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Stener-like lesion of the medial collateral ligament of the knee

Stener-like lesions of the medial collateral ligament (MCL) occur when a tear involves the distal fibers of the superficial medial collateral ligament (sMCL) are displaced superﬁcially to the pes anserinus, which can result in compromised healing. Pathology Usually, the sMCL runs deep to the p...

Athelia

Athelia is a rare congenital condition characterized by the absence of the nipple. This may occur unilaterally or bilaterally. Associations Poland syndrome ectodermal dysplasia 2

Absent bow tie sign (knee)

The absent bow tie sign represents the loss of the normal appearance of the menisci on parasagittal MRI images and is suggestive of meniscal injury. Normally the medial and lateral menisci appear as low signal triangular structures linked by a thin body located between the femoral condyles and ...

Tulip bulb sign

The tulip bulb sign refers to the characteristic appearance of annuloaortic ectasia as seen on CT angiography. There is symmetric dilatation of the three sinuses of Valsalva, with extension into the ascending aorta and effacement of the sinotubular junction. It is seen especially in Marfan sy...

Vertebral body squaring (differential)

Vertebral body squaring refers to the loss of normal concavity of the anterior border of the vertebral body. It is seen in a variety of conditions, some of which are listed below. Differential diagnosis Ankylosing spondylitis Ankylosing spondylitis is the most common cause of vertebral body ...

Cogwheel sign

The cogwheel sign refers to the pelvic imaging appearance of dilated loops of fallopian tube seen in cross-section. It represents infolding projections (sometimes looking like nodules) into the fallopian tube lumen which are likened to that of a cogwheel. The sign is typically described on ultra...

Rolling stone sign

The rolling stone sign refers to the presence of gallstones within the gallbladder that are mobile when the patient moves. Small gallstones can sometimes be difficult to diagnose due to the absence of posterior shadow artefact but the presence of a rolling stone sign increases the confidence of...

Apple-peel intestinal atresia

Apple-peel intestinal atresia, also known as type IIIb or Christmas tree intestinal atresia, is a rare form of small bowel atresia in which the duodenum or proximal jejunum ends in a blind pouch and the distal small bowel wraps around its vascular supply in a spiral resembling an apple peel. Oft...

Double density sign (berry aneurysm)

Double density sign of berry aneurysms refers to the angiographic appearance of a small intracranial aneurysm projecting in front or behind a vessel of similar caliber. As such, the border of the aneurysm cannot easily be seen, but the extra contrast within it can be seen as a rounded area of in...

Nodule-in-nodule appearance (liver)

In hepatic imaging, a nodule-in-nodule appearance represents foci of abnormal arterial enhancement within a liver lesion, in cases of a liver regenerative nodule with a focus of hepatocellular carcinoma or high-grade dysplastic nodule. It is so called because of the nodular arterial enhancement ...

Cluster sign

The cluster sign is a finding on MRI and CT that is associated with pyogenic hepatic abscesses and can help differentiate pyogenic abscesses from other types of liver lesions. Radiographic features The cluster sign is best seen on MRI T2-weighted and postcontrast T1-weighted sequences. Small n...

Ballet sign (eyeball)

The ballet sign refers to the paralysis of voluntary movements of the eyeball with preservation of the automatic movements. Sometimes this sign is present with exophthalmic goiter and hysteria.

Double density sign (left atrium)

The double-density sign, also known as the double right heart border, is seen on frontal chest radiographs in the presence of left atrial enlargement, and occurs when the right side of the left atrium extends behind the right cardiac shadow, indenting the adjacent lung and forming its own distin...

Lateral femoral notch sign (knee)

The (deep) lateral femoral notch sign describes a depression on the lateral femoral condyle at the terminal sulcus, a junction between the weight-bearing tibial articular surface and the patellar articular surface of the femoral condyle. It is occasionally referred to as a deep sulcus sign, not ...

Callosal angle

The callosal angle has been proposed as a useful marker of patients with idiopathic normal pressure hydrocephalus (iNPH), helpful in distinguishing these patients from those with ex-vacuo ventriculomegaly (see hydrocephalus versus atrophy). It should be noted that there is nothing magical abou...

Scaphoid abdomen

Scaphoid abdomen is the term given to an inward concavity of the anterior abdominal wall. It is used both for the clinical appearance and its radiological equivalent. In children it maybe a sign of congenital diaphragmatic hernia. In both adult and pediatric patients, it raises the possibility...

Caput medusae sign - portal hypertension

The caput medusae sign is seen in patients with severe portal hypertension. It describes the appearance of distended and engorged paraumbilical veins, which are seen radiating from the umbilicus across the abdomen to join the systemic veins. History and etymology Caput is the Latin for head, ...

Unfolded aorta

The term unfolded aorta refers to the widened and decreased curvature of the aortic arch on a frontal chest radiograph giving an ‘opened up’ appearance. It is one of the more common causes of apparent mediastinal widening and is seen with increasing age, usually associated with aortic calcificat...

Teardrop (disambiguation)

A teardrop or teardrop sign is used in several regions of the body: extension teardrop fracture of the cervical spine flexion teardrop fracture of the cervical spine pelvic teardrop teardrop sign (ankle) teardrop sign (inferior orbital wall fracture) teardrop sign (intracapsular breast imp...

Cyclops lesion (knee)

The cyclops lesion, also known as localized anterior arthrofibrosis, is a painful anterior knee mass associated with loss of extension that arises as a complication of anterior cruciate ligament (ACL) reconstruction, although has rarely been reported in patients with ACL injuries that have not b...

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