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.

904 results found
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Goblet sign (ureter)

The goblet sign, also known as the champagne glass sign, refers to the appearance of the ureter when it is focally dilated by an intraluminal mass. It is best seen when the ureter is opacified by retrograde contrast (retrograde ureterogram). Presence of this sign indicates the pathology to be ch...
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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...
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Gonadal artery

The gonadal arteries are the paired primary vascular supply to the ovaries in the female and the testes in the male. As the anatomy of the gonadal arteries differs substantially between the sexes, they are covered separately: ovarian arteries testicular arteries
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Gonadal vein

The gonadal veins are paired structures that drain the gonads in males and females. In males it is called the testicular vein (or internal spermatic vein) and in females it is called the ovarian vein. The gonadal veins ascend with the gonadal arteries in the abdomen along the psoas muscle anteri...
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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 ...
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Granulomatosis with polyangiitis

Granulomatosis with polyangiitis (GPA), previously known as Wegener granulomatosis, is a multisystem necrotizing non-caseating granulomatous c-ANCA positive vasculitis affecting small to medium sized arteries, capillaries and veins, with a predilection for the respiratory system and kidneys 3. ...
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Granulomatosis with polyangiitis (renal manifestations)

The renal manifestations of granulomatosis with polyangiitis (GPA) (previously known as Wegener granulomatosis) are occult on imaging, especially when compared to the pulmonary changes. Approximately half of GPA patients have kidney disease at presentation. Granulomatosis with polyangiitis is a ...
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Granulomatous prostatitis

Granulomatous prostatitis is a nodular form of chronic prostatitis. It is usually diagnosed on biopsy. Pathology Causes idiopathic infection iatrogenic BCG post-radiotherapy systemic disease: sarcoidosis autoimmune Subtypes Several classification systems exist. A frequently used clas...
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Great vessel space

The great vessel space is the fourth retroperitoneal space along with the anterior and posterior pararenal spaces, and the perirenal space 1,2. Unlike other retroperitoneal spaces, it is not well-defined by fascial planes and thus disease processes affecting other retroperitoneal spaces can also...
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Growing teratoma syndrome

Growing teratoma syndrome is a rare complication after treatment for metastatic (or in the case of intracranial disease, primary) non-seminomatous germ cell tumors (NSGCT). It was first described in the pediatric population with treated germ cell neoplasms, and represents enlarging masses at th...
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Hematospermia

Hematospermia (less commonly hemospermia) refers to the presence of blood in semen or ejaculatory fluid. It is a symptom that can cause great anxiety in patients despite usually being of benign etiology. Pathology Etiology Benign urogenital infections including sexually transmitted disease, ...
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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 ...
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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...
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Haemodialysis vascular access

Haemodialysis vascular access is required in patients with end-stage renal failure. Usually, it is an upper limb vascular access on the non-dominant side. Central venous access and lower limb access (less frequent) are other options. Types of vascular access Native arteriovenous fistula (AVF)...
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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...
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Hemorrhage exclusion sign (prostate)

The hemorrhage exclusion sign can be a useful MRI finding following prostate biopsy. Pathology The normal prostate produces high concentrations of citrate, which among other properties, acts as an anticoagulant 1. As tumor cells are dysfunctional, they will produce lower levels of citrate than...
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Hairy kidney sign (Erdheim-Chester disease)

The hairy kidney sign refers to the soft tissue rind of perirenal infiltration seen on cross-sectional imaging studies in Erdheim-Chester disease, and is considered to be pathognomonic of this disease. The ‘‘hairy’’ description refers to the associated thickening of the bridging perirenal septa ...
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Height adjusted total kidney volume

Height adjusted total kidney volume (HtTKV) is used in patients with autosomal dominant polycystic kidney disease to predict the onset of renal insufficiency. There is strong evidence to indicate that baseline htTKV predicts, with good sensitivity and specificity, the development of renal insuff...
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Hepatorenal syndrome

