Imaging choroidal neovascular membrane using en face swept-source optical coherence tomography angiography

Area of Science:

• Ophthalmology
• Medical Imaging
• Vascular Biology

Background:

• Choroidal neovascular membrane (CNV) is a leading cause of vision loss.
• Accurate imaging of CNV morphology is crucial for diagnosis and treatment.
• Traditional methods like fundus fluorescein angiography (FFA) have limitations, including dye injection and potential for inconclusive results.

Purpose of the Study:

• To evaluate the efficacy of swept-source optical coherence tomography angiography (SS-OCTA) in delineating choroidal neovascular membrane (CNV) morphology.
• To compare SS-OCTA findings with traditional imaging modalities such as FFA and SS-OCT.
• To assess the role of SS-OCTA as a risk-free alternative for CNV imaging.

Main Methods:

• Retrospective observational case series of 105 patients (136 eyes) with CNV.
• Review of clinical data, FFA, SS-OCT, and SS-OCTA images.
• Utilized SS-OCTA's deeper penetration and higher resolution, along with its blood flow detection algorithm (OCTARA) for in vivo CNV visualization without dye.

Main Results:

• SS-OCTA revealed distinct features for active CNV (increased capillary density, arborization, anastomosis, looping, peri-lesional hollow) and inactive CNV (decreased density, large linear vessels, feeder vessels).
• A 97% concordance was found between SS-OCTA, FFA, and SS-OCT findings.
• In 3% of cases, SS-OCTA accurately ruled out CNV where FFA/SS-OCT were inconclusive or false-positive.

Conclusions:

• SS-OCT and SS-OCTA are reproducible, risk-free analogs to FFA for imaging CNV.
• SS-OCTA is particularly valuable and versatile in diagnosing CNV when FFA and SS-OCT provide inconclusive results.
• SS-OCTA offers a safe and effective method for detailed CNV morphology assessment.