High-resolution optical coherence tomography in pigmented choroidal lesions.

Abstract

Purpose: Evaluating High-Resolution Optical Coherence Tomography (HR-OCT) versus standard spectral domain OCT in pigmented choroidal lesions.

Methods: We screened a total of 40 subjects with pigmented choroidal lesions. Lesions were imaged on HR-OCT and standard OCT devices with and without enhanced depth imaging (EDI) mode. Images were graded for qualitative and quantitative aspects, like choriocapillaris compression and width, choroidal reflectivity and thickness, amongst others.

Results: 32 of the 40 subjects could be included in the image analysis, the rest were excluded due to insufficient imaging. HR-OCT EDI mode allowed visualization of the posterior choroidal extent in 11 lesions (11/32 = 34.4%) versus in six (6/32; 18.8%), four (4/30; 13.3%), and five cases (5/30; 16.7%) in normal HR-OCT (n = 32), standard OCT (n = 30) and OCT EDI mode (n = 30), respectively, albeit not significantly different. Choriocapillaris compression was evident in 10 cases on HR-OCT and equally visible in all imaging modes. Mean choriocapillaris thickness ranged from 11.6 to 13.9 microns (SD range 3.84-4.33), and compressed choriocapillaris thickness similarly ranged from a mean of 7.1 to 7.8 microns (SD range 2.20-3.55). Image quality declined significantly towards the periphery in three out of four modes (p = 0.0077 to p = 0.29).

Conclusions: HR-OCT may provide better visibility of retinal and choroidal structures in pigmented choroidal lesions, although image quality is reduced in attempting to image peripheral lesions.

Translational relevance: The prototype HR-OCT offers insights into clinical features of pigmented choroidal lesions that are not apparent on conventional OCT imaging. This supports the development of HR-OCTolution OCT devices.