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.

2,384 results found
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Sickle cell disease

Sickle cell disease (SCD) (historically known as drepanocytosis) is a hereditary (autosomal recessive) condition resulting in the formation of abnormal hemoglobin (a hemoglobinopathy), which manifests as multisystem ischemia and infarction, as well as hemolytic anemia.  Hemoglobin SC (HbSC) dis...
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Phthisis bulbi

Phthisis bulbi, also known as end-stage eye, is an atrophic scarred and disorganized globe that may result from a variety of severe ocular insults.  Epidemiology In general, phthisis bulbi involves elderly patients, usually 65-85 years of age 7. Children and adolescents are only rarely affecte...
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Methyl methacrylate cranial prosthesis

A methyl methacrylate cranial prosthesis is of heterogeneous density, similar to muscle, and contains locules of gas. The most common cause of a bony defect is trauma, and repair of the defect is called a cranioplasty. The methyl methacrylate is the monomer form of the final plastic material, t...
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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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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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Krabbe disease

Krabbe disease, also known as globoid cell leukodystrophy, is an autosomal recessive lysosomal storage disorder resulting in damage to cells involved in myelin turnover. It thus affects both the peripheral nervous system and central nervous system (manifesting as a leukodystrophy).  Epidemiolog...
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Fucosidosis

Fucosidosis (plural: fucosidoses) is a rare inherited autosomal recessive lysosomal storage disorder, hypomyelinating disorder, and mucopolysaccharidosis-like disorder, characterized by multiorgan accumulation of fucose-containing products. Epidemiology It is considered very rare, with approxi...
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Fabry disease

Fabry disease, also known as Anderson-Fabry disease, is a multisystem disorder resulting from an X-linked inborn error of metabolism, and is a lysosomal storage disorder. The disease results from genetic mutations which cause decreased or absent expression of hydrolase alpha-galactosidase A, ult...
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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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Langerhans cell histiocytosis (CNS manifestations)

The central nervous system (CNS) is an uncommonly involved organ system in Langerhans cell histiocytosis (LCH). Involvement of the CNS is related but distinct from involvement of the skull base or craniofacial structures, which are discussed separately in the article skeletal manifestations of L...
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Meningioma

Meningiomas are extra-axial tumors and represent the most common tumor of the meninges. They are a non-glial neoplasm that originates from the meningocytes or arachnoid cap cells of the meninges and are located anywhere that meninges are found, and in some places where only rest cells are presum...
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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 recognized...
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Pituitary metastasis

Pituitary metastases are rare, and unless a systemic metastatic disease is already apparent, are often preoperatively misdiagnosed as pituitary adenomas.  This article will discuss metastatic lesions affecting only the pituitary gland. For other intracranial metastatic locations, please refer t...
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Pituitary stone

Pituitary stones, also known as pituitary lithiases or pituitary calculi, are very rare types of brain stones characterized by extensive calcifcation in the sella turcica. Terminology Throughout the literature, there is contention and inconsistency regarding what pituitary stones actually are....
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Neurosarcoidosis

Central nervous system involvement by sarcoidosis, also termed neurosarcoidosis, is relatively common among patients with systemic sarcoidosis and has a bewildering variety of manifestations, often making diagnosis difficult.  For a general discussion of the underlying condition, please refer t...
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POEMS syndrome

POEMS syndrome is the acronymic name for a rare multisystem paraneoplastic disorder comprising of a minimum of three of the following features in the setting of a plasma cell dyscrasia: P: polyneuropathy O: organomegaly hepatomegaly, splenomegaly or lymphadenopathy E: endocrinopathy diabete...
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Pyrexia

Pyrexia (or fever) is a clinical sign, indicated by an abnormally elevated core body temperature, which is defined by several medical societies as ≥38.3°C. The temperature elevation may be persistent or episodic. The commonest cause of fever is infection, in one study of hospital inpatients acco...
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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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High-velocity penetrating brain injury

