Widefield optical coherence tomography angiography for early detection and objective evaluation of proliferative diabetic retinopathy

Br J Ophthalmol. 2021 Jan;105(1):118-123. doi: 10.1136/bjophthalmol-2019-315365. Epub 2020 Mar 19.

Abstract

Purpose: To evaluate the utility of widefield optical coherence tomography angiography (WF-OCTA) compared with clinical examination in grading diabetic retinopathy in patients diagnosed clinically with proliferative diabetic retinopathy (PDR) or severe non-proliferative diabetic retinopathy (NPDR).

Design: This retrospective observational case series included patients diagnosed clinically with PDR or severe NPDR. Patients underwent standard clinical examination and WF-OCTA imaging (PLEX Elite 9000, Carl Zeiss Meditec AG) using 12×12 montage scans between August 2018 and January 2019. Two trained graders identified neovascularisation at the disc (NVD) and neovascularisation elsewhere (NVE) on WF-OCTA which were compared with the clinical examination, and to ultra-widefield fluorescein angiography (UWFA) when available.

Results: Seventy-nine eyes of 46 patients were evaluated. Of those, 57 eyes were diagnosed clinically with PDR, and 22 with severe NPDR. NVD was detected on OCTA-B scan as preretinal hyperreflective material (PRHM) in 39 eyes (100%) with evident flow signals in 79.5% compared with 51.3% detected clinically. We further classified NVD on OCTA into four subtypes and found that subtypes 1 and 2 could not be seen on clinical examination alone. WF-OCTA detected NVE in 81% of the cases compared with 55.7% detected clinically. Using WF-OCTA resulted in a higher percentage of PDR grading (88.6%) than on clinical examination (72.2%). When available, UWFA confirmed the WF-OCTA diagnosis in the majority of cases.

Conclusion: This study demonstrates that WF-OCTA has a higher detection rate of PDR than clinical examination. This suggests that this modality could be used non-invasively for the purpose of early detection and characterisation of neovascularisation.

Keywords: imaging; macula; neovascularisation; retina.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Diabetic Retinopathy / classification
  • Diabetic Retinopathy / diagnosis*
  • Early Diagnosis
  • Female
  • Fluorescein Angiography*
  • Humans
  • Male
  • Middle Aged
  • Optic Disk / blood supply*
  • Retinal Neovascularization / diagnosis*
  • Retinal Vessels / pathology*
  • Retrospective Studies
  • Tomography, Optical Coherence*