

Developmental anomalies of the kidneys and ureters are numerous and not only potentially render image interpretation confusing but also, in many instances, make the kidneys more prone to pathology: number renal agenesis supernumerary kidney fusion horseshoe kidney: most common cross fused ...
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Diabetes insipidus

Diabetes insipidus (DI) is the deficiency or resistance to the hormone vasopressin (antidiuretic hormone), which results in polyuria and polydipsia.  Epidemiology DI occurs in 3 per 100,000 people 2.  Pathology DI may be described as 1-3: central/neurogenic/hypothalamic: vasopressin deficie...
Article

Dialysis disequilibrium syndrome

The dialysis disequilibrium syndrome (DDS) is a situation characterised by development of neurological symptoms caused by rapid removal of urea during hemodialysis. It develops primarily from an osmotic gradient that develops between the brain and the plasma as a result of rapid haemodialysis. I...
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Diverticulum

Diverticula are outpouchings of a hollow viscus and can be either true or false. Diverticulum is the singular form and diverticula is the correct Latin plural form. 'Diverticuli' and 'diverticulae' are erroneous and should not be used (cf. septum).  True diverticula contains all layers of the...
Article

Dorsal nerve of penis or clitoris

Dorsal nerve of penis or clitoris is one of the two terminal branches of the pudendal nerve that arises from nerve whilst in the pudendal canal. The other terminal branch is the perineal nerve.  Gross anatomy Course Entering the urogenital triangle of the perineum, the dorsal nerve of penis o...
Article

Double contrast cystography

Double contrast cystography (pneumocystography) is an older technique to evaluate the bladder lumen. It has rarely been used (if ever) after the advent of cross-sectional imaging. The exam is performed similarly to a conventional cystogram, but gas is also introduced through the Foley catheter....
Article

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 ...
Article

Drash syndrome

Drash syndrome, also known as the Denys-Drash syndrome, is associated with an abnormal WT1 gene (Wilms tumour gene) and consists of: Wilms tumour male pseudohermaphroditism progressive glomerulonephritis
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Dromedary hump

Dromedary humps are prominent focal bulges on the lateral border of the left kidney. They are normal variants of the renal contour, caused by the splenic impression onto the superolateral left kidney. Dromedary humps are important because they may mimic a renal mass, and as such is considered a...
Article

Drooping lily sign (ureter)

The drooping lily sign is a urographic sign in some patients with a duplicated collecting system. It refers to the inferolateral displacement of the opacified lower pole moiety due to an obstructed (and unopacified) upper pole moiety. The similarity to a lily is further strengthened by the smal...
Article

Drug-induced renal calculi

Drug-induced renal calculi are a subtype of renal calculi, whereby the stone formation is related to the patient's medication. Two main types of drug-induced calculi are described: medication-containing metabolically-induced Epidemiology Overall drug-induced urolithiasis accounts for 1-2% o...
Article

Ductus deferens

The ductus deferens (plural: ducti deferentia or deferentes) forms part of the male internal genitalia where it transports sperm from the epididymis to the ejaculatory duct. In modern anatomic nomenclature, it is no longer referred to as the vas deferens (plural: vasa deferentia or deferentes). ...
Article

Ductus deferens calcification

Calcification of the ductus deferens can result from: diabetes mellitus - most common normal ageing chronic infection - more frequently irregular; unlike diabetic calcification, inflammatory calcification tends to be unilateral and segmental 3 tuberculosis syphilis gonorrhoea schistosomia...
Article

Duplex collecting system

A duplex collecting system, or duplicated collecting system, is one of the most common congenital renal tract abnormalities. It is characterised by an incomplete fusion of upper and lower pole moieties resulting in a variety of complete or incomplete duplications of the collecting system. While ...
Article

Dynamic contrast enhancement in prostate cancer

Dynamic contrast enhancement (DCE) MRI is emerging as a useful clinical technique as part of a multiparametric approach for evaluating the extent of primary and recurrent prostate cancer.  Protocol and equipment Typically 3D T1-weighted fast spoiled gradient-echo MRI sequences with an endorect...
Article

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...
Article

Ectopic kidney

Ectopic kidney (or renal ectopia) is a developmental renal anomaly characterised by abnormal anatomical location of one or both of the kidneys. They can occur in several forms: cross fused renal ectopia ectopic thoracic kidney pelvic kidney Epidemiology The estimated incidence of an ectopi...
Article

Ectopic testis

Ectopic testes are a rare congenital anomaly, differing from undescended testis (cryptorchidism) in that ectopic testis is a congenitally abnormally located testis, that has descended from the abdominal cavity away from the normal path of descent while undescended testis are congenitally abnorma...
Article

Ectopic ureter

An ectopic ureter is a congenital renal anomaly that occurs as a result of abnormal caudal migration of the ureteral bud during its insertion to the urinary bladder. Normally the ureter drains via the internal ureteral orifice at the trigone of the urinary bladder.  In females, the most common ...

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