High-velocity penetrating brain injuries, in practical terms most often due to cranial gunshot injuries, are a form of penetrating traumatic brain injuries, which are much less common than blunt traumatic brain injuries and distinguished from low-velocity penetrating brain injuries (such as stab...
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Lacunar infarct

Lacunar infarcts are small (<15 mm) infarcts in the distal distribution of deep penetrating vessels (lenticulostriate, thalamoperforating, and pontine perforating arteries, recurrent artery of Heubner). They result from occlusion of one of the small penetrating end arteries at the base of the br...
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Typhoid fever

Typhoid fever or just typhoid is an infectious disease caused by the Salmonella enterica serovar Typhi bacterium, usually spread by the orofecal route. The condition is characterized by severe fever, acute systemic symptoms, with occasionally serious enterocolic complications. Terminology Do n...
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Traumatic subarachnoid hemorrhage

Traumatic subarachnoid hemorrhage (tSAH) is a common injury, and trauma is the most common cause of subarachnoid hemorrhage (SAH).  Epidemiology Traumatic subarachnoid hemorrhage occurs in ~35% (range 11-60%) of traumatic brain injuries 1.  Pathology Traumatic subarachnoid hemorrhage is more...
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Oligodendroglioma

Oligodendrogliomas are intracranial tumors that account for 5-25% of all gliomas and 5-10% of all primary intracranial neoplasms. On imaging, oligodendrogliomas commonly present as masses involving the cortex or subcortical white matter, with low attenuation on CT, hypointense compared to grey ...
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Pilocytic astrocytoma

Pilocytic astrocytomas, also known as juvenile pilocytic astrocytomas, are low-grade, relatively well-defined astrocytomas that tend to occur in young patients. They are considered WHO grade I tumors in the current (2016) WHO classification of CNS tumors and correspondingly have a relatively goo...
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Hunt and Hess grading system

The Hunt and Hess scale describes the severity of subarachnoid hemorrhage, and is used as a predictor of survival. grade 1 asymptomatic or minimal headache and slight neck stiffness 70% survival grade 2 moderate to severe headache; neck stiffness; no neurologic deficit except cranial nerve ...
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Subdural hygroma

Subdural hygromas refer to the accumulation of fluid in the subdural space. In many cases, it is considered an epiphenomenon of head injury when it is called a traumatic subdural hygroma.  Epidemiology Subdural hygromas are encountered in all age-groups but are overall most common in the elder...
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Familial multiple cavernous malformation syndrome

Familial multiple cavernous malformation syndrome is uncommon, accounting for only a minority of cavernous malformations. Epidemiology It has been more frequently reported in patients of Hispanic descent 1. Clinical presentation The presentation is most commonly with seizures (38-55%) 1 and ...
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Harlequin eye deformity

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

The leukodystrophies are a heterogeneous group of disorders that primarily affect the white matter of the central nervous system. They are particularly encountered in childhood as many are genetically determined and represent abnormalities in white matter metabolism. A number of leukodystrophies...
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Cerebral cavernous venous malformation

Cerebral cavernous venous malformations, commonly known as cavernous hemangioma or cavernoma, are common cerebral vascular malformations, usually with characteristic appearances on MRI.  Cavernous malformations are found throughout the body. This article focuses on cerebral cavernous venous mal...
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Modified Fisher scale

The modified Fisher scale is a method for grading subarachnoid hemorrhage (SAH) secondary to intracranial aneurysm rupture, seen on non-contrast CT. It was developed from the original Fisher scale which was modified to account for patients with thick cisternal blood and concomitant intraventricu...
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Subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a type of extra-axial intracranial hemorrhage and denotes the presence of blood within the subarachnoid space. Epidemiology Patients tend to be older middle age, typically less than 60 years old 2. Subarachnoid hemorrhage accounts for 3% of stroke and 5% of str...
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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...
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Hemorrhage on MRI

