Hughes T A, Liu P, Griffiths H, Wiles C M
Department of Medicine (Neurology), University of Wales College of Medicine, UK.
Physiol Meas. 1995 Aug;16(3 Suppl A):A79-86. doi: 10.1088/0967-3334/16/3a/008.
Two electrical impedance tomography (EIT) indices of pharyngeal transit time have been repeatedly measured in 20 normal adults. The time course of change in pharyngeal conductivity whilst swallowing 5, 10 and 20 ml boluses was expressed either as a full width at 20% maximum (FW20) or as a full width at 50% maximum (FW50): the latter could be satisfactorily measured more frequently. Mean coefficients of variation for FW20 and FW50 tended to decrease with increasing bolus volume but this was statistically significant only for FW50 in men. FW20 and FW50 were significantly shorter in men than women and increased with increasing age. FW50 was significantly smaller when larger bolus volumes were swallowed. FW50 was significantly shorter when low-conductivity fluid was used and there was an insignificant trend for it to be longer with electrodes in the highest position. The amplitude of the conductivity change recorded was significantly affected by all factors studied apart from age. If EIT is to be used as a technique for monitoring changes in pharyngeal transit time in patients with neurogenic dysphagia, repeat examinations should be performed under the same conditions and, if possible, large bolus volumes should be used.
已对20名正常成年人反复测量了两个用于评估咽传输时间的电阻抗断层扫描（EIT）指标。吞咽5毫升、10毫升和20毫升团块时咽电导率的变化时间过程，要么表示为最大电导率20%时的全宽（FW20），要么表示为最大电导率50%时的全宽（FW50）：后者能更频繁地得到满意测量。FW20和FW50的平均变异系数倾向于随团块体积增加而降低，但仅男性的FW50在统计学上有显著意义。男性的FW20和FW50显著短于女性，且随年龄增长而增加。吞咽较大团块体积时，FW50显著更小。使用低电导率液体时，FW50显著更短，且电极处于最高位置时FW50有变长的不显著趋势。除年龄外，所研究的所有因素均显著影响记录的电导率变化幅度。如果要将EIT用作监测神经性吞咽困难患者咽传输时间变化的技术，则应在相同条件下进行重复检查，并且如果可能的话，应使用较大的团块体积。
