Articles

Articles are a collaborative effort to provide a single canonical page on all topics relevant to the practice of radiology. As such, articles are written and edited by countless contributing members over a period of time. A global group of dedicated editors oversee accuracy, consulting with expert advisers, and constantly reviewing additions.

2,247 results found
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Dysgenesis of the corpus callosum

Dysgenesis of the corpus callosum may be complete (agenesis) or partial and represents an in utero developmental anomaly. It can be divided into: primary agenesis: the corpus callosum never forms secondary dysgenesis: the corpus callosum forms normally and is subsequently destroyed Epidemiolo...
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Dysgerminoma

A dysgerminoma refers to a class of tumour with germ cell origin. This can refer to: CNS dysgerminoma ovarian dysgerminoma See also germ cell tumours
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Dysmyelinating disorders

Dysmyelinating disorders are a subset of white matter disorders characterised by abnormal myelination 1. They are also known by the term leukodystrophy and are composed of a group of inherited conditions that are characterised by a defective structure and function of the myelin sheath 2. They a...
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Early DWI reversal in ischaemic stroke

Early DWI reversal in ischaemic stroke (also referred to as diffusion lesion reversal) is encountered early in the course of ischaemic infarction, most frequently in the setting of reperfusion within 3 to 6 hours of onset 1. In the vast majority of cases it is transient and does not represent tr...
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Eastern equine encephalitis

Eastern equine encephalitis (EEE) is one of many viral encephalitides and results from infection with the eastern equine encephalitis virus. Clinical presentation Most patients have non-specific viral prodromal symptoms for approximately one week, including fevers, headache, nausea and vomitin...
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EBV associated smooth muscle tumour

Epstein-Barr virus-associated smooth muscle tumours (EBV-SMT) are rare and encountered in immunocompromised individuals. Epidemiology These tumours are generally exceedingly rare, and only seen with any frequency in the setting of immunosuppression, particularly in HIV/AIDS patients, but also ...
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EBV-positive diffuse large B-cell lymphoma, NOS

EBV-positive diffuse large B-cell lymphoma, NOS (not otherwise specified) is one of the immunodeficiency-associated CNS lymphomas, usually seen in elderly individuals. Unlike other EBV-associated CNS lymphomas, these individuals do not have a defined cause for immunosuppression. It is believed t...
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Eccentric target sign (cerebral toxoplasmosis)

The eccentric target sign is considered pathognomonic for cerebral toxoplasmosis. It is seen on postcontrast MRI/CT as a ring enhancing lesion with an eccentrically located enhancing mural nodule. It is believed that this mural nodule is an extension from the abscess wall itself with inflamed ve...
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Ecchordosis physaliphora

Ecchordosis physaliphora is a congenital benign hamartomatous lesion derived from notochord remnants, usually located in the retroclival prepontine region, but can be found anywhere from the skull base to the sacrum.  Terminology There has been some controversy as to whether intradural chordom...
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Ectopia lentis

Ectopia lentis refers to subluxation or dislocation of the lens of the eye secondary to dysfunction or disruption of zonular fibres.  Pathology Aetiology trauma systemic and syndromic disorders Marfan syndrome typically upwards and out most common spontaneous cause 2 homocystinuria -  ty...
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Ectopic posterior pituitary

An ectopic posterior pituitary reflects a disruption of normal embryogenesis of the posterior pituitary and is one of the more common causes of pituitary dwarfism. Although it can be an isolated abnormality, numerous other congenital central nervous system malformations have been identified. Ep...
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Edinburgh criteria for lobar intracerebral haemorrhage associated with cerebral amyloid angiopathy

The Edinburgh criteria were proposed in 2018 in order to diagnose lobar intracerebral haemorrhage associated with cerebral amyloid angiopathy (CAA) 1. They can potentially be used to rule CAA-associated lobar haemorrhage either in or out, but require external validation in other patient populati...
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Efface

