Purpose: To assess the effect of a novel intense pulsed light (IPL) therapy on tear proteins and lipids in eyes with Meibomian gland dysfunction (MGD). Methods: Twenty-four eyes of 12 patients with MGD were recruited and received five overlapping flashes (565-1400 nm) directed at the lower eyelid. The IPL parameters include intensity: 2.5 to 6.5 J/cm 2 , voltage: 100 to 240 V, frequency: 50 to 60 Hz, input: 16 W, maximum optical energy: 23 J, pulse duration: <2.0 ms, and repetition time: 1-3.5 s. Tear samples were evaluated immediately before and 2 weeks after IPL therapy and included measurements of protein concentration, electrophoretic mobility by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, lipid profile assessments, and thin-layer chromatography (TLC) for phospholipids. Results: Significant improvements were observed in tear protein concentrations and molecular weight after IPL therapy. The most pronounced effect was in the molecular weight of tear lysozyme, lactoferrin, and albumin. Tear lipids showed an improvement in the concentrations of total lipids, triglycerides, cholesterol, and phospholipids. On TLC, the tears in patients with MGD had significantly lower amounts of anionic phosphatidylethanolamine, phosphatidylinositol, and phosphatidylserine but amounts zwitterionic neutral phospholipid phosphatidylcholine were normal. These anionic phospholipids showed obvious recovery after IPL therapy. Conclusion: IPL therapy is effective in eyes with MGD. It improved tear protein and lipid content and composition. The anionic phospholipids were more responsive to IPL therapy than were the other zwitterionic phospholipids.

This work aimed to consider the hazardous side effect of eye floaters treatment with Q-switched Nd:YAG laser on the protein and viscoelastic properties of the vitreous humor, and evaluate the protective role of vitamin C against laser photo disruption. Five groups of New Zealand rabbits were divided as follows: control group for (n = 3) without any treatment, the second group (n = 9) treated with Q-switched Nd:YAG laser energy of 5 mJ × 100 pulse delivered to the anterior, middle, and posterior vitreous, respectively (n = 3 for each). The third group (n = 9) received a daily dose of 25 mg/kg body weight vitamin C for 2 weeks, and then treated with laser as the previous group. The fourth group (n = 9) treated with 10 mJ 9 50 pulse delivered to the anterior, middle, and posterior vitreous, respectively (n = 3 rabbits each). The fifth group (n = 9) received a daily dose of 25 mg/kg body weight vitamin C for 2 weeks, and then treated with laser as the previous group. After 2 weeks of laser treatment, the protein content, refractive index (RI), and the rheological properties of vitreous humor, such as consistency, shear stress, and viscosity, were determined. The results showed that, the anterior vitreous group exposed to of 5 mJ × 100 pulse and/or supplemented with vitamin C, showed no obvious change. Furthermore, all other treated groups especially for mid-vitreous and posterior vitreous humor showed increase in the protein content, RI and the viscosity of vitreous humor. The flow index remained below unity indicating the non-Newtonian behavior of the vitreous humor. Application of Q-switched Nd:YAG laser should be restricted to the anterior vitreous humor to prevent the deleterious effect of laser on the gel state of the vitreous humor.

Purpose: To evaluate the effects of low-level laser therapy (LLLT) on the retina with diabetic retinopathy (DR). Methods: Eight Wistar rats were used as a control group, and 64 rats were injected intraperitoneally with 55 mg/kg of streptozotocin to induce diabetes and served as a diabetic group. After the establishment of the DR, the rats were separated into (a) 32 rats with DR; did not receive any treatment, (b) 32 rats with DR were exposed to 670 nm LLLT for 6 successive weeks (2 sessions/week). The retinal protein was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, total antioxidant capacity (TAC), hydrogen peroxide (H 2 O 2 ), and histological examination. Results: LLLT improved retinal proteins such as neurofilament (NF) proteins (200 KDa, 160 KDa, and 86 KDa), neuron-specific enolase (NSE) (46 KDa). Moreover, the percentage changes in TAC were 46.8% ( P < 0.001), 14.5% ( P < 0.01), 4.8% and 1.6% ( P > 0.05), and in H 2 O 2, they were 30% ( P < 0.001), 25% ( P < 0.001), 20% ( P < 0.01), and 5% ( P > 0.05) after 1, 2, 4, and 6 weeks, compared with the control. DR displayed swelling and disorganization in the retinal ganglion cells (RGCs) and photoreceptors, congestion of the capillaries in the nerve fiber layer, thickening of the endothelial cells’ capillaries, and edema of the outer segment of the photoreceptors layer. The improvement of the retinal structure was achieved after LLLT. Conclusion: LLLT could modulate retinal proteins such as NSE and NFs, improve the RGCs, photoreceptors, and reduce the oxidative stress that originated in the retina from diabetes-induced DR.

Abstract. The aim of the present study was to evaluate the change in corneal protein and oxidative stress state after using photodynamic therapy (PDT) for treatment of experimental corneal neovascularization (NV) with benzoporphyrin derivative (BPD). One group was considered as control (N = 10 eyes), corneal NV was induced in 25 New Zealand male rabbits (N = 50 eyes) after placing silk sutures in the corneal limbus. Five rabbits with corneal NV were left without any treatment, and 20 rabbits were administered by intravenous injection with Verteporfin at a dose of 1.5 mg/kg. Diode laser (660 nm) was applied for 5 minutes with a power of 50 mW/cm 2 . For a period of 4 weeks, five rabbits were selected and sacrificed weekly (N = 10 eyes each). The corneas were isolated for determination of protein content, SDS-PAGE, total antioxidant capacity (TAC), total oxidative capacity (TOC), malondialdhyde (MDA) and oxidative stress index (OSI). The results indicated that corneal NV induced changes in the content and composition on the corneal protein and gradual improvement of the cornea after the 3 rd and 4 th week of PDT was detected. Furthermore, the oxidative/antioxidative balance shifted towards the antioxidative status that helped to prevent further damage.

Introduction: The efficacy of many therapeutics techniques for treatment of branch retinal vein occlusion (BRVO) has been the subject of many investigations. The aim of the present work is to evaluate the transluminal Nd: YAG laser thrombolysis as a new therapeutic approach used for treatment of BRVO in rabbits as an experimental model. Methods: Four rabbits were considered as a control (n=8 eyes); occlusion of the branch retinal veins was performed by using a dye enhancing thrombus formation in right eyes of 10 rabbits (n=10 eyes). Thrombi in the retinal veins were induced by intravenous injection of rose bengal solution as a photosensitizer immediately before the argon laser application with a power of 1200 mW, a spot size of 100 µm, and a duration of 20 ms. One week later, transluminal Nd: YAG laser thrombolysis (30 mJ, 3 pulses/4 ns) was employed to the site of occluded veins, until the thrombi were partially or completely shattered. The rabbits were followed up after 4 days, 1 week and 2 weeks for slit lamp fundus examination and the treated retinas were isolated for histopathological examination. Results: Argon laser photothrombosis induced complete BRVO with some vitreous hemorrhage, destruction, and necrosis in the surrounding retinal layers. Moreover, one week later, Nd: YAG laser thrombolysis showed complete venous flow, minimal vitreous hemorrhage, reperfused retina, complete veins improvement. Follow up after 2 weeks revealed more improvement of all retinal layers. Conclusion: Treatment with transluminal Nd: YAG laser thrombolysis represented a novel therapeutic modality in BRVO.