SS-OCT Angiography Imaging of Geographic Atrophy
Ophthalmology Retina, February 2019
Thulliez et al. used two different swept-source optical coherence tomography angiography (SS-OCTA) scanning patterns to image geographic atrophy (GA), with the goal of determining whether the patterns provided similar measurements in eyes affected by age-related macular degeneration (AMD). They found that the two patterns strongly correlated on measurements of area and enlargement rate (ER), and they suggest that all macular GA can now be imaged with 12 × 12 mm SS-OCTA scans, which provide a 40-degree field of view (FOV).
For this prospective case series, the researchers enrolled 25 patients (32 eyes) with GA secondary to dry AMD. They compared the area and ER measurements obtained when the same GA lesion was imaged using 6 × 6 mm and 12 × 12 mm scan patterns on the same SS-OCTA machine. Images were obtained at baseline and at the six-and 12-month marks—and at baseline, the atrophic lesions had to be fully contained within the 6 × 6 mm scan pattern.
The results showed that lesion area and ER measurements for both scan patterns were comparable for all eyes in all patients through the 12 months of the study. As a result, the researchers said, the 12 × 12 mm SS-OCTA scans can now be considered the ideal single imaging modality for the detection and follow-up of GA, as they provide a wider FOV and provide information on both structure and flow. The researchers cautioned, however, that it is not possible to assess hyperautofluorescence patterns at the margins of GA with this technology.
The original article can be found here.