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Background: The purpose of this study is to compare axial length (AL) and the refractive outcome after phacoemulsification surgery from 2014 to 2019 at Hospital Sultanah Nur Zahirah, Terengganu, Malaysia. Method: This was a retrospective record review of all cataract patients who met the inclusion criteria and underwent uneventful superior wound phacoemulsification with nontoric intraocular lens (IOL) by a single surgeon from 2014 to 2019. Using optical biometry or immersion technique, the preoperative AL determined solely via the Sanders, Retzlaff and Kraff 2 (SRK2) formula was selected. The postoperative spherical equivalent (SE) at 6 weeks-12 weeks was retrieved. Using Statistical Package for the Social Sciences version 24.0, the mean differences between targeted and actual postoperative SE were analysed based on the AL. Result: In this study, 490 eyes of 472 patients aged 25 years old--88 years old (mean age 65.72 years old [SD 8.83]) were involved. There were 162 eyes (33%) in Group A (< 23 mm), 189 eyes (39%) in Group B (23.01 mm-24.0 mm) and 139 eyes (28%) in Group C (> 24.0 mm). The mean AL was 23.63 mm (SD 1.19). The mean differences between the targeted and actual postoperative SE were: -0.09 D (SD 0.60) in Group A, -0.07 D (SD 0.53) in Group B and -0.16 D (SD 0.52) in Group C. No significant difference was found between these groups (P = 0.327). Conclusion There was no significant difference in the refractive outcome using the SRK2 formula in different ALs after phacoemulsification surgery. Hence, there is no reason to modify or adjust the targeted SE based on AL. [ABSTRACT FROM AUTHOR]

Purpose: To determine the accuracy of different biometric formulae for intraocular lens power (IOL) calculation in predicting a target postoperative refraction within ± 1.0 diopters in patients with long axial length undergoing phacoemulsification. Study Design: Cross sectional study. Place and Duration of Study: Department of Ophthalmology and visual sciences, Unit 1 Dow University of Health Sciences, Dr. Ruth KM Phau Civil Hospital Karachi from February 2019 to August 2019. Methods: The study included 45 eyes with cataract and preoperative uncorrected visual acuity ranging from 6/60-6/12, axial length of 24.5 to 27.0 mm with no other ocular problem. IOL power was calculated with SRK-T, Holladay 1 and Haigis formula installed in optical biometer AL-Scan (Nidek Co, Ltd., Gamagori, Japan) and by Barrett universal 2 formula from http://www.apacrs.org/barrett_universal2/. Patients underwent phacoemulsification by single surgeon. Follow up included refractive status usingAutorefracto-keratometer,URK-700 (Unicos Co., Ltd., Korea) at 6th week post-operatively. Deviation of actual postoperative refraction from the predicted target preoperative refraction were calculated and values within ± 1.0 diopter were considered accurate. Data was analyzed using SPSS version 22. Results: Outcome in terms of postoperative refractive error (+1D to -1D) with respect to biometric formula showed 100% accuracy using Haigis formula, 90% accuracy using SRK-T formula, 72.72% accuracy using Barrett universal II formula and 66.67% accuracy using Holladay-1 formula. Conclusion: Haigis formula proved to be more reliable and accurate than SRK-T, Holladay 1 and Barrett universal II formulae for calculation of intraocular lens power in eyes with long axial length. [ABSTRACT FROM AUTHOR]

Purpose: To collate the accuracy of two recently introduced intraocular lens (IOL) formulas (VRF and VRF-G) in cataract patients using a swept-source optical coherence tomography (SS-OCT) biometry (IOL Master 700, Carl Zeiss Meditec AG, Jena, Germany).Patients and Methods: Data records of 295 eyes from 295 patients were included in this scrutiny. The IOLMaster 700 SS-OCT biometer was used for biometric measurements. The VRF and VRF-G formulas were compared with seven 3rd and 4th generation thin and thick-lens formulas: Haigis, Hoffer Q, Holladay 1, Holladay 2, SRK/T, T2, and Barrett Universal II. With optimized lens constants, the mean prediction error (PE) and its standard deviation (SD), the median absolute error (MedAE), the mean absolute error (MAE), and the percentage of eyes with PEs within ± 0.25 D, ± 0.50 D, ± 0.75 D, ± 1.00 D, and <± 2.00 D were analyzed.Results: Statistically significant differences were found between formulas in the whole group (Friedman test, P = 0.000). The VRF-G and Haigis formulas showed the lowest SD values (0.464 D and 0.466 D respectively). The VRF and Barrett Universal II formulas were less predictable (SD 0.471 D and SD 0.474 D respectively). The biggest proportion of eyes within ± 0.50 D was found with VRF-G (76.27%), Haigis (75.59%), VRF (74.92%), and Barrett Universal II (74.92%) formulas.Conclusion: Based on data achieved from the SS-OCT biometry, the VRF-G and Haigis methods were the more precise predictors of postoperative refraction with the biggest proportion of eyes within ± 0.50 D. [ABSTRACT FROM AUTHOR]

