Intravitreal Ranibizumab for Diabetic Macular Edema Treatment in Phakic Vitrectomized Eyes

Abstract

Purpose: To show the effect of intravitreal ranibizumab injections in treating DME in phakic vitrectomized eyes versus pseudophakic vitrectomized eyes. Method: The medical records of 12 patients seen in the Retina Clinic and diagnosed to have DME were prospectively reviewed. The inclusion criteria were Phakic vitrectomized eyes. The exclusion criteria were pseudophkia and vitrectomized eyes with internal limiting membrane peeling. The main outcome measures included mean change in best corrected visual acuity (BCVA) from baseline, mean change in CMT, and mean number of 0.5 mg intravitreal ranibizumab injections administered during the follow up. Result: At baseline assessment, the mean (±SD) Logarithm of the Minimum Angle of Resolution (Log MAR visual acuity) was 0.71 (±0.56). At the 12 weeks, follow up assessment the mean Log MAR VA was significantly improved to 0.32 (±0.20), (p = 0.036). At baseline assessment, OCT was 390.75 (±51.40). The mean OCT at 4 weeks was significantly reduced to 353.83 (±49.49), (p = 0.019). Furthermore, at the 8 weeks follow up assessment, the mean OCT continued its significant trend of improvement to reach 341.08 (±60.24), (p = 0.016) and 294.42 (±57.27) in the 8 and 12 weeks follow up assessments respectively. Conclusion: In this small, prospective series, there was improvement in BCVA and CMT in the short-term after intravitreal Ranibizumab (IVR) for DME in previously phakic vitrectomized eyes. This may be attributable to a more remaining peripheral vitreous in phakic eyes behind the crystalline lens after vitrectomy which may clog the zonular area between anterior and posterior chambers and slowing down the antiVEGF clearance through the anterior chamber. Thus, vitreous works as a reservoir for anti-VEGF in phakic vitrectomized eyes comparing to pseudophakic vitrectomized eyes.