Diagnostics
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2021
·Vol. 11
·期 8
·1466
·
IF 3.706
Piotr Kanclerz,Ramin Khoramnia,Xiaogang Wang
Introduction: Accurate assessment of the corneal shape is important in cataract and refractive surgery, both in screening of candidates as well as for analyzing postoperative outcomes. Although corneal topography and tomography are widely used, it is common that these technologies are confused. The aim of this study was to present the current developments of these technologies and particularly distinguish between corneal topography and tomography. Methods: The PubMed, Web of Science and Embase databases were the main resources used to investigate the medical literature. The following
研究领域:
眼科学
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屈光外科学
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影像学
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生物医学工程
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临床诊断学
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DOI
高影响因子
Photodiagnosis and Photodynamic Therapy
·
2024
·
IF 3.1
Jian-Feng Zhao,Chen Yang,Jie Zhou,Hai-Yan Zhang,Yu Geng
Purpose To assess the variability and correlation of ocular biometric parameters in eyes with cataracts and examine their association with age and gender. Methods A retrospective analysis was performed on biometric data from 7,458 eyes without retinal pathologies, using an optical biometer equipped with low-coherence reflectometry technology. Pearson's correlation coefficients (r) were used to evaluate the relationships between age, gender, and various ocular parameters, including axial length (AL), anterior chamber depth (ACD), lens thickness (LT), central corneal thickness (CCT), corneal refractive power (Km), and white-to-white (WTW) measurement. Results The mean AL was 23.82 ± 1.83 mm (SD). Among the study cohort, 8.0 % (593 eyes) were categorized as having short AL (AL ≤ 22 mm), 60.5 % (4,520 eyes) as having normal AL (22 mm < AL ≤ 24 mm), 21.2 % (1,579 eyes) as having long AL (24 mm < AL ≤ 26 mm), and 10.3 % (766 eyes) as having a AL (> 26 mm). The mean age of the cohort was 64.18 ± 14.95 years (range: 18 - 98 years), with males averaging 56.53 ± 13.88 years and females averaging 72.19 ± 11.41 years. Mean values for ACD, LT, Km, CCT, WTW, and angle kappa were found to vary with both age and gender. Males demonstrated significantly longer AL, deeper ACD, thicker LT, larger WTW, and lower Km compared to females ( P < 0.05). Although males exhibited a greater anterior segment length (ASL), this difference did not reach statistical significance ( P > 0.05). No significant correlation was found between ACD and AL in the short and long AL groups, while a positive correlation was observed in the normal and long AL groups. Additionally, LT demonstrated a negative correlation with AL in the normal AL group but a positive correlation in the long AL group. Conclusions Cataracts develop at a greater age in female patients than in males. Ocular biometric parameters, including ACD, LT, CCT, Km, and (WTW) measurement, are influenced by age and gender. Lens thickness is the primary factor affecting ACD, though CCT, Km, and WTW also play significant roles. Furthermore, a negative correlation between AL and LT was identified, with variations depending on AL classification.
研究领域:
眼科
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生物医学工程
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临床研究
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老年医学
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屈光手术
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DOI
高影响因子
Eye and Vision
·
2021
·Vol. 8
·期 1
·22
·
IF 3.257
Meng Jiaqi,Wei Ling,He Wenwen,Qi Jiao,Lu Yi,Zhu Xiangjia
Background To evaluate the distribution of lens thickness (LT) and its associations with other ocular biometric factors among cataract patients in Shanghai. Methods Twenty-four thousand thirteen eyes from 24,013 cataract patients were retrospectively included. Ocular biometric factors including LT, central corneal thickness (CCT), anterior chamber depth (ACD), white-to-white (WTW) distance, anterior corneal curvature, and axial length (AL) were obtained using the IOLMaster700. The associations between LT and general or ocular factors were assessed. Results The mean age was 62.5 ± 13.6 years and 56.1% were female. The mean LT was 4.51 ± 0.46 mm. The LT was greater in older patients ( P < 0.001). LT was positively correlated with CCT, while negatively correlated with ACD, WTW, and anterior corneal curvature ( P < 0.001). Multivariate analysis revealed that increased LT was associated with older age, male gender, thicker CCT, shallower ACD, larger WTW, and flatter anterior corneal curvature ( P < 0.001). LT changed with a variable behavior according to AL. In short eyes LT increased as AL increased, then decreased with longer AL in normal eyes and moderate myopic eyes, but increased again as AL increased in highly myopic eyes. Thickest LT was found in the 20.01–22 mm AL group. The correlation between LT and other biometric factors remained significant when stratified by ALs. Conclusions In a large Chinese cataractous population, we found that the thicker lens may be associated with older age, male gender, thicker CCT, shallower ACD, larger WTW, and flatter anterior corneal curvature. As AL increased, the change of LT was nonlinear, with the thickest lens seen in the 20–22 mm AL group.
