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Aniridia

Aniridia refers to either the clinical sign of a complete/partial absence of the iris, or more specifically to the disease entity classic aniridia. Rarely other genetic conditions may cause this sign. Epidemiology Classic aniridia is inherited as an autosomal dominant condition and is seen in ...

Anisocoria

Anisocoria is present when an individual's pupils differ in size. If a person's pupils are symmetric there is said to be isocoria. Epidemiology The prevalence of transient physiological anisocoria of >0.4 mm is found in up to 20% population. However persistent anisocoria seems to be rarer, in ...

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.

Battle sign (base of skull fracture)

Battle sign is an eponymous term given to mastoid ecchymosis (bruising of the scalp overlying the mastoid process) and is strongly suggestive of a base of skull fracture, most commonly a petrous temporal bone fracture. History and etymology Mr William Henry Battle (1855-1936) was an English s...

Black turbinate sign (nasal cavity)

The black turbinate sign refers to the non-enhancement of nasal turbinates in a patient with acute invasive fungal rhinosinusitis. Angioinvasive fungal infection (e.g. mucormycosis or aspergillosis) involves the nasal mucosa and causes infarction of the surrounding tissue. The infarcted tissue ...

Broken heart sign

The broken heart sign, also known as the Y sign in older otorhinolaryngology literature 2,3, describes the appearances of incudomalleolar disarticulation. This sign is identified on CT in the coronal plane, being formed by the widening of the incudomalleolar joint and lateral displacement of th...

Capps triad

The Capps triad refers to the constellation of clinical and imaging findings in patients with spontaneous retropharyngeal hematomas, and consists of: tracheal and esophageal compression anterior displacement of the trachea subcutaneous bruising over the neck and anterior chest History and et...

Cloverleaf skull (craniosynostosis)

Cloverleaf skull, also known as kleeblattschädel syndrome or deformity, refers to a type of severe craniosynostosis which gives the skull a cloverleaf shape. It is very rare, with less than 130 case reports globally. It typically results from intrauterine premature closure of the sagittal, coron...

Coca-Cola bottle sign (thyroid eye disease)

The Coca-Cola bottle sign refers to the appearance of the muscles of the orbit in thyroid eye disease. The belly of the muscle enlarges with sparing of the tendinous insertion, giving the appearance of the traditional Coca-Cola bottle. The enlargement of the muscles follows the I'M SLOW format...

Convoluted cerebriform pattern

A convoluted cerebriform pattern is a term used to denote the appearance of a sinonasal inverted papilloma on MRI. The appearance is seen on both T2 and post contrast T1 images and appears as alternating roughly parallel lines of high and low signal intensity. This sign has been reported as pre...

Double disc sign

Thickening of the insertion of the lateral pterygoid muscle can mimic an anterior displaced temporomandibular disc. When both thickening of the inferior belly insertion and an anteriorly displaced disc are present, as in temporomandibular joint dysfunction, the two structures parallel each other...

Doughnut sign (disambiguation)

The doughnut sign can refer to a variety of different signs: doughnut sign (bone scan) doughnut sign (bowel) crescent in a doughnut sign (bowel) doughnut sign (chest) doughnut sign (orbit)

Doughnut sign (orbit)

The doughnut sign of optic nerve sheath meningioma refers to the appearance of this tumor on coronal CT/MRI. The meningioma forms a thick cuff of enhancing tumor around the central non-enhancing optic nerve, mimicking the appearance of a ring doughnut. It is the coronal equivalent of the tram-tr...

Fistula test

The fistula test is used when examining a patient with recurrent vertigo. A finger is abruptly applied to the external meatus which causes a pulse of air-transmitted pressure. If nystagmus is induced in association with vertigo, it indicates bony destruction within the inner ear e.g. cholesteat...

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 tumor cells.

Geographic skull

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

Giraffe pattern

Giraffe pattern (also known as the pseudonodular appearance) is a distinctive ultrasound appearance characteristic of Hashimoto thyroiditis. Bonavita originally described a thyroid gland with multiple echogenic nodules, separated from one another by bands of hypoechogenicity, reminiscent of a gi...

Griesinger sign (mastoid)

The Griesinger sign refers to edema 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 associated with dural sinus occlusive disease (DSOD). It is said to be a pathognomon...

