The Effect of Intravitreal Ranibizumab Injection on Retinal Nerve Fiber Layer Thickness and Optic Disc Parameters

Area of Science:

• Ophthalmology
• Retinal diseases
• Pharmacological treatments

Background:

• Macular edema secondary to age-related macular degeneration (AMD), diabetic macular edema (DME), and retinal vein occlusion (RVO) are leading causes of vision loss.
• Intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents, such as ranibizumab, are standard treatments for these conditions.
• The effects of ranibizumab on the retinal nerve fiber layer (RNFL) and optic disc parameters require further investigation.

Purpose of the Study:

• To evaluate the impact of intravitreal ranibizumab on RNFL thickness and optic disc parameters in patients with DME, AMD, and RVO.
• To compare changes in RNFL and optic disc metrics between different macular edema etiologies.
• To assess the consistency of findings between optical coherence tomography (OCT) and Heidelberg Retina Tomograph III (HRT-3) assessments.

Main Methods:

• Retrospective analysis of 60 patients receiving intravitreal ranibizumab (0.5 mg) for macular edema.
• Data collection included best-corrected visual acuity (BCVA), intraocular pressure (IOP), RNFL thickness, and optic disc parameters.
• Measurements were performed using OCT and HRT-3 at baseline and at multiple time points up to 6 months post-injection.

Main Results:

• Significant improvement in BCVA was observed across all patient groups.
• Mean RNFL thickness showed a significant reduction in the DME and RVO groups (p=0.0001 and p=0.043, respectively) as measured by OCT.
• No significant RNFL thinning was detected by HRT-3, and optic disc parameters showed variable, disease-specific changes.

Conclusions:

• Intravitreal ranibizumab treatment correlated with RNFL thinning in DME and RVO patients over six months, detectable by OCT.
• HRT-3 did not detect significant RNFL changes, and optic disc alterations were inconsistent and disease-specific.
• Findings are limited to non-glaucomatous eyes; further prospective studies are needed to understand long-term effects on the optic nerve.