Optical coherence tomography manifestations of primary vitreoretinal lymphoma.

BACKGROUND: Primary vitreoretinal lymphoma (PVRL), a subset of primary central nervous system lymphoma (PCNSL), is a high-grade malignant tumor that shows various chorioretinal findings. Optical coherence tomography (OCT) is useful for detecting these lesions, and various abnormalities on OCT images have been reported. The purpose of this report was to investigate retrospectively the OCT manifestations of various disease stages and compare the manifestations of pretreatment, recurrent, and chronic cases. METHODS: We reviewed the medical charts and OCT images of 38 consecutive cases with PVRL. When abnormalities were detected on OCT images, the patients were classified based on the treatment of the primary disease: pretreatment if not treated, recurrent if treated previously, and chronic when chronic changes. RESULTS: Twenty-six eyes (20 cases) had abnormalities in the post-pole OCT images, i.e., 16 eyes (12 cases) were in the pretreatment group, seven eyes (five cases) were in the recurrent group, and five eyes (five cases) were in the chronic group. Two eyes (two cases) had abnormalities on OCT in the pretreatment and recurrent or chronic stages. The pretreatment and recurrent groups had subretinal or retinal pigment epithelium (RPE) level abnormalities more often than intraretinal changes. Twelve of 16 pretreated eyes and all seven eyes with recurrent disease had subretinal or RPE level abnormalities. One pretreatment case and three recurrent cases had atypical OCT manifestations of intraretinal (round lesions) or epiretinal changes (villous-shaped lesions). CONCLUSIONS: Although pretreatment cases and recurrent cases showed similar OCT abnormalities and the specific changes in the various disease stages were unclarified, collecting OCT data from various disease stages will facilitate detection of typical OCT changes of PVRL and lead to early diagnosis and treatment.

Enrichment of corneal epithelial stem/progenitor cells using cell surface markers, integrin alpha6 and CD71.

Corneal epithelial stem cells are believed to reside in the basal layer of the limbal epithelium, but no definitive cell surface markers have been identified. For keratinocytes, stem/progenitor cells are known to be enriched by cell surface markers, integrin alpha(6) and CD71, as a minor subpopulation which shows high integrin alpha(6) and low CD71 expressions (alpha(6)(bri)/CD71(dim)). In the present study, we investigated the possibility that corneal epithelial stem cells can be enriched by integrin alpha(6) and CD71. The alpha(6)(bri)/CD71(dim) cells were separated by fluorescence-activated cell sorting, as a minor subpopulation of the limbal epithelial cells. They were enriched for relatively small cells, showing a higher clonogenic capacity and expression of stem cell markers, but a lower expression of differentiation markers, compared to other cell populations. The cells were localized immunohistochemically in the basal region of the limbal epithelium. These results indicate that the alpha(6)(bri)/CD71(dim) subpopulation enriched corneal epithelial stem cells.