Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary, Boston, MA, USA.
Hear Res. 2010 May;263(1-2):78-84. doi: 10.1016/j.heares.2009.11.005. Epub 2009 Nov 10.
Stroboscopic holography was used to quantify dynamic deformations of the tympanic membrane (TM) of the entire surface of the TM before and after cartilage tympanoplasty of the posterior or posterior-superior part of the TM. Cartilage is widely used in tympanoplasties to provide mechanical stability for the TM. Three human cadaveric temporal bones were used. A 6 mm x 3 mm oval cartilage graft was placed through the widely opened facial recess onto the medial surface of the posterior or posterior-superior part of the TM. The graft was either in contact with the bony tympanic rim and manubrium or not. Graft thickness was either 0.5 or 1.0mm. Stroboscopic holography produced displacement amplitude and phase maps of the TM surface in response to stimulus sound. Sound stimuli were 0.5, 1, 4 and 7 (or 8)kHz tones. Middle-ear impedance was measured from the motion of the entire TM. Cartilage placement generally produced reductions in the motion of the TM apposed to the cartilage, especially at 4 kHz and 7 or 8 kHz. Some parts of the TM showed altered motion compared to the control in all three cases. In general, middle-ear impedance was either unchanged or increased somewhat after cartilage reconstruction both at low (0.5 and 1 kHz) and high (4 and 7 kHz) frequencies. At 4 kHz, with the 1.0mm thick graft that was in contact with the bony tympanic rim, the impedance slightly decreased. While our earlier work with time-averaged holography allowed us to observe differences in the pattern of TM motion caused by application of cartilage to the TM, stroboscopic holography is more sensitive to TM motions and allowed us to quantify the magnitude and phase of motion of each point on the TM surface. Nonetheless, our results are similar to those of our earlier work: The placement of cartilage on the medial surface of TM reduces the motion of the TM that apposes the cartilage. These obvious local changes occur even though the cartilage had little effect on the sound-induced motion of the stapes.
频闪全息术用于定量测量鼓膜（TM）整个表面在进行 TM 后上部或后上部软骨鼓室成形术前和术后的动态变形。软骨广泛用于鼓室成形术，为 TM 提供机械稳定性。使用了三个人类尸体颞骨。将一个 6mmx3mm 的椭圆形软骨移植物通过广泛开放的面神经隐窝放置在 TM 后上部或后上部的内表面上。移植物要么与骨性鼓膜缘和柄接触，要么不接触。移植物的厚度为 0.5 或 1.0mm。频闪全息术产生了 TM 表面对刺激声音的位移幅度和相位图。声音刺激为 0.5、1、4 和 7（或 8）kHz 音。从中耳的运动测量了中耳阻抗。软骨放置通常会减少与软骨接触的 TM 的运动，尤其是在 4kHz 和 7 或 8kHz 时。在所有三种情况下，与对照相比，TM 的某些部分显示出与对照不同的运动。一般来说，在低频（0.5 和 1kHz）和高频（4 和 7kHz）下，软骨重建后中耳阻抗要么不变，要么略有增加。在 4kHz 时，对于与骨性鼓膜缘接触的 1.0mm 厚移植物，阻抗略有降低。虽然我们之前使用时间平均全息术的工作允许我们观察到将软骨应用于 TM 引起的 TM 运动模式的差异，但频闪全息术对 TM 运动更敏感，并允许我们量化 TM 表面每个点的运动幅度和相位。尽管如此，我们的结果与我们之前的工作相似：在 TM 的内表面放置软骨会减少与软骨接触的 TM 的运动。即使软骨对镫骨的声致运动几乎没有影响，这些明显的局部变化也会发生。
