Imaging cystoid macular oedema secondary to branch retinal vein occlusion with spectral domain optical coherence tomography: A case report

Spectral domain optical coherence tomography has changed the way we view retinal diseases by providing us with high-resolution, cross-sectional images. It is very important for diagnosing and keeping a track of cystoid macular oedema, especially when it is caused by vascular conditions such as branch retinal vein occlusion. A 47-year-old man with poorly controlled type 2 diabetes mellitus presented with reduced visual acuity in his left eye. Amsler grid testing showed that the patient had metamorphopsia. The fundus examination indicated inferotemporal branch retinal vein occlusion, necessitating additional assessment. Spectral domain optical coherence tomography confirmed cystoid macular oedema with increased macula thickness and disruption of the external limiting membrane and ellipsoid zone, indicating disorganization of the outer retinal layers with photoreceptor involvement. There was also a partial posterior vitreous detachment. The changes in the outer retinal layers are important optical coherence tomography biomarkers that are linked to reduced visual acuity. The patient received an intravitreal injection of ranibizumab along with an adjunctive course of topical nepafenac (a nonsteroidal anti-inflammatory drug). During follow-up, spectral domain optical coherence tomography showed resolution of macular oedema, and the best-corrected visual acuity improved from 20/80 to 20/40, and the metamorphopsia was diminished. A small intraretinal cyst close to the fovea, hard exudates, and progressing posterior vitreous detachment were, however, seen. This case underscores the significance of systemic metabolic dysfunction, the prognostic utility of optical coherence tomography biomarkers, and the necessity of therapeutic strategies in the management of branch retinal vein occlusion.