OCT-angiography (OCT-A) may be able to detect neovascularization (NV) earlier than conventional B-scan OCT imaging in patients with neovascularization secondary to macular telangiectasia type 2 (MacTel), a study in the British Journal of Ophthalmology reports. The team of researchers also found OCT-A was more effective in tracking treatment results.

The retrospective analysis included 19 eyes of 17 patients with neovascularization  secondary to MacTel who were evaluated for approximately 13 months. During monthly intervals, patients underwent visual acuity testing, dilated funduscopy, spectral domain OCT and OCT-A. Eyes were treated with anti-VEGF following an as-needed treatment regime, and treatment decisions were based on morphological signs of activity as determined by B-scan OCT and funduscopy. Signs of neovascular activity were defined as an increase in retinal thickness, presence/increase of intraretinal/subretinal fluid and hemorrhages.

The researchers found that OCT-A allowed for the monitoring of both treatment effects and progression of neovascularization but not neovascular activity. Additionally, the growth of neovascular vessels was detectable in OCT-A images before signs of activity on OCT. Also of note: the investigators observed a progressive growth of neovascularization over time despite treatment, in addition to a preferential growth of neovascularization that extended within areas characterized by a focal reduction of choriocapillaris perfusion.

The investigators propose an adjustment of the current OCT-influenced as-needed treatment regime to prevent neovascularization progression and subsequent functional loss in neovascular MacTel patients.

Tzaridis S, Hess K, Friedlander M, Holz FG. Optical coherence tomography-angiography for monitoring neovascularisations in macular telangiectasia type 2. Br J Ophthalmol. June 8, 2020. [Epub ahead of print].