豚鼠耳蜗灌注的流速安全阈

The safe flow rate of artificial perilymphatic perfusion in guinea pig cochlea

行全耳蜗人工外淋巴灌注，观察不同灌注速度对蜗内电位的影响，并作耳蜗连续切片，观察内耳结构的形态变化。灌注速度分别为：５μｌ／ｍｉｎ，５０μｌ／ｍｉｎ，１００μｌ／ｍｉｎ，２５０μｌ／ｍｉｎ，５００μｌ／ｍｉｎ。当灌注速度为１００μｌ／ｍｉｎ时可使蜗内电位下降，但停灌后电位可恢复。而灌注速度进一步提高为２５０μｌ／ｍｉｎ以上后，蜗内电位即出现不可逆的下降。在灌注速度分别为５μｌ／ｍｉｎ，５０μｌ／ｍｉｎ和１００μｌ／ｍｉｎ时，连续切片观察未发现异常。在２５０μｌ／ｍｉｎ组中有１耳发现有前庭膜塌陷。在５００μｌ／ｍｉｎ组中发现３耳有前庭膜塌陷或破裂。人工外淋巴灌注速度不宜过快，在豚鼠耳所作试验提示，流速以不超过１００μｌ／ｍｉｎ为宜。

Abstract The perilymphatic space of guinea pig cocmea was perfused with a variety of physiologic artificial perilymph which differented in the perfusive flow rate. The endocochlear potential(EP)was recorded to indicate the effects of the parfusive flow rates on the cochlear func-tion. The perfusive flow rates were divided into 5 groups:5μl/min,50μl/min,100μl/min,250μl/min and 500μl/min. In the groups of 5μl/min and 50μl/min,there was no significant ch ange of EP thrOughout the peried of perfu sion.When the perfusive fiow rate was 100μl/ min,a transitory decline of EP was found during the perfusive period. When the perfusive flow rates were 250μl/min and 500μl/min, the EP were decreased markedly and did not re- turn to the normal level after the stop of perfusion.For morphologic study,inthe groups which the perfusive flow rates reached 250μl/min,4 of 10 ears were found that the Reissner’s membrane was collapsed and ruptured. It was suggested that the flow rate of peri- ymphatic perfusion should not exceed 100μl/min. The metheds of artificial perilymphatic perfusion and recording of EP were described in detail.