非接触眼压计测量高眼压兔模型的准确性

目的:探讨非接触眼压计(NCT)测量高眼压兔模型的准确性。方法:兔全身麻醉后前房、玻璃体腔穿刺,通过平衡盐水柱高低调控眼内压,前房插管显示实际眼压于15.00±0.50,20.00±0.50,25.00±0.50,30.00±0.05,35.00±0.50,40.00±0.50,45.00±0.50mmHg,同时测量相对应的NCT眼压。分析实际眼压与NCT眼压的差异及相关性,以实际眼压作为应变量进行回归分析。结果:兔NCT眼压均低于实际眼压值,有显著性差异(P<0.01)。兔NCT眼压与实际眼压两者具有显著相关性(相关系数r=0.985,P<0.01)。筛选回归方程Y=10.875+1.170X(方差分析F=2691.389,P<0.01),式中Y为实际眼压,X为NCT眼压。结论:NCT能够用于测量高眼压兔模型,实际眼压与NCT眼压之间有直线关系,可借助回归方程通过NCT眼压推断实际眼压,为兔青光眼模型眼压测量提供了实验支持。

Accuracy of intraocular pressure measured by noncontact tonometer in rabbit eyes in high intraocular pressure state

·AIM:To investigate the accuracy of intraocular pressure(IOP)by noncontact tonometer(NCT),and the correlation between the actual IOP and the NCT value in New Zealand white rabbit eyes in high IOP state.·METHODS:The actual IOP was regulated by the height of the saline column through a 22G intravenous catheter needle punctured into vitreous cavity in rabbit eyes,under general anesthesia.The actual IOP was measured with liquid pressure transducer through a 24G needle inserted into the anterior chamber.The NCT value were taken by NCT.The height of the saline column was adjusted,the actual IOP readings in the pressure transducer was varied from 15 to 45mmHg in steps of 5mmHg.At each pressure level the IOP was measured simultaneously with NCT.The NCT error(actual IOP minus NCT value)was calculated.Readings of the two techniques were compared with t-test.The relationship between the actual IOP and NCT value was analyzed with Pearson correlation,and liner regression analysis was performed in the two variables.·RESULTS:NCT values were all obviously lower than actual ones,and the mean NCT error was 13.65±2.25mmHg.The readings of two measurements were of statistically significant differences(P<0.01).But there was also a significant correlation between two measu-rements(r=0.985,P<0.01),and there was a regression equation for actual IOP,Y=10.875+1.170X(F=2691.389,P<0.01),each 0.855mmHg increase in actual IOP(Y)caused 1mmHg increase in NCT values(X).·CONCLUSION:NCT value underestimate the actual IOP in rabbit eyes,NCT error increases as actual IOP increases.There is a significant correlation between two measurements.It is also necessary that the regression equation be used to calibrate NCT value to get a more accurate one.Measuring IOP with NCT is feasible in rabbit eyes in high IOP state.·