Long scleral tunnel technique for prevention of drainage tube-related complications during Ahmed glaucoma valve implantation.

To evaluate the safety and efficacy of modified Ahmed glaucoma valve (AGV) implantation (long scleral tunnel technique) in the treatment of neovascularization glaucoma (NVG). This retrospective observational case series included 23 patients (23 eyes) diagnosed with NVG secondary to proliferative diabetic retinopathy from January 2020 to June 2021. All 23 cases received anti-vascular endothelial growth factor treatment. Then, after 3 to 7 days, these cases were treated with modified AGV implantation (long scleral tunnel technique) and were followed up for at least 6 months. The best corrected visual acuity, intraocular pressure, numbers of antiglaucoma medications used, and postoperative complications were observed at 1 week and 1, 3, and 6 months after treatment. With treatment, the mean best corrected visual acuity improved significantly (P < .001) from 1.62 ±â€…0.52 logMAR preoperatively to 1.29 ±â€…0.36 logMAR at the 6-month follow-up. The mean postoperative intraocular pressure was significantly lower than that before modified AGV implantation during follow-up period, decreasing from 45.48 ±â€…7.86 mm Hg preoperatively to 14.87 ±â€…1.96 mm Hg at 1 week, 18.39 ±â€…2.25 mm Hg at 1 month, 16.61 ±â€…1.47 mm Hg at 3 months, and 17.48 ±â€…1.38 mm Hg at 6 months (F = 256.646, P < .001). The median number of antiglaucoma medications used by patients also significantly decreased from 3 (3-4) preoperatively to 0 (0-1) at the 6-month follow-up after surgery (Z = -4.248, P < .001). Postoperative complications included hyphema in 2 cases and vitreous hemorrhage in 1 case, and all 3 patients achieved satisfactory recovery with treatment. No drainage tube-related complications occurred among our patients. Long scleral tunnel technique is a safe and effective surgical treatment for NVG with fewer drainage tube-related complications.

Expression of peroxisome proliferator-activated receptor γ in rat retina during development.

AIM: To evaluate the spatiotemporal expression pattern of PPARγ in embryonic and early postnatal stages of rat retina. METHODS: Fetal rats were collected at 13-18d of gestation (GD) from pregnant females and postnatal rats at 1d (P1) and 5d (P5) after birth were also used. We used RT-PCR to detect PPARγ mRNA and immunohistochemical to observe PPARγ protein. And at last, we chose HE staining showed the structural changes of rat retina during development. RESULTS: RT-PCR analysis showed that PPARγ mRNA was expressed as early as GD13 and gradually decreased as maturation continued. However, the PPARγ gene expression significantly increased after birth, especially in P5. Immunohistochemical analysis showed PPARγ protein was expressed throughout the retinal neuroepithelium at GD13 and GD14, and then decreased during late embryogenesis but remained relatively high in the predicted ganglion cell zone. During postnatal development, PPARγ protein was remarkably increased and the positive signals were mainly located in nerve fiber layer (NFL), ganglion cell layer (GCL) and outer layers of the retina. CONCLUSION: The spatiotemporal changes of PPARγ expression demonstrated that PPARγ might play a role in regulating the differentiation and maturation of retinal cells.