AIM: To compare the anterior segment measurements obtained by rotating Scheimpflug camera(Pentacam) and Scanning-slit topography(Orbscan IIz) in keratoconic eyes.METHODS: A total of 121 patients, 71 males(58.7%)and 50...AIM: To compare the anterior segment measurements obtained by rotating Scheimpflug camera(Pentacam) and Scanning-slit topography(Orbscan IIz) in keratoconic eyes.METHODS: A total of 121 patients, 71 males(58.7%)and 50 females(41.3%)(214 eyes) with the diagnosis of keratoconus(KC) were enrolled in this study. Following diagnosis of KC by slit-lamp biomicroscopic examination, central corneal thickness(CCT), thinnest corneal thickness(TCT), anterior chamber depth(ACD),and pupil diameter(PD) were measured by a single examiner using successive instrumentation by Pentacam and Orbscan.RESULTS: There was no significant difference between the two instruments for the measurement of CCT and TCT. In contrast, scanning-slit topography measured ACD(3.46±0.40 mm vs 3.38±0.33 mm, P =0.019) and PD(4.97 ±1.26 mm vs 4.08 ±1.19 mm, P 【0.001) significantly larger than rotating Scheimpflug camera.The two devices made similar measurements for CCT(95% CI:-2.94 to5.06, P =0.602). However, the mean difference for TCT was-6.28(95% CI:-10.51 to-2.06, P =0.004) showing a thinner measurement by Orbscan than by Pentacam. In terms of the ACD, the mean difference was 0.08 mm(95%CI: 0.04 to 0.12, P 【0.001) with Orbscan giving a slightly larger value than Pentacam. Similarly, Orbscan measurement for PD was longer than Pentacam(95% CI:0.68 to 1.08, P 【0.001).CONCLUSION: A good agreement was found between Pentacam and Orbscan concerning CCT measurement while comparing scanning-slit topography and rotatingScheimpflug camera there was an underestimation for TCT and overestimation for ACD and PD.展开更多
Background Measurement of anterior segment parameters plays an important role in diagnosis and treatment of glaucoma. The objective of this study was to evaluate the repeatability and reproducibility of anterior chamb...Background Measurement of anterior segment parameters plays an important role in diagnosis and treatment of glaucoma. The objective of this study was to evaluate the repeatability and reproducibility of anterior chamber volume （ACV） measurements with rotating scheimpflug camera （RSC） and to examine agreement with anterior segment optical coherence tomography （AS-OCT）. Methods Thirty nine healthy normal subjects were recruited from the Eye Center of Tongren Hospital. ACV was measured using RSC and AS-OCT in a randomly selected eye for each subject. For RSC measurements, both automatic and manual ACV measurements and 2 independent operators＇ ACV measurements were obtained. All subjects were invited for 3 visits within a week to evaluate repeatability and reproducibility of ACV measurement by RSC. Agreement was evaluated between RSC and AS-OCT. Results Good repeatability and reproducibility were found for both automatic and manual ACV measurements obtained by RSC. For intrasession repeatability, coefficient of variation （CVw） and intraclass correlation coefficient （ICC） values for automatic were 3.52% and 0.98; the values for manual were 3.44% and 0.97, respectively. For intersession reproducibility, the respective CVw and ICC values were 3.96% and 0.96. Good agreement was also found in 2 operators for both automatic and manual ACV measurements; nevertheless, poor agreement was found between RSC and AS-OCT （95% confidence interval （CO for agreement of automatic RSC measurement versus AS-OCT were -96.3 to 72.8 pl and 95% CI for agreement of manual RSC measurement versus AS-OCT were between 41.7 to 10.1 #1 ）. Conclusions Both RSC automatic and manual ACV measurements showed good repeatability and reproducibility, and showed comparable agreement between 2 independent operators, but poor agreement was found between RSC and AS-OCT.展开更多
AIM：To evaluate the effects of posterior corneal surface measurements on the accuracy of total estimated corneal astigmatism.METHODS：Fifty-seven patients with toric intraocular lens（IOL） implantation and posterior...AIM：To evaluate the effects of posterior corneal surface measurements on the accuracy of total estimated corneal astigmatism.METHODS：Fifty-seven patients with toric intraocular lens（IOL） implantation and posterior corneal astigmatism exceeding 0.5 diopter were enrolled in this retrospective study.The keratometric astigmatism（KA） and total corneal astigmatism（TA） were measured using a Pentacam rotating Scheimpflug camera to assess the outcomes of AcrySof IOL implantation.Toric lOLs were evaluated in 26 eyes using KA measurements and in 31 eyes using TA measurements.Preoperative corneal astigmatism and postoperative refractive astigmatism were recorded for statistical analysis.The cylindrical power of toric lOLs was estimated in all eyes.RESULTS：In all cases,the difference of toric IOL astigmatism magnitude between KA and TA measurements for the estimation of preoperative corneal astigmatism was statistically significant.Of a total of 57 cases,the 50.88%decreased from Tn to Tn-1 and 10.53%decreased from Tn to Tn-2.In all cases,5.26%increased from Tn to Tn＋1.The mean postoperative astigmatism within the TA group was significantly lower than that in the KA group.CONCLUSION：The accuracy of total corneal astigmatism calculations and the efficacy of toric IOL correction can be enhanced by measuring both the anterior and posterior corneal surfaces using a Pentacam rotating Scheimpflug camera.展开更多
