Purpose: To describe the in-vivo pathology of indirect choroidal rupture (ICR) in patients with recent ocular trauma using swept-source optical coherence tomography (SSOCT).
Methods: Retrospective observational study of the presenting and follow-up OCT images of four consecutive Asian patients with blunt trauma presenting over a period of 6 months and review of OCT descriptions in the literature.
Results: The three patients who presented within 2 weeks of injury showed a gap in the Bruch's membrane (BM)/retinal pigment epithelial complex at the site of the ICR. The distance of the gap ranged from 103 to 465 μm. Blood from associated tear in the choriocapillary layer dissected under the photoreceptor layer to lift it off the retinal pigment epithelium (RPE) layer. The Sattler's and Haller's layers of the choroid were not affected. Fibro-vascular proliferation occurring in the reparative phase bridges the gap in the BM, RPE complex. Late fibrous tissue proliferation extends into the Sattler's layer in the choroid and goes up to the outer nuclear layer in the retina disrupting its architecture.
Conclusion: SSOCT is a useful tool to study the pathology of recent onset ICR as it is capable of imaging through blood. The primary injury in ICR seems to be a break in the Bruch's membrane. The RPE layer and choriocapillaries get disrupted secondary to the break in the BM as their basement membranes are part of the BM. Scarring during the reparative phase disrupts the adjacent layers of the choroid and retina.
Keywords: Blunt eye trauma; Bruch's membrane breaks; choroidal rupture; sub-macular bleed.