Diagnostic cytology of cerebrospinal fluid by the cytocentrifuge method

Seven hundred seventy-five cerebrospinal fluid samples from 748 patients with neurologic and non-neurologic disorders were studied by a modified cytocentrifuge technic for diagnostic evaluation. The technic proved to be simple, rapid, and inexpensive, and provided consistently good artifact-free morphologic detail suitable for differential and cytochemical analysis. Specimens from 525 patients (70%) had normal cytologic characteristics regardless of underlying condition. Examination of the cerebrospinal fluids of 40 patients (5%) revealed hemorrhage, confirming the presence of intracranial hemorrhage. Inflammatory reactions of various types (acute, chronic, and mixed) were encountered in 120 patients (16%). The appearance of neoplastic cells in cerebrospinal fluid was sometimes the first indication of malignancy. Twenty-six patients (4%) had tumor cells of various types in their cerebrospinal fluids on initial examination. Twenty patients (3%) had abnormal cells initially classified as suspect for malignancy; tumor cells subsequently were found in the spinal fluids of 11 of these, while five were proven to have neoplasms at autopsy without having had tumor cells found in their cerebrospinal fluids. There was no false-positive result. Samples of cerebrospinal fluid from 17 patients (2%) were classified as non-diagnostic, usually because of autolysis.