Long-term outcomes of myopic choroidal neovascularisation treated with combined ranibizumab and dexamethasone characterised by multi-modal imaging

Aim To characterise the long-term outcomes of myopic choroidal neovascularisation (mCNV) treated with combined ranibizumab and dexamethasone, with the use of multi-modal imaging. Methods A retrospective study of 20 eyes with mCNV treated with intra-vitreal ranibizumab and dexamethasone on a treat-as-needed basis were followed up for a mean period of 47 months (range 19-81 months). Results The mean age was 55 +/- 16 years, with mean refractive error of -9.0 diopters. Subfoveal mCNV was seen in 11 eyes (52 %) and the others were juxtafoveal. At the final visit, 13 patients (65 %) had improvement, while four patients (20 %) had worsening in vision. The average number of ranibizumab and dexamethasone injections required was 3 +/- 1.7. There was a significant improvement in the mean visual acuity, reduction of the central retinal thickness, and an enlargement of the area of chorioretinal atrophy. The mean rate of increase in chorioretinal atrophy area was 0.05 +/- 0.09 mm(2)/month. Disruption of the photoreceptor layer, fragmentation of the retinal pigment epithelium, and breaks in the Bruch's membrane with a hyper-reflective lesion causing separation of the outer retinal layers were changes associated with active mCNV seen on optical coherence tomography (OCT). Conclusion Visual outcomes of mCNV treated with ranibizumab and dexamethasone on a treat-as-needed basis have favourable visual acuity outcomes. Using multi-modal imaging to monitor treatment response, chorioretinal atrophy, which may be related to visual function, should be used as an additional outcome measure to study the effect of combination treatment versus monotherapy.