Chromosomal Diseases Abnormal total number of chromosomes (aneuploidy) or structural rearrangement (deletion, translocation, duplication). Clinical manifestations: mental retardation (most common), variable congenital malformations. Trisomy 21 (Down Syndrome) Extra copy of…
Marcus Gunn and Möbius Syndromes Marcus Gunn Syndrome Eyelid rises when mouth opens (jaw drops); lid comes down when mouth closes (jaw rises). “Jaw-winking.” Usually accompanied by congenital unilateral ptosis….
Structural Malformations Malformations of Cerebral Hemispheres and Agenesis of Corpus Callosum Holoprosencephaly: single-lobed brain, one undivided ventricle. Failure of cleavage of telencephalon and diencephalon. Incomplete variants: semilobar, lobar holoprosencephaly. Associated…
Laurence-Moon-Biedl Syndrome Clinical Features Variable manifestations, primarily combination of obesity and hypogonadism in childhood or adolescence. Obesity (85% to 95%); mental retardation (70% to 85%); retinitis pigmentosa (92% to 95%);…
Static Disorders of Brain Development Developmental Disorders of Motor Function Minor Motor Disability Minor impairments of motor coordination; clumsiness. Neurologic basis rarely known. Often occur in children with other specific…
Floppy Infant Syndrome Decreased muscle tone throughout body. Limply hanging limbs when infant held suspended in prone position. Most common causes (75% of cases): perinatal insult to brain or spinal…
Neonatal Neurology Intracranial Hemorrhage Full term: (a) supratentorial subdural (rare; difficult deliveries); (b) primary subarachnoid of venous origin (focal seizures, benign course). Premature (≤32 weeks of gestation): parenchymal, periventricular origin….
Decompression Sickness Incidence of decompression sickness in divers: 1% to 30%. Spinal cord most common site of neurologic lesions. Lesions result from bubbles of normally dissolved gases occluding vessels or…
Electrical and Lightning Injury High-voltage electric shock or lightning stroke damages CNS, motor neurons, peripheral nerves. Pathology: lesions in brain or spinal cord. Myelomalacia and other nonspecific lesions seen without…
Radiation Injury Early (Acute) Effects (1 to 6 Weeks) Edema, headache, nausea, vomiting, alopecia; hyperpigmentation, desquamation of skin. Complications in 50% for daily dose fractions of 750 cGy; <200 cGy…