研究领域:
眼科
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生物医学工程
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临床眼科学
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屈光手术
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白内障研究
✓ 已验证
DOI
高影响因子
Eye and Vision
·
2021
·Vol. 8
·期 1
·9
·
IF 3.257
Wang Junjie,Lopes Bernardo T.,Li Hechen,Vinciguerra Riccardo,Cao Si,Wu Songan,Zhu Rong,Wang Qinmei,Zheng Xiaobo,Bao Fangjun,Elsheikh Ahmed
Background Corneal refractive surgery has become reliable for correcting refractive errors, but it can induce unintended ocular changes that alter refractive outcomes. This study is to evaluate the unintended changes in ocular biometric parameters over a 6-month follow-up period after femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE). Methods 156 consecutive myopic patients scheduled for FS-LASIK and SMILE were included in this study. Central corneal thickness (CCT), mean curvature of the corneal posterior surface (K pm ), internal anterior chamber depth (IACD) and the length from corneal endothelium to retina (ER) were evaluated before and after surgery over a 6-month period. Results Both the FS-LASIK and SMILE groups (closely matched at the pre-surgery stage) experienced flatter K pm , shallower IACD and decreased ER 1 week post-surgery ( P < 0.01), and these changes were larger in FS-LASIK than in SMILE group. During the 1 week to 6 months follow up period, K pm , IACD and ER remained stable unlike CCT which increased significantly ( P < 0.05), more in the FS-LASIK group. Conclusions During the follow up, the posterior corneal surface became flatter and shifted posteriorly, the anterior chamber depth and the length from the corneal endothelium to retina decreased significantly compared with the pre-surgery stage. These unintended changes in ocular biometric parameters were greater in patients undergoing FS-LASIK than SMILE. The changes present clear challenges for IOL power calculations and should be considered to avoid affecting the outcome of cataract surgery.
研究领域:
眼科学
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屈光手术
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生物测量
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临床研究
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DOI
高影响因子
Scientific Reports
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2021
·Vol. 11
·期 1
·983
·
IF 4.38
Schiano-Lomoriello Domenico,Hoffer Kenneth J.,Abicca Irene,Savini Giacomo
We assess repeatability of automatic measurements of a new anterior segment optical coherence tomographer and biometer (ANTERION) and their agreement with those provided by an anterior segment-optical coherence tomography device combined with Placido-disk corneal topography (MS-39) and a validated optical biometer (IOLMaster 500). A consecutive series of patients underwent three measurements with ANTERION and one with MS-39. A subgroup of patients underwent biometry also with IOLMaster 500. Repeatability was assessed by means of within-subject standard deviation, coefficient of variation (COV), and intraclass correlation coefficient (ICC). Agreement was investigated with the 95% limits of agreement. Paired t-test and Wilcoxon matched-pairs test were performed to compare the measurements of the different devices. Repeatability of ANTERION measurements was high, with ICC > 0.98 for all parameters except astigmatism (0.963); all parameters apart from those related to astigmatism revealed a COV < 1%. Repeatability of astigmatism improved when only eyes whose keratometric astigmatism was higher than 1.0 D were investigated. Most measurements by ANTERION and MS-39 showed good agreement. No significant differences were found between measurements by ANTERION and IOLMaster, but for corneal diameter. ANTERION revealed high repeatability of automatic measurements and good agreement with both MS-39 and IOLMaster for most parameters.
