Evaluation of Pro-re-Nata (PRN) and Treat and Extend Bevacizumab treatment protocols in Sorsby Fundus Dystrophy

Abstract

Purpose: To describe long-term outcomes with intravitreal Bevacizumab for choroidal neovascularization secondary to Sorsby fundus dystrophy.

Materials/methods: Observational case series.

Results: Two sisters of the same family formally diagnosed with Sorsby fundus dystrophy were followed-up for 12 years. The elder sister (S1) presented with significant decline in vision due to choroidal neovascularization in her right eye (OD). She developed choroidal neovascularization 3 years later in her left eye (OS). She was treated with Bevacizumab intravitreal injections on a on a pro-re-nata (PRN) until April 2015, when a treat-and-extend (T&E) approach was adopted. Best corrected visual acuities at the time of switch to T&E were 1.09 OD and 0.85 LogMar OS. Best corrected visual acuities at the last follow-up were LogMar 1.1 OD and 0.82 OS. Her younger sister (S2) presented with best corrected visual acuities of LogMar 0.1 OD and 0.0 OS. She developed choroidal neovascularization 5 years later in both eyes. OS developed choroidal neovascularization 18 months after her right eye. She received Bevacizumab on a pro re nata basis until April 2015 when a switch to a T&E was performed. Best corrected visual acuity in the left eye at the switch to T&E was 0.34 LogMar. At the last follow-up, best corrected visual acuities were LogMar 1.2 OD and 0.29 OS.

Conclusion: Bevacizumab is an effective therapy for choroidal neovascularization secondary to Sorsby fundus dystrophy. A T&E protocol appears more effective compared to pro re nata protocol in minimizing recurrence of choroidal neovascularization with potential secondary scar formation or atrophy.

Keywords: Best corrected visual acuity; OCT-angiography; Sorsby fundus dystrophy; choroidal neovascular membrane; tissue inhibitor metalloproteinase-3; vascular endothelial growth factor.