Hepatorenal syndrome refers to a form of acute kidney injury caused by changes in renal blood flow regulation due to liver pathology 1. Although the syndrome occurs mainly in cirrhotic livers it has been reported in patients with acute fulminant liver failure as well 1. Epidemiology The incide...
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Hereditary angiopathy with nephropathy, aneurysms, and muscle cramps syndrome

Hereditary angiopathy with nephropathy, aneurysms, and muscle cramps (HANAC) syndrome is an autosomal dominant monogenic COL4A1-related disorder. Epidemiology The exact prevalence is unknown. Clinical presentation The cardinal features of HANAC syndrome are helpfully described in the name of...
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Hereditary breast and ovarian cancer syndrome

Hereditary breast and ovarian cancer (HBOC) syndrome is caused by a mutation to either BRCA1 or BRCA2 genes. These patients have an increased risk of breast cancer, ovarian cancer, pancreatic cancer and prostate cancer. However, these gene mutations are not the only cause of hereditary breast ca...
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Hereditary leiomyomatosis and renal cell carcinoma

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a recently identified autosomal dominant tumor susceptibility syndrome. Pathology It is characterized by: predisposition to benign cutaneous and uterine leiomyomas (fibroids, myomas) susceptibility to early-onset renal cell carcin...
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Hereditary renal cancer syndromes

Despite the vast majority of renal cancers being sporadic, there are a number of hereditary renal cancer syndromes: von Hippel Lindau syndrome: predominantly clear cell type tuberous sclerosis: predominantly clear cell type (also associated with angiomyolipoma) hereditary paraganglioma-pheoch...
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Herlyn-Werner-Wunderlich syndrome

Herlyn-Werner-Wunderlich (HWW) syndrome, is a rare anomaly characterized by Müllerian duct anomalies (MDA) associated with mesonephric duct anomalies 3. This entity is also known as obstructed hemivagina and ipsilateral renal anomaly (OHVIRA). It is not to be confused with the Wunderlich syndrom...
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Hermaphroditism

Hermaphroditism states are a result of abnormalities in embryonic development and may have mixed characteristics of each sex, with variable clinical manifestations. True hermaphroditism is defined as the simultaneous presence in a single individual of both testicular and ovarian tissues, that may...
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Hernia (general)

Hernias (or herniae) are a common pathological entity, in which an anatomical structure passes into an abnormal location via an opening. The opening may be a normal physiological aperture (e.g. hiatus hernia: stomach passes through the diaphragmatic esophageal hiatus) or pathological. Iatrogeni...
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Heterogeneous testicular echotexture

Heterogeneous testicular echotexture at ultrasound may be the result of a variety of underlying pathology: seminiferous tubular atrophy - can occur in around 14% of middle aged to elderly patients 2 testicular trauma orchitis
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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 ...
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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...
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HIV-associated nephropathy

HIV-associated nephropathy (HIVAN) is commonly seen in patients with HIV/AIDS and leads to end-stage renal disease (ESRD). The diagnosis is not imaging-based and must be confirmed by renal biopsy. Epidemiology HIVAN is seen in patients at advanced stages of HIV and AIDS, but it can also be see...
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Hockey stick sign (disambiguation)

The hockey stick sign can refer to a variety of different signs and appearances: hockey stick sign (thyroid hemiagenesis) hockey stick sign (Creutzfeldt-Jakob disease) hockey stick sign (ureters)
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Horseshoe adrenal gland

A horseshoe adrenal gland is a very rare anomaly. It is also sometimes referred to as a butterfly, fused or midline adrenal gland. It is a solitary adrenal gland that is present in the midline of the fused portion either passing between the aorta and the inferior vena cava or posterior to the a...
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Horseshoe kidney

Horseshoe kidneys are the most common type of renal fusion anomaly. They render the kidneys susceptible to trauma and are an independent risk factor for the development of renal calculi and transitional cell carcinoma of the renal pelvis. Epidemiology Horseshoe kidneys are found in approximate...
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Hurley stick ureters

