Differential Diagnosis of Nervous System Disorders
Cerebral Atrophy
= irreversible loss of brain substance + subsequent enlargement of intra- and extracerebral CSF-containing spaces (hydrocephalus ex vacuo = ventriculomegaly)
- DIFFUSE BRAIN ATROPHY
Cause:- Trauma, radiation therapy
- Drugs: dilantin, steroids, methotrexate, marijuana, hard drugs, chemotherapy, alcohol, hypoxia
- Demyelinating disease: multiple sclerosis, encephalitis
- Degenerative disease: eg, Alzheimer disease, Pick disease, Jakob-Creutzfeldt disease
- Cerebrovascular disease + multiple infarcts
- Advancing age, anorexia, renal failure
- enlarged ventricles + sulci
- FOCAL BRAIN ATROPHY
Cause: vascular / chemical / metabolic / traumatic / idiopathic (Dyke-Davidoff-Mason syndrome) - REVERSIBLE PROCESS SIMULATING ATROPHY
(in younger people)
Cause: anorexia nervosa, alcoholism, catabolic steroid treatment, pediatric malignancy
- prominent sulci
- ipsilateral dilatation of basal cisterns + ventricles
- ex vacuo dilatation of ventricles
- thinning of gyri
- focal areas of periventricular high signal intensity
- increased iron deposition in putamen approaching the concentration in globus pallidus
- dilatation of Virchow-Robin perivascular space
Cerebellar Atrophy
- WITH CEREBRAL ATROPHY
= generalized senile brain atrophy - WITHOUT CEREBRAL ATROPHY
- Olivopontocerebellar degeneration / Marie ataxia / Friedreich ataxia
- onset of ataxia in young adulthood
- Ataxia-telangiectasia
- Ethanol toxicity: predominantly affecting midline (vermis)
- Phenytoin toxicity: predominantly affecting cerebellar hemispheres
- Idiopathic degeneration 2° to carcinoma (= paraneoplastic), usually oat cell carcinoma of lung
- Radiotherapy
- Focal cerebellar atrophy:
- infarction
- traumatic injury
Hippocampal Atrophy
- Alzheimer Disease
- Mesial temporal sclerosis
- Normal in octogenarians
Outline