Multimodal Imaging Enhanced by Indocyanine Green Angiography in Syphilitic Uveitis

To systematically characterize fundus changes associated with syphilitic uveitis(SU) on multimodal imaging(MMI) enhanced by indocyanine green angiography(ICGA).

A prospective, non-comparative investigation included SU patients from 2018 to 2019 (24 patients), along with 8 from a previous pilot (2015-2017).MMI included ICGA, fluorescein angiography(FA), autofluorescence(FAF), and spectral domain optical coherence tomography (SD-OCT) at admission, discharge, and late follow-up.

Analysis covered 62 eyes of 32 patients (78% men; mean age 43). MMI was superior to ophthalmological examination for identification of laterality and involvement of posterior segment, identifying subclinical inflammation in five eyes of five patients(15.6%) otherwise classified as having unilateral uveitis, recognizing posterior segment inflammation not identified in 11 eyes (17.8%), and improving the anatomical classification of uveitis in 19% (11/57 eyes).ICGA disclosed geographical choroidal hypofluorescence, hypofluorescent dark dots (HDD) and speckled hypofluorescence respectively in 47% (27/57), 72% (33/46) and 93% (52/56) of study eyes with sufficiently transparent media. On FA, placoid hyperfluorescence was identified in 30% (16/54) eyes/ 42% (13/31) patients and a speckled distribution of fluorescein (named punctiform) was found in 33% (18/54) eyes/ 45% (14/31) patients. Interruptions of external limiting membrane (ELM) on SD-OCT were predictive of worse BCVA at presentation and subfoveal choroidal thickness>350 micrometers on SD-OCT was predictive of worst outcome after treatment.

ICGA-enhanced MMI has a major role in detection/localization of intraocular inflammation associated with SU, disclosing the choroid as primary site of inflammatory involvement. Choroidal hypofluorescence was the most common abnormality, and ELM disruption was associated with poor BCVA before and after treatment.