ABSTRACT
@#AIM: To compare the difference of corneal curvature, astigmatism, central corneal thickness and anterior chamber depth between the Pentacam anterior segment analyzer and anterior segment optical coherence tomography(AS-OCT)in young myopic preoperative and senile cataract patients.<p>METHODS: Prospective clinical study.Totally 64 preoperative examinations(124 eyes)and 61 senile cataract patients(85 eyes)were selected. Pentacam and AS-OCT were used to measure the people's parameters of the ophthalmic anterior segment. Paired sample <i>t</i>-test was used to compare the differences of the two devices' measurement results of the two groups. The correlation of the obtained data was analyzed by Pearson correlation analysis. The consistency of the measurement results was analyzed by Bland-Altman plot analysis.<p>RESULTS: There were significant differences in measuring steep Keratometry(Ks), flat Keratometry(Kf)and mean Keratometry(Km)between the two devices of myopia(<i>P</i><0.001), but there was no statistically significant difference in the cataract group(<i>P</i>>0.05). The astigmatic parameters J<sub>0</sub>, central corneal thickness(CCT), and anterior chamber depth(ACD)measured by the devices and there were statistically significant differences between the two devices(<i>P</i><0.05)while there was no significant difference in the measured astigmatic parameters J<sub>45</sub>(<i>P</i>>0.05). The results of Ks, Kf, Km, J<sub>0</sub>, J<sub>45</sub>, CCT and ACD measured by the two devices in both groups were linearly related(<i>P</i><0.001). The Bland-Altman plot analyses showed that the two devices had comparable results for J<sub>0</sub>, J<sub>45</sub>, CCT and ACD. The consistency of Ks, Kf and Km measured by the myopia group was good, while the consistency of Ks, Kf and Km measured by the cataract group was poor.<p>CONCLUSION: Pentacam and AS-OCT measurements of the ophthalmic anterior segment are consistent with astigmatic parameters, CCT and ACD, and can be used interchangeably. The consistency of Ks, Kf and Km is affected by age related factors, and Pentacam is preferred.
ABSTRACT
AIM: To compare corneal curvature and astigmatism values identified with OPD - Scan Ⅲ, lOL Master, Pentacam and KR - 8900 in cataract patients and to evaluate the consistencies and differences. METHODS: In this prospective clinical trial, 45 cataract patients (86 eyes), received treatment at the Department of Ophthalmology in our hospital from April 2017 to June 2017, underwent corneal parameters measurements with four instruments: OPD-Scan Ⅲ, Pentacam, IOL Master, and KR-8900. Measurements included corneal curvature (K1, K2, Km) and astigmatism parameters. The results were assessed using the paired samples t tests, Pearson coefficient,and Biand-Aitman plots. RESULTS: The difference of K1value measured by OPD-ScanⅢ and IOL Master was significant (P<0.001). Significant differences were also found in K2and Km values between OPD - Scan Ⅲ and Pentacam or IOL Master(P<0.05),while others had noncomparable results (P>0 05). All biometry measurements revealed good liner correlation (r=0.408-0.980, P<0.001). The Biand-Aitman showed that the corneal curvature and astigmatism vectors examined by OPD-Scan Ⅲ and Aii other devices had non-comparable results,except for the comparison of K1, K2and Kmmeasured by OPD-Scan Ⅲand KR-8900.CONCLUSION: OPD-Scan Ⅲ and KR-8900 can be interchangeable for the measurements of corneal curvature, while the others are not directly interchangeable. The astigmatic results obtained from OPD-Scan Ⅲ are not completely interchangeable with KR-8900,IOL Master or Pentacam.