Retinal Morphology and Retinal Nerve Fibres Layer Changes After Intravitreal Ranibizumab for Exudative AMD: Nine Months-Prospective Study

Abstract

Purpose: : To evaluate changes on visual acuity, retinal morphology and RNFL (Retinal Nerve Fiber Layer) thickness in patients receiving multiple intravitreal injections of ranibizumab for exudative AMD.

Methods: : In this prospective study we included 21 eyes of 21 consecutive patients with active CNV for AMD. All patients were treated with a loading-dose of 3 intravitreal injections of ranibizumab (2,3 mg/0,23 ml) one every 30 days and then as needed according to visual acuity and OCT evaluations. We performed a complete ophthalmological examination, including visual acuity, OCT (macula and glaucoma protocol) and GDx-VCC examinations to analyze macular and RNFL thickness at baseline and during follow up at month 1, 3, 6 and 9.

Results: : Mean LogMAR visual acuity at baseline was 0.418±0.169, at month 9 was 0.304±0.127. Mean central macular thickness at baseline was 379.33±148.06 µm; at month 9 we measured a mean decrease of-210±163.53µm (p<0.05). Mean RNFL (obtained from OCT evaluations) at baseline was 110.6±9.605µm; at month 9 we measured a mean decrease of -3.2±3.55µm (p>0.05). Mean RNFL thickness obtained from GDx-VCC protocol at baseline was 61.18±6.18µm; at month 9 we measured a mean decrease of -5.657±4.194 µm (p>0.05).

Conclusions: : Both OCT and GDx measurements showed a non statistical significative variation on retinal nerve fibre layer thickness during the follow up. This suggests that the frequent IOP fluctuations after intravitreal treatments as well as anti-VEGF properties of ranibizumab inhibiting neuroprotection do not cause adverse effects on retinal ganglion cells on one year follow up. Moreover, our study confirm the efficacy of ranibizumab to improve visual acuity modifying the worsening evolution of exudative AMD and restoring retinal layers thickness-morphology on treated patients.

Keywords: age-related macular degeneration • imaging/image analysis: clinical • ganglion cells