Ge Ping Jiang, French Lesley C, Ohno Tsunehisa, Zealear David L, Rousseau Bernard
Department of Otolaryngology, Vanderbilt University Bill Wilkerson Center for Otolaryngology and Communication Sciences, Nashville, Tennessee 37232-4480, USA.
Ann Otol Rhinol Laryngol. 2009 Jan;118(1):51-5. doi: 10.1177/000348940911800109.
We describe a method for eliciting phonation in an in vivo rabbit preparation using low-frequency, bipolar pulsed stimulation of the cricothyroid muscles with airflow delivered to the glottis.
Ten New Zealand White breeder rabbits weighing 3 to 5 kg were used in this study. The cricothyroid muscles were isolated bilaterally, and separate pairs of anode-cathode hooked-wire electrodes were inserted into each muscle. A Grass S-88 stimulator and 2 constant-current PSIU6 isolation units were used to deliver bipolar square wave pulses to each cricothyroid muscle, with airflow delivered to the glottis through a cuffed endotracheal tube.
Phonation was evoked with a 50-Hz, 4-mA stimulus train of 1-ms pulses delivered to each cricothyroid muscle. The pulse trains were on for 2 seconds and were repeated every 5 seconds over a period of 180 minutes. Airflow was delivered at 143 cm3/s, producing phonation measuring 71 to 85 dB sound pressure level.
Evoked phonation is feasible in rabbits by use of bipolar stimulation of the cricothyroid muscles with airflow delivered to the glottis. The in vivo rabbit preparation described may provide a useful small animal option for studies of evoked phonation. From the level and consistency of the adduction observed, we hypothesize that current spreading to the underlying adductor muscles and nerves resulted in neural pathway involvement beyond discrete activation of the cricothyroid muscle, providing sufficient approximation of the vocal folds for phonation.
我们描述了一种在活体兔制备中引发发声的方法,即通过对环甲肌进行低频双极脉冲刺激,并向声门输送气流。
本研究使用了10只体重3至5千克的新西兰白兔种兔。双侧分离出环甲肌,将成对的阳极-阴极钩状线电极分别插入每块肌肉。使用Grass S-88刺激器和2个恒流PSIU6隔离单元向每块环甲肌输送双极方波脉冲,气流通过带套囊的气管内导管输送至声门。
向每块环甲肌输送频率为50赫兹、电流为4毫安、脉冲宽度为1毫秒的刺激序列可引发发声。脉冲序列持续2秒,在180分钟内每5秒重复一次。气流以143立方厘米/秒的速度输送,产生的发声声压级为71至85分贝。
通过对环甲肌进行双极刺激并向声门输送气流,在兔中引发发声是可行且一致的。所描述的活体兔制备可为诱发发声的研究提供一种有用的小动物模型。从观察到的内收程度和一致性来看,我们推测电流扩散到下方的内收肌和神经导致神经通路参与,超出了环甲肌的离散激活,为发声提供了足够的声带近似度。