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.

194 results found
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Abscess

Abscesses are focal confined collections of suppurative inflammatory material and can be thought of as having three components 1: a central core consisting of necrotic inflammatory cells and local tissue peripheral halo of viable neutrophils surrounded by a 'capsule' with dilated blood vessel...
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Absent septum pellucidum

An absent septum pellucidum may rarely be an isolated finding, or more commonly be seen in association with a variety of conditions. Epidemiology The septum pellucidum is partly or entirely absent in 2 or 3 individuals per 100,000 in the general population.  Pathology An absent septum pelluc...
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Acute basilar artery occlusion

Acute occlusion of the basilar artery may cause brainstem or thalamic ischaemia or infarction. It is a true neuro-interventional emergency and, if not treated early, brainstem infarction results in rapid deterioration in the level of consciousness and ultimately death. Epidemiology Occlusions ...
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Acute vs chronic ischaemic stroke

Differentiating between acute and chronic infarction on a CT brain is an important skill for many health professionals particularly in the emergency setting: pathology acute: cytotoxic oedema chronic: encephalomalacia; Wallerian degeneration hypoattenuation acute: more dense than CSF chron...
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Anoxic brain injury

Anoxic brain injury, also known as global hypoxic-ischaemic injury, is seen in all age groups (from antenatal to the elderly) as a result of numerous aetiologies. The pattern of injury depends on a number of factors including: age of the patient (brain maturity) neonatal hypoxic-ischaemic ence...
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Anterior inferior cerebellar artery (AICA) infarct

Anterior inferior cerebellar artery (AICA) territory infarcts are much less common than posterior inferior cerebellar artery (PICA) infarcts. Epidemiology AICA territory infarcts are rare, comprising ~1% of ischaemic cerebellar strokes 2.  Clinical presentation AICA stroke syndrome presents ...
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Artery of Percheron territory infarct

Artery of Percheron territory infarct is rare, on account of the relative rarity of the artery of Percheron, and presents with a variety of signs and symptoms collectively termed the paramedian thalamic syndrome. It is a type of posterior circulation infarction. On imaging, it is classically ch...
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Atlantodental interval

The atlantodental interval (ADI), as the name suggests, is the horizontal distance between the anterior arch of the atlas and the dens of the axis, used in the diagnosis of atlanto-occipital dissociation injuries and injuries of the atlas and axis. It is the distance (in mm) between the posteri...
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Basal ganglia and thalamus signal abnormalities

Basal ganglia and thalamus signal abnormalities occur in a wide variety of conditions. Ischaemia/hypoxia, metabolic disorders and toxins, particularly those that affect the respiratory chain, have a predilection for affecting the basal ganglia as they are highly metabolically active.  They can ...
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Basal ganglia calcification

Basal ganglia calcification is common and is seen in approximately 1% of all CT scans of the brain, depending on the demographics of the scanned population. It is seen more frequently in older patients and is considered a normal incidental and idiopathic finding in an elderly patient but should ...
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Basal ganglia T1 hyperintensity

There are many causes of basal ganglia T1 hyperintensity, but the majority relate to deposition of T1-intense elements within the basal ganglia such as: calcium idiopathic calcification calcium and phosphate abnormalities hepatic failure acquired non-wilsonian hepatocerebral degeneration W...
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Basal ganglia T2 hyperintensity

The causes of basal ganglia T2 hyperintensity can be remembered using the mnemonic LINT: lymphoma ischaemia hypoxia venous infarction (internal cerebral vein thrombosis) neurodegenerative / metabolic Wilson disease Huntington disease: especially caudate heads methylmalonic acidaemia mit...
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Basal ganglia T2 hypointensity

Basal ganglia T2 hypointensities can be caused by any of the following and is commonly remembered using the mnemonic ChOMP. childhood hypoxia old age multiple sclerosis Parkinson disease: more in globus pallidus Parkinson-plus syndrome: more in putamen deoxyhemoglobin of hemorrhage haemos...
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Basilar invagination