Guitar pick sign (orbits)

Guitar pick sign refers to conical deformation (tenting) of the posterior ocular globe indicating severely increased intraorbital pressure (orbital compartment syndrome) Presence of a guitar pick sign on imaging is associated with acute and permanent visual damage.

Guttman test (larynx)

The Guttman test is a clinical test 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.

Harlequin eye deformity

The harlequin eye deformity is characterized by elevation of the superolateral corner of the orbit. It may be seen in unilateral (plagiocephaly) or bilateral (brachycephaly) coronal suture synostosis. History and etymology The term harlequin eye derives from the appearance of the eyes on a har...

Hennebert sign (inner ear)

The Hennebert sign describes a positive fistula test without clinical evidence of middle ear or mastoid disease. It is associated with congenital syphilis and may also be present in Ménière disease. It has been postulated that the vestibular stimulation is mediated by fibrous bands between foot...

Hockey stick sign (disambiguation)

The hockey stick sign can refer to a variety of different signs and appearances: hockey stick sign (thyroid hemiagenesis) hockey stick sign (Creutzfeldt-Jakob disease) hockey stick sign (ureters)

Hockey stick sign (thyroid hemiagenesis)

Hockey stick sign has been used to describe the appearance of the thyroid gland in cases of thyroid hemiagenesis when investigated with thyroid scan (Tc-99m) 1. The unilateral lobe and isthmus make a shape reminiscent of a hockey stick. See also hockey stick sign (Creutzfeldt-Jakob disease)

Holman-Miller sign (maxillary sinus)

The Holman-Miller sign (also called the antral sign) is seen in juvenile nasopharyngeal angiofibroma; it refers to the anterior bowing of the posterior wall of the maxillary antrum as seen on a lateral skull radiograph or cross-sectional imaging 1,2. This is a non-specific sign that can be prod...

Hutchinson sign (disambiguation)

The Hutchinson sign can refer to two clinical signs. Hutchinson sign (ophthalmology) Relates to involvement of the tip of the nose from facial herpes zoster. It implies involvement of the external nasal branch of the nasociliary nerve (branch of the ophthalmic division of the trigeminal nerve...

Hutchinson teeth

Hutchinson teeth are smaller and more widely spaced than normal and are notched on their biting surfaces. It is a sign of congenital syphilis and should not be confused with: Hutchinson triad Hutchinson pupil Hutchinson freckle Hutchinson sign Hutchinson syndrome History and etymology Na...

Hyoid elevation

Hyoid elevation on a modified barium swallow study indicates that the pharyngeal muscles are contracting appropriately. Radiographic features Modified barium swallow With real time fluoroscopy (or videofluoroscopy) during the act of swallowing, the larynx moves upward and forward when there i...

Ice cream cone sign (disambiguation)

The ice cream cone sign may refer to: ice cream cone sign (middle ear ossicles) ice cream cone sign (vestibular schwannoma)

Ice cream cone sign (vestibular schwannoma)

The ice cream cone sign refers to the appearance of a medium-sized (1.5 to 3.0 cm) vestibular schwannoma. The intracanalicular component represents the cone and the cerebellopontine angle (CPA) (cisternal) component representing the ice cream ball. See also ice cream cone sign (middle ear ossi...

Kayser-Fleischer rings

Kayser-Fleischer rings, sometimes shortened to K-F rings, are caused by copper deposition in the cornea and are a specific, clinical sign of Wilson disease. Clinical presentation They are usually brown or dark reddish in color. Early on they may need a slit lamp to be visible before they becom...

Kissing carotids

The term kissing carotids refers to tortuous and elongated vessels which touch in the midline. They can be found in: retropharynx 2 intrasphenoid 1 within the pituitary fossa within sphenoid sinuses within sphenoid bones The significance of kissing carotids is two-fold: may mimic intrase...

Low attenuation lymphadenopathy

Low attenuation lymphadenopathy refers to abnormal lymph nodes that on CT appear to have lower attenuation than other soft tissues. This category can be split into two types: cystic (necrotic) lymph nodes metastatic carcinoma (or lymphoma) infections (tuberculous or fungal) cavitating mesent...

