Vitrectomy for Diabetic Retinopathy Improved With Postoperative Injections

23G pars plana vitrectomy is a safe and effective treatment for patients with proliferative diabetic retinopathy (PDR), according to a case series observational study published in BMC Ophthalmology. Significant risk factors for postoperative low vision include intraoperative silicone oil filling and postoperative complications, while postoperative intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) is a protective factor for vision recovery, according to the report. 

Researchers evaluated 174 eyes from 127 patients (mean age, 57.4 years; age range 24-78 years; 64 men, 63 women) who underwent 23G pars plana vitrectomy for diabetic retinopathy at Taian City Central Hospital between December 2019 and November 2020. All participants completed at least 2 years of follow-up (mean follow-up time, 27.9 months). 

The preoperative best corrected visual acuity (BCVA) was less than 0.3 logarithm of the minimum angle of resolution (logMAR) in 89.7% of eyes and the postoperative BCVA was 0.3 or greater in 48.3% of eyes. Visual acuity improved in 83.3% of eyes. 

There was no change in 8.6% of eyes and 8.1% of eyes exhibited decreased visual acuity after pars plana vitrectomy for diabetic retinopathy. Average logMAR visual acuity was 1.5±0.7 prior to surgery and 0.7±0.6 following surgery, demonstrating significant improvement (P <.05). 

Logistic regression analysis revealed that intraoperative silicone oil filling and postoperative complications were significant risk factors for postoperative low vision. Preoperative and pseudophakic lens and postoperative intravitreal injection of anti-VEGF were protective factors for vision recovery (P <.05). 

The incidence of postoperative complications after pars plana vitrectomy for diabetic retinopathy was 15.5%. The most common complications were vitreous hemorrhage, neovascular glaucoma and traction retinal detachment, the report shows.

“Postoperative intra vitreal injection of anti-VEGF can assist in reducing macular edema, which leads to an improvement in vision, and it can also mitigate the ischemic and hypoxic state of the retina, thus attenuating the creation of retinal neovascularization,” the researchers explain. “As VEGF is a cytokine that plays a prominent role in neovascularization within the eye, elevated levels of VEGF may persist in the eyes of PDR patients even after PPV, which could contribute to an increased risk of PVH, NVG and other complications.”

This study was limited by not using a randomized controlled design.