Efface is a term frequently used by radiologists, most often in the context of CSF-containing spaces in the brain (sulci and ventricles). Unfortunately, it is often used incorrectly.  The word efface, in general English usage, means to cause something to fade or disappear 1,2. In the context o...
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Elevated prolactin (differential)

Elevated prolactin can be due to a number of causes, including elevated production/secretion as well as reduced inhibition.  Prolactin is controlled by numerous homeostatic mechanisms, with tonic secretion of prolactin inhibitory hormone (dopamine) by the hypothalamus having a dominant effect 1...
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Eloquent cortex

Eloquent cortex is a term that refers to specific brain areas that directly controls function, thus damage to this areas generally produces major focal neurological deficits. Examples of eloquent cortex are:  primary motor cortex (precentral gyrus) primary somatosensory cortex (postcentral gyr...
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Embryonal tumours with multilayered rosettes (ETMR)

Embryonal tumours with multilayered rosettes (ETMR) are rare small round blue cell tumour of the central nervous system and are one of the most aggressive brain tumours usually encountered in children.  Terminology Previously embryonal tumours with multilayered rosettes (ETMR) were known as em...
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Emergency CT head (mnemonic)

A useful mnemonic which is used to read an emergency head CT scan is: Blood Can Be Very Bad Mnemonic Using a systematic approach will help to ensure that significant neuropathology will not be missed. B: blood look for epidural hematoma, subdural hematoma, intraparenchymal hemorrhage, intra...
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Empty delta sign

The empty delta sign is a CT sign of dural venous sinus thrombosis of the superior sagittal sinus, where contrast outlines a triangular filling defect, which represents thrombus. It is only described with CECT-scan or MRI, not with NECT nor non-contrast MRI. An equivalent appearance can be note...
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Empty light bulb sign in brain death

In brain death, on HMPAO-Tc99m imaging there is absent or reduced flow in the internal carotid arteries and increased flow within the external carotid arteries. This leads to absent uptake in the brain with subsequent increased perfusion in the nasal region. This appearance has been called the e...
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Empty sella

An empty sella, also known as an empty pituitary fossa, is a relatively common incidental finding and posed more of a diagnostic problem before modern cross-sectional imaging. In addition to being incidental, a well-established association with benign intracranial hypertension is also recognised...
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Empty thecal sac sign

The empty thecal sac sign or empty sac sign is when the thecal sac appears empty on MRI of the lumbar spine, best seen on T2-weighted images. If the empty thecal sac sign is present, a diagnosis of adhesive arachnoiditis can be made.​ Radiographic features MRI There is usually no gadolinium c...
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Empyema

Empyemas are purulent inflammatory collections within a body cavity. They are similar to abscesses, which arise within parenchymal tissue rather than occupying a pre-existing anatomical space. Terminology Colloquially, the term empyema is used to refer to thoracic empyemas but there are variou...
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Encephalitis due to herpesvirus family

Although sporadic viral encephalitis is most commonly due to herpes simplex virus 1 (HSV-1) the extended herpesvirus family consists of many other viruses many of which can also infect the central nervous system. Encephalitis due to herpesvirus family include 1:   herpes simplex virus 1 (HSV-1)...
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Encephalitis lethargica

Encephalitis lethargica, also known as von Economo encephalitis, is a rare disease of unknown aetiology that affects the midbrain and basal ganglia.  Clinical presentation Symptoms are initially that of pharyngitis followed by lethargy, extrapyramidal movements (parkinsonism and dyskinesias), ...
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Encephalocele

Encephalocele, also known as meningoencephalocele, is a form of neural tube defect and a type of cephalocele where brain tissue and overlying meninges herniate out through a defect in the cranium.  Terminology It should be distinguished from cranial meningocele in which the lesion contains onl...
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Encephalocraniocutaneous lipomatosis

