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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.

2,556 results found
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Subpial hemorrhage

Subpial hemorrhage is a rare form of extra-axial intracranial hemorrhage defined as hemorrhage between the cortical surface and the pia mater. It is an entity that is generally difficult to distinguish from subarachnoid hemorrhage. Epidemiology Subpial hemorrhage has been typically described i...
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Substantia innominata

The substantia innominata (plural: substantiae innominatae), or substantia innominata of Meynert, is an area of mixed grey and white matter located within the anterior perforated substance in the basal forebrain. It contains the acetylcholine-rich basal nucleus of Meynert. Gross anatomy The s...
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Substantia nigra

The substantia nigra is one of the brainstem nuclei and part of the extrapyramidal system. While other nuclei such as the red nucleus are as small and contained within an axial slice at the superior colliculi (see figure), the substantia nigra is seen in axial slices at both superior and inferio...
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Subthalamic nuclei

The subthalamic nuclei are small paired structures that are part of the functional basal ganglia. They are located ventral to the thalamus, dorsal to the substantia nigra and medial to the internal capsule. The subthalamic nucleus receives its main input from the lateral pallidum (external segm...
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Sugar coating

So-called "sugar coating" or zuckerguss (German for sugar icing) refers to the appearance of diffuse linear/sheetlike leptomeningeal contrast enhancement in the brain or spinal cord due to drop metastases or leptomeningeal carcinomatosis. It is seen both as a result of CNS involvement from dista...
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Sulcal effacement

Sulcal effacement is a local secondary sign of mass effect in the cranium. Any lesion exerting mass effect on brain parenchyma can push adjacent gyri together, thereby displacing the CSF from the sulci. It is greatest at the site where the cause of the mass effect is located (e.g. tumor, hemorr...
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Sunburst sign (meningioma)

The sunburst sign refers to the characteristic vascular supply seen in some meningiomas when seen from the side (tangential to the dural attachment). It is the result of the same phenomenon which results in the spoke wheel pattern of vessels (viewed in cross-section, parallel to dural attachment...
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Sunset eye sign

The sunset eye sign (also known as the setting sun phenomenon) is a clinical phenomenon encountered in infants and young children with raised intracranial pressure (seen in up to 40% of children with obstructive hydrocephalus and 13% of children with shunt dysfunction 1).  It consists of an up-...
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Superficial middle cerebral vein

The superficial middle cerebral vein (SMCV) (also known as the Sylvian vein) is one of the superficial cerebral veins. It usually passes along the Sylvian fissure posteroanteriorly, it collects numerous small tributaries which drain the opercular areas around the lateral sulcus. It curves anteri...
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Superficial siderosis

Superficial siderosis is a rare condition which results from the deposition of hemosiderin along the leptomeninges, with eventual neurological dysfunction. On imaging, it is classically characterized on MRI as a rim of low signal coating the surface of the brain or spinal cord, particularly not...
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Superficial veins of the brain

Superficial veins of the brain predominantly drain the cerebral cortex, and include: superior cerebral veins (or superficial cerebral veins) inferior cerebral veins superficial middle cerebral veins superior anastomotic vein (of Trolard) inferior anastomotic vein (of Labbe) Some also inclu...
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Superior anastomotic vein

The superior anastomotic vein (or vein of Trolard) connects the superior sagittal sinus and the superficial middle cerebral vein (of Sylvius). Its size is dictated by the relative size of the superficial middle cerebral vein and the anastomotic vein of Labbé. The vein of Trolard is smaller than...
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Superior cerebellar artery

The superior cerebellar artery (SCA) arises from the distal basilar artery, just below the posterior cerebral artery (PCA) and typically supplies: whole superior surface of the cerebellar hemispheres down to the great horizontal fissure superior vermis dentate nucleus most of the cerebellar ...
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Superior cerebellar artery infarct

Superior cerebellar artery infarcts affect the superior cerebellar hemispheres, cerebellar vermis, and parts of the midbrain. The superior cerebellar artery is the most constantly identified vessel arising from the basilar artery with its origin just below the posterior cerebral artery in the di...
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Superior cerebellar peduncle

The superior cerebellar peduncles (SCP) are paired white matter fiber tracts that connect the cerebellum with the midbrain. The superior cerebellar peduncle contains vital afferent and efferent fibers including cerebellothalamic, cerebellorubral and ventrospinocerebellar tracts. Radiographic fe...
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Superior cerebral veins

