Abstract
Purpose :
Optical coherence tomography angiography (OCTA) is a non-invasive imaging modality that provides high-resolution retinal and choroidal vascular imaging without dye injection. Notably, however, the role of OCTA for choroidal neovascularization (CNV) detection in nAMD remains unclear. The current study investigated the CNV detection rate by OCTA in comparison with standard fluorescein angiography (FA) and optical coherence tomography (OCT).
Methods :
This retrospective study included 51 eyes from 45 treatment naïve patients (mean age: 82.8 ± 7.7 years) diagnosed with nAMD by two retinal imaging experts using a multimodal imaging protocol. All patients underwent FA (Zeiss FF4 or Heidelberg), spectral domain OCT (SD-OCT), and OCTA imaging (Spectalis Heidelberg, Heidelberg Engineering, Germany). OCT and FA detection rates were measured and compared to that of autosegmented OCTA. Segmentation errors were manually corrected.
Results :
CNV was classified into the 3 subtypes including: 20% type 1, 73% type 2, 5% combined type 1 and 2, and 5% type 3. As shown in Table 1, the overall CNV detection rate by OCT, FA, and autosegmented OCTA were 86%, 83%, and 71%, respectively. Type 1 CNV detection rates were 90%, 70%, and 60%, respectively. Type 2 CNV detection rates were 84%, 85%, and 81%, respectively. Combined type 1 and 2 CNV detection rates were 100%, 100%, and 0%, respectively. Type 3 CNV detection rates were 100%, 100%, and 0%, respectively. Manual segmentation increased overall CNV detection rate, ranging between 82 to 88% depending on the grader. In addition, type 1, 2, and 3 CNV detection rates increased, ranging between 90 to 100%, 89 to 92%, and 0 to 50%, respectively.
Conclusions :
CNV detection by OCTA was highest for type 1 and type 2 CNV, while detection of combined type 1 and 2, and type 3 CNV was less accurate. Manual resegmentation improved CNV detection rates, especially for type 1 and type 2 CNV, exceeding that of OCT and FA. Notably, this increase in CNV detection rate was shown to be operator dependent, indicating some of the challenges in interpreting OCTA, similar to OCT and FA. This study provides valuable insights into the diagnostic utility of OCTA in nAMD as a non-invasive, adjunctive tool in nAMD.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.