Preoperative and Intraoperative Administration of Intravitreal Avastin Only Transiently Inhibits Worsening of Diabetic Macular Edema Following Cataract Extraction

Abstract

Purpose: : Worsening of diabetic macular edema (DME) is well documented after cataract extraction (CE). Our study seeks to clarify both the efficacy and optimal timing of intravitreal Avastin (IVA) in this context.

Methods: : We performed a single-center retrospective review of patients with DME who also underwent CE between 2006 and 2010. Study inclusion criteria were documented visual acuity (VA) and Stratus OCT preoperatively and at 1 and 3 mo. postoperatively. Subjects were stratified into 3 groups: those receiving preoperative (within 1 mo. of surgery) IVA, those receiving intraoperative IVA (not treated with IVA in the 6 weeks prior to surgery), and a control group. Patients receiving treatments other than IVA within 3 mo. of surgery or any DME therapy during follow-up were excluded. The outcome measures were Δ logMAR VA, Δ central subfield thickness (CST), and Δ total macular volume (TMV) from baseline to 1 and 3 mo. postoperatively.

Results: : Of 184 eyes initially evaluated, a total of 88 eyes of 66 patients met the inclusion criteria (39 preop. IVA, 27 intraop. IVA, and 22 control eyes). There was no statistically significant difference in the preop. VA, CST, or TMV of the 3 groups. At 1 mo. postoperatively, the mean (95% CI) Δ CST for the preop. IVA group was +47 µm (+14 to +79 µm) vs. +133 µm (+71 to +195 µm) in controls (p = 0.02, student t-test) and +16 µm (-33 to +64 µm) in the intraop. IVA group (p = 0.30 vs. preop. IVA, 0.005 vs. controls). The mean Δ TMV for the preop. IVA group was +0.03 mm³ (-0.68 to +0.73 mm³) vs. +1.72 mm³ (+0.99 to +2.45 mm³) in controls (p = 0.002) and +0.14 mm³ (-0.43 to +0.71 mm³) in the intraop. IVA group (p = 0.80 vs. preop. IVA, 0.002 vs. controls). There was no statistically significant difference in Δ VA at 1 mo., or in Δ VA, Δ CST or Δ TMV at 3 mo.

Conclusions: : CST and TMV increase in patients with DME after CE. At 1 mo. postoperatively, there is a transient reduction in the magnitude of this increase in patients receiving preoperative and intraoperative IVA. This effect subsides within 3 mo. and does not correlate well with VA outcomes.

Keywords: diabetic retinopathy • cataract • macula/fovea