Basilar invagination, also called basilar impression, is a congenital or acquired craniocervical junction abnormality where the tip of the odontoid process projects above the foramen magnum.  Terminology The terms basilar invagination and basilar impression are often used interchangeably becau...
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Basion-axial interval

The basion-axial interval (BAI), as the name suggests, is the horizontal distance between the basion and the posterior cortex of the axis, used in the diagnosis of atlanto-occipital dissociation injuries. It is the distance (in mm) between the basion and the superior extension of the posterior ...
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Basion-dens interval

The basion-dens interval (BDI), as the name suggests, is the distance between the basion and the tip of the dens, used in the diagnosis of atlanto-occipital dissociation injuries. It is the distance from the most inferior portion of the basion to the closest point of the superior aspect of the ...
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Benign metastasising tumours

There are a number of benign metastasising tumours: benign metastasising meningioma 1,2 benign metastasising leiomyoma 3 primary adenoma of thyroid 4 giant cell tumour of bone 5
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Bicaudate index

The bicaudate index is the ratio of width of two lateral ventricles at the level of the head of the caudate nucleus to distance between outer tables of skull at the same level. It can be a useful marker of ventricular volume and in the diagnosis of hydrocephalus. 
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Bilateral middle cerebellar peduncle lesions

Involvement of both middle cerebellar peduncles is uncommon, but has a relatively long list of differential diagnoses, including 1: neurodegenerative diseases multiple systemic atrophy (MSA) olivopontocerebellar atrophy Shy-Drager syndrome spinocerebellar atrophy metabolic diseases  adre...
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Birth trauma

Birth trauma relates to those conditions caused by both physical/mechanical and hypoxic injuries. Epidemiology Birth trauma occurs in ~5 per 1000 births 2. Risk factors asphyxia breech presentation shoulder dystocia instrument delivery macrosomia obstructed labour Pathology Aetiology ...
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Brain stone

Brain stones, also known as cerebral calculi, refers to large intracranial calcifications that may be solitary or multiple.  Clinical presentation If symptomatic, patients most commonly present with seizures.  Pathology Localisation of brain stones can help narrow the underlying aetiology bu...
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Calcification of the globe (differential)

Calcification of the globe has many causes, varying from the benign to malignant. When calcification is seen of the posterior half of the globe, it could relate to any of the layers (scleral, choroidal or retinal), as it is not possible to separate them out on CT. Retinal drusen: 1% population...
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Calvarial thickening

Calvarial thickening can occur from a number of causes. These include: idiopathic chronic ventricular shunting1 antiepileptics phenytoin 3 osteopetrosis 2 fibrous dysplasia acromegaly anaemias (largely associated with massive haematopoiesis) Paget disease hyperparathyrodism certain sc...
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Carotid artery stenosis

Carotid artery stenosis also referred as extracranial carotid artery stenosis, is usually caused by an atherosclerotic process and is one of the major causes of stroke and transient ischemic attack (TIA) 1.  This article refers to stenosis involving carotid bulb and the proximal segment of inte...
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Cavernous sinus mass

A cavernous sinus mass has a wide differential including:  meningioma orbital apical inflammation with cavernous sinus involvement (Tolosa-Hunt syndrome) infection  schwannoma  any of the cranial nerves traversing the cavernous sinus: III, IV, V (V1 and V2) and VI trigeminal schwannoma is ...
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Central nervous system curriculum

The central nervous system curriculum is one of our curriculum articles and aims to be a collection of articles that represent the core central nervous system knowledge. Definition  Topics pertaining to the intracranial content (brain, pituitary, dura, intracranial vasculatures). There will be...
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Cerebellopontine angle mass

Cerebellopontine angle (CPA) masses frequently occur, many of which are relatively specific for the region.  Pathology Cerebellopontine angle masses can be divided into four groups, based on imaging characteristics:  enhancing mass mass with high T1 signal on MRI mass with CSF intensity/den...
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Cerebral arteriovenous fistula

