Biomarkers of optical coherence tomography in evaluating the treatment outcomes of neovascular age-related macular degeneration: a real-world study

Abstract

This study evaluated the characteristic changes in optical coherence tomography (OCT) biomarkers in neovascular age-related macular degeneration (nAMD) treated with anti-vascular endothelial growth factor drugs and their relationship with visual outcomes at 1-year follow-up in a real-world setting. We retrospectively reviewed the medical records of 126 eyes with nAMD treated with either intravitreal ranibizumab or aflibercept, including ophthalmologic examinations and spectral-domain OCT at baseline and months 3, 6, and 12 after first injection. Treatment response of intraretinal cysts (IRCs), subretinal fluid (SRF), and pigment epithelial detachment (PED), and the correlation between best-corrected visual acuity (BCVA) changes and these OCT biomarkers were analyzed. After an average of 5.1 ± 1.5 injections, 33.3% of eyes with PED showed resolution at month 12, a significantly lower proportion than for IRCs (53.8%) or SRF (51.6%). BCVA improvement at 1 year was negatively associated with PED at baseline and with IRCs or PED at month 12. Persistence of IRCs at month 12 was associated with degeneration morphology of IRCs at baseline and non-resolved cysts at month 3 after loading. In conclusions, IRCs and PED are associated with poor visual improvement in nAMD in a real-world setting. Both IRCs and SRF responded better than PED to anti-VEGF therapy.

Figure 1

Mean best-corrected visual acuity (BCVA) and central foveal thickness (CFT) at each time point. There were no statistical differences in BCVA between any time points including baseline and months 3, 6, and 12 (P > 0.05 for all). The CFT values at months 3, 6, and 12 were significantly less than the baseline value (P < 0.001 for all), but the values did not differ between any pair of post-treatment time points (P > 0.05 for all).

Figure 2

Relationship between optical coherence tomographic (OCT) biomarkers and visual acuity response at each time point. Each OCT biomarker was classified as present or absent at each time point. The treatment response was classified into 3 groups according to the change in logMAR visual acuity: gain (≤−0.2), unchanged (≤0 to >−0.2), and lost (no improvement, >0). (Top) A significant difference in treatment response was found between patients with and without intraretinal cysts (IRCs) at months 3 and 12, but not at month 6. (Middle) No significant differences was found in treatment response at any time point corresponding to presence or absence of subretinal fluid (SRF). (Bottom) The group of patients with pigment epithelial detachment (PED) at month 12 included significantly more cases with lost vision and fewer with unchanged compared with the group without PED, but no differences were found at months 3 or 6.

Figure 3

Flowchart illustrating the changes in presence of intraretinal cysts (IRCs) in neovascular age-related macular degeneration patients presenting with IRCs at baseline using 2 checkpoints: the morphology of the cyst at baseline and the response of the IRC at month 3. OCT: optical coherence tomography.

Figure 4

Comparison of best-corrected visual acuity (BCVA) changes from baseline at different time points, split according to treatment response at month 3. The patients were divided into 3 groups according to the BCVA change at Month 3: strong improvement (change in logMAR BCVA ≤−0.2), limited improvement (change in logMAR BCVA ≤0 to >−0.2), and no improvement (change in logMAR BCVA >0). At months 3, 6, and 12 the BCVA improvement was significantly better in the strong improvement group than in the limited improvement group, and both were significantly better than in the no-improvement group (P < 0.001 for all comparisons).

Figure 5

Optical coherence tomography (OCT) images of different types of morphology of intraretinal cysts (IRCs) in age-related macular degeneration. (Top) OCT image showing degenerative morphology of an IRC (arrowhead) with square-shaped contour and alteration of underlying retinal pigment epithelium. (Middle) Another example of degenerative morphology of IRCs (arrowheads) on OCT, demonstrating a small cyst without obvious expansion of the adjacent layered retinal structure (arrowhead on the right) and an IRC with square-shaped contour (arrowhead on the left). (Bottom) Example of exudative IRCs on OCT, showing large cysts along with stretched adjacent retinal tissue and normal retinal pigment epithelium.