B-cell lymphoma line (Raji) viability and surface marker expression minimally affected by 20- and 25-gauge vitrectomy systems analyzed by flow cytometry

25-gauge transconjunctival diagnostic vitrectomy in suspected cases of intraocular lymphoma: a case series and review of the literature

AIM

To report the cytology results of 25-gauge transconjunctival (25G-TSV) diagnostic vitrectomy in cases suspicious for intraocular lymphoma (IOL), and compare the results to those reported in the literature.

METHODS

Clinical and cytopathological records of 18 vitreous biopsy specimens obtained via 25G-TSV diagnostic vitrectomy in 12 patients suspicious for IOL were reviewed retrospectively. A review of the literature in regards to the diagnostic yields of vitreous specimens obtained via 25-gauge and 20-gauge diagnostic vitrectomy in suspected cases of IOL was performed.

RESULTS

Eighteen eyes from 12 patients with clinical suspicion of IOL underwent diagnostic 25G-TSV. The cytopathological investigations demonstrated IOL in 15 eyes (83.3%). Vitreous analysis was non-diagnostic in 3 eyes (16.7%).

CONCLUSION

Twenty-five-gauge diagnostic vitrectomy yields adequate sample for cytological evaluation of the vitreous in cases suspicious for IOL. The diagnostic results of the 25G-TSV in the current study are superior to those reported for 20-gauge vitrectomy but equivalent to those reported for 25G-TSV in the published literature.

Evaluation of Cytologic Specimens Obtained during Experimental Vitreous Biopsy Using B-Cell Lymphoma Line

Purpose

To investigate the role of vitrectomy in the diagnosis of intraocular lymphoma by evaluating the effects of aspiration pressure and cut rate on cell viability and diagnostic yield.

Methods

Cells of the human Burkitt lymphoma cell line Namalwa were processed by 20-G vitrectomy under 2 different aspiration pressures and at different cut rates. Some samples were divided into high and low aspiration pressure groups and were then divided into 6 subtypes according to the different cut rates (0, 300, 600, 800, 1500, or 2500 cuts per minute [cpm]). Other samples were treated with dexamethasone sodium phosphate for 48 hours with or without further culturing in cell culture media afterward. The cell viability in each subtype group was determined using trypan blue staining and the Cell Counting Kit–8.

Results

The number of viable cells was reduced with increasing cut speed under high aspiration pressure. Cell viability began to decrease at 600 cpm and was lowest at 2500 cpm. Exposure to dexamethasone sodium phosphate induced destruction of cellular structure and a significant reduction in cell viability. However, cell viability could be recovered with further culture in cell culture media for 1 week.

Conclusions

A cut rate of 600 cpm or less is recommended during diagnostic vitrectomy to confirm a clinical suspicion of primary intraocular lymphoma. Corticosteroid treatment can lower the diagnostic yield due to reduced cell viability and damaged cellular structure.