Encephalocraniocutaneous lipomatosis (ECCL), also known as Haberland syndrome, is a rare congenital neurocutaneous syndrome characterised by unilateral lipomas of the cranium, face, and neck, ipsilateral lipodermoids of the eye, and ipsilateral brain anomalies. The clinical features of ECCL ove...
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Encephalomalacia

Encephalomalacia is term given to describe softening or loss of brain parenchyma with or without surrounding gliosis, as a late manifestation of injury.  Clinical presentation asymptomatic  serve as a focus of seizure Pathology Encephalomalacia is the end result of liquefactive necrosis of ...
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Endolymphatic sac tumour

Endolymphatic sac tumours are very rare, locally invasive tumours of endolymphatic sac. Early detection of these tumours is critical, because early surgical intervention may prevent further hearing loss. Endolymphatic sac tumours do not metastasize but are highly locally aggressive.  Epidemiolo...
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Enlarged posterior fossa 'CSF' space

An enlarged posterior fossa 'CSF' space posterior to the cerebellum has a number of differentials that include: mega cisterna magna epidermoid cyst arachnoid cyst Careful attention to the cerebellum needs to paid as also to be considered are: cerebellar atrophy Dandy-Walker malformations ...
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Enlarged sella turcica (differential)

Enlargement of sella turcica can be seen in situations including the following: empty sella syndrome slight globular enlargement of the sella with no erosion, destruction or posterior displacement of dorsum sellae intracranial hypertension enlargement with erosion of anterior cortex of dorsu...
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En plaque meningioma

En plaque meningiomas refer to a specific meningioma macroscopic appearance characterised by diffuse and extensive dural involvement, usually with extracranial extension into calvarium, orbit, and soft tissues. These tumours are thought to have a collar-like or sheet-like growth along the dura m...
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Enterovirus 71

Enterovirus 71 is one of the viruses that causes hand-foot-and-mouth disease in children. It is an enterovirus, one of the picornaviruses. Infection with enterovirus 71 predominantly results in a vesicular rash of the hands and feet that follows a prodrome of symptoms including fever, vomiting ...
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Enterovirus rhomboencephalitis

Enterovirus rhomboencephalitis is the most common neurological complication of enterovirus infection 1. Clinical presentation Enterovirus rhomboencephalitis causes acute and severe neurologic disorders such as ataxia, nystagmus, oculomotor palsies, or bulbar palsy. In some cases, neurologic af...
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Entorhinal cortex

The entorhinal cortex (Brodmann area 28) is located in the mesial temporal lobe and acts as the interface between the hippocampus and the neocortex. It has been considered part of the hippocampal formation (along with Ammon’s horn, subiculum and presubiculum), but is difficult to precisely local...
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Eosinophilia myalgia syndrome

Eosinophilia myalgia syndrome (EMS) is a fatal neurological condition caused by ingestion of improperly manufactured L-tryptophan.  Impurities and/or metabolites that block histamine degradation result in peripheral blood eosinophilia and myalgia.   In the brain, cortical and basal ganglia atro...
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Ependymal cells

Ependymal cells are one of the four main types of glial cells, and themselves encompass three types of cells 1:  ependymocytes: line the ventricles of the brain and central canal of the spinal cord tanycytes: line the floor of the third ventricle choroidal epithelial cells: line the surface o...
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Ependymal cyst

Ependymal cysts are rare benign neuroepithelial cysts lined by ependymal cells. Most are small and asymptomatic and only cause symptoms if large. On imaging, these cysts are essentially indistinguishable from other intraventricular simple cysts (e.g. intraventricular arachnoid cysts). Epidemio...
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Ependymal rosettes (ependymoma)

Ependymal rosettes correspond to a histologic architectural pattern that very characteristic of ependymomas, as tumour cells form structures similar to the lining of normal ventricles. They are characterised by a halo or spoke-wheel arrangement of tumour cells surrounding an empty central tubule...
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Ependymitis granularis

