Italian researchers suggest two new biomarkers—ellipsoid zone reflectivity and the vessel density of the deep capillary plexus—may help clinicians assess the severity and progression of Best disease.  

Their study, published in the British Journal of Ophthalmology, evaluated the effects of neurovascular damage in patients with the typical vitelliform lesion of Best vitelliform macular dystrophy (BVMD) in the attempt to identify different progression patterns.

The prospective, observational case series enrolled 34 eyes of 24 patients who had the vitelliform stage of BVMD and 34 matched healthy controls. The researchers conducted complete ophthalmological exams on a yearly basis in both groups, including best-corrected visual acuity, biomicroscopy, OCT and OCT angiography (OCT-A).

At the follow-up, investigators found 12 eyes showed signs of stage progression. They also reported both the ellipsoid zone overlying the vitelliform lesion and the peri-lesional area showed a significant reduction in reflectivity when compared with the foveal and para-foveal ellipsoid zone of the controls. Additionally, the study reported vessel density decreased only at the deep capillary plexus.

The team also found that more extensive ellipsoid zone (reflectivity less than 0.7) and vascular alterations (vessel density less than 0.4) at baseline were strongly correlated with worse best-corrected visual acuity and more rapid progression at follow up.

As a result of these findings, rapid progressors may benefit the most from timely genetic therapies in the future, the researchers said.

Romano F, Arrigo A, Leone PP, et al. Altered ellipsoid zone reflectivity and deep capillary plexus rarefaction correlate with progression in Best disease. B J Ophthamol. July 29, 2019. [Epub ahead of print].