Hemorrhage on MRI has highly variable imaging characteristics that depend on both the age of the blood, the type of hemoglobin present (oxy- deoxy- or met-), on whether or not the red blood cell walls are intact and the specifics of the MRI sequence. Although MRI is often thought of as not being...
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Extradural hemorrhage

Extradural hematoma (EDH), also known as an epidural hematoma, 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 fr...
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Plagiocephaly

Plagiocephaly refers to a type of craniosynostosis in which there is asymmetric premature closure of the coronal and/or lambdoid sutures. It can either involve single or asymmetric multiple sutures. Premature coronal suture closure is associated with the Harlequin eye deformity. History and ety...
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Posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic state that occurs secondary to the inability of the posterior circulation to autoregulate in response to acute changes in blood pressure. Hyperperfusion with resultant disruption of the blood brain barrier results in vasogenic e...
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Choroidal fissure cyst

Choroidal fissure cysts, also known as choroid fissure cysts, are benign intracranial cysts occurring within the choroidal fissure. They are therefore a location-based diagnosis rather than a distinct pathological entity. Clinical presentation They are usually asymptomatic and discovered incid...
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Tuberculous meningitis

Tuberculous meningitis is the most common presentation of intracranial tuberculosis, and usually refers to infection of the leptomeninges. Uncommonly tuberculosis can be limited to the pachymeninges (dura mater), it is called tuberculous pachymeningitis and is discussed separately.  The remaind...
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Bilateral thalamic glioma

Bilateral thalamic gliomas are rare but characteristic low-grade astrocytomas that occur in both children and young adults. Clinical presentation Presentation may vary with age. Young children with bilateral thalamic glioma often have signs of increased intracranial pressure and movement disor...
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Posterior choroidal artery

The posterior choroidal artery is not in fact a single artery, although it is commonly referred to as such. The posterior choroidal arteries, often numbering up to 10 or 11 per hemisphere, are divided into medial posterior choroidal artery and lateral posterior choroidal artery groups. They usua...
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Lytic skull lesion

Lytic skull lesions have a relatively wide differential that can be narrowed, by considering if there are more than one lesion and whether the mandible is involved. Pathology Causes lytic skeletal metastases multiple myeloma epidermoid - scalloped border with a sclerotic rim eosinophilic g...
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Saethre-Chotzen syndrome

Saethre-Chotzen syndrome (also known as type III acrocephalosyndactyly) is characterized by limb and skull abnormalities. Epidemiology It is the most common craniosynostosis syndrome and affects 1:25 - 50,000 individuals. Males and females are equally affected. Clinical presentation The spe...
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Functional MRI

Functional magnetic resonance imaging (fMRI) is a technique used to obtain functional information by visualizing cortical activity. fMRI detects subtle alteration in blood flow in response to stimuli or actions. It is used in two broad ways: clinical practice typically in presurgical patients ...
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Technetium agents

Technetium agents based on the technetium-99m (Tc-99m) radioisotope are frequently used agents in medical imaging. The radioactive technetium radiotracer can be chelated to a number of different compounds to create specific radiopharmaceuticals and optimize the functional imaging of various stru...
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Fibromuscular dysplasia

Fibromuscular dysplasia (FMD) is a heterogeneous group of vascular lesions characterized by an idiopathic, non-inflammatory, and non-atherosclerotic angiopathy of small and medium-sized arteries. Epidemiology The prevalence is unknown 7. It is most common in young women with a female to male r...
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Alport syndrome

Alport syndrome is an X-linked dominant disease characterized by progressive sensorineural hearing loss, renal disease and, at times, ocular lesions. Clinical presentation hematuria sensorineural hearing loss: typically high frequency 2 ocular abnormalities anterior lenticonus: most common ...
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Indication for neuroimaging in new onset seizures

Neuroimaging in new onset seizures is recommended for all patients, even with a return to baseline neurological status. This is specifically recommended in the context of: new focal deficits persistent altered mental status fever trauma persistent headache cancer history anticoagulation ...
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Intracranial choriocarcinoma

