Objective To observe the effect of blue light on apoptosis of cultured human retinal pigment epithelial (RPE) cells in vitro. Methods Human RPE cells were exposed to blue light, and the cells were divided into 3 groups: group A, with various intensity of illumination; group B: with same intensity but different time of illumination; group C: with same intensity and time of illumination but different finish time of the culture. The apoptosis of RPE cells was observed by TdT-dUTP terminal nick-end labeling (TUNEL) and annexin V-fluoresein isothiocyanate (FITC)/propidium iodide (PI) flow cytometry, and transmission electron microscopy. Results The positive cells stained by TUNEL shrinked and turned round, whose nuclei concentrated and congregated like the crescent or hat. Cracked nuclei and membrane bleb were found. Swollen mitochondrial, disappeared inner limiting membrane of mitochondria, and dilation of the rough endoplasmic reticulum with metabolite were observed by transmission electronmicroscopy. In group A, mild damage of RPE cells was found when the threshold value of the intensity of illumination was less than（500±100）lx, and the apoptosis and necrosis of RPE cells aggravated as the intensity of illumination increased; in group B, as the time of illumination extended, the number of apoptotic RPE cells didn′t increase while the necrosis increased; in group C, 6 and 12 hours after illumination, apoptosis of cells was the main injury, while apoptosis with necrosis was found and necrotic cells increased as the time of illumination was prolonged. Conclusions Illumination with blue light may cause damages of human RPE cells in vitro, with the modalities of apoptosis, apoptotic necrosis and necrosis. The extent of injury is dependent on intensity and duration of the illumination. (Chin J Ocul Fundus Dis, 2005, 21: 384-387)
Objective To investigate the clinical features of polypoidal choroidal vasculopathy (PCV) in Chinese patients.Methods The clinical data of 71 continuous patients (142 eyes) who were diagnosed with PCV by fundus photography, fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA) and optical coherence tomography (OCT) were analyzed retrospectively.Results Eleven patients (11 eyes) of 71 patients (142 eyes) were diagnosed with PCV to make up 15.49% and 7.75% of the numbers of patients and affected eyes respectivery. The patients included 7 males (63.6%)and 4 females (36.4%). The predominant location for these lesions was the macular region in 10 eyes (90.9%). Fundus examination demonstrated the reddish-orange nodular elevations in 6 eyes. ICGA revealed umbrellalike or twiglike branching vascular networks and polypoidal dilations at the vascular terminals of the branches in all patients, and feeder vassels within choroidal vascular networks were found in 8 eyes. OCT images of retinochoroidal structures showed prominent anterior protrusion of the orange subretinal mass corresponding to the polypoidal structure in the indocyanine green angiogram. An apparent discontinuity was observed in the highly reflective layer which delineates the polypoidal structure.Conclusions PCV mainly affects the male over 50 years and the eyes involved were mostly unilateral. Most of polypoidal vascular lesions are present in the macul ar area. (Chin J Ocul Fundus Dis，2003，19：269-332)