Hurley stick ureters refers to the widening of the distal ureters with abnormal lateral and upward curvature instead of normal oblique intramural course in excretory urogram. The appearance of distal ureter resembles hurley stick used in the traditional Iris game of hurling. This is seen in blad...
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Hutch diverticulum

Hutch diverticula are congenital bladder diverticula, seen at the vesicoureteric junction, in the absence of posterior urethral valves or neurogenic bladder. They are thought to result from a weakness in the detrusor muscle anterolateral to the ureteral orifice. Epidemiology They occur almost...
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Hydrocele

Hydroceles are acquired or congenital serous fluid collections between the layers of the tunica vaginalis surrounding a testis or spermatic cord. They are the most common form of "testicular" enlargement and present with painless enlargement of the scrotum. On all modalities, hydroceles appear a...
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Hydrocele of the canal of Nuck

Hydrocele of the canal of Nuck is a rare condition in female children caused by a failure of complete obliteration of the canal of Nuck 1. The canal of Nuck is an abnormal patent pouch of peritoneum extending anterior to the round ligament of the uterus into the labia majora 2. Incomplete oblite...
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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...
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Hydronephrosis (grading)

Grading systems of hydronephrosis have been devised to communicate the degree of upper collecting system dilatation. The most common system used (Society of Fetal Ultrasound, SFU) was originally designed for grading neonatal and infant hydronephrosis: grade 0 no dilatation, calyceal walls are ...
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Hydroureter

Hydroureter refers to abnormal dilation (>3 mm) of the ureter and may occur in combination with hydronephrosis.  Terminology The term, megaureter, is usually reserved for ureters >7 mm in diameter. The term hydroureteronephrosis (or hydronephroureterosis) may be used when ureteric dilatation o...
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Hymen

The hymen (plural: hymens) is a thin fold of mucous membrane which extends across the vaginal opening, usually with some form of internal defect, which permits the free passage of normal menses.  It usually ruptures during coitus with the remnants, usually in the form of small tags of tissue ar...
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Hyperdense renal cyst

Benign hyperattenuating renal cysts are also known as hyperdense renal cysts. Epidemiology They are frequently found in patients with either acquired cystic renal disease or autosomal dominant polycystic renal disease 1. Radiographic features homogeneously hyperattenuating (even when a narro...
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Hyperparathyroidism

Hyperparathyroidism is the effect of excess parathyroid hormone in the body. It can be primary, secondary, or tertiary. There are many characteristic imaging features, predominantly involving the skeletal system. Pathology Increased levels of the parathyroid hormone lead to increased osteoclas...
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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)
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Hypertrophied column of Bertin

Columns of Bertin represent the extension of renal cortical tissue which separates the pyramids, and as such are normal structures. They become of radiographic importance when they are unusually enlarged and may be mistaken for a renal mass (renal pseudotumor). Nomenclature of such enlarged col...
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Hypogastric nerves

The hypogastric nerves are paired nerve bundles that are part of the autonomic nervous system and located in the pelvis.  Summary location: pelvis origin: contain sympathetic fibers descending from the superior hypogastric plexus and parasympathetic fibers ascending from the inferior hypogast...
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Hypospadias

Hypospadias refers to a type of congenital malformation affecting the male external genitalia. Epidemiology The estimated prevalence is ~2 (range 0.2-4.1) per 1000 live births. Pathology The urethral meatus is abnormally positioned proximally and ventrally to its normal position. It is thou...
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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 Organization currently estimates that 45-122 countries have a vitamin A deficiency of public health significance ...
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Idiopathic retroperitoneal fibrosis

Idiopathic retroperitoneal fibrosis, also known as Ormond disease, is a subtype of retroperitoneal fibrosis where no obvious cause is found. It includes a spectrum of diseases which are characterized by fibroinflammatory tissue encasing the abdominal aorta and the iliac arteries. This process ma...
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Idiopathic scrotal calcinosis

