Radiology Key

Congenital Malformations MYELOMENINGOCELE AND MYELOCELE KEY FACTS Myelomeningocele and myelocele are both midline bone defects through which meninges and/or neural placode (unfolded spinal cord) are visible; most discovered by in…

Neurocutaneous Syndromes NEUROFIBROMATOSIS TYPE 1, ASTROCYTOMAS AND NEUROFIBROMAS KEY FACTS Autosomal dominant (chromosome 17) or sporadic (50%) disorder, ten times more common than NF-2; prominent cutaneous lesions, plexiform neurofibromas, and…

Degenerative and Latrogenic Disorders PANTOTHENATE KINASE DEFICIENCY (HALLERVORDEN-SPATZ SYNDROME) KEY FACTS Rare autosomal recessive disorder (abnormal gene: 20p13); deficiency of pantothenate kinase leading to accumulation of cysteine, free radicals, and…

Intra-Axial Tumors Supratentorial Tumors ASTROCYTOMA, LOW GRADE KEY FACTS Account for 10% to 30% of cerebral gliomas in adults. Histologically, low-grade astrocytomas are fibrillary (diffuse), and over 80% eventually degenerate…

Vascular Disorders ▪ SPINAL CORD CAVERNOUS MALFORMATION KEY FACTS Histologically, cavernous malformations are composed of dilated vascular sinusoids devoid of smooth muscle and elastic fibers; there are no normal intervening…

Metabolic Disorders AMINO ACID DISORDERS KEY FACTS In this rare group of disorders, amino acid pathways are deficient, and proteolipids, which are essential for formation of myelin, are abnormal. Phenylketonuria…

Extra-Axial Masses MENINGIOMA KEY FACTS Most common extra-axial adult tumor; most common intracranial tumors (15% to 20%) in adults. Occurs mainly in middle-aged women (possibly because of increased sensitivity of…

Stroke ACUTE (<24 HOURS) MIDDLE CEREBRAL ARTERY INFARCT, COMPUTED TOMOGRAPHY KEY FACTS Cerebral strokes are third most common cause of death in the United States; mortality with each episode varies…

Leukodystrophies ADRENOLEUKODYSTROPHY KEY FACTS Most important peroxisomal disorder which is characterized by very long-chain fatty acids that are not metabolized and are elevated in serum and other body fluids. The…

Vascular Malformations ARTERIOVENOUS MALFORMATIONS KEY FACTS Congenital in nature, generally present in middle age (65% in patients >40 years of age). Very rare, incidence of 1:100,000 individuals. Arteriovenous malformations (AVMs)…