Tamai K, Toumoto E, Yamada K, Ogura Y
Department of Ophthalmology, Nagoya City University Medical School, Nagoya, Japan.
Curr Eye Res. 1999 Apr;18(4):249-53. doi: 10.1076/ceyr.18.4.249.5361.
To investigate the effects of irrigation temperature on choroidal circulation during vitrectomy.
After anesthetized albino rabbits underwent closed vitrectomy, choroidal blood flow was monitored while the vitreous cavity was irrigated with solutions (BSS plus) of various temperatures (6-42 degrees C). Irrigation pressure was maintained at 15 mmHg. A non-contact Doppler laser flowmeter was used to measure choroidal blood flow. Temperature change at the retina and mid-vitreous was also measured during irrigation.
Choroidal blood flow showed a downward peak when perfused at 34 degrees C. As irrigation temperatures deviated above or below 34 degrees C, the blood flow increased. However, when irrigation temperature was below 16 degrees C, the blood flow decreased as the temperature declined. The temperature at the retina was maintained at a relatively constant level when irrigation was between 30 degrees C and 40 degrees C.
The choroid acts as a thermostat to minimize intraocular temperature fluctuations by changing its blood flow.
研究玻璃体切割术中冲洗液温度对脉络膜循环的影响。
对白化兔进行麻醉后实施闭合式玻璃体切割术，在用不同温度（6 - 42摄氏度）的溶液（平衡盐溶液加）冲洗玻璃体腔时，监测脉络膜血流。冲洗压力维持在15 mmHg。使用非接触式多普勒激光血流仪测量脉络膜血流。冲洗过程中还测量了视网膜和玻璃体中部的温度变化。
当用34摄氏度的溶液灌注时，脉络膜血流出现向下的峰值。随着冲洗温度偏离34摄氏度上下，血流增加。然而，当冲洗温度低于16摄氏度时，血流随温度下降而减少。当冲洗温度在30摄氏度至40摄氏度之间时，视网膜温度保持在相对恒定的水平。
脉络膜起到恒温器的作用，通过改变其血流来最小化眼内温度波动。
