Mechanisms of Hearing Loss in a Guinea Pig Model of Superior Semicircular Canal Dehiscence

Figure 5

Effects of SSCD with different sizes and locations on the movement of the tympanic membrane, stapes head, and RWM by LDV measurements presurgery and postsurgery SSCD. (a) Vibration of the tympanic membrane (Vu) in the groups with different sizes of dehiscence (0.5 × 0.5 mm and 1.0 × 0.5 mm) near the oval window. Vu in the group with the larger dehiscence (1.0 × 0.5 mm; red line) was stronger than in the group with the smaller dehiscence (0.5 × 0.5 mm; black line), in the range of 500–1000 Hz (). (b) Vibration of the stapes head (Vs) in groups with different sizes of dehiscence (0.5 × 0.5 mm and 1.0 × 0.5 mm) near the oval window. Vs in the group with the larger dehiscence (1.0 × 0.5 mm; red line) was stronger than in the group with the smaller dehiscence (0.5 × 0.5 mm; black line), in the range of 400–1000 Hz (). (c) Vibration of the round window (Vw) in groups with different sizes of dehiscence (0.5 × 0.5 mm and 1.0 × 0.5 mm) near the oval window. Vw in the group with the larger dehiscence (1.0 × 0.5 mm; red line) was weaker than in the group with the smaller dehiscence (0.5 × 0.5 mm; black line), in the range of 400–2000 Hz (). (d) Vibration of the tympanic membrane in the groups with different sizes of dehiscence located at different points ( in each group). Vibration in the group with the larger dehiscence (1.0 × 0.5 mm; red line) was stronger than in the group with the smaller dehiscence (0.5 × 0.5 mm; black line) near the oval window () in the range of 500–1000 Hz. Vibration in the group with the smaller dehiscence (0.5 × 0.5 mm; black line) near the oval window was stronger than in the groups with larger (green line) or small dehiscences (blue line) far from the oval window () in the range of 400–800 Hz. There were no statistically significant differences between the groups with different sized dehiscences away from the oval window ().

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