Idiopathic scrotal calcinosis, sometimes called dystrophic scrotal calcinosis, is a rare benign condition characterized by superficial calcifications within the skin of the scrotum of unclear etiology. The condition is primarily cosmetic but may recur following excision of the calcified bodies. ...
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IgA nephropathy

IgA nephropathy (also known as IgA nephritis or Berger disease) is a form of glomerulonephritis.  Epidemiology IgA nephropathy is considered the most common glomerulonephritis worldwide and is a leading cause of chronic kidney disease and renal failure. Pathology Primary IgA nephropathy is c...
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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...
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Ileal ureter interposition

Ileal ureter interpositions are uncommon urologic reconstructions, using a loop of small bowel to replace a damaged ureter. The concept is similar to the formation of a neobladder from small bowel (e.g. ileal conduit), except one is forming a neo-ureter. Variants include using colon as an inter...
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Ileovesicostomy

Ileovesicostomy (also known as "cutaneous ileocystostomy", "ileal chimney", or "bladder chimney") is an uncommon urologic diversion in which a loop of small bowel is anastomosed/augmented to the dome of the bladder. This loop of bowel then exits through a urostomy. The diversion is not continent...
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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...
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Incidentaloma

An incidentaloma is a radiological neologism to denote a lesion found incidentally and of dubious clinical significance. Although it can refer to any incidental lesion (e.g. pituitary 3, thyroid 4), it is most often used to denote an incidental adrenal lesion, which is commonly an adrenal adenom...
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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 ...
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Inferior adrenal artery

The inferior adrenal (suprarenal) artery is one of three adrenal arteries that supplies the adrenal gland. Gross anatomy Origin Ipsilateral renal artery (usually before the terminal division of the renal artery) Location The course of the inferior suprarenal artery depends on its origin. Re...
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Inferior hypogastric plexus

The inferior hypogastric plexuses are autonomic nerve plexuses located in the pelvis. Summary location: lies in pelvis in extraperitoneal connective tissue on pelvic sidewall anterolateral to the mesorectum origin: formed mainly from pelvic splanchnic branches (parasympathetic) and sacral spl...
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Inferior rectal nerve

The inferior rectal nerve, also known as the inferior anal nerve or inferior hemorrhoidal nerve, is a branch of the pudendal nerve which is derived from S2, S3 and S4 nerve roots of the sacral plexus. The nerve provides sensory innervation to the anal canal inferior to the pectinate line and mot...
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Infertility

Infertility is common, affecting 15-20% of couples, and is defined as the inability to conceive after one year of unprotected intercourse in the fertile phase of the menstrual cycle 3. It can be due to a variety of both female and male factors, and these are discussed in separate articles: fema...
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Inflammatory myofibroblastic tumor

Inflammatory myofibroblastic tumors (IMT), also known as plasma cell granulomas, are rare neoplasms that have a diverse spectrum of biological behavior.  Terminology These tumors were previously referred as inflammatory pseudotumor.   Epidemiology They can occur at any age and there is curre...
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Inguinal canal

The inguinal canal is a passage in the anterior abdominal wall that transmits structures from the pelvis to the perineum formed by the fetal migration of the gonad from the abdomen into the labioscrotal folds. Gross anatomy The inguinal canal has an oblique course, is 4 cm in length and has tw...
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Inguinal lymph nodes

The inguinal lymph nodes (often shortened to the inguinal nodes) are a major group of lymph nodes in the lymphatic system. They are the major drainage pathway of the lower limbs, genitals, dorsal perineum and the inferior most aspect of the anterior abdominal wall. The inguinal nodal group is s...
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Internal iliac lymph nodes