The superior cerebral veins drain the superior portion of the cerebral cortex. They run up and medially before draining into the superior sagittal sinus. In a proportion of patients, a large such vein connects the superficial middle cerebral vein to the sinus, and is known as the superior anasto...
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Superior frontal gyrus

The superior frontal gyrus is the medial most gyrus of the frontal lobe's superolateral surface, running from the frontal pole anteriorly, all the way to the precentral sulcus and precentral gyrus posteriorly. Laterally it is bounded by the superior frontal sulcus, which separates it from the m...
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Superior frontal sulcus

The superior frontal sulcus is one of the major sulci of the frontal lobe, separating the superior frontal gyrus medially, from the middle frontal gyrus inferolaterally. It runs posteriorly from the frontal pole, parallel to the interhemispheric fissure, back to the precentral sulcus which it in...
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Superior geniculocalcarine tract

The superior geniculocalcarine tract or superior optic radiation is the posterior/superior fibers of the optic radiation. These superior fibers pass dorsally and posteriorly from the lateral geniculate nucleus through the retrolentiform internal capsule and parietal lobe to the superior margin o...
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Superior hypophyseal artery

The superior hypophyseal artery (or arteries) is a branch from the C6 segment of the internal carotid artery. It is usually a single trunk arising from the medial or posteromedial aspect of the internal carotid artery within 5 mm of the origin of the ophthalmic artery 2. The trunk then divides i...
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Superior medullary velum

The superior (or anterior) medullary velum is a thin layer of tissue that is suspended between the superior cerebellar peduncles forming the roof of the fourth ventricle along with the inferior medullary velum. It is enclosed by pia mater dorsally and ependyma ventrally. The lingula of the vermi...
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Superior occipital sulcus

The superior occipital sulcus is a sulcus of the occipital lobe that separates the superior from the middle occipital gyri. It is usually seen as a posterior continuation of the intraparietal sulcus.
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Superior olivary nucleus

The superior olivary nuclei (or complex, SOC) are a group of nuclei within the pons contributing to the ascending and descending auditory pathways. Gross anatomy The superior olivary nuclei are located in the pons, while the inferior olivary nuclei are located in the medulla. It is generally s...
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Superior ophthalmic vein

The superior ophthalmic vein is a prominent vein of the orbit that is seen on CT and may be enlarged or tortuous in various disease entities. Gross anatomy Origin Formed in the anterior part of the orbit by the union of the angular, supraorbital and supratrochlear veins. Course courses late...
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Superior orbital fissure

The superior orbital fissure is the communication between the cavernous sinus and the apex of the orbit. It is straddled by the tendinous ring which is the common origin of the four rectus muscles (extraocular muscles). Gross anatomy Boundaries medial: body of sphenoid superior: lesser wing ...
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Superior orbital fissure (mnemonic)

Mnemonic for all structures passing through the superior orbital fissure (superior to inferior) include: Long Fissures Seem To Store Only Nerves, Instead Of Arteries, Including Ophthalmic Veins Mnemonics for the nerves passing through the superior orbital fissure include: Lazy French Tarts Si...
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Superior orbital fissure syndrome

Superior orbital fissure syndrome (SOFS) (also known as Rochon–Duvigneaud syndrome) is a rare complication of craniofacial trauma with an orbital fracture that extends to the superior orbital fissure that results in injury to the cranial nerves III, IV, V (ophthalmic branch of the trigeminal ner...
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Superior parietal lobule

The superior parietal lobule is one of the three subdivisions of the parietal lobe. The other subdivisions include the inferior parietal lobule and postcentral gyrus. It is involved with sensorimotor integration 1. Gross anatomy Relations It is separated from the inferior parietal lobule by t...
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Superior petrosal sinus

The superior petrosal sinus is one of the dural venous sinuses and drains the cavernous sinus, posterolaterally to the transverse sinus. It runs along the superior aspect of the petrous temporal bone. It receives: cerebellar veins inferior cerebral veins labyrinthine vein: draining the inner ...
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Superior sagittal sinus

The superior sagittal sinus (SSS) is the largest dural venous sinus. As the name suggests, it runs in a sagittal plane from the anterior aspect of the falx cerebri at the foramen cecum to its termination at the confluence of sinuses at the occipital protuberance, where it usually proceeds rightw...
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Superior sagittal sinus thrombosis

Superior sagittal sinus thrombosis (SSST) is the most common type of dural venous sinus thrombosis and is potentially devastating. This article focuses on the specific features related to the superior sagittal sinus thrombosis, please refer to the dural venous sinus thrombosis article for a gen...
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Superior salivary nucleus

