Purpose
To describe a new finding on spectral optical coherence tomography (SOCT) in patients with Vogt-Koyanagi-Harada (VKH) and long-standing disease, the "choroidal bulging", believed to represent a sign of disease-related inflammation.
Methods
Retrospective review of clinical and imaging data from all eyes noted to have the “choroidal bulging” on SOCT performed as part of the follow-up protocol in an ongoing longitudinal VKH disease study, which is being conducted at the Uveitis Section, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil. The study protocol followed the statements of the Declaration of Helsinki, and was approved by local Institutional Review Board. Fundus photography was performed using a conventional fundus camera system. Angiographic studies (fluorescein,FA and indocyanine green, ICGA) and SOCT imaging were performed using Spectralis® HRA+OCT. For the SOCT evaluations, the “high-resolution” mode with the automatic real time (ART) mean module set at 25 frames and the AutoRescan® feature (i.e., automatic follow-up scan placement) were utilized.
Results
A localized thickening of the choroid that assumes a convex appearance with consequent bulging of the adjacent retina (i.e. “choroidal bulging") was identified in at least one follow-up visit in four eyes of three patients. A focal increase of the choroidal thickness of at least 40% as compared with the baseline was observed in all eyes at the bulging region. No retinal lesion was observed within the choroidal bulging region. Signs of ongoing disease-related inflammation/activity, such as anterior chamber cells on clinical exam and/or optic disc hyperfluorescence on FA were observed in all four eyes by the time choroidal bulging was identified. Furthermore, increased dark dots on ICGA ran in parallel to the appearance of choroidal bulging. Choroidal bulging resolved as these clinical or angiographical signs of disease-related inflammation/activity improved.
Conclusions
Although the diffuse thickening of the choroid has been described in several retinal diseases (including VKH), this is the first time that a localized increase in choroidal thickness has been described. We propose that this finding can be a new sign of disease-related activity in patients with VKH and long-standing disease. Choroidal bulging can be observed non-invasively and may help monitorizing VKH patients.
Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
746 uveitis-clinical/animal model •
452 choroid