Outer Retinal Tubulation in Geographic Atrophy

Area of Science:

• Ophthalmology
• Medical Imaging
• Retinal Diseases

Background:

• Outer retinal tubulation (ORT) is a finding on optical coherence tomography (OCT) in patients with geographic atrophy (GA).
• The clinical significance of ORT in GA progression remains unclear.

Purpose of the Study:

• To determine the prevalence of ORT in eyes with GA.
• To investigate the association between ORT and the rate of GA lesion growth.

Main Methods:

• A post hoc longitudinal analysis of 62 eyes from the FILLY trial (sham treatment group).
• ORT prevalence was assessed at baseline, 12 months, and 18 months.
• GA lesion growth rate was calculated from baseline to 18 months.

Main Results:

• ORT prevalence was 24% at baseline, increasing to 43% at 12 and 18 months.
• Eyes with ORT at baseline exhibited slower mean GA lesion growth.
• This association was consistent across overall, subfoveal, and nonsubfoveal GA subgroups.

Conclusions:

• ORT may signify a slower-progressing phenotype of geographic atrophy.
• The presence of ORT appears to be an independent indicator of GA lesion growth rate, irrespective of foveal involvement.