The internal iliac lymph nodes (often shortened to internal iliac nodes) are the lymph nodes found adjacent to the internal iliac artery and its branches and drain the regions supplied by these vessels. This encompasses a large area from the genitalia anteriorly, the psoas muscle posteriorly and...
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Internal pudendal vein

The internal pudendal veins are the set of accompanying veins to the internal pudendal artery draining the perineal region to empty into the internal iliac vein. Gross Anatomy Tributaries inferior rectal veins males penile bulb and scrotum vein females clitoris and posterior labial vein ...
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International prostate symptom score

The international prostate symptom score (IPSS) is an 8 question (7 symptom questions + 1 quality of life question) screening tool used in screening, diagnosis, symptom tracking and aiding management of the symptoms associated with bladder emptying and is useful in those with benign prostatic hy...
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International Society of Urological Pathology Vancouver classification of renal neoplasia

The International Society of Urological Pathology Vancouver classification of renal neoplasia is a now-outdated classification of renal tumors published in 2013. It formed the basis for the most recent revision of the WHO classification of tumors of the kidney, published in 2016. For reference, ...
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Interstitial cystitis

Interstitial cystitis (or painful bladder syndrome) refers to an inflammatory condition affecting the bladder. It is usually classified as urinary bladder pain and irritative symptoms of more than 6 months' duration. It usually represents a diagnosis of exclusion. Traditionally, it has been defi...
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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 ...
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Intramural fat of the urinary bladder

Intramural fat of the urinary bladder is an occasional benign finding on CT/MRI.  Epidemiology Incidence of this finding on histopathological studies is up to 4%. Published radiological and pathological cohorts both report a male predominance. Clinical presentation Incidental asymptomatic fi...
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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 ...
Article

Intratesticular hematoma

Intratesticular hematomas typically result from testicular trauma. Radiographic features isoechoic/hyperechoic region in the traumatised testicle, becoming more hypoechoic as it resolves lack of color Doppler flow Differential diagnosis segmental testicular infarct testicular neoplasm gra...
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Intratesticular varicocele

Intratesticular varicocele is a rare entity, occurring in ~2% of symptomatic population. Pathology It is defined as dilated intratesticular veins seen in relation to the mediastinum testis and extending peripherally. It is usually seen in the presence of ipsilateral extratesticular varicocele....
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Intrathoracic kidney

An intrathoracic kidney is a very rare form of ectopic kidney. There has been no reported increased incidence of stones or infections as can be seen with other forms of ectopic kidneys. The adrenal glands are usually normal in location. Clinical presentation Intrathoracic kidneys are usually a...
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Intravenous urography

Intravenous urography (IVU), also referred to as intravenous pyelography (IVP) or excretory urography (EU), is a radiographic study of the renal parenchyma, pelvicalyceal system, ureters and the urinary bladder. This exam has been largely replaced by CT urography.  Terminology Some prefer the ...
Article

Iron deficiency anemia

Iron deficiency anemia is a common cause of anemia and a common precipitant to radiological investigation. Epidemiology Amongst men and postmenopausal women, the incidence in the developed world is around 2%. Among premenopausal women, the incidence is greater and in most cases, investigation ...
Article

Ischiocavernosus muscle

The ischiocavernosus muscles are one of the three main muscles found in the superficial perineal pouch along with the bulbospongiosus and superficial transverse perineal muscles.  Summary origin: ischial tuberosity and ramus insertion: males: corpus cavernosum females: clitoris blood suppl...
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Isthmus (disambiguation)

Isthmus (plural isthmi) is an anatomical term and refers to a slender structure joining two larger components. Some of these uses of the word isthmus are now rarely used or only seen in older texts and articles: isthmus (aorta) isthmus (auditory tube) isthmus (auricle of the ear) isthmus (ci...
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Jackstone calculus

Jackstone calculus is the name assigned to the appearance of a subset of urinary calculi. Pathology Jackstone calculi are almost always composed of calcium oxalate dihydrate. They are nearly always created, and thus, located, in the bladder rather than the upper urinary tract. They are compos...
Article