研究领域:
眼科学
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生物医学成像
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临床测量
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屈光手术
✓ 已验证
DOI
高影响因子
Annals of Translational Medicine
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2020
·Vol. 8
·期 22
·1553
·
IF 3.297
Giacomo Savini,Leonardo Taroni,Kenneth J Hoffer
For many decades only a few formulas have been available to calculate the intraocular lens (IOL) power for patients undergoing cataract surgery: the Haigis, Hoffer Q, Holladay 1 and 2 and SRK/T. In recent years, several new formulas for IOL power calculation have been introduced with the aim of improving the accuracy of refraction prediction in eyes undergoing cataract surgery. These include the Barrett Universal II, the Emmetropia Verifying Optical (EVO), the Kane, the Næser 2, the Olsen, the Panacea, the Pearl DGS, the Radial Basis Function (RBF), the T2 and the VRF formulas. Although most of them are unpublished so that their structure is unknown, we give an overview of each formula and report the results of the studies that have compared them. Their performance in short and long eyes is provided and a special focus is given on the issue of segmented axial length, which is a promising method to obtain more accurate outcomes in short and long eyes. Here, the group refractive index originally developed for the IOLMaster may not represent the best method to convert the optical path length into a physical distance. The issue of posterior and total corneal astigmatism (TCA) is discussed in relation to toric IOLs; the latest formulas for toric IOLs and their results are also reported.
研究领域:
眼科学
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白内障手术
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屈光手术
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生物测量
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光学设计
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临床预测模型
✓ 已验证
DOI
PubMed
高影响因子
PLoS One
·
2018
·Vol. 13
·期 2
·e0193023
·
IF 2.766
Yanjun Hua,Wei Qiu,Qiuyi Xiao,Qiang Wu
Purpose
To assess the precision (repeatability and reproducibility) of ocular parameters measured by the Tomey OA-2000 biometer, and to compare them with those measured by the IOLMaster.
Methods
In this prospective study, the right eyes of 108 healthy subjects were included. Three consecutive scans were obtained by 2 observers using the Tomey OA-2000, and in the same session one observer used the IOLMaster (version 5.4.4.0006) for the measurements. About 1 week later, 3 scans were obtained by one observer using the Tomey OA-2000. The axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), keratometer readings, pupil diameter (PD) and corneal diameter (CD) values measured by the Tomey OA-2000 and IOLMaster were analyzed. The coefficient of variation (CoV), intraclass correlation coefficient (ICC), within subject standard deviation (Sw) and 2.77Sw were calculated to assess the repeatability and reproducibility. The paired t test and Bland-Altman plots were used to analyze the differences and agreements of parameters measured by the two devices, respectively.
Results
Intraobserver repeatability, and interobserver and intersession reproducibility of the AL, CCT, ACD, LT, Kf, Ks, Km, PD and CD values measured by the Tomey OA-2000 biometer showed a CoV of less than 1% except that for PD, and an ICC of more than 0.97 except that for PD and CD. The AL, Kf, Ks, Km and CD values measured by the Tomey OA-2000 were 0.058 ± 0.094 mm, 0.088± 0.150 diopters (D), 0.163 ± 0.170 D, 0.127 ± 0.117 D and 0.171 ± 0.217 mm lower than those measured by the IOLMaster, respectively (all Ps < 0.05). However, the ACD values from the two devices were comparable (P = 0.169). The 95% linite of agreement (LoA) of the AL, ACD, CD and all keratometer readings were no more than 0.24 mm, 0.14 mm 0.60 mm and 0.5 D, respectively.
Conclusion
Except for the PD and CD, the ocular parameters measured by the Tomey OA-2000 were highly repeatable and reproducible. Except for the CD value, there was good agreement of ocular parameters measured by the Tomey OA-2000 and the IOLMaster in healthy eyes.
研究领域:
眼科学
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生物医学测量
·
屈光手术
·
白内障手术
·
光学生物测量
✓ 已验证
DOI
高影响因子