Ependymitis granularis sounds far more worrying than it actually is. The term refers to symmetrical foci of periventricular high T2 and FLAIR signal hyperintensity anterior and lateral to the frontal horns. It is just an anatomical variant, usually small, less than 1 cm, and have a triangular mo...
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Ependymocytes

Ependymocytes are one of the three types of ependymal cells, which in turn are one of the four principles types of glial cells, and are found lining the ventricular system of the brain and the central canal of the spinal cord 1.  They do not form a water-tight barrier between the cerebrospinal ...
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Ependymoma

Ependymomas represent a relatively broad group of glial tumours most often arising from the lining the ventricles of the brain or the central canal of the spinal cord. They account for ~5% of all neuroepithelial neoplasms, ~10% of all paediatric brain tumours and up to 33% of brain tumours occur...
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Ependymoma RELA fusion-positive

Ependymoma RELA fusion-positive is a recently accepted variant of ependymoma, only recognised in the 2016 update to the WHO classification of CNS tumours. They are the most common type of supratentorial ependymoma in children, and not found in the posterior fossa or spinal cord.  Epidemiology ...
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Ependymoma vs astrocytoma of the spinal cord

A number of factors are useful when differentiating between spinal cord ependymoma and spinal cord astrocytoma.  Ependymoma child or adult more central in location bone remodelling is common low T1 signal well-defined enhancement syrinx is more common haemorrhage is more common Astrocyt...
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Epidermoid cyst

The term epidermoid cyst can refer to a: epidermal inclusion cyst intracranial epidermoid cyst splenic epidermoid cyst spinal epidermoid cyst testicular epidermoid cyst
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Epidural angiolipoma

Epidural angiolipomas are rare benign tumours composed of mature adipocytes and abnormal vessels.  Epidemiology Epidural angiolipomas are more frequently encountered in women, and typically in middle age (40-50 years of age) 1.  Clinical presentation In keeping with the slow growth of these ...
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Epidural blood patch

Epidural blood patch is a treatment option for patients with craniospinal hypotension or post lumbar puncture headaches. The procedure can be done blind or under fluoroscopic or CT guidance, and is performed predominantly by radiologists and anaesthetists.  Indications craniospinal hypotension...
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Epidural empyema

Epidural empyema refers to a collection within the epidural space either within the cranium or the spinal cord. Epidemiology Epidural empyemas are rare overall but together with subdural empyema account for around 20-33% of all intracranial infections. They can present in any age group and hav...
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Epidural lipomatosis

Epidural lipomatosis refers to an excessive accumulation of fat within the spinal epidural space resulting in compression of the thecal sac. In severe cases, compression may be symptomatic. The lumbar region is most frequently affected. Epidemiology The demographics of affected individuals ref...
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Epilepsy

Epilepsy is a common neurological disorder that has a varied presentation and requires two or more unprovoked seizures at least 24 hours apart for diagnosis. MRI is the modality of choice for epilepsy, most often investigating for an underlying cause, especially in adults.  Epidemiology Epilep...
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Epilepsy protocol (MRI)

MRI protocol for epilepsy is a group of MRI sequences put together to improve sensitivity and specificity in identifying possible structural abnormalities that underlie seizure disorders (e.g. mesial temporal sclerosis and malformation of cortical development). MRI is the imaging procedure of ch...
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Epithalamus

The epithalamus is a dorsal posterior segment of the diencephalon which includes the habenula, stria medullar is, pineal gland and posterior commissure. Its function is the connection between the limbic system to other parts of the brain.
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Epithelial membrane antigen (EMA)

Epithelial membrane antigen (EMA) is a commonly used target for immunohistochemisty, found on the surface of many epithelial cells and thus present in a wide variety of tumours. It also is sometimes seen within the cytoplasm of cells (e.g. perinuclear dot in ependymomas). 
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Epithelioid glioblastoma

