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.
16,879 results found
Article
Owl-eyes sign (spinal cord)
The owl-eyes sign, also known as snake-eyes sign or fried-eggs sign, represents bilaterally symmetric circular to ovoid foci of high T2-weighted signals in the anterior horn cells of the spinal cord and is seen on axial MR imaging. The sagittal corollary is a "pencil-like" vertical linear high T...
Article
Mastectomy
Mastectomy is a surgical treatment for breast cancer in which the entire breast tissue is removed through a surgical procedure as opposed to a wide local excision. Sometimes, adjacent structures, such as lymph nodes, are removed to prevent recurrence or metastasis. In some cases, mastectomy is d...
Article
Ligamentum teres hepatis (abdomen)
The ligamentum teres hepatis or round ligament is the fibrous cord formed by the obliterated fetal umbilical vein that runs in the free edge of the falciform ligament from the umbilicus into the left lobe of the liver.
Article
Falciform ligament sign
The falciform ligament sign, also called the Silver sign, is characterized by the falciform ligament being outlined with free abdominal gas in cases of pneumoperitoneum of a large amount.
It is almost never seen in isolation as, if there is enough free gas to outline the falciform ligament, th...
Article
Acute cholecystitis
Acute cholecystitis refers to the acute inflammation of the gallbladder. It is the primary complication of cholelithiasis and the most common cause of acute pain in the right upper quadrant (RUQ).
Epidemiology
Acute cholecystitis is a common cause of hospital admission and is responsible for a...
Article
Regenerative liver nodule
Regenerative liver nodules are a form of non-neoplastic nodules that arise in a cirrhotic liver.
Terminology
This may be slightly different from the term nodular regenerative hyperplasia, which are described histopathologically as regenerative nodules with little or no hepatic fibrosis and lar...
Article
Caudate nucleus
Caudate nuclei are paired nuclei which along with the globus pallidus and putamen are referred to as the corpus striatum, and collectively make up the basal ganglia. The caudate nuclei have both motor and behavioral functions, in particular maintaining body and limb posture, as well as controlli...
Article
Velum interpositum
The velum interpositum is a small membrane containing a potential space just above and anterior to the pineal gland which can become enlarged to form a cavum veli interpositi.
Gross anatomy
The velum interpositum is formed by an invagination of pia mater forming a triangular membrane the apex...
Article
Molar pregnancy
Molar pregnancies, also called hydatidiform moles, are one of the most common forms of gestational trophoblastic disease.
Epidemiology
Molar pregnancies are one of the common complications of gestation, estimated to occur in one of every 1000-2000 pregnancies 3. These moles can occur in a pre...
Article
Migraine
Migraines are a common primary headache disorder and can present variably. Typically they consist of debilitating headaches, accompanied by an aura in one-third of patients.
Epidemiology
Migraine is a very common condition, with a 1-year prevalence of 12% 8. It is most prevalent in early-middl...
Article
Cerebral hyperperfusion syndrome
Cerebral hyperperfusion syndrome is a rare complication seen after treatment of long-standing severe carotid stenosis by carotid endarterectomy or carotid artery stenting. It is believed to be the result of failure of normal cerebral blood flow autoregulation.
Terminology
Cerebral hyperperfus...
Article
Neer classification of proximal humeral fractures
The Neer classification of proximal humeral fractures is probably the most frequently used system along with the AO classification of proximal humeral fractures. The terminology and factors which influence the classification are essential for the utility of radiology reports of proximal humeral ...
Article
Neck-tongue syndrome
Neck-tongue syndrome is a rare syndrome characterized by altered sensation in one side of the tongue with ipsilateral neck pain triggered or aggravated by rotatory neck movement.
Epidemiology
Neck tongue syndrome is seen in a wide range of ages but is most commonly reported in older children,...
Article
Tongue
The tongue is a complex, principally muscular structure that extends from the oral cavity to the oropharynx. It has important roles in speech, swallowing and taste.
Gross anatomy
The tongue has a tip, dorsum, inferior surface and root. The tongue is made of a midline lingual septum and hyoglo...
Article
Sagittal balance
Sagittal balance, along with coronal balance, reflects the innate neutral standing position with C7 positioned over S1 as a feature of human bipedalism 1,3.
Pathology
Sagittal balance can change depending on various factors, including spinal deformities such as a loss of lumbar lordosis 1.
Ra...
Article
Choroidal fissure
The choroidal fissure, or choroid fissure, is a cleft of the medial surface of the cerebral hemisphere running immediately above the hippocampus and extends around the thalamus to the interventricular foramen of Monroe. It forms the medial wall of the lateral ventricle and attachment site for th...
Article
Medial posterior choroidal artery
The medial posterior choroidal artery is a small branch (often multiple - 40% of hemispheres) usually arising from the P2 segment of the PCA. It may also arise from one of the PCA branches, e.g. parieto-occiptal, calcarine, splenial artery.
It ascends deep to the rest of the PCA and supplies sm...
Article
Disarticulation
The term disarticulation refers to the disconnection of all or part of a limb from the body, specifically through a joint. This is in contrast to amputation, which is the disconnection or removal of the structure through a bone 1,2.
Article
Anterior corticospinal tract
The anterior corticospinal tract is formed at the level of the of the medullary pyramids, where the majority (90%) of descending corticospinal tract fibers decussate to form the lateral corticospinal tract. The remaining non-decussating fibers (10%) form the much smaller anterior corticospinal t...
Article
Rectal cancer response assessment
Assessment of rectal cancer response to therapy, which may be chemotherapy, radiotherapy, or a combination, relies on the synthesis of clinical, endoscopic and radiologic evaluation.
The purpose of neoadjuvant therapy is to downstage the tumor, to facilitate surgical resection, and reduce loca...