Intracranial choriocarcinomas are rare, accounting for only 5% of all pineal masses 2 and 10% of all intracranial germ cells tumors 1. Like other intracranial germ cell tumors, they are found both in the pineal and suprasellar region. Typically they have increased CSF and plasma b-HCG, which are...
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Brainstem nuclei

The brainstem nuclei are the nuclei in the brainstem. These include: cranial nerve nuclei red nucleus substantia nigra
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Calcarine artery

The calcarine artery, named according to its course in the calcarine fissure, is a branch of the posterior cerebral artery, usually from the P3 segment. It may also arise from the parieto-occipital artery or posterior temporal branches. It courses deep in the fissure, giving branches both to the...
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Puff of smoke sign

The puff of smoke sign describes the characteristic angiographic appearance of tiny abnormal intracranial collateral vessel networks in moyamoya disease. Progressive narrowing of the supraclinoid internal carotid arteries and circle of Willis vessels results in extensive small collateral arteria...
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Angiolipoma

Angiolipomas (also sometimes known as haemangiolipomas, vascular lipomas, and fibromyolipomas) are rare soft tissue tumors composed of mature adipocytes and vessels. They can occur essentially anywhere and can be subclassified into infiltrating and non-infiltrating variants 1.  Please refer to ...
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Chordoma

Chordomas are uncommon malignant tumors of the axial skeleton that account for 1% of intracranial tumors and 4% of all primary bone tumors.  They originate from embryonic remnants of the primitive notochord (earliest fetal axial skeleton, extending from the Rathke's pouch to the tip of the cocc...
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Caudal regression syndrome

Caudal regression syndrome represents a spectrum of structural defects of the caudal region. Malformations vary from isolated partial agenesis of the coccyx to lumbosacral agenesis. Epidemiology Caudal regression syndrome is rare, with an estimated incidence of 1:7500-100,000 7,10. The vast m...
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Cauda equina syndrome

Cauda equina syndrome is considered an incomplete cord syndrome, even though it occurs below the conus, and refers to a collection of symptoms and signs that result from severe compression of the descending lumbar and sacral nerve roots. It is most commonly caused by an acutely extruded lumbar d...
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Horizontal gaze palsy with progressive scoliosis

HGPPS is a rare autosomal recessive AR congenital anomaly caused by mutation of ROBO3 gene on chromosome 11. Clinical presentation Abnormal horizontal gaze while normal vertical gaze and kyphoscoliosis. Horizontal gaze requires the action of ipsilateral abducent nerve and contralateral oculomo...
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Arnold's nerve

Arnold's nerve is the auricular branch, also known as the mastoid branch, of the vagus nerve (CN X). Origin and course Arnold's nerve originates from the superior ganglion of the vagus nerve and also has a small contribution from the inferior ganglion of the glossopharyngeal nerve. It ascends ...
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Dorsal thoracic arachnoid web

Dorsal thoracic arachnoid web refers to a thickened band of arachnoid over the dorsal aspect of the cord. It usually causes a focal thoracic cord distortion with consequent neurological dysfunction.  On imaging, it is characterized by a focal dorsal indentation and anterior displacement of the ...
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Lyme disease

Lyme disease, also known as borreliosis, is a condition caused by the bacteria Borrelia burgdorferi, with infection being via the ixodid tick.  Terminology Controversy around Lyme disease centers on chronic infection with some authors doubting its existence 3. There are some terms that help di...
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Rostral sulcus

The rostral sulcus is located medially in the frontal lobe. It is the sulcus which divides the gyrus rectus (or straight gyrus) inferiorly from the inferior portion of the rostral gyrus superiorly1.
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Intracranial pressure

The intracranial pressure (ICP) represents the pressure exerted by the essentially incompressible components (brain tissue and interstitial fluids, blood and CSF) contained within the rigid confines of the skull 1-3. ICP has a normal pulsatile variation derived from the transient changes in blo...
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Transcranial Doppler sonography (ultrasound)

