Improved diagnosis of retinal laser injuries using near-infrared autofluorescence imaging

Abstract

Purpose : The incidence of retinal injuries secondary to handheld lasers is increasing due to wider availability. Conventional imaging may not fully identify or reveal the extent of such injuries. Near infrared autofluorescence (NIR-AF) is an imaging modality in which the autofluorescence signal largely arises from melanin in the retinal pigment epithelium and therefore may be beneficial in the diagnosis of laser damage.

Methods : 12 patients with handheld laser retinal injuries underwent assessment using fundus photography, optical coherence tomography (OCT), conventional blue autofluorescence (B-AF) and NIR-AF imaging.

Results : In all cases, characteristic lesions consistent with retinal laser injury were detected by NIR-AF imaging. The number and extent of lesions varied between patients and the distribution could be visualised using NIR-AF imaging. Findings using other imaging modalities were variable: on colour fundus photography these included a normal appearance or pigmentary changes and on OCT an ellipsoid zone interruption or outer nuclear layer changes. Few changes were evident on B-AF imaging. Other macular conditions, such as poppers retinopathy or solar maculopathy, which may have similar findings as laser damage on OCT imaging, have a different appearance on NIR-AF imaging.

Conclusions : Retinal laser injuries that may be missed using other imaging modalities can be detected by NIR-AF. This imaging modality provides a topographical view of the extent of laser injury with lesions having increased signal, most likely due to accumulation of melanin at the site of injury. We propose that NIR-AF should be included when investigating patients suspected of macular injury secondary to exposure to handheld lasers.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.