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23 results found

Gage sign

Gage sign is a V-shaped lucent defect at the lateral portion of the epiphysis and/or adjacent metaphysis. It is pathognomonic to Legg-Calve-Perthes disease. It may occur early in the disease and is one of the  five indicators of a worse prognosis, which are: Gage sign  calcification lateral t...

Galaxy sign (lungs)

The so-called galaxy sign, initially described as the sarcoid galaxy, represents a coalescent granuloma seen in a minority of patients with pulmonary sarcoidosis 1. The same appearance can be seen in tuberculosis 2,3. In other words, it represents a mass-like region composed of numerous smaller ...

Gamekeeper thumb

Gamekeeper thumb is essentially synonymous with skier thumb, although the latter has a more acute injury connotation. It is an avulsion or rupture of the ulnar collateral ligament (UCL) of the thumb.  Epidemiology The repetitive breaking-of-necks of small game (rabbits and such) resulted in ch...

Garland triad

Garland triad, also known as the 1-2-3 sign or Pawnbrokers sign, is a lymph node enlargement pattern which has been described in sarcoidosis: right paratracheal nodes right hilar nodes left hilar nodes Hilar lymphadenopathy is symmetrical and usually massive. These so-called potato nodes don...

Garrington sign (teeth)

Garrington sign is thickening of the periodontal ligament/membrane space of involved teeth in the setting of gnathic osteosarcoma. Symmetrical widening of the space can be seen early in the disease process due to infiltration of tumour cells. 

Genu recurvatum

Genu recurvatum describes the malalignment or deformity of the knee joint with extension beyond neutral (i.e. hyperextension).  Pathology Genu recurvatum can be associated with subluxation or dislocation of the knee joint.  Aetiology congenital arthrogryposis multiplex congenita congenital...

Geographic skull

A geographic skull is a radiographic appearance which is seen at eosinophilic granuloma (EG) and characterized by destructive lytic bone lesion, edges of which may be bevelled, scalloped or confluent.

Geyser sign (shoulder)

The geyser sign may occur in some cases of long-standing rotator cuff tear and advanced degenerative change of the shoulder.  Clinical presentation It may present as a pseudotumour above the AC joint. Pathology Chronic rotator cuff degenerative change and full-thickness tearing leads to inst...

Ghon lesion

A Ghon lesion (sometimes called Ghon focus) represents a calcified tuberculous caseating granuloma (tuberculoma) and represents the sequelae of primary pulmonary tuberculosis infection. When associated with a calcified ipsilateral hilar node it is known as a Ranke complex.

Ghost meniscus

The term "ghost meniscus", also known as empty meniscus sign, refers to a large radial tear that has completely transected the meniscus or, alternatively, previous meniscectomy. Radiographic features MRI On MRI knee when the slice plane is exactly in line with the meniscal tear this can produ...

Ghost sign (cervical spine)

Ghost sign is a feature that has been described in Clay shoveler fracture as can be seen on the AP projection of a cervical spine radiograph. It is caused by the appearance of a "double spinous process" on C6 or C7 resulting from caudal displacement of the avulsed spinous process fragment, givin...

Ghost vertebra

Ghost vertebra is a sign that can refer to a varied abnormal radiographic appearance of the vertebrae due to a number of different entities: thorotrast administration: bone within a bone appearance due to temporary growth arrest 1 osteopaenia: such loss of trabecular pattern that the vertebra ...

Ginkgo leaf sign (chest)

The ginkgo leaf sign of the chest, also referred as the ginkgo leaf sign of subcutaneous emphysema, is a radiograph appearance which is seen at extensive subcutaneous emphysema of the chest wall. Air outlines the fibers of the pectoralis major muscle and creates a branching pattern that resemble...

Girdlestone procedure

The Girdlestone procedure (also known as a femoral head ostectomy or Girdlestone resection arthroplasty) is an excision arthroplasty of the hip. The procedure inevitably results in limb shortening. Indications  peri-prosthetic infection aseptic loosening recurrent dislocation failed interna...

Glenoid labrum ovoid mass sign

The glenoid labrum ovoid mass (GLOM) sign (seen on MRI) is useful when a torn anterior glenoid labrum retracts superiorly.  Seen typically on a T2 axial image through the glenohumeral joint as a low signal ovoid mass anterior to the glenoid labrum.  Sometimes this can be the only sign of a torn...

Goblet sign (ureter)

The goblet sign (or champagne glass sign) refers to the appearance of the ureter when it is focally dilated by an intraluminal mass. It is best seen when the ureter is opacified from below, by a retrograde ureterogram. Presence of this sign indicates the pathology to be chronic, permitting the l...

Golden S-sign (lung lobe collapse)

The Golden S-sign is seen on both PA chest radiographs and on CT scans. It is named because this sign resembles a reverse S shape, and is therefore sometimes referred to as the reverse S-sign of Golden. Although typically seen with right upper lobe collapse, the S-sign can also be seen with the...

Gosselin fracture

The Gosselin fracture is a fracture of distal tibia with a V-shaped fractured fragment and intraarticular involvement. History and etymology It is named after Leon Athanese Gosselin (1815–1887), a French surgeon.

Grey cortex sign (stress fracture)

The grey cortex sign was described as an early sign of stress (fatigue) fractures on conventional radiographs and refers to subtle ill definition of the cortex. However, conventional radiography is insensitive for the detection of early-stage fatigue fractures. CT is much more sensitive for det...

Griesinger sign (mastoid)

Griesinger sign, named after Wilhelm Griesinger, a German psychiatrist and neurologist (1817-1868) refers to oedema of the postauricular soft tissues overlying the mastoid process as a result of thrombosis of the mastoid emissary vein. It is a complication of acute otomastoiditis and may be asso...

Gull wing appearance (phalanges)

The Gull-wing appearance  (also known as seagull erosions) is seen in erosive osteoarthritis, typically on posteroanterior (PA) radiographs. The combination of cartilage space loss, central subchondral erosions, and marginal osteophyte proliferation results in a gull-wing appearance.

Gut signature sign

The gut signature sign is an ultrasound term used to describe the appearance of the gastrointestinal wall. Radiographic features  Ultrasound Bowel has 5 layers, comprised of alternating hyperechoic and hypoechoic layers. Anatomically these layers are as follows (innermost to outermost) 1,2: ...

Guttman sign (larynx)

Guttman sign is a clinical sign relating to the function of the larynx. In normal subjects, frontal pressure on the thyroid cartilage lowers the tone of voice produced and lateral pressure produces a higher tone of voice. The opposite is true with paralysis of the cricothyroid muscle.

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