Items tagged “signs”
76 results
Article
Positive metacarpal sign
In the metacarpal sign, a line drawn along the heads of the 4th and 5th metacarpals will intersect the head of the 3rd metacarpal if shortening is present. The shortened 4th metacarpal is the key to the sign.
The sign is positive in up to 9.6% of normal individuals 3. It is however seen in a va...
Article
Open ring sign
The open ring sign is a relatively specific sign for demyelination, most commonly multiple sclerosis (MS), and is helpful in distinguishing between the causes of ring-enhancing lesions.
Radiographic features
The enhancing component is thought to represent advancing front of demyelination and ...
Case
Fat halo sign
Published
07 May 2008
56% complete
CT
Article
Caput medusae sign (developmental venous anomaly)
The caput medusae sign also sometimes known as a palm tree sign refers to developmental venous anomalies of the brain, where a number of veins converge centrally into a single draining vein.
The sign is seen on both CT and MRI when contrast medium is administered. Angiographically the caput me...
Case
Corpus callosum lipoma - bracket sign
Published
07 Dec 2015
83% complete
CT
X-ray
Case
Air crescent sign
Published
22 Feb 2010
55% complete
CT
Case
Rigler sign
Published
25 Feb 2010
63% complete
X-ray
Article
Fallen fragment sign
The fallen fragment sign refers to the presence of a bone fracture fragment resting dependently in a cystic bone lesion. This finding was once thought to be pathognomonic for a simple (unicameral) bone cyst following a pathological fracture, although it has occasionally been reported with other ...
Case
Deep sulcus sign
Published
19 Mar 2011
50% complete
X-ray
Case
Subdiaphragmatic free gas
Published
19 Mar 2011
60% complete
X-ray
Case
Spinal cord metastasis
Published
13 May 2011
80% complete
MRI
Case
Cartilage interface sign - supraspinatus tear
Published
05 Jul 2011
71% complete
Ultrasound
Annotated image
Article
Pancake brain
Pancake brain is the classical sign of alobar holoprosencephaly. It is due to fusion of the cerebral hemispheres leaving a single ventricle in its centre. It is the most severe form of holoprosencephaly. It is associated with multiple facial abnormalities.
See also
pancake vertebra
vegetable ...
Article
White cerebellum sign
White cerebellum sign, also called reversal sign or dense cerebellum sign, is encountered when there is a diffuse decrease in density of the supratentorial brain parenchyma, with relatively increased attenuation of the thalami, brainstem and cerebellum. This sign indicates irreversible brain dam...
Article
Bare orbit sign (sphenoid wing)
The bare orbit sign, is described as a characteristic appearance of the orbit, seen when the innominate line is absent. The innominate line is a projection of the greater wing of the sphenoid, and its absence or destruction is responsible for this appearance.
It is the classical frontal radiogr...
Article
Leopard skin sign (white matter)
The leopard skin sign (also known as tigroid pattern or stripe sign) results from dark spots or stripes (spared perivascular white matter) within bright demyelinated periventricular white matter on T2W images. It is characteristically seen in:
metachromatic leukodystrophy
Krabbe disease 2
Pel...
Article
Tau sign
The tau sign represents the appearance of a persistent primitive trigeminal artery on the sagittal plane of an angiogram or on sagittal MRI images. It resembles the Greek letter τ, pronounced "tau", and is equivalent to the modern-day "T" in the Latin alphabet.
The persistent trigeminal artery ...
Case
Pneumoperitoneum
Published
13 Sep 2012
91% complete
X-ray
Case
H-shaped vertebrae
Published
18 Sep 2012
69% complete
X-ray
Case
Frimann-Dahl sign of sigmoid volvulus
Published
05 Dec 2012
91% complete
X-ray
Annotated image