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 continuously improved upon by countless contributing members. Our dedicated editors oversee each edit for accuracy and style. Find out more about articles.
More than 200 results
Article
Ureteric jet
Ureteric jets, also known as ureteral jets, are the visualization of the normal physiological periodic efflux of urine from the distal end of each ureter into the bladder.
Pathology
When the urine passing down the ureter reaches the vesicoureteric junction (VUJ), it is forced out into the bla...
Article
Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD)
Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) represents a group of inflammatory demyelinating disorders united by the presence of IgG antibodies to myelin oligodendrocyte glycoprotein (MOG). MOGAD represents a distinct clinical entity that clinically overlaps but is n...
Article
McDonald diagnostic criteria for multiple sclerosis
McDonald diagnostic criteria for multiple sclerosis are clinical, radiographic, and laboratory criteria used in the diagnosis of multiple sclerosis. They were originally introduced in 2001 and revised multiple times (see "previous versions" below) most recently in 2017 5. A brief 2024 update is ...
Article
Thalassemia
Thalassemia is an autosomal recessive hemoglobinopathy first described in the Mediterranean region. The genetic defect causes a reduction in the rate of globin chain synthesis which causes the formation of abnormal hemoglobin molecules. The resultant microcytic anemia is the characteristic prese...
Article
Bronchogenic cyst
Bronchogenic cysts are congenital malformations of the bronchial tree (a type of bronchopulmonary foregut malformation). They can present as a mediastinal mass that may enlarge and cause local compression. It is also considered the commonest of foregut duplication cysts.
Epidemiology
Bronchoge...
Article
Extrarenal pelvis
Extrarenal pelvis refers to the presence of the renal pelvis outside the confines of the renal hilum; it is a normal anatomic variant.
Epidemiology
It is found in ~10% of the population 2.
Radiographic features
Ultrasound
An extrarenal pelvis usually appears dilated, erroneously suggesting...
Article
Tadpole sign
The tadpole sign, also known as the lollipop sign, refers to a characteristic morphology of post-traumatic bridging vein thrombosis with a rounded "head" and a tapering "tail". The question of whether this finding demonstrates a high specificity for abusive head trauma, a sub-type of non-accide...
Article
Ganglion cyst
Ganglion cysts are non-malignant cystic masses that occur in association with musculoskeletal structures. They are the most common soft tissue mass in the hand and wrist.
Terminology
Ganglion cysts are sometimes also simply referred to as ganglia or a ganglion, but should not be confused with...
Article
Zollinger-Ellison syndrome
Zollinger-Ellison syndrome (ZES) is a clinical syndrome that occurs secondary to elevated gastrin levels produced by a gastrinoma.
Clinical presentation
The syndrome presents with abdominal pain but can also present with diarrhea or other complaints as well. Diagnosis is often delayed by 5-7 ...
Article
Insulinoma
Insulinomas are the most common sporadic neuroendocrine tumor of the pancreas. On imaging, they usually present as small well-defined hypervascular tumors that may be found anywhere in the pancreas.
Epidemiology
Account for 40% of syndromic pancreatic endocrine tumors. The overall incidence i...
Article
Biparietal diameter
Biparietal diameter (BPD) is one of the basic biometric parameters used to assess fetal size.
BPD together with head circumference (HC), abdominal circumference (AC), and femur length (FL) are computed to produce an estimate of fetal weight. In the second trimester this may be extrapolated t...
Article
Gastrinoma
Gastrinomas are the second most common pancreatic endocrine tumor and the most common type in the setting of multiple endocrine neoplasia type I (MEN I).
Epidemiology
Most gastrinomas are sporadic, although some are seen in the setting of multiple endocrine neoplasia type I (MEN I). In general...
Article
Hamartoma
A hamartoma (plural: hamartomas or hamartomata) is a benign tumor-like malformation that consists of a collection of architecturally disorganized cells located in an area of the body where the cells are normally found. It is often due to abnormal development. Contrast this to a choristoma which ...
Article
Choristoma
A choristoma (plural: choristomas or less commonly choristomata) is simply a collection of microscopically normal cells or tissues in an abnormal location. Contrast this to a hamartoma which is derived only from local tissues.
Examples include:
adrenal choristoma (myelolipoma)
nasopharyngeal ...
Article
Goldenhar syndrome
Goldenhar syndrome, also known as oculo-auriculo-vertebral spectrum (OAVS), Goldenhar-Gorlin syndrome or facio-auriculo-vertebral dysplasia, is a complex congenital anomaly characterized by abnormalities of the ears, eyes and vertebrae.
Epidemiology
The estimated incidence is at 1 in 3000-5000...
Article
Bunionette
A bunionette, also known as a tailor's bunion, metatarsus quintus valgus, or digitus quintus varus, is a bony prominence at the lateral 5th metatarsal head. It is the lateral counterpart of the more common bunion of the first metatarsophalangeal joint, and when they occur together (often with sp...
Article
Vesicovaginal fistula
Vesicovaginal fistulas are abnormal fistulous connections between the urinary bladder and vagina, resulting in an involuntary discharge of urine through the vagina.
Epidemiology
The overall incidence of vesicovaginal fistula is unknown but was reported to be 2.11 per 100 births in Nigeria 1.
...
Article
Medical abbreviations and acronyms (R)
This article contains a list of commonly used medical abbreviations and acronyms that start with the letter R and may be encountered in medicine and radiology (please keep the main list and any sublists in alphabetic order).
A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R ...
Article
Medical abbreviations and acronyms (C)
This article contains a list of commonly used medical abbreviations and acronyms that start with the letter C and may be encountered in medicine and radiology (please keep both the main list and any sublists in alphabetic order).
A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q...
Article
Shy-Drager syndrome (historical)
The Shy-Drager syndrome is now recognized as a clinical manifestation of multiple systemic atrophy, no longer considered a separate entity.
Clinical presentation
The most striking clinical finding in Shy-Drager syndrome is arterial orthostatic hypotension. This remains a core clinical feature...