Structural Changes of the Macula on Optical Coherence Tomography after Vitrectomy for Proliferative Diabetic Retinopathy

Abstract

Purpose: This study aimed to evaluate the relationship between macular structural changes and visual prognosis after pars plana vitrectomy (PPV) for proliferative diabetic retinopathy. Methods: The study included 60 eyes that had undergone PPV. Macular optical coherence tomography (OCT) findings were classified into 5 groups preoperatively and 10 groups postoperatively. Best-corrected visual acuity (BCVA) were analyzed according to pre- and postoperative OCT. Results: From the preoperative OCT, normal fovea with/without traction, normal fovea with preretinal hemorrhage, and tractional retinal detachment involving fovea showed an increase in BCVA after PPV (all p < 0.05). Normal fovea, epiretinal membrane and macular thickening were common after surgery. Normal fovea, epiretinal membrane and edema outside of the fovea showed good visual prognosis (BCVA >20/50). Subfoveal fibrosis, macular hole, loss of foveal depression, and serous foveal detachment showed poor visual prognosis (BCVA <20/100). Conclusion: Macular structural changes were various after PPV, and visual prognosis correlated with these changes.

Current management of diabetic tractional retinal detachments

“…Center point thickness correlates weakly with post-operative VA but integrity of the external limiting membrane and ellipsoid zone are strongly correlated. [ 105 106 107 108 ]…”

“…Post-operative epiretinal membranes (ERMs) are found in 21.7–52.8% of eyes despite extensive vitrectomies and numerous attempts to remove all vitreoretinal traction. [ 108 125 126 ] Risk factors for ERM formation after diabetic vitrectomy include active PDR, high-grade fibrovascular proliferation, post-operative hemorrhage, and residual fibrovascular stumps. [ 127 ] Vitreoschisis commonly occurs in eyes with TRDs,[ 128 129 ] making intraoperative identification and complete removal of the posterior hyaloid difficult.…”

“…[ 130 ] For this reason, more surgeons are routinely performing ILM removal during diabetic vitrectomies. [ 108 ]…”

The Effect of Internal Limiting Membrane Cleaning on Epiretinal Membrane Formation after Vitrectomy for Proliferative Diabetic Retinopathy

“…We only recorded ERM at 1 time point postoperatively, and results may have differed at other time points. ERM after vitrectomy has been shown to vary with the time postoperatively [32], but all the patients who required vitrectomy for ERM in the 12-month follow-up had clinically significant ERM at the 3-month time point. Late ERM formation significant enough to require vitrectomy would appear to be rare.…”

“…The presence of ERM after surgery for PDR has been widely reported with its prevalence ranging from 20 to 53% [31][32][33] relating to case mix and the methods of detection. We found that over 70% of our initial control group had some evidence of ERM on SDOCT 3 months after surgery, although this was only thought to be of clinical significance in 20%.…”