Quantitative cytocentrifugation in the evaluation of cerebrospinal fluid

Five hundred sixteen samples of cerebrospinal fluid (CSF) were subjected to cytocentrifugation to determine whether this technique is reliable in quantifying the cells present while simultaneously allowing precise cytologic identification of the types of malignant and atypical cells present. Cell counts obtained by the cytocentrifuge method were comparable to those obtained by the standard hemocytometer method. Because of the larger volume of fluid used in cytocentrifugation, cells (0.2/cu mm) were found in 264 specimens that would have been considered devoid of cells by hemocytometry. Six of these samples contained malignant cells. The Wright's-stained cytocentrifuged specimens also allowed precise identification of hematopoietic cell types. CSF cytocentrifugation offers the advantages of (1) a simple and rapid method of quantifying the number of cells present, (2) use of larger volumes than the hemocytometer method, thereby minimizing the possibility that the specimen will be classified as acellular, and (3) improved morphology of hematopoietic cell types by use of the Wright's stain. We conclude that the cytocentrifugation method is useful in the routine quantification and diagnosis of CSF specimens.