Articles
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1,140 results found
Article
Mickey Mouse sign (disambiguation)
In medical imaging, a Mickey Mouse sign or appearance has been given to imaging features that mimic Mickey Mouse when viewed from the front. It has been described in the following:
anencephaly 2
progressive supranuclear palsy 1
synonymously with a finger in glove sign
the flared shape of the...
Article
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...
Article
Snowstorm sign (extracapsular breast implant rupture)
The snowstorm sign on breast ultrasound imaging represents the presence of free silicone droplets mixed with breast parenchymal tissue causing characteristic homogeneously hyperechoic dense shadowing with dispersion of the ultrasound beam. It is considered the most reliable sign of extracapsular...
Article
Tangent sign of supraspinatus muscle belly atrophy
The tangent sign is useful in helping to quantify supraspinatus muscle belly atrophy with a positive sign implicated with a poorer outcome after supraspinatus tendon tear repair.
Measurement
On a sagittal oblique plane, a line is drawn between the upper surface of the scapular spine and the up...
Article
Shiny corner sign (ankylosing spondylitis)
The shiny corner sign is a spinal finding in ankylosing spondylitis, representing reactive sclerosis secondary to inflammatory erosions at the superior and inferior endplates (corners on lateral radiograph) of the vertebral bodies, which are known as Romanus lesions. Eventually, the vertebral bo...
Article
Romanus lesion (vertebral bodies)
The Romanus lesion represents an early finding in inflammatory spondyloarthropathies, such as ankylosing spondylitis and enteropathic arthritis, and appears as irregularity and erosion involving the anterior and posterior edges of the vertebral endplates 1. Healing response to these inflammatory...
Article
Suspected physical abuse
Suspected physical abuse (SPA), also known as non-accidental injury (NAI) or inflicted injury, in infants and young children represents both ethical and legal challenges to treating physicians.
Radiologists may be the first clinical staff to suspect non-accidental injuries when confronted with ...
Article
Cone-shaped cecum (differential)
A cone-shaped cecum refers to a loss of the normal rounded appearance of the cecum, which instead becomes narrow and cone-shaped with the apex pointing towards the base of the appendix. It is encountered in a number of conditions including:
inflammatory
infective
blastomycosis
amoebiasis
Ye...
Article
Steinstrasse
Steinstrasse [stīn′shtra-se] is the German word for "stone street", describing a possible complication of extracorporeal shock wave lithotripsy (ESWL) for urinary tract calculi, wherein a column of stone fragments forms that blocks the ureter.
Terminology
The term steinstrasse can equally, alb...
Article
Hyperattenuating ring sign (epiploic appendagitis)
The hyperattenuating ring sign is a sign that has been described with epiploic appendagitis and intraperitoneal focal fat infarction. It refers to a hyperattenuating ring of visceral peritoneum. In the setting of epiplogic appendagitis, the ring would surround a thrombosed vascular pedicle with ...
Article
Venetian blind appearance (uterus)
The Venetian blind (a.k.a. rain shower 2) appearance is a sonographic finding that is typically associated with adenomyosis but can also occur in uterine fibroids. The Venetian blind appearance associated with adenomyosis is typically "thin" whereas when associated with uterine fibroids, there a...
Article
Prévost sign (eyes)
The Prévost sign, also known as the Vulpian sign or eye sign, refers to conjugate eye deviation in patients with acute stroke. The direction is variable, depending on the location of the stroke 3.
In a hemispheric stroke, the eyes deviate ipsilaterally towards the stroke (i.e. contralateral to ...
Article
Penumbra sign (bone)
In musculoskeletal radiology, the penumbra sign represents a rim of vascularized granulation tissue surrounding a bone abscess cavity, with a higher T1 signal intensity than the cavity itself 1. Presence of the penumbra sign can help distinguish acute osteomyelitis from other malignant and benig...
Article
Inverted Napoleon hat sign
The inverted Napoleon hat sign is a radiologic sign seen on the frontal pelvic or lumbar radiograph at the level of the 5th lumbar vertebra and the sacrum.
It is seen when there is bilateral spondylolysis with marked anterolisthesis of L5 on S1 or marked exaggeration of the normal lordosis at t...
Article
Butterfly vertebra
Butterfly vertebra, also sometimes known as a sagittal cleft vertebra or anterior rachischisis, is a type of vertebral anomaly that results from the failure of fusion of the lateral halves of the vertebral body because of persistent notochordal tissue between them.
Pathology
Butterfly vertebra...
Article
Butterfly sign (choroid plexus)
The butterfly sign refers to the normal appearance of the choroid plexuses on axial imaging of the fetal brain, commonly observed on the antenatal ultrasound. Its absence may suggest holoprosencephaly 1.
In the CNS, the term should not be confused with a butterfly glioma, which is a glioblastom...
Article
Butterfly glioma
Butterfly gliomas are high-grade astrocytomas, IDH-mutant or glioblastomas, IDH-wildtype that cross the midline via the corpus callosum. Other white matter commissures are also occasionally involved. The term butterfly refers to the symmetric wing-like extensions across the midline.
Butterfly ...
Article
Sliding sign
The sliding sign is a dynamic sonographic sign performed during transvaginal ultrasound (TVS) of women with suspected pelvic endometriosis. The loss of the normal sliding sign indicates pouch of Douglas (POD) obliteration due to adhesions and is suggestive of deep infiltrating endometriosis (DIE...
Article
Lipoma
Lipomas are benign tumors composed of mature adipocytes. They are the most common soft tissue tumor, seen in ~2% of the population.
Epidemiology
Patients typically present in adulthood (5th-7th decades).
Associations
In some cases, multiple lipomas are associated with syndromes and other di...
Article
Small heart sign
The small heart sign represents a rarely encountered but critical sign on chest caused by a sudden reduction of heart size caused by cardiac tamponade due to either tension pneumopericardium or pneumomediastinum.
A sudden, >2 cm reduction in the transverse cardiac diameter is considered highly...
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