Brain Imaging Case Review Series - Vocabulary Flashcards

This set of vocabulary flashcards provides definitions for key radiographic signs, anatomical structures, and syndromes highlighted in the Brain Imaging Case Review Series, covering vascular, neoplastic, and developmental pathologies.

Recurrent artery of Heubner

Also known as the medial striate artery, it typically arises from the A2 segment of the ACA and supplies the head of the caudate nucleus, the anterior portion of the lentiform nucleus, and the anterior limb of the internal capsule.

CT swirl sign

A radiographic appearance on noncontrast CT characterized by an area of lower attenuation within a high-density extra-axial hematoma, representing unclotted fresh blood or acute active bleeding.

Transependymal edema

A form of interstitial edema seen in acute obstructive hydrocephalus, manifested as hypodensity around the ventricles on CT or hyperintensity on T2W MRI due to the seepage of cerebrospinal uid.

Parinaud syndrome

A clinical triad consisting of upward gaze palsy, pupillary light-near dissociation, and convergence-retraction nystagmus resulting from compression of the superior tectal plate.

ADC pseudonormalization

An imaging phenomenon where Apparent Diffusion Coefcient values appear to return to normal approximately 1 week after an ischemic infarct, masks the cytotoxic edema stage.

Duret hemorrhages

Small hemorrhages typically located in the midline of the pons or medulla that occur due to rapidly developing brain herniation.

Persistent trigeminal artery (PTA)

The most common embryonic carotid–vertebrobasilar anastomosis to persist into adulthood, usually arising from the precavernous internal carotid artery.

Dual-rim sign

An MRI feature seen on susceptibility-weighted imaging in brain abscesses, consisting of a hypointense outer rim and a relatively hyperintense inner rim surrounding the abscess cavity.

McDonald criteria (2017)

Revised diagnostic criteria for multiple sclerosis that assess dissemination in space across four regions: periventricular, cortical and/or juxtacortical, infratentorial, and spinal cord.

Alanine peak

An MR spectroscopy resonance found at $1.48\,ppm$ that serves as a useful feature for distinguishing meningiomas from other dural-based mass lesions.

T2-FLAIR mismatch sign

An imaging biomarker predictive of the IDH-mutant, 1p/19q non-codeleted molecular subtype in lower-grade infiltrating gliomas.

2-hydroxyglutarate

A metabolite detected at $2.25\,ppm$ on MR spectroscopy that serves as a highly specic imaging biomarker for isocitrate dehydrogenase (IDH) mutant gliomas.

McCune\u2013Albright syndrome (MAS)

A genetic disorder characterized by the clinical triad of polyostotic brous dysplasia, precocious puberty, and "coast of Maine" café au lait spots.

Trilateral retinoblastoma

A condition involving bilateral retinoblastomas associated with an intracranial neuroblastic tumor, most commonly a pineoblastoma (the "third eye").

Colpocephaly

The disproportionate enlargement of the occipital horns of the lateral ventricles, often producing a "racing car" or "Texas longhorn" appearance on imaging.

Scaphocephaly

Also known as dolichocephaly, this is the most common form of craniosynostosis resulting from premature closure of the sagittal suture.

Molar tooth sign

A midbrain morphology involving elongated, thickened superior cerebellar peduncles and a deep interpeduncular cistern, characteristic of Joubert\u2019s syndrome.

Coca-Cola bottle sign

A radiographic sign in thyroid-associated orbitopathy where there is enlargement of the extraocular muscle bellies with characteristic sparing of the tendinous insertions.

Bruns syndrome

A clinical presentation of sudden headache, vertigo, and vomiting triggered by head movement, typically caused by a mobile intraventricular lesion like neurocysticercosis.

Osteoporosis circumscripta

The characteristic radiographic appearance of well-dened osteolytic regions, most common in the frontal or occipital bones, during the early active phase of Paget\u2019s disease.

