A team of researchers from Ohio suggests subfoveal choroidal thickness (SFCT) in patients with exudative age-related macular degeneration (AMD) may be an important prognostic tool in determining treatment burden, with higher SFCT requiring more intravitreal injections.

This retrospective study evaluated 62 treatment-naive patients with exudative AMD who were treated with treat-and-extend or PRN anti-VEGF protocols. The researchers measured SFCT at three locations (the foveal center and 500µm nasal and temporal to the fovea) using optical coherence tomography (OCT) at presentation and at three, six and 12 months. They then recorded and analyzed demographic characteristics, OCT imaging biomarkers and visual acuity (VA).

At baseline, the team found that the average SFCT was 187µm, which decreased to 175µm at three months and 173µm at 12. They note that the average number of injections at 12 months was 6.6, and a higher SFCT at baseline showed a statistically significant correlation with a larger number of intravitreal injections at 12 months. The researchers add that eyes with SFCTs greater than one standard deviation above the average required 50% more injections than others.

The study notes that there was no association between SFCT at baseline and VA at 12 months, and there was no correlation between baseline SFCT and the presence of subretinal fluid, intraretinal fluid or subretinal hyper-reflective material at baseline.

Kumar JB, Wai KM, Ehlers JP, et al. Subfoveal choroidal thickness as a prognostic factor in exudative age-related macular degeneration. Br J Ophthalmol. August 27, 2018. [Epub ahead of print].