Researchers recently found that swept-source OCT-derived 3D volumetric imaging is a reliable and accurate predictor of primary angle-closure glaucoma outcome.

The single-center, longitudinal study included 90 eyes of 81 patients with primary angle-closure disease who underwent laser peripheral iridotomy. Patients were imaged with swept-source OCT before the procedure and one week, one month, three months, six months and one year after.

Elevated pressures were observed in 14 patients. The researchers found that mean trabecular-iris space area 750μm (TISA750) from the scleral spur was negatively associated with IOP elevation. This correlation varied across quadrants, with the only significant association detected in the temporal TISA750 quadrant. A greater anterior chamber volume was associated with a lower risk of IOP elevation. Iris volume was not associated with elevated IOP.

The study authors concluded that 3D visualization yields more robust parameters for glaucoma monitoring and that anterior chamber volume is a more effective marker than TISA750. While TISA750 varied from quadrant to quadrant because angle profiles change from meridian to meridian, they noted, “anterior chamber volume represents the anterior chamber as a whole, making it resilient to such error. It is also superior to angle width parameters in the differentiation of narrow angle from open angle.”