scholarly journals Corneal Power, Anterior Segment Length and Lens Power in 14-year-old Chinese Children: the Anyang Childhood Eye Study

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Shi-Ming Li ◽  
Rafael Iribarren ◽  
Meng-Tian Kang ◽  
He Li ◽  
Si-Yuan Li ◽  
...  
Keyword(s):  
Axial Length ◽  
Anterior Segment ◽  
Segment Length ◽  
Full Data ◽  
Mean Values ◽  
Corneal Power ◽  
Ocular Biometry ◽  
Lens Power ◽  
Post Hoc ◽  
Ocular Components

Abstract To analyze the components of young Chinese eyes with special attention to differences in corneal power, anterior segment length and lens power. Cycloplegic refractions and ocular biometry with LENSTAR were used to calculate lens power with Bennett’s method. Mean refraction and mean values for the ocular components of five different refractive groups were studied with ANOVA and post-hoc Scheffé tests. There were 1889 subjects included with full data of refraction and ocular components. As expected, mean axial length was significantly longer in myopic eyes compared to emmetropes. Girls had steeper corneas, more powerful lenses and shorter eyes than boys. Lens power was lower in boys and also lower in myopic eyes. Lens thickness was the same for both genders but was lower in myopic eyes. Although cornea was steeper in myopic eyes in the whole sample, this was a gender effect (more girls in the myopic group) as this difference disappeared when the analysis was split by gender. Anterior segment length was longer in myopic eyes. In conclusion, myopic eyes have lower lens power and longer anterior segment length, that partially compensate their longer axial length. When analyzed by gender, the corneal power is not greater in low and moderate myopic eyes.

scholarly journals Erratum: Corrigendum: Corneal Power, Anterior Segment Length and Lens Power in 14-year-old Chinese Children: the Anyang Childhood Eye Study

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Shi-Ming Li ◽  
Rafael Iribarren ◽  
Meng-Tian Kang ◽  
He Li ◽  
Si-Yuan Li ◽  
...  
Keyword(s):  
Anterior Segment ◽  
Chinese Children ◽  
Segment Length ◽  
Corneal Power ◽  
Old Chinese ◽  
Lens Power

scholarly journals Inter-ocular and inter-visit differences in ocular biometry and refractive outcomes after cataract surgery

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hyun Sup Choi ◽  
Hyo Soon Yoo ◽  
Yerim An ◽  
Sam Young Yoon ◽  
Sung Pyo Park ◽  
...  
Keyword(s):  
Cataract Surgery ◽  
Intraocular Lens ◽  
Axial Length ◽  
The Other ◽  
Corneal Power ◽  
Refractive Outcomes ◽  
Ocular Biometry ◽  
Intraocular Lens Power ◽  
Lens Power ◽  
Group D

Abstract This study aimed to determine whether inter-ocular differences in axial length (AL), corneal power (K), and adjusted emmetropic intraocular lens power (EIOLP) and inter-visit differences in these ocular biometric values, measured on different days, are related to refractive outcomes after cataract surgery. We retrospectively reviewed 279 patients who underwent phacoemulsification. Patients underwent ocular biometry twice (1–4 weeks before and on the day of surgery). Patients were divided into three groups: group S (similar inter-ocular biometry in different measurements; n = 201), group P (inter-ocular differences persisted in the second measurement; n = 37), and group D (inter-ocular difference diminished in the second measurement; n = 41). Postoperative refractive outcomes (mean absolute errors [MAEs]) were compared among the groups. Postoperative MAE2, based on second measurement with reduced inter-ocular biometry difference, was smaller than that calculated using the first measurement (MAE1) with borderline significance in group D (MAE1, 0.49 ± 0.45 diopters vs. MAE2, 0.41 ± 0.33 diopters, p = 0.062). Postoperative MAE2 was greater in group P compared to the other two groups (p = 0.034). Large inter-ocular biometry differences were associated with poor refractive outcomes after cataract surgery. These results indicate that measurements with smaller inter-ocular differences were associated with better refractive outcomes in cases with inter-visit biometry differences.

scholarly journals Comparison of four formulas for the intraocular lens power prediction

