Assessment Of The Possibility Of Using Osirix To Measure The Optical Coherence Tomography Pictures Of Infectious Keratitis

ObjectiveAnalyse the posiibility of using OsiriX to measure the anterior segment optical coherence tomography(AS-OCT) pictures of infectious keratitis,including corneal thickness, infiltration area and the value which related to infiltration density(OCT value).MethodWe retrospectively reviewed the anterior segment optical coherence tomography pictures of who diagnosed as infectious keratitis from December2011to March2012in our hospital.Firstly, we compare the corneal thickness measured by the built-in software of Zeiss Visante OCT device and by OsiriX. Then we assess the possibility of using OsiriX to measure AS-OCT pictures of infiltration area and OCT value. Statistical methods used SPSS(Version16.0) software for data processing. The agreement was evaluated by the method of Paired-Samples T Test, Pearson correlation analysis and Bland—Altman Analysis. The repeatability and reproducibility was evaluated by the method of Paired-Samples T Test and Intraclass Correlation Coefficients(ICC). P<0.05as a statistically significant difference. Result1, The mean corneal thickness measured by Visante OCT was700.19±171.67μm, whereas measured by OsiriX it was694±166.84μm。 The average difference value was6.21±10.45μm, and showed statistically significant difference (P<0.05). Pearson correlation analysis displayed high relation between results of corneal thickness measured by the two methods (r=0.998, P<0.05). And for Bland-Altman analysis, there is only3.1%(1/32) outside the95%limits of agreement.2、The result1and result2of mean corneal thickness caculated by the same operator using OsiriX were respectively2207641.94±1196023.88μm2and2170665.94±1170061.01u m2. There is no significant difference between the two results (P value>0.05), and it showed good repeatability (ICC>0.9). The results of mean corneal thickness calculated by operator1and operator2were respectively2207641.94±1196023.88μm2and2201682.04±1177914.01μm2, they also showed no significant difference (P value>0.05) and good reproducibility (ICC>0.9).3、The result1and result2of OCT value caculated by the same operator using OsiriX were respectively368.38±135.22and376.72±133.54. There is no significant difference between the two results (P value>0.05), and it showed good repeatability (ICC>0.9). The results of OCT value calculated by operator1and operator2were respectively368.38±135.22and371.63±130.06, they also showed no significant difference (P value>0.05) and good reproducibility (ICC>0.9). Conclusion:The two methods got agreement in measuring corneal thickness.At the same time, OsiriX showed good repeatability and reproducibility when calculating the infiltration area and OCT value of the ASS-OCT pictures of infectious keratitis.