Epithelioid glioblastoma is a variant of glioblastoma (along with gliosarcoma and giant cell glioblastoma) only recently added to the WHO classification of CNS tumours as part of the 2016 update 1.  Terminology Whether or not epithelioid glioblastomas are distinct from rhabdoid glioblastomas i...
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Epstein-Barr virus encephalitis

Epstein-Barr virus (EBV) encephalitis is an uncommon manifestation of EBV infection and an uncommon causative organism of encephalitis in general. Epidemiology Most reported cases have been in children, although adults can rarely be affected 5. Clinical presentation Primary EBV infection is ...
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Erdheim-Chester disease

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell, non-familial multisystemic granulomatosis, with widespread manifestations and of highly variable severity. The most common presenting symptom is bone pain. Epidemiology Erdheim-Chester disease is a rare, non-inherited disease of midd...
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État criblé

État criblé, also known as status cribrosum, is a term that describes the diffusely widened perivascular spaces (Virchow-Robin spaces) in the basal ganglia, especially in the corpus striatum on MRI. It is usually symmetrical, with the perivascular spaces showing CSF signal and without diffusion ...
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État lacunaire

État lacunaire is a term describing the presence of multiple lacunar infarcts, which are ischemic strokes due to occlusion of penetrating cerebral arterioles, especially in the basal ganglia. The term has been strongly described as a pathological substrate for a multi-infarct vascular dementia 4...
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Ethylene glycol toxicity

Ethylene glycol toxicity is a type of toxic leukoencephalopathy. Ethylene glycol, best known as a component of antifreeze, has been ingested both deliberately and accidentally, resulting in neurotoxicity and renal failure. Clinical presentation A delay is present between ingestion and developm...
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Evans' index

The Evans' index is the ratio of maximum width of the frontal horns of the lateral ventricles and maximal internal diameter of skull at the same level employed in axial CT and MRI images. This ratio varies with the age and sex. It is useful as a marker of ventricular volume and thus has been pr...
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Exencephaly

Exencephaly is a lethal congenital fetal brain developmental anomaly (neural tube defect) considered to be a precursor to anencephaly in the acrania-exencephaly-anencephaly sequence. Pathology It is characterised by calvarial absence and loss of fetal brain tissue to variable degrees and is co...
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External auditory canal atresia

External auditory canal atresia (EACA) is characterised by complete or incomplete bony atresia of the external auditory canal (EAC) and, especially when seen in the setting of an associated syndrome, a dysplastic auricle and an abnormal middle ear cavity. Epidemiology The incidence is 1 in 10,...
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External capsule

The external capsule is a series of white matter tracts in the brain situated between the putamen and claustrum. It is composed of claustrocortical fibres dorsally and the combined mass of the uncinate fasciculus and inferior frontal occipital fasciculus ventrally.  Relationships The putamen s...
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External petrosal nerve

The external petrosal nerve is one of the three branches from the geniculate ganglion. It carries sympathetic fibers to the middle meningeal artery.
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External ventricular drain

External ventricular drains (EVDs) are a common neurosurgical procedure used to monitor and treat raised intracranial pressure in the acute setting.  Treatment and prognosis Complications infection EVD malfunction EVD malposition intracranial haemorrhage (e.g. subdural, intraventricular) ...
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Extra-axial

Extra-axial is a descriptive term to denote lesions that are external to the brain parenchyma, in contrast to intra-axial which describes lesions within the brain substance.  Radiographic features Often it is trivially easy to distinguish an intra-axial from an extra-axial mass. In many cases,...
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Extra-axial collection (summary)

This is a basic article for medical students and other non-radiologists Extra-axial collections are collections of fluid within the skull, but outside the brain parenchyma. They may be comprised of CSF, blood or pus and may exist in the extradural, subdural or subarachnoid space.  Reference ar...
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Extra-axial masses (differential)

