Morphological patterns of indirect choroidal rupture on spectral domain optical coherence tomography

Unnikrishnan Nair,¹ Manoj Soman,¹ Sunil Ganekal,² Vaishnavi Batmanabane,¹ KGR Nair<sup>1

1</sup>Chaithanya Eye Hospital and Research Institute, Trivandrum, Kerala, ²Nayana Super Specialty Eye Hospital and Research Center, Davangere, Karnataka, India

Purpose: To evaluate the morphological types of indirect choroidal rupture (ICR) using spectral domain optical coherence tomography (SD-OCT).
Methods: This was a prospective interventional study of 18 eyes of 18 patients who presented with a history of blunt ocular trauma resulting in choroidal rupture. All patients underwent detailed ophthalmic evaluation and SD-OCT examination.
Results: Mean age of the patients was 32±9.6 years. Morphologically, two types of choroidal rupture were seen on SD-OCT. The first type seen (Type 1 ICR) was a forward protrusion of the retinal pigment epithelium-choriocapillaris (RPE-CC) layer with an acutely angled pyramid or dome shape. This was associated with either a small loss of continuity of the retinal pigment epithelium layer or elevated RPE-CC projection accompanied by a significant quantity of subretinal hemorrhage. The second type observed (Type 2 ICR) was a larger area of disruption of the RPE-CC layer, photoreceptor inner segment/outer segment junction, and external limiting membrane, with a posteriorly directed concave contour depression at that area and downward sliding of tissues into the defect. At presentation, ten eyes were observed to have Type 1 ICR and eight to have Type 2 ICR. Of the 18 eyes, one with Type 1 ICR and two with Type 2 ICR developed choroidal neovascularization (16.6%).
Conclusion: Two distinct tomographic patterns of choroidal ruptures were identified on SD-OCT, which may allow ruptures to be classified into two morphological types. There are morphometric and clinical differences between the two types, which may help to prognosticate visual outcome and anticipate complications following choroidal ruptures.

Keywords: SD-OCT, ICR, blunt ocular trauma, choroidal neovascularization

A Letter to the Editor has been received and published for this article.