We assessed the morphology and numbers of cells in 50 CSF samples obtained from 50 consecutive lumbar punctures. After centrifugation of the aliquots, 400 microL was used for cytocentrifugation on PLC and plain glass slides. After Giemsa staining, random area cell counts were made for a total of 100 microscopic fields (using a 40 x objective), and cytomorphology was assessed.