Anderson S
Cromwell Hospital, London.
Br J Audiol. 1995 Apr;29(2):117-28. doi: 10.3109/03005369509086589.
Selective stimulation of the semicircular canal system of one ear by establishing a temperature gradient is still widely used in the clinic in the caloric test. The results obtained are noted for their imprecision and variability. This is, in part, due to a lack of uniformly applied standardized test protocols, as well as difficulties in applying a precise stimulus. The relative merit of the three types of irrigation are reviewed. Whilst some authors argue that both the closed-loop and air irrigators produce even more variability of response than open water systems, the present author believes that intratest replication studies indicate that the closed-loop irrigation stimulus is the least variable and best tolerated by the patient. In perhaps one-fifth of patients, response to the first irrigation is much stronger than subsequent stimulus applications. It is suggested that there may therefore be a case for routinely performing five irrigations in the bithermal caloric test, including a replication of the first irrigation. It is assumed that psychological factors, especially anxiety, may explain the phenomenon of enhanced initial response, and some of the variability of caloric test responses in general. Use of the closed-loop irrigator is advocated for ease of use, reduced routine maintenance and to minimize patient distress, thereby reducing anxiety and result variability.
通过建立温度梯度来选择性刺激一侧耳朵的半规管系统，在临床的冷热试验中仍被广泛应用。所得到的结果以其不精确性和可变性而著称。这在一定程度上是由于缺乏统一应用的标准化测试方案，以及施加精确刺激存在困难。本文回顾了三种冲洗方式的相对优点。虽然一些作者认为，与开放式水系统相比，闭环冲洗器和空气冲洗器产生的反应变异性更大，但作者认为，测试内重复研究表明，闭环冲洗刺激的变异性最小，且患者耐受性最佳。大约五分之一的患者对首次冲洗的反应比后续刺激应用强烈得多。因此，有人建议在双侧冷热试验中常规进行五次冲洗，包括重复首次冲洗。据推测，心理因素，尤其是焦虑，可能解释了初始反应增强的现象，以及一般冷热试验反应的一些变异性。提倡使用闭环冲洗器，因其使用方便、日常维护减少，且能将患者痛苦降至最低，从而减少焦虑和结果变异性。
