Spectral Domain Optical Coherence Tomography and Fundus Autofluorescence imaging of Posterior Segment Inflammatory Diseases

Abstract

Purpose: : To describe alterations in spectral domain optical coherence tomography (OCT) and fundus autofluorescence (FAF) imaging in patients with posterior segment inflammatory diseases (PSID) and to assess correlations between OCT and FAF parameters.

Methods: : This is a retrospective case series. Clinical records of patients with PSID in which OCT and FAF imaging had been performed were reviewed. Alterations in retinal tissue, third hyperreflective band and retinal pigment epithelium (RPE) were assessed on OCT and recorded. Pattern of autofluorescence in FAF was also recorded. Other clinical characteristics like inflammatory activity, position and size of the lesion were also assessed. Satistical tests used to assess correlations: Chi square, Fisher’s exact test and Kruskall-Wallis test.

Results: : Twenty seven lesions of 14 patients were included. Ethiology of PSID were: Serpinginous choroiditis (8 lesions), presumed Serpinginous-like choroiditis (3 lesions), Punctate inner choroidopathy (4 lesions), luetic choriorretinitis (2 lesions), toxoplasmosis (4 lesions), Multiple evanescent white dot syndrome (3 lesions), Idiopathic choriorretinitis (2 lesions), Leptospirosis (1 lesion). Seventeen lesions were considered active and 10 quiescent. Seventy four percent of lesions were extrafoveal and 25.9 % were foveal. In 48.1 % of the lesions the RPE was partially or completely absent. In 22.2 % of the lesions there was a thickening of the RPE. In 74.1% of the lesions the 3^rd hyperreflective band was partially or completely absent. Internal retinal tissue was normal in 63% of the cases. Fifty one percent of the lesions were hypofluorescent and 49 percent presented some degree of hyperautofluorescence. Hypofluorescent lesions were more frequently considered quiescent than active (79%) although just a statistical trend was observed in this correlation (p=0.08). Third hyperreflective band absence was not correlated with hypo or hyperfluorescence of the lesions.(p=0.404).

Conclusions: : In our series of PSID patients, structural alterations occurred mainly in external retina and RPE. Hypofluorescent lesions in FAF imaging are likely to mean quiescent disease. Third hyperreflective band absence was not correlated with hypo or hyperfluorescence of the lesions.

Keywords: uvea • imaging/image analysis: clinical • retinochoroiditis