The superior salivary nucleus of the facial nerve is a visceromotor parasympathetic cranial nerve nucleus located in the pontine tegmentum.
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Superior temporal gyrus

The superior temporal gyrus forms the most superior part of the temporal lobe, and has a role in both verbal and non-verbal communication.  Gross anatomy The superior temporal gyrus is situated at the topmost aspect of the temporal lobe, lying inferior to the lateral sulcus and superior to the...
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Superior temporal sulcus

The superior temporal sulcus runs longitudinally along the lateral surface of the temporal lobe, parallel to the Sylvian fissure above and the inferior temporal sulcus below. It separates the superior temporal gyrus from the middle temporal gyrus.  Posteriorly it is capped by the angular gyrus. 
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Supplementary motor area

The supplementary motor area (SMA) is involved in preparing for voluntary movements carried out by the primary motor area (precentral gyrus). It is located on the medial surface of the frontal lobe, contained posteriorly within the medial surface superior frontal gyrus (sometimes referred to as ...
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Supramarginal gyrus

The supramarginal gyrus is a portion of the parietal lobe of the brain. It is one of the two parts of the inferior parietal lobule, the other being the angular gyrus. It plays a role in phonological processing and emotional responses. Gross anatomy Relations The supramarginal gyrus is horsesh...
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Supraoptic commissure

The supraoptic commissure consists of: Gudden commissure Meynert commissure Gasner commissure
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Supraoptic nucleus

The supraoptic nucleus (SON) contains neurosecretory cells that produce hormones (oxytocin and vasopressin/antidiuretic hormone).  Gross anatomy The supraoptic nucleus is found in the medial area of the anterior hypothalamus, sitting superior to the optic tract 1. The hormones travel down the...
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Supraoptic recess

The supraoptic recess, also known as the optic recess or chiasmatic recess, is a small angular recess or diverticulum that sits at the junction of the floor and anterior wall of the third ventricle, immediately above the optic chiasm. Related pathology When the third ventricle is expanded due ...
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Suprapineal recess

The suprapineal recess is a small angular recess or diverticulum that forms the posterior wall of the third ventricle superior to the habenular commissure and the larger pineal recess. Some anatomists describe a single pineal recess rather than separate pineal and suprapineal recesses.
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Suprasellar arachnoid cyst

Suprasellar arachnoid cysts can be challenging to diagnose and, unlike many other arachnoid cysts, are usually symptomatic.  For a general discussion, please refer to the article on arachnoid cysts. Clinical presentation As can be expected from its location, suprasellar arachnoid cysts manife...
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Suprasellar cistern

The suprasellar cistern (also known as the chiasmatic cistern or pentagon of basal cisterns) is a cerebrospinal fluid-filled cistern located above the sella turcica, under the hypothalamus and between the uncus of the temporal lobes. It contains the proximal part of Sylvian fissure,  the optic c...
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Suprasellar cistern lipoma

Suprasellar cistern lipomas are uncommon, usually incidental findings, with characteristic imaging features and very limited differential diagnosis. A proportion of these lesions can peripherally ossify, in which case they are referred to as osteolipomas 4.  For a general discussion of intracra...
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Suprasellar cystic lesions

The differential for suprasellar cystic lesions is large and predominantly includes developmental and neoplastic conditions. Differential diagnosis Developmental arachnoid cyst craniopharyngioma Rathke's cleft cyst dermoid cyst epidermoid cyst ependymal cyst enlarged perivascular spaces...
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Supratentorial ependymoma

Supratentorial ependymomas are a type of location-specific ependymoma. They account for 30% of ependymomas, and in most instances are within or abutting the ventricles (third and fourth ventricles). In approximately 40% of cases they are remote from the ventricular surface, located within the pa...
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Supratentorial intracranial mass in an adult (an approach)

The identification of a supratentorial intracranial mass in an adult is a fairly common clinical scenario, the appropriate management of which relies heavily on preoperative imaging. Often important clues will be present in the clinical history (e.g. immunosuppression, systemic malignancy, durat...
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Surgical positions

There are various classic surgical positions for patients to be placed in for procedures, which have been adopted/repurposed for interventional radiology and some diagnostic procedures: lithotomy position Trendelenburg position reverse Trendelenburg position lateral decubitus position Litho...
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Susac syndrome

