GA Size, Progression Associated with CNV in Wet AMD

Large final geographic atrophy (GA) size may be associated with large choroidal neovascularization (CNV) size, according to data presented by Kerina Yang, BA, of VitreoRetinal Consultants in Brookline, MA, and colleagues and the American Academy of Ophthalmology 2020 Virtual meeting.

Additionally, large CNV networks were associated with greater GA progression, carrying implications for visual outcomes.

GA and CNV characteristics in patients receiving intravitreal injection treatment for age-related macular degeneration (AMD) have been reported in the past. In this study, the researchers looked at the correlation of size of GA as measured on en-face optical coherence tomography B (OCT-B) and size of the CNV on OCT-angiography study.

They identified 297 consecutive patients who had received intravitreal “treat and extend” anti-vascular endothelial growth factor (VEGF) injection treatments for wet AMD between October 2016 and October 2019 and analyzed OCT-B and OCT-A studies. After excluding certain patients, 157 eyes of 139 patients were included. The researchers correlated OCT-A and en-face images with OCT-B images and blood flow views to confirm structural details.

Of the 157 eyes, about half (49%) had an increase in GA through anti-VEGF treatment. Patients were classified as having mild (<0.75 mm2), moderate (0.75-1.8 mm2), or marked (1.8 mm2 or greater) increases.

About one-third of patients (32.5%) had mild increase in GA, with an average change in area of 0.31 mm2. About another third (35.1%) had moderate increase in GA, with average change in area of 1.21 mm2. The remaining third (32.5%) had marked increase, with an average change in area of 5.31 mm2.

Large final areas of GA—those measuring 3 mm2 or more—correlated with 50% of large CNVs at presentation. Large CNVs were associated with greater initial GA areas (2.00 mm2 compared with 0.97 mm2 for small CNV and 0.58 mm2 for medium CNV), with 88.2% experiencing significant progression of GA. However, there was no association between the number or frequency of anti-VEGF injections and GA progression.

The researchers also noted that 6.4% of eyes did not experience a change in their initial measurement of GA size, and 43.3% did not develop any GA through treatment. Interestingly, there were two eyes that appeared to have improvement in GA.

“Although a decrease in GA is rare, the two eyes were cases whether there was either patchy GA in the presence of shallow retinal pigment epithelium elevation or intraretinal and/or subretinal hyperreflectivity that made retinal pigment epithelium detail difficult to assess,” the authors noted.