Objective To observe the effect of panretinal photocoagulation (PRP) on the expression of cyclooxygenase-2 (COX-2), vascular endothelial cell growth factor (VEGF) in epiretinal membrane of proliferative diabetic retinopathy (PDR). Methods Atotal of 35 patients (35 eyes) with PDR and underwent plana vitrectomy were enrolled in this study. The patients were divided into non-PRP group (19 patients, 19 eyes) and PRP group (16 patients, 16 eyes) depends on if they had received PRP before surgery. The epiretinal membranes stripped during operation were collected for pathological examination. The histopathological features was observed by haematoxylin and eosin stain. The expression of CD34, COX-2 and VEGF, and microvessel density (MVD) were measured by immunohistochemistry method. Results Many new dispersed capillary blood vessels were found in the thick epiretinal membranes of non-PRP group, while scattered small blood vessels were found in the relatively thin epiretinal membranes of PRP group. MVD value was (7.42±1.39) in the non-PRP group and (4.56±1.22) in the PRP group, which was lower than the non-PRP group (t=6.41, P<0.01). The expression of CD34, COX-2 and VEGF in the tissues of epiretinal membrane in PRP group were obviously lower than the non-PRP group (t=6.147, 5.944, 7.445; P<0.01). Conclusion PRP can effectively inhibit the expression of COX-2 and VEGF in epiretinal membrane of PRP patients.
Objective To investigate the nature of the suprachoroidal fluid by detecting the concentration of total protein (TP), lactate dehydrogenase (LDH), albumin (ALB), total cholesterol (CHOL), total bilirubin (TBIL) in suprachoroidal liquid of patients who have rhegmatogenous retinal detachment with choroid detachment (RRDCD). Methods Eighteen RRDCD patients (18 eyes) who underwent vitrectomy were enrolled in this study. There were 10 males (10 eyes) and 8 females (8 eyes), 8 right eyes and 10 left eyes. There were 8 patients with age of ≤55 years, 10 patients with age of ＞55 years. There were 7 patients with duration of ≤30 days, 11 patients with duration of ＞30 days. There were 7 eyes with diopters of ≥−6.0 D, 11 eyes with diopters of ＜−6.0 D. There were 11 eyes with class C proliferative vitreoretinopathy (PVR), 7 eyes with class D PVR. Suprachoroidal fluid samples were collected from all the patients, and took preoperative serum samples as RRDCD group. Ten serum samples of normal people were set as control group. The concentration of TP, LDH, ALB, CHOL, TBIL in all the subjects were measured. The properties of the suprachoroidal fluid were identified by Light standard and concentration standard of ALB, CHOL, TBIL. Results There was no difference on the concentration of TP, LDH, ALB, CHOL, TBIL from suprachoroidal fluid samples in the patients with different age, sex, eyes, diopter, PVR grade (P＞0.05). There was no difference on the concentration of TP, LDH, ALB, CHOL, TBIL from preoperative serum samples in the patients between RRDCD group and control group (P＞0.05). There was no difference on the concentration of ALB and CHOL from suprachoroidal fluid samples and preoperative serum samples in the RRDCD patients (P＞0.05), but there were significant differences on the concentration of TP, LDH, TBIL (P＜0.05). According to the Light standard, there were 17 cases of exudates and 1 case of transudate. According to the concentration standard of ALB, CHOL and TBIL, there were 14, 18, and 16 cases of exudates, and 4, 0, and 2 cases of transudate, respectively. There was no difference on the identification result of Light standard and concentration standard of ALB, CHOL, TBIL (χ2=2.090, 1.029, 0.364; P＞0.05). Conclusion The suprachoroidal fluid of RRDCD patients composed of TP, LDH, CHOL and TBIL. The suprachoroidal fluid is more likely to be exudate.