Valsalva Maneuver-induced Changes in Anterior Lamina Cribrosa Surface Depth: A Comparison between Normal and Glaucomatous Eyes

PURPOSE:To investigate the influence of the Valsalva maneuver (VM) on anterior lamina cribrosa surface depth (ALCSD), and to compare normal with treated glaucomatous eyes in terms of this effect. METHODS:Thirty-two patients (32 eyes) with early-to-moderate glaucoma under treatment and 30 normal healthy participants (30 eyes) were prospectively enrolled. Study subjects performed the VM by blowing through a mouthpiece attached to a handheld manometer; expiratory pressure during the maneuver ranged from 35 to 40 mmHg. Swept-source optical coherence tomography (SS-OCT) B-scans were performed during phase 2 of the VM (from 10 to 15 s). RESULTS:The ALCSD was significantly different in the normal eyes only, decreasing by 31.90±14.81 μm (−8.79%; 394.85±53.63 μm at baseline vs. 362.95±44.23 μm during the VM; P