文摘AIM: To compare the anterior segment measurements obtained by rotating Scheimpflug camera(Pentacam) and Scanning-slit topography(Orbscan IIz) in keratoconic eyes.METHODS: A total of 121 patients, 71 males(58.7%)and 50 females(41.3%)(214 eyes) with the diagnosis of keratoconus(KC) were enrolled in this study. Following diagnosis of KC by slit-lamp biomicroscopic examination, central corneal thickness(CCT), thinnest corneal thickness(TCT), anterior chamber depth(ACD),and pupil diameter(PD) were measured by a single examiner using successive instrumentation by Pentacam and Orbscan.RESULTS: There was no significant difference between the two instruments for the measurement of CCT and TCT. In contrast, scanning-slit topography measured ACD(3.46±0.40 mm vs 3.38±0.33 mm, P =0.019) and PD(4.97 ±1.26 mm vs 4.08 ±1.19 mm, P 【0.001) significantly larger than rotating Scheimpflug camera.The two devices made similar measurements for CCT(95% CI:-2.94 to5.06, P =0.602). However, the mean difference for TCT was-6.28(95% CI:-10.51 to-2.06, P =0.004) showing a thinner measurement by Orbscan than by Pentacam. In terms of the ACD, the mean difference was 0.08 mm(95%CI: 0.04 to 0.12, P 【0.001) with Orbscan giving a slightly larger value than Pentacam. Similarly, Orbscan measurement for PD was longer than Pentacam(95% CI:0.68 to 1.08, P 【0.001).CONCLUSION: A good agreement was found between Pentacam and Orbscan concerning CCT measurement while comparing scanning-slit topography and rotatingScheimpflug camera there was an underestimation for TCT and overestimation for ACD and PD.
文摘Background Measurement of anterior segment parameters plays an important role in diagnosis and treatment of glaucoma. The objective of this study was to evaluate the repeatability and reproducibility of anterior chamber volume （ACV） measurements with rotating scheimpflug camera （RSC） and to examine agreement with anterior segment optical coherence tomography （AS-OCT）. Methods Thirty nine healthy normal subjects were recruited from the Eye Center of Tongren Hospital. ACV was measured using RSC and AS-OCT in a randomly selected eye for each subject. For RSC measurements, both automatic and manual ACV measurements and 2 independent operators＇ ACV measurements were obtained. All subjects were invited for 3 visits within a week to evaluate repeatability and reproducibility of ACV measurement by RSC. Agreement was evaluated between RSC and AS-OCT. Results Good repeatability and reproducibility were found for both automatic and manual ACV measurements obtained by RSC. For intrasession repeatability, coefficient of variation （CVw） and intraclass correlation coefficient （ICC） values for automatic were 3.52% and 0.98; the values for manual were 3.44% and 0.97, respectively. For intersession reproducibility, the respective CVw and ICC values were 3.96% and 0.96. Good agreement was also found in 2 operators for both automatic and manual ACV measurements; nevertheless, poor agreement was found between RSC and AS-OCT （95% confidence interval （CO for agreement of automatic RSC measurement versus AS-OCT were -96.3 to 72.8 pl and 95% CI for agreement of manual RSC measurement versus AS-OCT were between 41.7 to 10.1 #1 ）. Conclusions Both RSC automatic and manual ACV measurements showed good repeatability and reproducibility, and showed comparable agreement between 2 independent operators, but poor agreement was found between RSC and AS-OCT.
文摘AIM：To evaluate the effects of posterior corneal surface measurements on the accuracy of total estimated corneal astigmatism.METHODS：Fifty-seven patients with toric intraocular lens（IOL） implantation and posterior corneal astigmatism exceeding 0.5 diopter were enrolled in this retrospective study.The keratometric astigmatism（KA） and total corneal astigmatism（TA） were measured using a Pentacam rotating Scheimpflug camera to assess the outcomes of AcrySof IOL implantation.Toric lOLs were evaluated in 26 eyes using KA measurements and in 31 eyes using TA measurements.Preoperative corneal astigmatism and postoperative refractive astigmatism were recorded for statistical analysis.The cylindrical power of toric lOLs was estimated in all eyes.RESULTS：In all cases,the difference of toric IOL astigmatism magnitude between KA and TA measurements for the estimation of preoperative corneal astigmatism was statistically significant.Of a total of 57 cases,the 50.88%decreased from Tn to Tn-1 and 10.53%decreased from Tn to Tn-2.In all cases,5.26%increased from Tn to Tn＋1.The mean postoperative astigmatism within the TA group was significantly lower than that in the KA group.CONCLUSION：The accuracy of total corneal astigmatism calculations and the efficacy of toric IOL correction can be enhanced by measuring both the anterior and posterior corneal surfaces using a Pentacam rotating Scheimpflug camera.
