Figure 3

Changes in electrophysiological, vestibular, and audiological functions following SC plugging between the success and failure groups. (a) Summating potential/action potential ratios before and after surgery for all patients. Preoperative and postoperative gain values for the same patient are connected by a line. At 3 months after surgery, the mean summating potential/action potential ratio for operated ears had increased significantly in the success group (P < 0.001, paired t-test) but not in the failure group. ***P < 0.001. (b) Cervical vestibular evoked myogenic potential (cVEMP) threshold before and after surgery for all patients. At 3 months after surgery, the mean cVEMP threshold (dB nHL) in operated ears increased in the success group (P < 0.001, paired t-test) but not in the failure group. (c) Natural course of the mean vestibulo-ocular reflex (VOR) gain in the SC over 1 year (before and after surgical plugging). ***P < 0.001. In the success group, the mean VOR gain for plugged SCs decreased immediately (within 1 week after surgery) but improved over time to reach the preoperative value. By contrast, a fluctuating pattern for the VOR gain in the plugged SC over time was observed in the failure group. Data are presented as means ± standard errors of the mean. (d) Preoperative and postoperative bone conduction and air conduction thresholds are shown for all tested frequencies. In the success group, air-bone gaps (ABGs) were significantly reduced after SC plugging, particularly at low frequencies (250 and 500 Hz), due to elevated bone conduction thresholds and reduced air conduction thresholds at low frequencies (250 and 500 Hz), indicating significant improvements (P < 0.001, paired t-test). By contrast, the ABGs remained unchanged in the failure group.