2019 ◽  
Author(s):  
Yanjun Hua ◽  
Wei Qiu ◽  
Qiang Wu
Keyword(s):  
Prospective Study ◽  
Intraocular Lens ◽  
Axial Length ◽  
Power Prediction ◽  
Ocular Biometry ◽  
Intraocular Lens Power ◽  
Iol Power ◽  
Lens Power ◽  
Better Than

Abstract Purpose To assess the accuracy of four formulas for intraocular lens (IOL) power prediction in cataractous eyes. METHODS In this prospective study, 51 eyes of 38 cataractous patients with an axial length (AL) between 24.0 and 26.0 mm were included. Preoperatively, Topolyzer, IOLMaster and A-scan were performed. At least 3 months after the surgery, subjective refraction was conducted. Haigis, SRK/T, Hoffer Q and Holladay 1 formulas based on ocular biometry from A-scan combining Topolyzer, IOLMaster combining Topolyzer and IOLMaster only were applied for IOL power prediction. RESULTS The four formulas based on biometry from IOLMaster combining Topolyzer and IOLMaster only performed better than those based on biometry from A-scan combining Topolyzer. Based on biometry from IOLMaster combining Topolyzer, Haigis formula had a mean NEs of -0.03 ± 0.71 D and a mean AEs of 0.53 ± 0.47 D, SRK/T formula had a mean NEs of 0.37 ± 0.72 D and a mean AEs of 0.63 ± 0.50 D, Hoffer Q formula had a mean NEs of 0.05 ± 0.62 D and a mean AEs of 0.43 ± 0.44 D, Holladay 1 formula had a mean NEs of 0.32 ± 0.63 D and a mean AEs of 0.54 ± 0.45 D. Based on biometry from IOLMaster only, Haigis formula had a mean NEs of 0.02 ± 0.54 D and a mean AEs of 0.41 ± 0.36 D, SRK/T formula had a mean NEs of 0.41 ± 0.54 D and a mean AEs of 0.52 ± 0.43 D, Hoffer Q formula had a mean NEs of 0.05 ± 0.58 D and a mean AEs of 0.36 ± 0.46 D, Holladay 1 formula had a mean NEs of 0.32 ± 0.45 D and a mean AEs of 0.43 ± 0.35 D. CONCLUSIONS Haigis and Hoffer Q formulas performed slightly better than SRK/T and Holladay 1 formulas. Therefore, for cataractous patients with moderate AL, all four formulas based the biometry from IOLMaster combining Topolyzer and IOLMaster only can be used for the prediction of IOL power, and the Haigis and Hoffer Q formulas are particularly recommended.

scholarly journals Comparison of Biometric Values and Intraocular Lens Power Calculations Obtained by Ultrasound and Optical Biometry

2016 ◽  
Vol 17 (4) ◽  
pp. 321-326
Author(s):  
Aleksandra Cvetkovic ◽  
Suncica Sreckovic ◽  
Marko Petrovic
Keyword(s):  
Intraocular Lens ◽  
Axial Length ◽  
Mean Values ◽  
Optical Biometry ◽  
Refractive Power ◽  
Number Of Patients ◽  
Significant Difference ◽  
Iol Power ◽  
The Mean ◽  
Lens Power

