Articles

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More than 200 results
Article

Hypovitaminosis A

Hypovitaminosis A results from inadequate intake of vitamin A, fat malabsorption, or liver disorders and produces a variety of epithelial alterations. Epidemiology The World Health Organizatiοn estimates that 45-122 countries have a vitamin A deficiency of public health significance based on t...
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Deep cerebral vein thrombosis

Deep cerebral vein thrombosis is a subset of cerebral venous thrombosis involving the internal cerebral veins, often coexisting with cortical vein thrombosis or dural venous sinus thrombosis, and with different clinical presentations relying on which segment is involved. As such please refer to...
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Trochlear nerve

The trochlear nerve is the fourth (CN IV) and thinnest cranial nerve. It exits the midbrain posteriorly, eventually passes into the cavernous sinus and into the orbit where it supplies superior oblique muscle with motor fibres (TA: nervus trochlearis or nervus cranialis IV).  Gross anatomy Nuc...
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Cognard classification of dural arteriovenous fistulas

The Cognard classification of dural arteriovenous fistulas (dAVF) correlates venous drainage patterns with increasingly aggressive neurological clinical course and stratifies the risk of intracerebral haemorrhage. It was first described in 1995 1 and at the time of writing (July 2016) is probabl...
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Spinal cord stimulator

Spinal cord stimulators, also known as dorsal column stimulators, are surgically placed devices intended to provide symptom relief in individuals with chronic neurological pain (e.g. failed back syndrome, brachial plexopathy, complex regional pain syndrome). However, their use remains controver...
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Occipital condyle syndrome

Occipital condyle syndrome describes the concurrence of unilateral occipital pain and ipsilateral hypoglossal nerve palsy, which localises to pathology affecting an occipital condyle. While occipital condyle syndrome can have many potential causes, it nearly always represents a manifestation of ...
Article

Osteolipoma

Osteolipomas, also known as ossified lipomas, are rare intracranial masses, typically located in the suprasellar cistern, composed of mature adipocytes surrounded by calcified ossification 1. They are a variant of intracranial lipomas which rarely have calcification/ossification elsewhere, with ...
Article

Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a rare multisystem disease with a wide and heterogeneous clinical spectrum and variable extent of involvement.  Terminology Langerhans cell histiocytosis was previously known as histiocytosis X. The newer term is preferred as it is more descriptive of its...
Article

Sphincter pupillae muscle

The sphincter pupillae muscle is a circular ring of smooth muscle within the iris responsible for constriction of the pupil (miosis). The structure is stimulated by the parasympathetic nervous system causing the muscle to decrease in diameter as it contracts. Gross anatomy The sphincter pupill...
Article

Intramedullary spinal metastasis

Intramedullary spinal metastases are rare, occurring in ~1% of autopsied cancer patients, and are less common than leptomeningeal metastases. Intramedullary lesions may result from: growth along the Virchow-Robin spaces haematogenous dissemination direct extension from the leptomeninges Epi...
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Cerebral hyperperfusion syndrome

Cerebral hyperperfusion syndrome is a rare complication seen after treatment of long-standing severe carotid stenosis by carotid endarterectomy or carotid artery stenting. It is believed to be the result of failure of normal cerebral blood flow autoregulation.  Terminology Cerebral hyperperfus...
Article

Kissing carotids

The term kissing carotids refers to tortuous and elongated carotid arteries 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 mimi...
Article

Transforaminal epidural steroid injection

Transforaminal epidural steroid injections (TFESI), also known as transforaminal nerve root injections or nerve root blocks, are performed for the treatment and diagnosis of radicular pain. They differ from selective nerve root blocks (SNRB), as the aim is to get an "epidural spill" and get the ...
Article

CSF alpha-fetoprotein

Alpha-fetoprotein (AFP) in the cerebrospinal spinal fluid (CSF) has been reported as a tumour marker for some intracranial tumours with yolk sac elements, and teratoma 1. Interpretation Elevation intracranial yolk sac tumour intracranial embryonal carcinoma congenital CNS tumours with yolk ...
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Gyrus rectus

The gyrus rectus, or straight gyrus, is located at the most medial margin of the inferior surface of the frontal lobe 1,2. Its function is unclear but it may be involved in higher cognitive function (e.g. personality) 3. Gross anatomy The gyrus rectus is bounded medially by the interhemispheri...
Article

Intracranial dermoid cyst

Intracranial dermoid cysts are uncommon lesions with characteristic imaging appearances. Dermoid cysts can be thought of as along the spectrum: from epidermoid cysts at one end (containing only desquamated squamous epithelium) and teratomas at the other (containing essentially any kind of tissue...
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Area postrema

The area postrema, also known as the chemoreceptor trigger zone is one of the so-called circumventricular organs located on the dorsal inferior surface of the medulla oblongata at the caudal end of the fourth ventricle 1. The specialised ependymal cells in the area postrema detect toxins in the...
Article

Shagreen patch

A shagreen patch is a subepidermal collagenous connective tissue naevus, also known as a collagenoma, associated with tuberous sclerosis. The overlying skin may be discoloured with obvious pores, giving the appearance of orange peel. These lesions are most commonly found in the lumbosacral regio...
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Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL)

Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL) is a systemic genetic disorder affecting the cerebral small vessels, spine and hair follicles. CARASIL is an HTRA1-related cerebral small vessel disease, and thus is closely related to, but dis...
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Cerebrovascular malformations

Cerebrovascular malformations are vascular malformations related to the vessels that supply the brain and other cranial structures. Classification Over the years, cerebral vascular malformations have been classified in a variety of ways by many authors, often on the basis of the presence or ab...

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