Junctional parenchymal defect of kidney

Junctional parenchymal defects in renal imaging are a normal variant. Pathology It results from the incomplete embryonic fusion of renunculi. Radiographic features Ultrasound It can be seen as a triangular echogenic cortical defect, frequently seen in upper lobe parenchyma. The defect is th...
Article

Juxtaglomerular cell tumor

Juxtaglomerular cell tumors, also known as reninomas, are uncommon renal tumor of the juxtaglomerular cells. The tumor cells secrete renin and often cause severe hypertension and hypokalemia. Epidemiology Juxtaglomerular cell tumor affect all age groups, but are most common in adolescents and ...
Article

Kerr kink

The Kerr kink is a sign of renal tuberculosis. Scarring in the adjacent tissues due to chronic inflammation leads to a sharp kink at the pelviureteric junction (PUJ). History and etymology William "Bill" K Kerr, a Canadian urologist, described his eponymous sign in 1967 3.
Article

Ketamine bladder

Ketamine bladder or ketamine bladder syndrome refers to lower urinary tract symptoms associated with long-term ketamine use. Epidemiology The presence of lower urinary tract symptoms in long-term ketamine users has been identified to be as high as 90% in some studies 1. Clinical presentation ...
Article

Keyhole sign (posterior urethral valves)

The keyhole sign is an ultrasonographic sign seen in boys with posterior urethral valves. It refers to the appearance of the proximal urethra (which is dilated) and an associated thick-walled distended bladder which on ultrasound may resemble a keyhole.
Article

Kidneys

The kidneys are paired retroperitoneal organs that lie at the level of the T12 to L3 vertebral bodies. Gross anatomy Location The kidneys are located on the posterior abdominal wall, with one on either side of the vertebral column, in the perirenal space. The long axis of the kidney is parall...
Article

Kidney sweat sign

The kidney sweat sign refers to the presence of thin, hypoechoic, extracapsular fluid collections around kidneys in renal failure patients. This fluid is thought to represent perirenal edema. It can be appreciated on ultrasound, CT and MRI.  Differential diagnosis perirenal hematoma perirenal...
Article

Labeled imaging anatomy cases

This article lists a series of labeled imaging anatomy cases by system and modality. Brain CT head: non-contrast axial CT head: non-contrast coronal CT head: non-contrast sagittal CT head: angiogram axial CT head: angiogram coronal CT head: angiogram sagittal CT head: venogram axial CT ...
Article

Labia majora

The labia majora (singular: labium majus) form the anteroinferior most part of the vulva, they are continuous with the mons pubis anteriorly and the perineum posteriorly. The labia are apposed in the midline forming the, externally-visible, pudendal cleft.  Gross anatomy The labia majora have ...
Article

Labia minora

The labia minora (singular: labium minus) are small glabrous cutaneous folds lying between and just superior to the labia majora. At their posterior margin the labia may be conjoined by a thin cutaneous fold of skin, the frenulum of the labia (also known as the fourchette or posterior commissure...
Article

Lactate dehydrogenase

Lactate dehydrogenase (LDH or LD) is a key enzyme in most cells, catalyzing the reversible conversion of pyruvate to L-lactate. Its contemporaneous main clinical uses are limited primarily to the investigation of hemolysis, serous collections and as a tumor marker. Physiology L-lactate dehydro...
Article

Lacuna magna

Lacuna magna, also known as the sinus of Guérin, is a congenital blind-ended pouch located dorsal to navicular fossa of penis separated by fold and both share an external common opening to external urethral meatus. This diverticulum is located above and parallel to the urethra.  Epidemiology A...
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Lamellated

The term lamellated (or laminated which means the same thing) is a radiopathological term used to describe the layered appearance of many calculi, including those of the renal tract, the salivary glands, and the biliary tree. The internal structure of these calculi has been likened to that of an...

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