Extra-axial masses of the intracranial compartment have a wide range of differentials, ranging from benign developmental cysts to malignant tumours.  Differential diagnosis neoplasms chordoma choroid plexus papilloma/carcinoma cranial nerve schwannoma meninges meningioma solitary fibrous...
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Extraconal orbital lesions

Extraconal orbital lesions include lesions which arise from structures within the extraconal orbital space and those extending from adjacent structures into the orbits. Differential diagnosis Intraorbital lesions dermoid cyst: most common lesion in paediatrics  lacrimial gland lesions dacry...
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Extracranial brain herniation

Extracranial brain herniation refers to herniation of brain tissue external to the calvaria through a skull bone defect, which may be post-traumatic or post-surgical. Unlike encephaloceles, brain herniation is not surrounded by the meninges.  The herniated brain tissue requires surgical reducti...
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Extracranial meningioma

Extracranial meningiomas, also known as primary extradural meningiomas or ectopic meningioma, are a rare location-specific type of meningioma that arise outside the dural covering of the brain and spinal cord. They are essentially extracranial tumours, most often occurring in the head and neck, ...
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Extradural haematoma vs subdural haematoma

Differentiating extradural (EDH) from subdural (SDH) haemorrhage in the head is usually straightforward, but occasionally it can be challenging. SDHs are more common and there are a few distinguishing features which are usually reliable. Pathology History and mechanism of injury Extradural ha...
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Extradural haemorrhage

Extradural haematoma (EDH), also known as an epidural haematoma, is a collection of blood that forms between the inner surface of the skull and outer layer of the dura, which is called the endosteal layer. They are usually associated with a history of head trauma and frequently associated skull ...
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Extradural haemorrhage (summary)

This is a basic article for medical students and other non-radiologists Extradural haemorrhages (EDH) represent collections of blood in the extradural (epidural) space. The haemorrhage sits between the skull superficially and the dura which overlies the brain parenchyma. Reference article Thi...
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Extradural haemorrhage (venous)

Venous extradural haemorrhages are a relatively uncommon subtype of extradural haemorrhages, differing from arterial extradural haemorrhages not only in aetiology, but also location and prognosis.  They occur as a result of damage to the dural venous sinuses and often result in the displacement...
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Extradural neural axis compartment

Extradural neural axis compartment (EDNAC) exists from the tip of the coccyx all the way to the back of the globe, and yet it is relatively unknown as a concept. It is bounded externally by the periosteum of the vertebrae and sacrum inferiorly and the skull superiorly, and the visceral layer of ...
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Extradural space

The extradural (epidural) space is a potential space between the cranial bones and the endosteal layer of the dura mater, which is otherwise adherent to the cranial bone.  Gross anatomy The extradural space is a potential space inside the cranial vault and is not normally appreciable unless th...
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Extraneural spread of intracranial neoplasm

Extraneural spread of primary intracranial neoplasm is distinctly uncommon, occurring far less frequently than CSF spread.  The most frequent neoplasms to do so, in decreasing order of frequency, are: glioblastoma (GBM) meningioma medulloblastoma
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Extraocular muscle involvement in thyroid associated orbitopathy (mnemonic)

A mnemonic to remember the order in which extraocular muscles are involved in thyroid-associated orbitopathy (TAO) is: I'M SLOw Mnemonic I: inferior rectus M: medial rectus S: superior rectus L: lateral rectus O: obliques There is some debate about this however. Some claim superior rectu...
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Extraocular muscle nerve supply (mnemonic)

A mnemonic to remember the nerve supply to the extraocular muscles: LR6SO4O3 (mock 'chemical formula') Mnemonic The letters represent the extraocular muscles and numbers represent their respective cranial nerve supply: LR6: lateral rectus, innervated by the 6th (abducens) nerve  SO4: superi...
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Extrapontine myelinolysis

Extrapontine myelinolysis (EPM) is one of the complications occurring secondary to rapid correction of hyponatraemia, and is, along with central pontine myelinolysis encompassed by the more recent term osmotic demyelination syndrome. In the vast majority of cases it is associated with central p...
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Extrapulmonary tuberculosis