Trident sign

A T2-weighted MRI appearance in osmotic demyelination syndrome where the central pons is hyperintense while the peripheral pons and corticospinal tracts are spared.

Mount Fuji sign

A sign of tension pneumocephalus on CT where subdural air separates and compresses the frontal lobes, resembling the silhouette of a mountain.

Probst bundles

Longitudinal white matter tracts that run parallel to the interhemispheric ssure instead of crossing the midline in patients with agenesis of the corpus callosum.

Vein of Markowski

The median prosencephalic vein, a precursor to the vein of Galen, which remains persistent in children with vein of Galen malformations.

Tram-track sign

A pattern of enhancement or calcication along the optic nerve sheath, surrounding the nonenhancing optic nerve, typically seen in optic nerve meningiomas.

Vein of Labbé

Also known as the inferior anastomotic vein, it connects the supercial middle cerebral vein to the transverse sinus.

Ivy sign

Sulcal FLAIR hyperintensity reecting slow-owing pial collateral circulation in patients with moyamoya disease.

Modified Boston Criteria

A set of clinical and radiographic standards used to diagnose cerebral amyloid angiopathy (CAA) without a biopsy based on patterns of lobar hemorrhage.

Marcus Gunn pupil

An abnormal pupillary finding indicating a relative afferent pupillary defect (RAPD), commonly tested with the swinging light test in optic neuritis cases.

Mineralizing microangiopathy

A histopathologic process involving the microvasculature of the CNS after combined radiation and chemotherapy, leading to basal ganglia calcication and T1 hyperintensity.

MISME

An acronym representing Multiple Inherited Schwannomas, Meningiomas, and Ependymomas, the hallmark tumors of Neurobromatosis Type 2.

Posterior pituitary bright spot

A normal focal T1 hyperintense signal located at the posterior aspect of the sella turcica, believed to result from the storage of vasopressin.

Gelastic seizures

A unique seizure type presenting as involuntary laughter, characteristically associated with tuber cinereum hamartomas.

Hot-cross bun sign

A cruciform T2 hyperintensity in the pons seen in multiple system atrophy cerebellar type (MSA-C), caused by degeneration of pontine neurons.

Textiloma

Also known as a gossypiboma, this is a foreign body reaction or granuloma resulting from a surgical sponge or hemostatic material left in the surgical bed.

CLOCC

An acronym for Cytotoxic Lesion of the Corpus Callosum, which presents as restricted diffusion (typically in the splenium) due to cytokine-induced or excitotoxic injury.

Betz cells

Giant pyramidal motor neurons located in the precentral gyrus (motor strip) that are lost in amyotrophic lateral sclerosis (ALS).

SMARCB1

The hallmark genetic mutation, also known as INI1, whose loss of expression denes the diagnosis of atypical teratoid/rhabdoid tumors (AT/RT).

Artery of Davidoff and Schechter

A meningeal branch of the P1 segment of the posterior cerebral artery that typically becomes prominent in tentorial dural arteriovenous stulas.

Saltzman type I

A classication of persistent trigeminal artery where the artery supplies the distal vertebrobasilar circulation and the posterior communicating artery is absent.

Bill\u2019s bar

A vertical ridge of bone that separates the facial nerve from the superior vestibular nerve in the lateral aspect of the internal auditory canal.

Terson syndrome

The clinical occurrence of vitreous or retinal hemorrhage in the setting of intracranial subarachnoid hemorrhage.

Motor oil cysts

A descriptor for the waxy, proteinaceous, and often T1-hyperintense contents of adamantinomatous craniopharyngiomas.

Ballooning sign

The "box-like" conguration of the frontal horns of the lateral ventricles resulting from atrophy of the caudate nuclei in Huntington\u2019s disease.

Rhombencephalosynapsis

A rare cerebellar malformation involving agenesis of the vermis and midline fusion of the cerebellar hemispheres, peduncles, and dentate nuclei.