Ocular pulse amplitude in patients with asymmetric primary open-angle glaucoma

To evaluate ocular pulse amplitude (OPA) using the dynamic contour tonometer (DCT) in patients with asymmetric primary open-angle glaucoma (POAG) and asymmetric intra-ocular pressure (IOP).

The participants consisted of 48 patients (96 eyes) with asymmetric POAG. Three measurements of IOP and OPA were taken using DCT. The diagnosis of asymmetry required a difference of glaucomatous visual field loss greater than 6 dB in the global index MD and a difference of 5 mmHg in IOP measured by Goldmann tonometry between the more affected and the contra-lateral eye. All participants underwent full ophthalmologic clinical assessment including ultrasonic pachymetry and biometric measurements. Exclusion criteria were corneal diseases or scars, topical or systemic glaucomatous medications, and previous ocular surgery.

No difference (p = 0.142) was found between the axial length measurements of the better eyes group (22.95 ± 0.91 mm) and worse eyes group (22.85 ± 0.97 mm). There was a statistically significant difference (p = 0.011) between the central corneal thickness values of the better eyes group (537.08 ± 29.54 μm) and worse eyes group (534.40 ± 29.87 μm). The OPA values of the better eyes group (3.32 ± 1.14 mmHg) were significantly lower (p = 0.001) than those obtained in the worse eyes group (3.83 ± 1.27 mmHg). When correcting the OPA readings by the IOP there was no statistical difference between groups (p = 0.996).

Higher OPA values were found in eyes with higher IOP levels and advanced glaucoma's lesions in asymmetric hypertensive POAG patients. However, after the OPA correction by the IOP levels there was no more statistical difference between eyes.