Bacillary Detachment Identified in Significant Proportion of nAMD Eyes

Justis P. Ehlers, MD

New findings suggest that bacillary detachment is an optical coherence tomography (OCT) signature that is identifiable in a significant proportion of eyes with neovascular age-related macular degeneration (nAMD).

The research indicates that anti-vascular endothelial growth factor (anti-VEGF) therapy resulted in 100% resolution of bacillary detachment and significant decreases in central subfield thickness (CST) and subretinal hyper-reflective material (SHRM) volume.

However, investigators, led by Justis P. Ehlers, MD, Department of Ophthalmology, Cleveland Clinic, noted that improvement in visual acuity may have been limited by persistent ellipsoid zone (EZ) attenuation.

Ehlers and colleagues set out to evaluate the incidence of bacillary layer detachment among patients with nAMD and their response to anti-VEGF therapy. They did so in a post-hoc analysis of the OSPREY clinical trial. OSPREY was a prospective, double-masked, phase II study comparing brolucizumab 6-mg to aflibercept 2-mg over 56 weeks.

The analysis included individuals with treatment-naive nAMD at the initiation of the trial (n = 81). Investigators obtained spectral-domain OCT (SD-OCT) through 4-week intervals throughout the study period and these were segmented automatically using a proprietary, machine learning-enabled higher-order feature extraction platform.

Main outcomes for the trial included the presence of bacillary detachment. In these eyes, the effect of anti-VEGF therapy on chance from baseline in visual acuity, CST, retinal fluid volumes, SHRM volume, subretinal pigment epithelium (sub-RPE) fluid volume, and EZ integrity at week 56.

The findings report bacillary detachment was identified in 7.4% (6 of 81) eyes, which had higher fluid volumes, increased CST, EZ attenuation, and increased sub-RPE volume at baseline compared with eyes without bacillary detachment. Then, anti-VEGF treatment resulted in the resolution of bacillary detachment in 100% of the eyes.

Moreover, in eyes with bacillary detachment at baseline, the anti-VEGF treatment decreased CST, fluid burden, and SHRM volumes throughout the treatment course. However, the investigators noted there was no significant change from baseline in VA, sub-RPE volume, or EZ integrity throughout the 56-week course of anti-VEGF treatment.

The abstract, “Bacillary Detachment in Neovascular Age-Related Macular Degeneration: Incidence, Clinical Features, and Response to Anti-VEGF Therapy,” was published in Ophthalmology Retina.