Interpretation of fundus autofluorescence changes in choriocapillaritis: a multi-modality imaging study

Area of Science:

• Ophthalmology
• Medical Imaging
• Retinal Diseases

Background:

• Primary inflammatory choriocapillaropathies (PICCPs) are a group of rare retinal disorders.
• Accurate diagnosis relies on characteristic imaging findings.

Purpose of the Study:

• To describe the imaging findings in PICCPs using fundus autofluorescence (FAF), fluorescein angiography (FA), indocyanine green angiography (ICGA), and spectral-domain optical coherence tomography (SD-OCT).
• To evaluate the effect of a photobleaching process on FAF imaging in PICCPs.

Main Methods:

• Retrospective review of six PICCP cases (four multiple evanescent white dot syndrome, two multifocal choroiditis).
• Multimodal imaging including FAF, FA, ICGA, and SD-OCT using Spectralis HRA.
• FAF imaging acquired under both dark-adapted and light-adapted conditions, including post-photobleaching.

Main Results:

• Active PICCPs showed increased FAF, which became isoautofluorescent after photobleaching.
• ICGA revealed hypofluorescent dark areas, particularly in the late phase, corresponding to FAF changes.
• SD-OCT demonstrated disruptions in the hyper-reflective ellipsoid zone layer.

Conclusions:

• FAF and SD-OCT are valuable complementary imaging techniques for assessing outer retinal alterations in PICCPs.
• Photobleaching alters FAF findings in PICCPs, providing additional diagnostic information.