Cerebral arteriovenous fistulae (CAVF) are cerebral vascular malformations or acquired conditions in which there is an abnormal direct communication between a venous and an arterial channel without the presence of a true nidus.  dural arteriovenous fistula (DAVF) caroticocavernous fistula (CCF...
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Cerebral atrophy

Cerebral atrophy is the morphological presentation of brain parenchymal volume loss that is frequently seen on cross sectional imaging. Rather than being a primary diagnosis, it is the common endpoint for range disease processes that affect the central nervous system. Though often no identifiabl...
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Cerebral herniation

Cerebral herniation, also referred to as acquired intracranial herniation, refers to shift of cerebral tissue from its normal location, into an adjacent space as a result of mass effect.  Pathology There are a number of different patterns of cerebral herniation which describe the type of herni...
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Cerebral intraparenchymal hyperattenuations post thrombectomy

Cerebral intraparenchymal hyperattenuations have been increasingly recognised on CT scans following mechanical thrombectomy for treatment of thromboembolic ischaemic stroke. It is a term that encompasses both contrast staining and petechial haemorrhagic change, and is used as distinguishing betw...
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Cerebral ring enhancing lesions

The differential for peripheral or ring enhancing cerebral lesions includes: cerebral abscess tuberculoma neurocysticercosis metastasis glioblastoma subacute infarct /haemorrhage /contusion demyelination (incomplete ring) tumefactive demyelinating lesion (incomplete ring) radiation necr...
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Cerebral vascular malformations

Vascular malformations of the central nervous system can be divided, as they can elsewhere, into high and low flow malformations. High flow arteriovenous malformation (AVM) cerebral AVM (pial/parenchymal AVM) cerebral proliferative angiopathy dural arteriovenous fistula (DAVF) pial arteri...
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Cervical spine injury

Cervical spine injuries can involve the cervical vertebral column, intervertebral discs and cervical spine ligaments, and/or cervical spinal cord. The cervical spine accounts for ~50% of all spinal injuries.  Epidemiology 5-10% of patients with blunt trauma have a cervical spine injury 1.  Pa...
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Chamberlain line

Chamberlain line is a line joining the back of hard palate with the opisthion on a lateral view of the craniocervical junction. Significance It helps to recognise basilar invagination which is said to be present if the tip of the dens is >3 mm above this line. McGregor developed a modificatio...
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Chasing the dragon sign (toxic leukoencephalopathy)

Chasing the dragon sign is seen in toxic leukoencephalopathy caused by the inhalation of heroin fumes.  Clinical presentation Three stages are recognised: cerebellar signs and motor restlessness pyramidal and pseudobulbar signs spasms, hypotonic paresis, and ultimately death Only a minorit...
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Chorioretinitis

Chorioretinitis refers to inflammation of the retina and choroid. As a delayed sequelae, it is one of the causes of calcification of the globe. It is often considered a form of posterior uveitis. Pathology Aetiology various congenital infections such as  2,3 rubella: ocular rubella cytomega...
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Christmas inspired signs

There are many signs in radiology that are related to Christmas: snowcap sign in avascular necrosis snowman sign in total anomalous pulmonary venous return in pituitary macroadenomas snowstorm appearance in complete hydatidiform and testicular microlithiasis holly leaf sign in calcified pl...
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Chronic encephalitides

There are several viral and prion infections which can result in a chronic encephalitis with slow progression into brain atrophy. These have very poor prognosis with no effective treatment. Some of these include: progressive multifocal leukoencephalitis subacute sclerosing panencephalitis Ras...
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Clival masses

The differential of a mass involving or arising from the clivus is a relatively narrow one and can be divided into whether the lesion arises from the skull base itself, from the intracranial compartment or from below the base of skull.   When evaluating the clivus it is important to compare the...
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CNS infectious diseases