Susac syndrome (SS), also known as SICRET syndrome (small infarctions of cochlear, retinal and encephalic tissue), is a rare syndrome typically affecting young to middle-age women that is clinically characterized by the triad of acute or subacute encephalopathy, bilateral sensorineural hearing l...
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Susceptibility weighted imaging

Susceptibility weighted imaging (SWI) is an MRI sequence that is particularly sensitive to compounds which distort the local magnetic field and as such make it useful in detecting blood products, calcium, etc. Physics SWI is a 3D high-spatial-resolution fully velocity corrected gradient-echo M...
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Suspected physical abuse

Suspected physical abuse (SPA), also known as non-accidental injury (NAI) or inflicted injury, in infants and young children represents both ethical and legal challenges to treating physicians. Radiologists may be the first clinical staff to suspect non-accidental injuries when confronted with ...
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Sutural diastasis

Sutural diastasis is an abnormal widening of the skull sutures. It may be physiological in a neonate during a growth spurt.  Pathology In non-traumatic scenarios accelerated growth of the sutural connective tissue without concurrent ossification is the underlying pathology.  Etiology traumat...
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Sutures

There are many sutures of the skull, which are where skull bones meet. In general, sutures don't fuse until brain growth is complete, therefore allowing the skull to increase in size with the developing brain. Gross anatomy Sutures are fibrous joints with the periosteum externally and outer la...
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Suzuki staging system for Moyamoya

The staging system for moyamoya disease first described by Suzuki and Takaku in their seminal 1969 article 1 is still in use today. Formally, the staging refers to findings on conventional angiography, although there are efforts to apply similar systems to MR angiography 2. Suzuki stage appears...
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Swallow tail sign (substantia nigra)

The swallow tail sign describes the normal axial imaging appearance of nigrosome-1 within the substantia nigra on high-resolution T2*/SWI weighted MRI. Terminology Yes, this is one of those annoying signs where its presence is normal. A normal-appearing substantial nigra is reminiscent of a sw...
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Swirl sign (intracranial hemorrhage)

The swirl sign refers to the non-contrast CT appearance of acute extravasation of blood into a hematoma, for example an intracerebral hemorrhage, extradural hematoma or subdural hematoma. It represents unclotted fresh blood which is of lower attenuation than the clotted blood which surrounds it ...
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Sylvian cistern

The Sylvian cistern, also known as the insular cistern, is one of the CSF-filled subarachnoid cisterns. Gross anatomy There are two paired cisterns on either side. It is the transitional subarachnoid space between the rest of the basal cisterns and the Sylvian fissure (lateral sulcus) 2. Boun...
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Sylvian fissure

The Sylvian fissure, also known as the lateral sulcus, separates the frontal and parietal lobes superiorly from the temporal lobe inferiorly. The insular cortex is located immediately deep to the Sylvian fissure.  Anteriorly the fissure courses medially to form the 'stem' of the lateral fissure...
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Sympathetic chain

The sympathetic chain is a component of the autonomic nervous system and is composed of general visceral afferent and efferent axons that allow for involuntary control of bodily functions via the hypothalamus. The overarching function of the sympathetic system is to control the 'fight, fright o...
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Syndrome of the trigone

Syndrome of the trigone occurs when intracranial tumors that arise in the trigone of the lateral ventricle present with a distinctive constellation of signs and symptoms due to compression of the posterior limb of the internal capsule and the adjacent white matter of the parietal and posterior f...
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Syntelencephaly

Syntelencephaly, also known as middle interhemispheric variant (MIHV), is a mild subtype of holoprosencephaly that is characterized by an abnormal midline connection of the cerebral hemispheres between the posterior frontal and parietal regions.  Epidemiology Syntelencephaly is a congenital ma...
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Synucleinopathy

Synucleinopathies are a subgroup of neurodegenerative diseases, characterized by impairment of alpha-synuclein metabolism, resulting in abnormal intracellular deposits and can further be divided into those with and those without the formation of Lewy bodies 1,2: synucleinopathies with Lewy bodi...
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Syphilis

Syphilis is the result of infection with the gram negative spirochete Treponema pallidum, subspecies pallidum. It results in a heterogeneous spectrum of disease with many systems that can potentially be involved, which are discussed separately.  Epidemiology Despite the discovery of penicillin...
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Syringobulbia

Syringobulbia is a rare entity and refers to a syrinx that extends into the medulla oblongata 1. Terminology Some authors use syringobulbia to refer to a syrinx present in any portion of the brainstem rather than specifically involving the medulla oblongata, and therefore encompassing syringop...
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Syringocephalus

