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Purpose: To assess the axial length (AL) measurement failure rate using partial?coherence interferometry (PCI) and swept?source optical coherence tomography (SS?OCT) in dense cataracts. As a secondary outcome, the SS?OCT biometry was compared to immersion ultrasound. Methods: This is a prospective cross?sectional and comparative study. Seventy eyes from 70 patients with dense cataracts were enrolled in this study. Dense cataract was defined according to the Lens Opacities Classification System III (LOCS III) scores equal to or more than NO4, NC4, C4, and P3. The failure rate of AL measurement was evaluated using PCI and SS?OCT. Anterior chamber depth (ACD), lens thickness (LT), and AL measurements obtained by SS?OCT were compared with IUS. Results: AL measurement failure rate with PCI was 68.57% and 21.43% with SS?OCT (P = 0.007). AL measurement was achieved in 69.23% of NO4, 66.6% of P3, and 15.3% of mixed cataracts using PCI, while SS?OCT was achieved in 100% of NO4, NO5, P3, and P5 and 76.9% of mixed cataracts. Cortical cataracts alone did not influence AL measurement. Biometric data of ACD, LT, and AL were statistically different comparing US and SS?OCT with a good correlation of AL. Conclusion: SS?OCT significantly improves the rate of successful AL measurements when compared to PCI in dense cataracts. The LOCS III clinical cut?off for the use of SS?OCT ocular biometry may well be up to P4 and NO5
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Objective To explore the application value of INTERGROWTH-21st standard evaluate intrauterine growth restriction (IUGR).We aimed at predicting IUGR with ultrasonic fetal growth measurements.Methods A prospective cohort of singleton pregnancy scanned after 28 gestational weeks was constructed.The Z-score values of growth measurements were calculated using the INTERGROWTH-21st standard.Logistic regression equation was used to establish the prediction formula.Finally,the new formula was compared with the traditional Hadlock method to predict the accuracy of IUGR.We assessed outcomes for consenting participants who attended research scans and delivered at the Obstetrics and Gynecology Hospital of Fudan University.Results A total of 834 patients fulfilling the inclusion criteria were included.After the exclusion of 143 lost cases,565 of control cases and 126 of IUGR cases were obtained.The sensitivity,specificity,positive predictivevalue,negative predictive value,false positive rate and false negative rate of prediction model wererespectively:88.9 ％,85.4 ％,57.7 ％,97.2 ％,14.6 ％,11.1 ％.In contrast,the values of Hadlock wererespectively:81.7％,82.7％,51.2％,95.3％,17.3％,18.3％.Conclusions This study shows aprediction model of IUGR.INTERGROWTH-21st standard improved the diagnostic accuracy of IUGR,especially enhanced the positive predictive value.
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Abstract?AIM: To evaluate the clinical application of IOL Master by comparing with traditional ultrasound biometry on the accuracy and characteristics of intraocular lens calculation.?METHODS:Data was analyzed from 164 patients ( 206 eyes ) with age - related cataracts who underwent phacoemulsification and intraocular lens ( IOL ) implantation in our hospital from June 2014 to June 2015. Before surgery, axial length and corneal curvature were measured with IOL Master and combined application of ultrasonic or manual keratometry, respectively. Phacoemulsification and foldable lens implantation were done in the patients. IOL power calculation was carried out using the SRK-Ⅱformula with the basis of IOL Master data. The visual acuity and refractive outcome were followed-up for 3mo postoperatively.?RESULTS:There was a significant difference between the two methods on axial length measurement which was 23. 86 ± 1. 05mm by IOL Master and 23. 50 ± 0. 83mm by ultrasound ( P = 0. 025 ). There was also a significant difference between the two methods on corneal curvature measurement which was 44. 18 ± 1. 35D by IOL Master and 43. 70 ± 1. 41D by keratometry ( P = 0. 01 ). The mean absolute error(MAE), at 3mo after operation, was 0. 41± 0. 30D and 0. 93 ± 1. 10D by the IOL Master and ultrasound groups, respectively, there was a significant difference between the two methods(P=0. 027).?CONCLUSION:The IOL Master is a non-contact, safe,easy-to-do and patient-friendly methods for axial length and corneal curvature measurement with high accuracy, thus it can calculate the IOL power more accurate and improve the predictive value for postoperative refraction.
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Background The accuracy of biometric measurement is critical for precise diagnoses and prognosis evaluation of ocular diseases.Objective The present study was to evaluate the differences of Lenstar with A-scan ultrasound biometry or keratometer in ocular bio-measurement.Methods Written informed consent was obtained from each subject before examination.Total 43 eyes of 40 age-related cataract patients were enrolled in this study.Axial length,corneal curvature (K1,K2,Km) and intraocular lens (IOL) power were measured with Lenstar,A-scan ultrasound biometry and keratometer,separately.The differences of measuring outcomes were compared between these two methods according to a paired samples t test,and the agreement analysis of measuring outcomes between Lenstar and A-scan ultrasound biometry or keratometer was performed by Blant-Altman plots.Results Thirty-five eyes finished the clinical bio-measurement.The axial length was (23.341 ± 1.208) mm and (23.268 ±1.157)mm based on Lenstar method and A-scan ultrasound biometry method,respectively,with a insignificant difference between them(t =0.260,P=0.796).No significant differences were found in the K1,K2 and Km values between Lenstar and keratometer methods (t =0.526,P =0.601 ; t =0.927,P =0.357 ; t =0.213,P =0.832).The IOL power was (20.371 ±2.827) D and (20.729 ± 2.672) D,respectively in Lenstar method and keratometer method,without statistically significant difference between them (t =0.543,P =0.589).Bland-Altamn agreement analysis showed that the dots of 11％ (4/35),0％ (0/100),9％(3/35),9％ (3/35),6％ (2/35) were out of 95％ confidence limit,and the absolute values of maximal difference value between Lenstar and A-scan ultrasound biometry or keratometer methods was 0.39 mm,1.31 D,1.30 D,0.77 D and 1.00 D in ocular axial length,K1,K2 and Km values and IOL power,respectively.Conclusions As a new bio-measuring method,Lenstar can offer multiple biometric parameters by single procedure.However,an inconsistent measuring outcome is seen between Lenstar and Ascan ultrasound biometry or keratometer.So whether Lenstar can replace A-scan ultrasound biometry or keratometer still need further large simple clinical trail.