Lyre sign (carotid artery)

The lyre sign refers to the splaying of the internal and external carotid by a carotid body tumor. Classically described on angiography it is also visible on CT angiography.

Martini glass sign

The Martini glass sign describes the appearance of the globe in persistent hyperplastic primary vitreous (PHPV). On MRI the retrolenticular tissue characteristic of this condition has a triangular shape, like that of a martini glass appearing as low T2 signal against the normal high T2 signal o...

Morning glory syndrome (eye)

Morning glory disc anomaly (MGDA), also known as morning glory syndrome, is a rare congenital malformation of the optic nerve which is frequently associated with midline abnormalities of the brain and skull 1. Epidemiology Morning glory disc anomaly is rare and is more commonly found in female...

Optic nerve calcification

Optic nerve calcification is a rare radiological finding, with only a short differential diagnosis, many of which have only been described in isolated case reports 1-4. Differential diagnosis optic nerve meningioma optic nerve head drusen idiopathic dural optic nerve sheath calcification ca...

Orbital emphysema

Orbital emphysema is the presence of gas within the orbital soft tissues. It is usually due to orbital fractures communicating with the paranasal sinuses but can be caused by penetrating trauma and infection. It is a common finding also after orbital or ocular surgery. Location preseptal pos...

Perilymphatic fistula

A perilymphatic fistula (also known as a labyrinthine fistula) is a pathologic communication between the fluid-filled space of the inner ear and the air-filled space of the middle ear, most commonly occurring at either the round or oval window. Clinical presentation Symptoms of perilymphatic ...

Polycoria

Polycoria is the presence of more than one true pupil in the iris, each possessing their own fully functional sphincter pupillae muscle, which responds appropriately to light and drugs. It is a very rare entity with only a few case reports in the global literature 1,2. Pseudopolycoria occurs whe...

Powers ratio

The Powers ratio is a measurement of the relationship of the foramen magnum to the atlas, used in the diagnosis of atlanto-occipital dissociation injuries. The ratio, AB/CD, is measured as the ratio of the distance in the median (midsagittal) plane between the: basion (A) and the posterior spi...

P sign

The alphabet P sign, or just P sign, is a sonographic finding in acute epiglottitis. Using point of care ultrasound (POCUS), on a longitudinal view at the level of the thyrohyoid membrane, a P-shaped hypoechogenicity is apparent. The curved portion of the P is formed from the edematous epiglotti...

Ptosis

Ptosis (or blepharoptosis) is a drooping or falling of the upper eyelid. Complete ptosis is due to complete oculomotor nerve palsy. Partial ptosis is due to a dysfunction of the sympathetic pathway leading to paralysis of Muller muscle. Note that facial nerve paralysis prevents screwing of the...

Raccoon eyes sign (base of skull fracture)

Raccoon eyes sign (or panda eyes in the UK and Ireland) refers to periorbital ecchymosis with sparing of the tarsal plate 3 and is a physical examination finding indicative of a base of skull fracture of the anterior cranial fossa. However it is not pathognomonic for trauma, and there are sever...

Raindrop skull

The raindrop skull appearance of calvarial multiple myeloma is the presence of multiple, well-defined lytic lesions (punched out lesions) of various size scattered throughout the skull. This term is applied as an analogy to rain hitting a surface and splashing, where it leaves a random pattern o...

Romaña sign (Chagas disease)

Romaña sign, also known as the periorbital swelling syndrome, refers to periorbital swelling, palpebral edema and conjunctivitis seen 1-2 weeks following infection with Trypanosoma cruzi (causative agent in Chagas disease). When present it is diagnostic of acute Chagas disease. Romaña sign is a...

Sack of marbles sign (dermoid cyst)

The sack of marbles sign, also known as the marbles in a bag sign, refers to aggregations of multiple small globules of fat within a cyst mimicking marble spheres within a sack. They appear hyperechoic on ultrasound, fat attenuation on CT, and high signal on T1WI and T2WI on MRI. It is considere...

Sail sign (disambiguation)

There are numerous sail signs in radiology, where a normal structure is displaced or a pathology creates the appearance of a sail: elbow sail sign: the raised anterior fat pad on an elbow radiograph thymic sail sign: normal thymus on a pediatric chest radiograph spinnaker-sail sign (angel win...

