Articles
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More than 200 results
Article
Pineocytoma
Pineocytomas are relatively benign (WHO grade 1) pineal parenchymal tumors that have a relatively good prognosis.
On imaging, they generally appear as a well-demarcated tumor less than 3 cm in its greatest dimension, iso- to hyperattenuating on CT, hypo- to isointense on T1, and hyperintense on...
Article
Lemierre syndrome
Lemierre syndrome, also known as postanginal septicemia, refers to thrombophlebitis of the internal jugular vein(s) with distant metastatic anaerobic septicemia in the setting of initial bacterial oropharyngeal infection such as pharyngitis/tonsillitis into lateral pharyngeal spaces of the neck ...
Article
Flame sign (carotid)
The flame sign refers to a gradual tapering of contrast opacification in the mid-cervical internal carotid artery, sparing the carotid bulb. The sign can be observed on angiography (digital subtraction angiography 1, CT angiography 1, or contrast-enhanced MR angiography 2) in either of two scena...
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Perivascular spaces
Perivascular spaces, also known as Virchow-Robin spaces, are fluid-filled spaces that surround small arterioles, capillaries and venules in the brain. Those that surround perforating vessels are frequently seen on routine MRI imaging.
Despite having been described well over a century ago and se...
Article
Spinal meningioma
Meningiomas arising from the coverings of the spinal cord are one of the two most common intradural extramedullary spinal tumors, representing 25-30% of all such tumors 2.
This article specifically relates to spinal meningiomas. For a discussion on intracranial meningiomas and a general discus...
Article
Combined cerebral edema
Combined cerebral edema is a type of cerebral edema in which there is a mixed pattern of different types of cerebral edema (cytotoxic, vasogenic or osmotic).
It is usually associated with severe systemic damage, such as:
hypertensive crises
severe sepsis / severe inflammatory condition
hypox...
Article
Neurodegeneration with brain iron accumulation
Neurodegeneration with brain iron accumulation (NBIA), is a heterogeneous group of rare genetic disorders characterized by accumulation of iron in the basal ganglia, which results in variable neurological disorders including extrapyramidal symptoms, neuropsychiatric and visual symptoms.
Numerou...
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Charcot-Marie-Tooth disease
Charcot-Marie-Tooth (CMT) disease, also known as hereditary motor and sensory neuropathy (HMSN), refers to a heterogeneous group of inherited peripheral neuropathies rather than a single clinical entity 9.
Epidemiology
The prevalence of CMT has been reported at ~45 cases (range 10-82) per 100,...
Article
Brainstem glioma
Brainstem gliomas are primary tumors most frequently involving the pons and are typically diagnosed in children.
Terminology
Brainstem glioma is not a formal diagnosis but rather a catch-all term encompassing a heterogeneous group that varies greatly in histology and prognosis. It was useful, ...
Article
Neuroblastoma
Neuroblastomas are tumors of neuroblastic origin. Although they may occur anywhere along the sympathetic chain, the vast majority arise from the adrenal gland.
They represent the most common extracranial solid childhood malignancy and are the third most common childhood tumor after leukemia and...
Article
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...
Article
Diffuse pediatric-type high-grade gliomas, H3-wildtype and IDH-wildtype
Diffuse pediatric-type high-grade gliomas, H3-wildtype and IDH-wildtype are high-grade pediatric tumors included in the 5th Edition (2021) of the WHO brain tumor classification.
Terminology
Diffuse pediatric-type high-grade gliomas H3-wildtype and IDH-wildtype are classified among the "pediatr...
Article
External auditory canal atresia
External auditory canal atresia, also known as congenital aural atresia, is characterized by complete or incomplete bony atresia of the external auditory canal (EAC), often in association with a dysplastic auricle and an abnormal middle ear cavity or ossicles.
Epidemiology
The incidence is 1 i...
Article
Hemimegalencephaly
Hemimegalencephaly is a rare congenital disorder of cortical formation characterized by hamartomatous overgrowth of all or part of a cerebral hemisphere. This overgrowth results from either increased proliferation or decreased apoptosis (or both) of developing neurons 2.
Epidemiology
Hemimegal...
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Superior vermian vein
The superior vermian vein is formed in the midline over the superior aspect of the cerebellar vermis (over the anterior lobe) by multiple tributaries draining not just the subjacent vermis but also the adjacent cerebellar hemispheres. These tributaries most often coalesce into a single trunk ove...
Article
Loss of the insular ribbon sign
The loss of the insular ribbon sign refers to a loss of definition of the gray-white interface in the lateral margin of the insular cortex ("insular ribbon") and is considered an early (hyperacute to acute) CT sign of MCA territory infarction.
The insular cortex is more susceptible to ischemia ...
Article
Subdural hygroma
Subdural hygromas (alternative plural: hygromata 9), or subdural effusions, refer to the accumulation of fluid in the subdural space. Where it is associated with head injury it can also be termed a traumatic subdural hygroma.
Epidemiology
Subdural hygromas are encountered in all age-groups bu...
Article
Facial nerve
The facial nerve is the seventh (CN VII) cranial nerve and comprises two roots, a motor root and a smaller mixed sensory, taste and parasympathetic root, known as nervus intermedius, which join together within the temporal bone (TA: nervus facialis or nervus cranialis VII).
The facial nerve has...
Article
Meningocele
Meningoceles (also spelled meningocoele) are protrusions of the meninges through a defect or weak point in the skull or spine, usually involving the soft tissues beneath the surface of the skin. They are typically categorized into congenital, iatrogenic (e.g. following a craniotomy, sinus surger...
Article
Meningeal hemangiopericytoma (historical)
Hemangiopericytomas of the meninges are rare tumors of the meninges, now considered to be an aggressive form of solitary fibrous tumors of the dura. They often present as large and locally aggressive dural masses, frequently extending through the skull vault. They are difficult to distinguish on...