No abstract

1 Neumann MA, Cohn R. Progressive subcortical gliosis, a rare form of presenile dementia. After five days on a standard low monoamine diet and after eight hours of bed rest, a lumbar puncture was performed with the patient in the lateral decubitus position. Routine CSF studies were carried out on the initial 4 ml of CSF; for assay of HVA and 5-HIAA an additional 10 ml was collected in four 2-5 ml aliquots. All aliquots of CSF were frozen immediately on dry ice and stored at -70°C. To minimise the effects of CSF monoamine concentration gradients, the tube containing the fourth aliquot of CSF was used for analysis. Extraction, derivatisation, and measurement of HVA and 5-HIAA were performed as previously described2 on a Hewlett Packard MSD 5970 mass spectrometer-gas chromatograph 5890 with preserved acid extracts of CSF supematant. For genetic characterisation, the polymerase chain reaction was performed with oligonucleotides flanking the CAG triplet repeat region on chromosome 6p and chromosome 14q as previously described.34 Magnetic resonance imaging was performed on a 0 5 Tesla unit scanner (Picker International Inc, model HPQ). Three 5-0 mm mediosagittal images were obtained parallel to the longitudinal fissure. The pontine (an elliptical pontine area bounded by the anterior surface of the pons, the interpeduncular fossa, and the putative medial lemniscus) and the cerebellar areas in the mediosagittal plane were quantified with ANALYZE version 6-2 software (Biomedical Imaging Resources, Mayo Foundation) on a DIGITAL DEC station 5000/125. Triplicate samples were measured to compute the mean area in mm2 and the SD. Identical areas from 10 normal volunteers were used for comparisons.Mean concentrations of HVA and 5-HIAA in CSF were calculated and statistical differences were determined by paired two tailed t test. The relation between the monoamine metabolites and cerebellar and pontine areas was examined by linear regression.All 20 patients (12 male, eight female) had variable degrees of cerebellar ataxia without parkinsonian signs. Five study participants from two families showed a repeat expansion on chromosome 6p (spinocerebellar atrophy type 1; SCAl), nine patients from three families showed a repeat expansion on chromosome 14q (SCA3) and six patients from three families had neither genotype. In the entire group of patients with ADA, the mean (SD) pontine (315-9 (82-1)) and cerebellar (731-3 (178-6)) areas were significantly (P < 0-01) smaller than normal (pons 393.5 (44-7); cerebellum 1120-0 (133-4)). The pontine area was linearly related to the decreasing concentrations of HVA in CSF (P = 0 05, r = 0 50, y = -2-3 + 0 09) but the cerebellar area was not related to the concentrations of HVA or 5-HIAA in CSF. The HVA concentrations in CSF and the ratio of CSF HVA/5-HIAA were significantly lower in the entire group of patients with ADA than in normal controls (table). Although the cerebellar size was smaller (P = 0-01) in patients with ) than in patients with ), no differences in the concentrations of monoamin...