Sail sign (larynx)

The sail sign of the larynx refers to the axial appearance of unilateral dilatation of the laryngeal ventricle due to vocal cord/fold paralysis. It should not be confused with the several other sail signs in radiology. Radiographic features CT Axial images at the level of the glottis show the...

Salt and pepper sign (skull)

Salt and pepper sign or pepper pot skull refers to multiple tiny well-defined lucencies in the calvaria caused by resorption of trabecular bone in hyperparathyroidism. There is a loss of definition between the inner and outer tables of the skull and a ground-glass appearance as well as spotty de...

Schwartze sign

Schwartze sign also known as Flemingo's flush sign or Rising sun sign is a characteristic reddish discolouration of the promontory seen during an otoscopic examination. It is seen in cases with otospongiosis in the active phase of the disease 3. History and Etymology Named after German otologi...

Sitting duck appearance (jugular foramen)

The sitting duck appearance denotes the normal anatomical configuration of the jugular foramen: the head of the duck (pointing backwards on the right side) represents the anteromedial pars nervosa the body of the duck representing the pars vascularis

Snake eyes (facial nerve)

Snake eyes, also known as snail eyes, is a term used to refer to the appearance of the facial nerve on coronal CT within its canal in the petrous temporal bone as the tympanic segment doubles back next to the labyrinthine segment. Anteriorly, these two segments converge at the geniculate ganglio...

Snowman sign (disambiguation)

Snowman sign, also sometimes referred to as a figure of 8 sign or dumbell sign, is a radiologic sign related to conditions that have a shape which resembles a snowman. This include: snowman sign (total anomalous pulmonary venous return) 1 snowman sign (pituitary macroadenoma) 2,3

Snowman sign (pituitary macroadenoma)

Snowman sign in neuroimaging refers to the configuration of many pituitary macroadenomas. As they are soft tumors they are indented by the diaphragma sellae giving them a snowman configuration (or "figure 8" or "dumbbell" configuration). This feature helps in differentiating these tumors from me...

Stuck temporomandibular joint disc

A stuck disc, also called anchored disc phenomenon, refers to a temporomandibular joint (TMJ) disc which does not translate anteriorly out of the mandibular fossa onto the articular eminence but rather remains (thus "stuck") in the fossa. It is a form of TMJ dysfunction. Clinical presentation ...

Thumb sign (epiglottitis)

The thumb sign in epiglottitis is a manifestation of an edematous and enlarged epiglottis which is seen on lateral soft-tissue radiograph of the neck, and it suggests a diagnosis of acute infectious epiglottitis. This is the radiographic corollary of the omega sign 1-3. See also Thumb sign is ...

Thyroid inferno

Thyroid inferno refers to the color Doppler appearance of the thyroid gland in active Graves disease (inclusive of variants such as Marine-Lenhart syndrome) and consists of multiple small areas of color flow seen diffusely throughout the gland representing increased vascularity and arteriovenous...

Trousseau sign

Trousseau sign of latent tetany (not to be confused with Trousseau syndrome) is highly specific for hypocalcemia 1. It may be elicited by placing a blood pressure cuff over the upper arm and inflating to above systolic pressure for 2-3 minutes. This reduces arterial supply to the forearm. The is...

Trumpeted internal acoustic meatus sign

A trumpeted internal acoustic meatus (IAM) is an indirect sign of a vestibular schwannoma and is useful in helping to differentiate between one and other cerebellopontine angle entities, especially from a meningioma which typically does not extend into the meatus and is more often associated wit...

Tullio phenomenon

The Tullio phenomenon describes the precipitation of vertigo and nystagmus by a loud noise. Pathology Etiology The tympanic membrane and ossicular chain must be intact with a mobile footplate. It may be seen in several situations: Ménière disease superior semicircular canal dehiscence syndr...

Widow's peak hair anomaly

Widow's peak hair anomaly refers to a frontal hairline projection. Epidemiology Associations Aarskog syndrome Opitz syndrome Waardenburg syndrome frontonasal dysplasia craniofrontonasal dysplasia Clinical presentation Prominent V-shaped hairline projection. Ocular hypertelorism might be...

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