Abstract This study sought to compare the biometric values and intraocular lens (IOL) power obtained by standard ultrasound and optical biometry. We examined 29 eyes in preparation for cataract surgery. None of the patients had refractive surgery or corneal anomaly. In all patients, the horizontal and vertical refractive power of the cornea was determined using a keratometer (Bausch&Lomb). The axial length of the eye was determined via A-scan ultrasound (BVI-compact-V-plus) using Hollady’s formula. The IOL power and complete biometric measurements were obtained via an IOL Master-500-Zeiss using the Hollady-2 formula. All obtained values were compared and analysed using the statistical program SPSS 20. The average age of treated patients was 71.21±1.68 years. In 16 patients with dense cataracts (55.17%), it was not possible to determine the IOL power by optical biometry. Optical biometry obtained significantly increased axial length values of 24.04±0.29 mm compared with those obtained with ultrasound biometry (23.89±0.28 mm, p=0.003). The mean refractive cornea power values of the horizontal meridian measured using a keratometer (42.50±0.47 D) and an IOL Master (42.69±0.49 D) were not statistically different (p=0.187). The mean values of the refractive cornea power of the vertical meridian obtained using a keratometer (42.62±0.48D) and an IOL Master (43.36±0.51 D) exhibited a statistically significant difference (p=0.000). The keratometer obtained statistically significant lower mean values of corneal refractive power (42.73±0.32 D) compared with those obtained with optical biometry (43.22±0.35 D, p=0.000). Ultrasound biometry obtained significantly increased the mean values of IOL power (20.19±0.48D) compared with those obtained with optical biometry (19.71±0.48 D, p=0.018). The large number of patients who receive an operation for dense cataracts indicate the need for representation of both biometric methods in our clinical practice.

scholarly journals Treatment benefit among migraine patients taking fremanezumab: results from a post hoc responder analysis of two placebo-controlled trials

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Stephen D. Silberstein ◽  
Joshua M. Cohen ◽  
Ronghua Yang ◽  
Sanjay K. Gandhi ◽  
Evelyn Du ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Medication Use ◽  
Two Phase ◽  
Double Blind ◽  
Treatment Benefit ◽  
Mean Values ◽  
Treatment Benefits ◽  
Acute Headache ◽  
Post Hoc ◽  
Insight Into

Abstract Background Monoclonal antibodies targeting the calcitonin gene-related peptide (CGRP) pathway, including the fully humanized monoclonal antibody (IgG2Δa) fremanezumab, have demonstrated safety and efficacy for migraine prevention. Clinical trials include responders and nonresponders; efficacy outcomes describe mean values across both groups and thus provide little insight into the clinical benefit in responders. Clinicians and their patients want to understand the extent of clinical improvement in patients who respond. This post hoc analysis of fremanezumab treatment attempts to answer this question: what is the benefit in subjects who responded to treatment during the two, phase 3 HALO clinical trials? Methods We included subjects with episodic migraine (EM) or chronic migraine (CM) who received fremanezumab quarterly (675 mg/placebo/placebo) or monthly (EM: 225 mg/225 mg/225 mg; CM: 675 mg/225 mg/225 mg) during the 12-week randomized, double-blind, placebo-controlled HALO EM and HALO CM clinical trials. EM and CM responders were defined as participants with a reduction of ≥ 2 or ≥ 4 monthly migraine days, respectively. Treatment benefits evaluated included reductions in monthly migraine days, acute headache medication use, and headache-related disability, and changes in health-related quality of life (HRQoL). Results Overall, 857 participants from the HALO trials were identified as responders (EM: 429 [73.8%]; CM: 428 [56.7%]). Reductions in the monthly average number of migraine days were greater among EM (quarterly: 5.4 days; monthly: 5.5 days) and CM (quarterly: 8.7 days; monthly: 9.1 days) responders compared with the overall population. The proportion of participants achieving ≥ 50% reduction in the average monthly number of migraine days was also greater in responders (EM: quarterly, 59.8%; monthly, 63.7%; CM: quarterly, 52.8%; monthly, 59.0%) than in the overall population. Greater reductions in the average number of days of acute headache medication use, greater reductions in headache-related disability scores, and larger improvements in HRQoL were observed among EM and CM responders compared with the overall populations. Conclusions Fremanezumab responders achieved clinically meaningful improvements in all outcomes. The magnitude of improvements with fremanezumab across efficacy outcomes was far greater in responders than in the overall trial population, providing insight into expected treatment benefits in participants who respond to fremanezumab in clinical practice. Trial registration ClinicalTrials.gov identifiers: NCT02629861 (HALO EM) and NCT02621931 (HALO CM).

scholarly journals Changes in anterior segment optical coherence tomography following pars plana vitrectomy without tamponade

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Alireza Khodabande ◽  
Massood Mohammadi ◽  
Hamid Riazi-Esfahani ◽  
Shahab Karami ◽  
Massood Mirghorbani ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Anterior Chamber ◽  
Pars Plana Vitrectomy ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Optical Coherence ◽  
Mean Values ◽  
Iop Measurement ◽  
Pars Plana ◽  
The Mean