This article aims to be a collection of articles that represent the central nervous system infectious diseases. There will be some overlap between articles as they are listed and discussed in a mixture of anatomical and aetiological classification.   Terminology It is important to remember tha...
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CNS lymphoma

CNS lymphoma refers to the involvement of the central nervous system with lymphoma. It can be broadly divided into primary and secondary, with a number of special types of also recognised.  primary CNS lymphoma (PCNSL) intravascular lymphoma MALT lymphoma of the dura 5 secondary CNS lymphoma...
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Cochlear implant

Cochlear implants (CI) are a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing. Unlike conventional hearing aids, the cochlear implant does not amplify sound, but works by directly stimulating any functioning audi...
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COL4A1-related disorders

COL4A1-related disorders are a group of autosomal dominant disorders caused by a mutation in the COL4A1 gene. Epidemiology The exact prevalence is unknown, but the group of disorders is considered to be under-recognised, especially asymptomatic variants 1. Clinical presentation The clinical ...
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Colpocephaly

Colpocephaly is a descriptive term to a disproportionate prominence of the occipital horns of the lateral ventricles. It can result from a wide range of congenital insults. Clinical presentation Patient may present with motor abnormalities, cognitive deficit, visual abnormalities, and seizures...
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Communicating hydrocephalus

Communicating hydrocephalus is a type of hydrocephalus where CSF is able to leave the ventricular system.  Terminology Communicating hydrocephalus is commonly used as the opposite of obstructive hydrocephalus which leads to much unnecessary confusion, as most causes of communicating hydrocepha...
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Complications of cranial radiotherapy

Complications of cranial radiation therapy are fairly common, particularly in long-term survivors, and especially in paediatric patients. Cranial radiotherapy is used for a variety of brain tumours, either in isolation or in combination with concurrent chemotherapy. Complications from irradiati...
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Congenital calvarial defects

Congenital calvarial defects are a group of disorders characterised by congenital calvarial bone defects that vary in severity. Radiographic features CT with 3D shaded surface reformats is the best imaging tool as it demonstrates calvarial defects and bone margins: parietal foramina parietal...
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Congenital muscular dystrophies (central nervous system manifestations)

Congenital muscular dystrophies (CMD) are a heterogeneous group of autosomal recessive myopathies presenting at birth with hypotonia, delayed motor development, and early onset of progressive muscle weakness, confirmed with a dystrophic pattern on muscle biopsy.  Clinical presentation There is...
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Congenital syndromes associated with enlarged ventricles

Congenital ventriculomegaly can have a large number of syndromic associations. Common acrocephalosyndactylies Apert syndrome Pfeiffer syndrome acrocephalopolysyndactylies Crouzon syndrome  achondroplasia fetal alcohol syndrome lissencephaly osteopetrosis Sotos syndrome  X-linked hyd...
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Convexal subarachnoid haemorrhage

Convexal subarachnoid haemorrhages (cSAH) are nontraumatic intracranial haemorrhages that occur within the surface sulci of the brain (c.f. basal cisternal distribution of aneurysmal SAH). There are various causes of convexal SAH, some of which include: dural venous sinus thromboses cortical ...
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Coup-contrecoup injury (brain)

A coup-contrecoup injury is a term applied to head injuries and most often cerebral contusions and traumatic subarachnoid haemorrhage. It refers to the common pattern of injury whereby damage is located both at the site of impact (often less marked) and on the opposite side of the head to the po...
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Cranioplasty

Cranioplasty is the surgical intervention to repair cranial defects, and is mostly performed after traumatic injuries. The procedure is performed using different materials and techniques, with no consensus about the best option. Methyl-methacrylate is the prosthetic material most extensively use...
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Craniotomy

Craniotomy is a surgical procedure where a piece of calvarial bone is removed to allow intracranial exposure. The bone flap is replaced at the end of the procedure, usually secured with microplates and screws. If the bone flap is not replaced it is either a craniectomy or cranioplasty.  Classif...
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Cystic spinal lesions

