Systemic Factors Influence the Prognosis of Diabetic Macular Edema after Pars Plana Vitrectomy with Internal Limiting Membrane Peeling

Abstract

Background: To evaluate the prognostic factors for the best-corrected visual acuity (BCVA) and foveal average retinal thickness after vitrectomy with internal limiting membrane (ILM) peeling for diabetic macular edema. Design: Retrospective, single-center study. Participants: This study involved 31 eyes of 27 patients who had undergone vitrectomy with ILM peeling between January 2005 and March 2008. Methods: Relationships between preoperative systemic or ocular factors and BCVA or foveal average retinal thickness before and 6 months after the operation were evaluated. Main Outcome Measures: BCVA and foveal average retinal thickness before and 6 months after the operation. Results: The mean logarithm of the minimum angle of resolution improved from 0.84 ± 0.64 (mean ± standard deviation) preoperatively to 0.64 ± 0.38 six months postoperatively (p = 0.393). Foveal average retinal thickness significantly improved from 473 ± 146 µm preoperatively to 318 ± 108 µm 6 months after the operation (p < 0.0001). Preoperative foveal average retinal thickness was significantly thicker with cardiovascular disease or cerebral infarction (p = 0.0019) or cystoid macular edema (p = 0.0028), while preoperative BCVA was significantly lower when an epiretinal membrane (p = 0.042) was present. Foveal average retinal thickness at the 6-month follow-up was significantly thicker when patients had a higher body mass index (p = 0.0088), were not on dialysis (p = 0.012), or did not have proliferative diabetic retinopathy (p = 0.013). BCVA at the 6-month follow-up was significantly lower in the group with no history of diabetes treatment until diabetic retinopathy was found (p = 0.023) and in patients with a higher preoperative glycosylated hemoglobin (p = 0.033). Conclusions: Preoperatively, BCVA and foveal average retinal thickness were primarily associated with ocular factors, while they were strongly associated with systemic factors, postoperatively. Ocular factor improvements may be related to the surgical procedure.

Effect of Internal Limiting Membrane Peeling on Long-Term Visual Outcomes for Diabetic Macular Edema

“…In particular, the HbA1c level can affect the resolution of edema after PPV with or without ILM peeling. 15,43,51,54 Thus, it is difficult to exclude effects of these systemic factors on visual outcome in comparative studies without a study design on bilateral DME. However, no previous studies used bilateral DME to compare between PPV with ILM peeling and PPV alone.…”

Macular ischemia and outcome of vitrectomy for diabetic macular edema

“…Several studies demonstrate the prognostic factors in eyes with DME when treated by vitrectomy [15,[20][21][22][23]. Various factors including systemic factors [15,23], baseline visual acuity [15,20,21], evidence of PDR [23], prior laser treatment [15], removal of the internal limiting membrane [20], vitreoretinal abnormalities [15,20,22] and retinal thickening [20,21] are reported to be associated with postoperative visual acuity and/or retinal thickness.…”

“…However, in this study, we were not able to find these factors as predictors of responsiveness to vitrectomy. The small number of cases [21][22][23], retrospective nature of the study [15,21,23], presence of vitreoretinal abnormalities and assessment of DME without OCT [15,20,22] may have affected the results of their analyses. The main difference of our cohort from those in the previous studies was that the majority of our cases (N = 60, 77.9 %) had been treated by an anti-VEGF agent, which is currently accepted as the mainstay of treatment for DME.…”

“…Factors associated with outcomes after vitrectomy in the eyes with DME are reported in previous studies [15,[20][21][22][23]. These results, however, cannot reflect the contemporary paradigm of DME management because study data included both tractional and nontractional DME or because the indications for vitrectomy were not limited to DME recalcitrant to primary anti-VEGF treatment.…”

Surgical Management of Diabetic Macular Edema

“…They also found that postoperative BCVA was significantly lower in patients without any diabetic treatment before the diagnosis of diabetic retinopathy. 66 These studies suggest that there are retinal, ocular, and systemic factors that can help identify patients who could benefit from surgical intervention for DME. ' …”