Abstract Background To evaluate changes in anterior segment morphology on anterior segment optical coherence tomography (AS-OCT) following pars plana vitrectomy (PPV) without tamponade. Methods Patients who underwent PPV without tamponade for epiretinal membrane were evaluated. Eligible patients underwent intraocular pressure (IOP) measurement and AS-OCT preoperatively as well as 1 month and 6 months post-operatively. Anterior chamber width (ACW), anterior chamber depth (ACD), trabecular iris angle (TIA), angle opening distance at 500 and 750 µm (AOD), and trabecular iris space area at 500 and 750 µm (TISA) at four quadrants were recorded and analyzed. Additionally, the mean values of TIA (MTIA), AOD (MAOD), and TISA (MTISA) for each eye (mean of four quadrants) were analyzed. Results 23 patients completed the study. The mean age of participants was 56.4 ± 3.6 years of age and 13/23 (56%) were female. Mean IOP of patients was 18.1 ± 1.1, 18.3 ± 1.1, and 18.1 ± 1.2 preoperatively,1 month post-operatively, and 6 months post-operatively, respectively. (p = 0.83). No difference was detected post-operatively in measurements of ACW, ACD, MTIA, MAOD500, MAOD750, MTISA500, and MTISA750. Conclusion Pars plana vitrectomy without tamponade was not associated with changes in anterior chamber morphology.

scholarly journals Intraocular lens power calculation for plus and minus lenses in high myopia using partial coherence interferometry

2021 ◽  
Author(s):  
Matthias Fuest ◽  
Niklas Plange ◽  
David Kuerten ◽  
Hannah Schellhase ◽  
Babac A. E. Mazinani ◽  
...  
Keyword(s):  
Axial Length ◽  
Absolute Error ◽  
Intraocular Lenses ◽  
Partial Coherence ◽  
Power Calculation ◽  
Partial Coherence Interferometry ◽  
Intraocular Lens Power Calculation ◽  
Hyperopic Shift ◽  
Lens Power ◽  
Lens Power Calculation

Abstract Purpose We assessed the accuracy of lens power calculation in highly myopic patients implanting plus and minus intraocular lenses (IOL). Methods We included 58 consecutive, myopic eyes with an axial length (AL) > 26.0 mm, undergoing phacoemulsification and IOL implantation following biometry using the IOLMaster 500. For lens power calculation, the Haigis formula was used in all cases. For comparison, refraction was back-calculated using the Barrett Universal II (Barrett), Holladay I, Hill-RBF (RBF) and SRK/T formulae. Results The mean axial length was 30.17 ± 2.67 mm. Barrett (80%), Haigis (87%) and RBF (82%) showed comparable numbers of IOLs within 1 diopter (D) of target refraction. Visual acuity (BSCVA) improved (p < 0.001) from 0.60 ± 0.35 to 0.29 ± 0.29 logMAR (> 28-days postsurgery). The median absolute error (MedAE) of Barrett 0.49 D, Haigis 0.38, RBF 0.44 and SRK/T 0.44 did not differ. The MedAE of Haigis was significantly smaller than Holladay (0.75 D; p = 0.01). All median postoperative refractive errors (MedRE) differed significantly with the exception of Haigis to SRK/T (p = 0.6): Barrett − 0.33 D, Haigis 0.25, Holladay 0.63, RBF 0.04 and SRK/T 0.13. Barrett, Haigis, Holladay and RBF showed a tendency for higher MedAEs in their minus compared to plus IOLs, which only reached significance for SRK/T (p = 0.001). Barrett (p < 0.001) and RBF (p = 0.04) showed myopic, SRK/T (p = 002) a hyperopic shift in their minus IOLs. Conclusions In highly myopic patients, the accuracies of Barrett, Haigis and RBF were comparable with a tendency for higher MedAEs in minus IOLs. Barrett and RBF showed myopic, SRK/T a hyperopic shift in their minus IOLs.

Sign in / Sign up

Export Citation Format

Share Document