A cystic spinal lesion can result from a number of disease entities. They include: Primary Chiari malformations Dandy walker malformation diastematomyelia spinal dysraphism certain skeletal dysplasias 2 achondroplasia tricho-rhino-phalangeal syndrome type I Acquired due to a tumour as...
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Deep brain stimulation

Deep brain stimulation is used in a variety of clinical settings, predominantly in patients with poorly controlled movement disorders. Although effective, its exact mode of function continues to be poorly understood 2.   Careful patient selection and target selection are essential if the proced...
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Demyelinating disorders

Demyelinating disorders are a subgroup of white matter disorders characterized by the destruction or damage of normally myelinated structures. These disorders may be inflammatory, infective, ischaemic or toxic in origin and include 1-7: autoimmune demyelination multiple sclerosis (MS) Marburg...
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Differential diagnoses for temporal lobe tumours

Most tumours of the CNS can potentially occur in the temporal lobe, but entities with a predilection for being diagnosed in this location include: pleomorphic xanthoastrocytoma (PXA) ganglioneuroma ganglioglioma pilocytic astrocytoma dysembryoplastic neuroepithelial tumour (DNET) multinodu...
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Diffuse cerebellar atrophy

Diffuse atrophy of the cerebellum refers to degeneration/reduction from a previously normal cerebellar volume. Terminology Cerebellar atrophy slightly differs from cerebellar hypoplasia meaning the cerebellum was not well formed to start with. Pathology Aetiology Diffuse atrophy can result ...
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Dopaminergic pathways

Dopaminergic pathways include: mesolimbic  mesocortical  striatonigral  tuberoinfundibular 
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Dural arteriovenous shunts

Dural arteriovenous shunts (DAVS) are rare congenital arteriovenous malformations (CAVMs). On the basis of clinical and anatomical features DAVS have three different types: dural sinus malformations (DSMs) infantile or juvenile DAVS (IDAVS) adult DAVS (ADAVS)
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Dural ectasia

Dural ectasia refers to ballooning or widening of the dural sac which can result in posterior vertebral scalloping and is associated with herniation of nerve root sleeves. Clinical presentation Patients with dural ectasia may present with low back pain or radicular pain in the buttocks or legs...
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Dural enhancement

Pachymeningeal enhancement, also known as dura-arachnoid enhancement 4, refers to a dural and outer layer of arachnoid pattern of enhancement seen following contrast administration and may occur in the conditions listed below: infection intracranial tumour metastases intracranial hypotension...
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Dural masses

Dural masses can be the result of a number of different tumours and conditions, although meningiomas are by far the most common. The differential of a dural mass includes: meningioma haemangiopericytoma primary dural lymphoma Rosai-Dorfman disease solitary fibrous tumour of the dura EBV-as...
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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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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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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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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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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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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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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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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) ...
Article

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 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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Extraneural spread of intracranial neoplasms

Extraneural spread of primary intracranial neoplasms is distinctly uncommon, occurring far less frequently than CSF spread.  The most frequent neoplsams to do so, in decreasing order of frequency are: glioblastoma (GBM) meningioma medulloblastoma
Article

Facial palsy

Facial palsy refers to the neurological syndrome of facial paralysis. It can result from a broad range of physiological insults to the facial nerve or its central nervous system origins. The most common causes of this is Bell palsy.  Terminology While facial palsy refers to the clinical presen...
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Fetal brain tumours

Fetal brain tumours are uncommon and tends to have very different pathological spectrum than that observed in adults; in order of decreasing frequency: fetal intracranial teratoma: most common tumour by far astrocytoma/glioblastoma: next most common craniopharyngioma: papillary type primitiv...
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Fetal intracranial cystic lesions

Fetal intracranial cystic lesions can arise number of pathologies, including: Non-tumourous fetal arachnoid cyst  fetal choroid plexus cyst fetal connatal cyst fetal porencephalic cyst fetal interhemispheric cyst fetal sub ependymal cyst dorsal cyst of holoprosencephaly Blake pouch cyst...
Article

