Detection of macular photocoagulation scars with confocal infrared reflection imaging

Abstract

■ BACKGROUND AND OBJECTIVE: To study the diagnostic reliability (specificity and sensitivity) of confocal infrared reflection in detecting threshold argon laser photocoagulation scars in the macula. ■ PATIENTS AND METHODS: Fifty-six maculae with diabetic macular edema were evaluated by biomicroscopic slit-lamp fundus examination, digital color fundus photography, digital fundus fluorescein angiography, and digital infrared reflection images. Three examiners evaluated whether the eye had undergone any laser photopexy in the macula. ■ RESULTS: Sensitivity, specificity, and false-positive and false-negative results were calculated for each method. Fluorescein fundus angiography and infrared imaging, although using different approaches, both detect pigment epithelium changes such as laser scars. It seems that both methods are of equal specificity. On the other hand, both biomicroscopic fundus examination and digital color photography showed poor reliability. ■ CONCLUSION: Infrared reflection imaging is an easy, noninvasive method with excellent sensitivity and specificity in detecting photocoagulation scars from previous threshold laser treatment. It may be useful in estimating photocoagulated areas, especially if threshold treatment has been applied.