Anterior segment optical coherence tomography in the assessment of optical density and heterogeneity of the trabecular meshwork and perilimbal sclera in open-angle glaucoma

PURPOSE. To study the optical density and heterogeneity of perilimbal sclera and trabecular meshwork in individuals with and without open-angle glaucoma.

METHODS. The study included 49 patients (89 eyes), divided into two groups: the study group (45 eyes with open-angle glaucoma stages I–IV) and the control group (44 eyes without glaucoma). All patients underwent standard ophthalmological examinations recommended for glaucoma, as well as anterior chamber angle scanning in four quadrants using anterior segment optical coherence tomography (OCT). Parameters of optical density and heterogeneity of the perilimbal sclera and trabecular meshwork were analyzed.

RESULTS. In the study group, the optical density of the trabecular meshwork was higher in the inferior quadrant than in the control group, with a positive correlation to intraocular pressure (IOP).

The study group also exhibited lower heterogeneity of the perilimbal sclera in the temporal quadrant compared to the control group. A trend toward reduced optical density in the inferior quadrant as glaucoma stage progressed was observed. Changes in the perilimbal sclera did not correlate with IOP.

The optical density of the trabecular meshwork in the superior quadrant and of the perilimbal sclera in all quadrants negatively correlated with age. Meanwhile, perilimbal scleral heterogeneity in the temporal and inferior quadrants positively correlated with age, while in the temporal, superior, and inferior quadrants, it negatively correlated with axial length.

CONCLUSION. The optical density and heterogeneity of the perilimbal sclera and trabecular meshwork differ between normal and glaucomatous eyes. Specific parameters vary with glaucoma stage and correlate with IOP. Changes in the optical density and heterogeneity of these structures, as identified by OCT, are consistent with the histopathological findings, suggesting their potential use in clinical practice as predictors of the development and progression of open-angle glaucoma. Further studies on a larger cohort of patients are needed.

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