Fetal intracranial haemorrhage

Fetal intracranial haemorrhage may occur either within the cerebral ventricles, subdural space or infratentorial fossa. Pathology Haemorrhages can occur in a number of situations: mechanical trauma, e.g. maternal abdominal blunt or birth trauma severe fetal hypoxia background fetal thromboc...
Article

Fetal ventriculomegaly (differential)

Fetal ventriculomegaly (ventricle width >10 mm) is an important finding in itself and it is also associated with other central nervous system abnormalities. For more information, see the main article fetal ventriculomegaly. Differential diagnosis Fetal ventriculomegaly can be thought of in ter...
Article

Focal calvarial thinning

Focal calvarial thinning can result from a number of causes. They include: bilateral thinning of the parietal bones (normal variant) most common arachnoid cyst mega cisterna magna peripherally located tumors (e.g. oligodendroglioma) See also calvarial thinning calvarial thickening
Article

Fracture-a-la-signature (skull fracture)

Fracture-a-la-signature (or signature fracture) is another term used to described a depressed skull fracture.  Fracture-a-la-signature derives its name from forensic medicine because the size and shape of a depressed skull fracture may give information on the type of weapon used. It can be a si...
Article

Haematomyelia

Haematomyelia refers to the presence of intramedullary haemorrhage or haematoma within the spinal cord. This is distinct from extramedullary haemorrhage, such as that seen in epidural haematomas. Although this can occur in the setting of trauma, the term is generally used to signify non-traumat...
Article

HIV/AIDS (CNS manifestations)

The CNS manifestations of HIV/AIDS (neuroAIDS) occur secondary to a wide range of neurodegenerative, infectious, inflammatory, or neoplastic processes.  Epidemiology Since the introduction of highly active antiretroviral therapy (HAART) in 1996, there has been a shift in the epidemiology of CN...
Article

Hydrocephalus vs atrophy

Accurately determining the cause of ventriculomegaly between hydrocephalus and atrophy (compensatory enlargement of the CSF spaces) can be, at times, challenging in image interpretation. Radiographic features Features that favour hydrocephalus include: dilatation of the temporal horns lack o...
Article

Hyperattenuating cerebral metastases

Hyperattenuating cerebral metastases on CT can be due to haemorrhage, calcium, or highly cellular tumours. Differential diagnosis There is overlap between the entities, with some cerebral metastases appearing in more than one list 1-6:  haemorrhagic cerebral metastases (mnemonic) malignant m...
Article

Hypomyelinating disorders

Hypomyelinating disorders are a subset of white matter disorders characterised by abnormally low amounts of myelination. Clinically, they may be subcategorized into those with and without typical peripheral nervous system involvement (usually determined by nerve conduction studies). These includ...
Article

Hypothalamic lesions

Hypothalamic lesions are numerous representing some entities that are unique to the hypothalamus, as well as many lesions that can be seen elsewhere within the brain. Additionally, due to its proximity to the optic chiasm, third ventricle and pituitary region, many lesions of these locations can...
Article

Hypoxic-ischaemic encephalopathy (adults and children)

Hypoxic-ischaemic encephalopathy in adults and older children (i.e. not neonates), also known as global hypoxic-ischaemic injury, is seen in many settings and often has devastating neurological sequelae. For a discussion of neonatal hypoxia, refer to neonatal hypoxic-ischaemic encephalopathy. ...
Article

IgG4-related disease

IgG4-related disease (IgG4-RD) is a systemic disease that is characterised by extensive IgG4-positive plasma cells and T-lymphocyte infiltration of various organs. Terminology This condition has been known by many other names in the past, such as IgG4-related sclerosing disease, IgG4-related s...
Article

Imaging of gunshot injuries

Gunshot injuries often require imaging assessment, and this evaluation has both clinical relevance (assessment of organ damage, surgical planning and prognostication), and often also forensic implications. Epidemiology Incidence of gunshot injuries to the head is increasing in some countries, ...

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