Extrapulmonary tuberculosis (TB) refers to the haematogenous spread of Mycobacterium tuberculosis. Pathology Extrapulmonary tubercuosis can occur as a primary form of the disease, i.e. direct infection of an extrapulmonary organ without the presence of primary pulmonary tuberculosis or it can ...
Article

Extrapyramidal system

The extrapyramidal system is the part of the motor system involved in modulation and regulation of movement. As its name suggests, it is distinct from the motor fibres that are relayed through the pyramids of the medulla oblongata (corticospinal and corticobulbar tracts). It is composed of nerv...
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Extraventricular neurocytoma

Extraventricular neurocytomas, previously known as cerebral neurocytomas, are rare WHO grade II primary CNS neoplasms usually arising in the cerebral hemispheres. They are, as the name implies, extraventricular versions of central neurocytomas.  Epidemiology These tumours are reported at essen...
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Extreme capsule

The extreme capsule is a series of white matter tracts in the brain that run between the claustrum and insular cortex.
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Eye of the tiger sign (globus pallidus)

The eye of the tiger sign refers to abnormal low T2 signal on MRI (due to abnormal accumulation of iron) in the globus pallidus with a longitudinal stripe of high signal (due to gliosis and spongiosis).  The eye of the tiger sign is most classically associated with pantothenate kinase-associate...
Article

Fabry disease

Fabry disease, also known as Anderson-Fabry disease, is a multisystem disorder resulting from an X-linked inborn error of metabolism. The disease results from genetic mutations which cause decreased or absent expression of hydrolase alpha-galactosidase A, ultimately resulting in abnormal accumul...
Article

Facial-cavernous anastomoses

The facial-cavernous anastomoses are the communications of the facial and deep facial veins with the cavernous sinus. Gross anatomy At the medial canthus of the eye there is a communication with the ophthalmic veins, which drain into the cavernous sinus. Blood from the frontal scalp normally f...
Article

Facial colliculus

The facial colliculus is an elevation on the floor of the fourth ventricle and is not formed by the facial nerve nucleus, but by the fibres of the facial nerve arching backwards around the abducens nerve (CN VI) nucleus before turning forwards once more in the caudal pons. Related pathology A ...
Article

Facial colliculus syndrome

Facial colliculus syndrome refers to a constellation of neurological signs due to a lesion at the facial colliculus, involving: abducens nerve (CN VI) nucleus facial nerve (CN VII) fibres at the genu medial longitudinal fasciculus Clinical presentation lower motor neuron facial nerve palsy ...
Article

Facial nerve

The facial nerve is one of the key cranial nerves with a complex and broad range of functions. Although at first glance it is the motor nerve of facial expression which begins as a trunk and emerges from the parotid gland as five branches (see facial nerve branches mnemonic), it has taste and p...
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Facial nerve branches (mnemonic)

There are many mnemonics to recall the branches of the facial nerve (superior to inferior) as they exit the anterior border of the parotid gland. Examples include: Tall Zulus Bear Many Children Two Zulus Bit My Cat Two Zebras Bit My Coccyx Ten Zebras Buggered My Car To Zanzibar By Motor Car...
Article

Facial nerve choristoma

Facial nerve choristomas are rare, being characterised by non-neoplastic proliferation of smooth muscle cells and fibrous tissue. Facial nerve choristomas presumably can occur anywhere along the course of the facial nerve (CN VII), although the only cases reported are in the internal acoustic me...
Article

Facial nerve schwannoma

Facial nerve schwannoma (FNS), also known as facial nerve neuroma/neurilemoma, is a schwannoma that arises from the facial nerve. They are generally uncommon, and when involving the temporal bone, make up less than 1% of all temporal bone tumours. Epidemiology FNS is a rare tumour 2. Clinical...

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