Syringocephalus , also known as syringoencephalomyelia, is a very rare entity and refers to a syrinx that extends into the cerebrum 1. Clinical presentation Patients with this condition demonstrate a wide variety of focal neurological symptoms depending on where the syrinx is located 1. Patho...
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Syringomesencephaly

Syringomesencephaly is a very rare entity and refers to a syrinx that extends into the midbrain 1. Clinical presentation Patients with this condition demonstrate a wide variety of neurological symptoms localized to the brainstem and spinal cord, depending on where exactly the syrinx is located...
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Syringomyelia

Syringomyelia refers to a cystic collection, or syrinx, that occurs within the spinal cord around the central canal.  Terminology Although syringomyelia is distinct from hydromyelia, in which there is simply dilatation of the central canal, it is very difficult to distinguish the two on imagin...
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Syringopontia

Syringopontia is a rare entity and refers to a syrinx that extends into the pons 1. Clinical presentation Patients with this condition demonstrate a wide variety of neurological symptoms localized to the pons, medulla oblongata, and spinal cord, depending on where exactly the syrinx is located...
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Syrinx

Syrinx is the collective name given to hydromyelia, syringomyelia, syringobulbia, syringopontia, syringomesencephaly, and syringocephalus. Terminology The use of the general term 'syrinx' has grown out of the difficulty in distinguishing between hydromyelia and syringomyelia using current imag...
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Syrinx terminology

There are specific terms used when describing a syrinx or other cystic lesions within the spinal cord 1: hydromyelia: fluid accumulation/dilatation within the central canal, therefore, lined by ependyma syringomyelia: cavitary lesion within cord parenchyma, of any cause (there are many); locat...
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Systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disease with multisystem involvement. Although abnormalities in almost every aspect of the immune system have been found, the key defect is thought to result from a loss of self-tolerance to autoantigens. Epidemiology There is a strong...
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Systemic lupus erythematosus (CNS manifestations)

Central nervous system manifestations of systemic lupus erythematosus (CNS lupus) describe a wide variety of neuropsychiatric manifestations that are secondary to systemic lupus erythematosus (SLE) in the central nervous system (CNS). For a general discussion, and for links to other system spec...
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T1 black holes

T1 black holes are hypointense lesions commonly seen on T1WI in patients with multiple sclerosis, and indicates the chronic stage with white matter destruction, axonal loss and irreversible clinical outcome. There is a correlation between the number of black holes and patient positive outcome 3.
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T2 blackout effect

T2 blackout effect is a diffusion weighted imaging phenomenon, representing the reverse of T2 shine through. The 'true' diffusion signal (as determined by ADC values) is reduced on DWI images (e.g. B=1000) by the presence of very low T2 signal (on B=0 images). 
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T2-FLAIR mismatch sign

The T2-FLAIR mismatch sign describes the MRI appearance considered highly specific for diffuse or anaplastic astrocytoma (IDH-mutant, 1p/19q-non-codeleted molecular status) as opposed to other lower grade gliomas. On T2WI, the tumor has homogeneously high signal intensity. On T2-FLAIR, the major...
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T2 hyperintense basal ganglia (mnemonic)

A helpful mnemonic to recall the causes of T2 hyperintense basal ganglia is: LINT Mnemonic L: lymphoma I: ischemia N: neurodegenerative conditions T: toxins See also For a more detailed differential please see T2 hyperintense basal ganglia article. 
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T2 hypointense basal ganglia (mnemonic)

The commonest causes of basal ganglia T2 hypointensity can be recalled using the following mnemonic: ChOMP Mnemonic Ch: childhood hypoxia O: old age M: multiple sclerosis P: Parkinson's disease, more in globus pallidus
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T2 shine through

T2 shine-through refers to high signal on DWI images that is not due to restricted diffusion, but rather to high T2 signal which 'shines through' to the DWI image. T2 shine through occurs because of long T2 decay time in some normal tissue. This is most often seen with subacute infarctions due ...
Article

T2 washout

T2 washout is a phenomenon encountered on diffusion weighted imaging (DWI) which results in DWI images (e.g. B = 1000) appearing normal despite abnormal ADC maps.  For the phenomenon to occur a particular combination of ADC and T2 signal intensity is required.  increased T2 signal facilitated...
Article