Transcranial​ ​Doppler​ ​(TCD)​, also known as transcranial color-coded duplex sonography (TCCS) is a sonographic study of intracranial structures and blood vessels, used most commonly to identify the hemodynamic state present in the vertebrobasilar circulation and the circle of Willis.  Termin...
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Raised intracranial pressure

Raised intracranial pressure is a pathological increase in the intracranial pressure and is a medical emergency.  Clinical presentation The symptoms and signs of raised intracranial pressure are often non-specific and insidious in onset: headache drowsiness anorexia visual disturbances bl...
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Congenital absence of the internal carotid artery

Congenital absence of the internal carotid artery (ICA) is a rare anomaly that occurs in less than 0.01% of the population. It encompasses agenesis, aplasia, and hypoplasia 1. The most common type of collateral flow is through the circle of Willis, through the anterior communicating artery (ACO...
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Pituitary macroadenoma

Pituitary macroadenomas are the most common suprasellar mass in adults, and responsible for the majority of transsphenoidal hypophysectomies. They are defined as pituitary adenomas greater than 10 mm in size and are approximately twice as common as pituitary microadenomas.  On imaging, they usu...
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Transalar herniation

Transalar (transsphenoidal) herniation describes herniation of brain matter in and around the middle cranial fossa across the greater sphenoid wing and can be ascending or descending. Compression of structures against the sphenoid bone results in symptoms. Pathology Transalar herniation is not...
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CSF rhinorrhea

CSF rhinorrhea refers to a symptom of cerebrospinal fluid (CSF) leakage extracranially into the paranasal sinuses, thence into the nasal cavity, and exiting via the anterior nares. It can occur whenever there is an osseous or dural defect of the skull base (cf. CSF otorrhea). Pathology Etiolog...
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Transsphenoidal basilar skull fracture

Transsphenoidal basilar skull fractures are a particularly serious type of basilar skull fracture usually occurring in the setting of severe traumatic brain injury and with potential for serious complications including damaging the internal carotid arteries and optic nerves as well as high incid...
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Paraganglioma

Paragangliomas, sometimes called glomus tumors, are rare neuroendocrine tumors arising from paraganglia.  Terminology Paraganglia are clusters of neuroendocrine cells dispersed throughout the body and closely related to the autonomic nervous system, with either parasympathetic or sympathetic f...
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Erdheim-Chester disease

Erdheim-Chester disease 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 middle age...
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Tuberculosis (intracranial manifestations)

Tuberculosis of the central nervous system can result from either haematogenous spread from distant systemic infection (e.g. pulmonary tuberculosis) or direct extension from local infection (e.g. tuberculous otomastoiditis). Intracranial manifestations of tuberculosis are protean and can affect...
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Tuberculous pachymeningitis

Tuberculous pachymeningitis is a rare form of CNS tuberculosis characterized by a chronic tuberculous infection leading to a dura mater involvement. Common sites of involvement are cavernous sinuses, floor of middle cranial fossa and tentorium. This condition should not be confused with the com...
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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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Intracranial dermoid cyst

Intracranial dermoid cysts are uncommon lesions with characteristic imaging appearances. They 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 from all...
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Cephalohaematoma

Cephalohaematomas are traumatic subperiosteal hematomas of the skull that are usually caused by birth injury. They are bound between the periosteum and cranium, and therefore cannot cross sutures. Being bound by a suture line distinguishes them from subgaleal hematoma, which can cross sutures. ...
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Intracranial epidural abscess

Intracranial epidural abscess, less commonly called epidural empyema, refers to a pyogenic collection within the epidural space of the head. Spinal epidural abscess is discussed separately. Epidemiology Epidural abscesses are rare overall but together with subdural empyema account for around 2...
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Retinal detachment

Retinal detachment is a detachment of the neurosensory retina from the underlying pigmented choroid. Apposition of the retinal pigmented epithelium to the overlying retina is essential for normal retinal function. Terminology Rhegmatogenous retinal detachment: there is fluid ingression from th...
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Lipoma

