Abstract
Abstract: :
Purpose: To study and compare the role of liquid–based cytology, cytospin, cell block, immunohistochemistry, flow cytometry and gene rearrangement by PCR in the diagnosis of lymphomas, non–granulomatous and granulomatous chronic vitritis, endophthalmitis, and other entities in vitreous specimens. Methods: We reviewed 150 consecutive vitrectomy specimens including vitrectomy taps and washings retrospectively from 1998 to 2003 from the Ophthalmic Pathology Laboratory, Baylor College of Medicine. We analyzed and compared the yield of the different techniques used to confirm a diagnosis of lymphomas, non–granulomatous and granulomatous chronic vitritis, endophthalmitis, and other entities. Results: 15 cases (10%) were reported as lymphomas (13 cases of B–cell type and 2 cases of T–cell type). Of the remaining vitrectomy specimens, 37 (24%) were non–granulomatous chronic vitritis, 51(34%) were granulomatous vitritis, 10 (7%) were endophthalmitis, and 33 (21%) were other entities including hemorrhage, asteroid hyalosis, malignant melanoma, etc. There was an adequate sample for diagnosis in 97% of the vitrectomy specimens. Lymphomas were diagnosed using a combination of liquid–based cytology and flow cytometry in 12 cases, liquid–based cytology and gene rearrangement by PCR in 1 case, and cell block and immunohistochemistry in 2 cases. Liquid–based cytology was sufficient for triaging and diagnosing in 79% of the remaining non–lymphoma vitrectomy specimens. Conclusions: : This study demonstrates the high diagnostic yield of liquid–based cytology using 1 ml or less of undiluted vitreous. It also allows for adequate triaging of the specimen when ancillary studies are required, especially when minimal amount of specimen is available. Flow cytometry proved to be a valuable adjunct in diagnosing the cases of intraocular lymphomas.
Keywords: vitreous • cytology • flow cytometry