Tabes dorsalis

Tabes dorsalis is a form of tertiary late neurosyphilis in which there is demyelination of the posterior columns of the spinal cord. For a general discussion, and for links to other system specific manifestations, please refer to the article on syphilis.  Clinical presentation Patients presen...
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Tadpole sign

The tadpole sign, also known as the lollipop sign, refers to a characteristic morphology of post-traumatic bridging vein thrombosis with a rounded "head" and a tapering "tail". The finding demonstrates a high specificity for abusive head trauma, a sub-type of non-accidental injury, and should wa...
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Tail sign

The tail sign has been described as being specific to Dandy-Walker malformation in fetal MRI.1 It is described as a linear T2 hypointensity in the inferior part of the vermis. Histologically, it corresponds to a thickness of the fourth ventricle roof that appears raised and dysplastic.1 The sp...
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Tam o' shanter sign (skull)

The "tam o' shanter" is a Scottish hat, named after the character in Robert Burns' 1 poem of the same name. The appearances of advanced Paget disease of the skull are similar in appearance to the hat.  Paget involvement of the skull, with widening of the diploic space and an overall enlargement...
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Tanycytes

Tanycytes are one of the three types of ependymal cells, themselves a type of glial cell. They are found lining the floor of the third ventricle overlying the median eminence of the hypothalamus 1.   It is believed that these specialized cells are involved in the feedback mechanisms on the ante...
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Tanycytic ependymoma

Tanycytic ependymomas are histological variants of ependymomas, usually found in the spinal cord 1. Their name reflects the morphological similarlity of these tumor cells to the tanycytes. They do not arise from tanycytes which are located primarily in the floor of the third ventricle. 
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Target sign (peripheral nerve sheath tumor)

The target sign of peripheral nerve sheath tumor (PNST) is a lesional pattern of T2 signal on MRI consisting of a central area of low intensity surrounded by a T2 hyperintense rim. It is most commonly associated with localized neurofibroma, having been shown to correspond histopathologically wit...
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Target sign (tuberculosis)

The target sign of tuberculosis refers to the bull's eye appearance of some parenchymal tuberculomas involving the brain (see: CNS tuberculosis) and solid abdominal organs (see: hepatic and splenic tuberculosis) on cross-sectional imaging.  Radiographic features Ultrasound hypoechoic nodules ...
Article

Tarlov cyst

Tarlov cysts, also called perineural cysts, are CSF-filled dilatations of the nerve root sheath at the dorsal root ganglion (posterior nerve root sheath). These are type II spinal meningeal cysts that are, by definition, extradural but contain neural tissue. Most Tarlov cysts are asymptomatic, ...
Article

Tauopathy

Tauopathies are a heterogeneous group of neurodegenerative diseases characterized by abnormal metabolism of misfolded τ (tau) proteins leading to intracellular accumulation and formation of neurofibrillary tangles (NFT). These neurofibrillary tangles are deposited in the cytosol of neurons and g...
Article

Tau sign

The tau sign represents the appearance of a persistent primitive trigeminal artery on the sagittal plane of an angiogram or on sagittal MRI images. It resembles the Greek letter τ, pronounced 'tau', and is equivalent to the modern day 'T' in the Latin alphabet. The persistent trigeminal artery ...
Article

Taylor dysplasia

Taylor dysplasia is a type of focal cortical dysplasia and a common cause of refractory epilepsy. Under both the Palmini classification and the more recent Blumcke classification of focal cortical dysplasia, Taylor dysplasia is classified as type II.  For further discussion of the radiographic ...
Article

Tay-Sachs disease

Tay-Sachs disease is a hereditary neurodegenerative disorder resulting from excess storage of GM2 ganglioside within the lysosomes of cells.  Epidemiology The incidence of the disease is estimated to be 1 in 3600 in Ashkenazi Jews with a carrier frequency of 1 in 30 and 1 in 360,000 in other p...
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TDP-43 proteinopathy

The TDP-43 proteinopathies are a set of neurodegenerative disorders characterized pathologically by cytoplasmic inclusions composed of TDP-43. The pathology has been implicated in three major diseases: amyotrophic lateral sclerosis (vast majority of cases) frontotemporal lobar degeneration (sl...
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Technetium agents

Technetium agents based on the technetium-99m (Tc-99m) radioisotope are frequently used agents in medical imaging. A radiopharmaceutical labeled with 99mTc constitutes a coordination complex in which ligands bond to a central atom of 99mTc by coordinate covalent bonds 4 . The radioactive techne...

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