Lipomas are benign tumors composed of mature adipocytes. They are the most common soft tissue tumor, seen in ~2% of the population.  Epidemiology Patients typically present in adulthood (5th-7th decades). Clinical presentation Typically lipomas are subcutaneous in location and present in adu...
Article

Caroticocavernous fistula

Caroticocavernous fistulas (CCF) represent abnormal communication between the carotid circulation and the cavernous sinus. They can be classified as direct or indirect which are separate conditions with different etiologies.   Epidemiology Direct CCFs are often secondary to trauma, and as such...
Article

Hyperosmolar hyperglycemic state

Hyperosmolar hyperglycemic state (HHS) (previously known as hyperosmolar non-ketotic coma (HONK)) is a serious metabolic derangement that can occur in patients with diabetes mellitus, predominantly those with type 2. While there are no distinct imaging features, it is useful for a radiologist to...
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Central nervous system embryology

Central nervous system (CNS) embryology is complex, and below is a brief summary of its development.  The early CNS begins as a simple neural plate that folds to form a groove then tube, open initially at each end. Within the neural tube stem cells generate the two major classes of cells that m...
Article

Gudden's commissure

Gudden’s commissure, also called the ventral supraoptic decussation, is one of three tracts that comprise the supraoptic commissure 1,2.  The remaining two tracts that comprise the supraoptic commissure are Meynert's commissure (dorsal supraoptic commissure) and the anterior hypothalamic commiss...
Article

Preoccipital notch

The preoccipital notch is an indentation approximately 5 cm in front of the occipital pole on the inferolateral border of the temporal lobe. It is a significant landmark as the occipital lobe lies behind the lateral parietotemporal line, joining the preoccipital notch and the parieto-occipital s...
Article

Leukemia (CNS manifestations)

Leukemia CNS manifestations can be divided into those related to the disease itself and those associated with its treatment. Leukaemias are hematologic malignancies in which occur a proliferation of hematopoietic cells at an undifferentiated or partially differentiated stage of maturation. CNS ...
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Perimesencephalic subarachnoid hemorrhage

Perimesencephalic subarachnoid hemorrhage (PMSAH) is a distinct pattern of subarachnoid hemorrhage (SAH), which is centered on the basal cisterns around the midbrain. Epidemiology Perimesencephalic subarachnoid hemorrhage is rare with an incidence of 0.5 in 100 000 in adults 4. PMSAH represent...
Article

IgG4-related disease

IgG4-related disease (IgG4-RD) is a systemic disease that is characterized 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

Parkinson disease

Parkinson disease (PD), also known as idiopathic parkinsonism, is a neurodegenerative disease and movement disorder characterized by resting tremor, rigidity and hypokinesia due to progressive degeneration of dopaminergic neurons in the substantia nigra.  Epidemiology Parkinson disease is by f...
Article

Central neurocytoma

Central neurocytomas are WHO grade II neuroepithelial intraventricular tumors with fairly characteristic imaging features, appearing as heterogeneous masses of variable size and enhancement within the lateral ventricle, typically attached to the septum pellucidum. They are typically seen in youn...
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Embryonal tumors with multilayered rosettes (ETMR)

Embryonal tumors with multilayered rosettes (ETMR) are rare small round blue cell tumor of the central nervous system and are one of the most aggressive brain tumors usually encountered in children.  Terminology Previously embryonal tumors with multilayered rosettes (ETMR) were known as embryo...
Article

Anterior choroidal artery

The anterior choroidal artery (AChA) supplies several crucial anatomical structures of the brain important for vision and motor control. Identification of AChA is important because of its strategic and extensive area of supply as well as large variations in the territorial distribution. Gross a...
Article

Progressive postnatal pansynostosis

Progressive postnatal pansynostosis (PPP) is a rare form of craniosynostosis characterized by the late fusion of all cranial sutures. Epidemiology This type of craniosynostosis occurs insidiously after birth and presents later in life unlike other types of craniosynostosis which occur during t...
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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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