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Purpose: The aim of this study was to evaluate and compare the changes in Intraocular Pressure (IOP) and other ocular parameters: the Anterior Chamber Angle (ACA), Anterior Chamber Volume (ACV), and Anterior Chamber Depth (ACD) during phacoemulsification surgery in Greek patients with normotensive eyes and those with well-controlled Open-Angle Glaucoma (OAG). Additionally, parameters such as the Corneal Thickness (CCT), Axial Length (AL), Central Macular Thickness (CMT), and Retinal Nerve Fibre Layer (RNFL) were also examined. Patients and Methods: This was a prospective observational case–control study that included 50 phakic eyes, 25 normotensive (Group 1), and 25 with OAG: 15 Primary Open-Angle Glaucoma (POAG) and 10 Exfoliation Glaucoma (EXG) (Group 2). Ophthalmic assessment included IOP measurements, ocular biometry, and anterior and posterior segment optical coherence tomography evaluation of the aforementioned ocular parameters, prior and 6 months after phacoemulsification surgery. Results: At the 6 months post-operative review, a greater IOP reduction was recorded in eyes with OAG, in comparison to normotensive ones (5.3mmHg and 1.6 mmHg respectively). In addition, a significant but similar increase was recorded in the values of the ACA, ACV, and ACD of both groups between the pre- and the post-op period. Furthermore, the CCT and AL values remained unaltered. Finally, there was a non-statistically significant change in the mean CMT and the mean average RNFL of both groups. Conclusion: Eyes with OAG tend to undergo a greater reduction in IOP post-phacoemulsification surgery, in comparison to normotensive eyes. This reduction may not be solely attributed to ocular anatomical changes after phacoemulsification surgery but may also be due to the remodeling of the trabecular meshwork and the ciliary body. This may be especially true in the case of OAG eyes, which already start off with a compromised trabecular endothelium prior to surgery. [ABSTRACT FROM AUTHOR]

Background: To report long‐term biometric and refractive outcomes in a group of Danish children after surgery for childhood cataract. Methods: Children between 7 and 18 years who had undergone uni‐ or bilateral cataract surgery at the Department of Ophthalmology, Rigshospitalet, Denmark, were examined in this cross‐sectional study. Swept source optical coherence tomography (OCT) based optical biometry (IOLmaster 700) and anterior tomography (Pentacam) was performed. Healthy fellow eyes from those with unilateral cataract were used as controls. Results: We included 56 children in the study with a median age at surgery of 43.8 months (1.6–137.6). The amount of higher order aberrations was significantly increased in operated eyes (median root mean square 0.461 μm [range 0.264–1.484]) compared with non‐operated eyes (median root mean square 0.337 μm [range 0.162–0.498], p < 0.001). Younger age at surgery was positively associated with more higher order aberrations at follow‐up (p < 0.001), but we found no significant associations between the amount of higher order aberrations and visual acuity or contrast vision. Longer axial length was associated to glaucoma while shorter axial length was associated to strabismus (p < 0.001). Conclusions: Eyes operated for childhood cataract have higher order aberrations compared with non‐operated eyes. Higher order aberrations are complex refractive errors that cannot be corrected by normal lenses and may contribute to poor visual outcomes for the children. We found an association between young age at surgery and higher order aberrations. [ABSTRACT FROM AUTHOR]

Introduction: The evolution of modern technologies for cataract surgery has made it crucial for aiming emmetropia with highly defined vision. The key factor responsible for postoperative emmetropia is an accurate biometry, along with various other factors. Ultrasonic biometry is the gold standard method of Intraocular Lens (IOL) power calculation but the corneal indentation with the probe underestimate the axial length and result in a myopic shift which is overcome by the newer optical biometry devices, including swept source optical coherence biometry which uses infrared light to measure the ocular distances. Aim: To determine the precision and accuracy of IOL power calculation by ultrasound A-scan and optical IOL master and their refractive outcomes. Materials and Methods: This prospective, and observational study was conducted between September 2019 to February 2021 in 155 patients with cataract undergoing phacoemulsification in Kalinga Institute of Medical Sciences, KIIT University, Bhubaneswar, Odisha, India. All subjects underwent comprehensive ocular examination and biometry with two formulae {Sanders-Retzlaff-Kraff (SRK) and Holladay-I}. Biometry included corneal curvature (keratometry), axial length, anterior chamber depth, IOL power calculation, predicted refractive error. There were two broad groups. One group underwent biometry by ultrasound A-scan and the other group underwent optical biometry by IOL Master 700. The IOL power was calculated with the two formulae in both the groups. Comparisons between variables measured using the IOL master and A-scan were done using paired t-test. The p-values <0.05 were considered statistically significant. results: In a 18 month period, 155 eyes were consecutively enrolled in the study. The mean age of all enrolled patients was 62.1±8.65 years (range 34-80 years) with male:female ratio of approximately 1.25:1. The mean axial length measured by IOL master was higher (23.15 ± 0.85) than that by A-scan (22.96±0.81 diopters) with a mean difference of 0.197±0.35 mm (p-value <0.001, paired t-test). The mean predicted IOL power was 20.81±1.84 diopters by IOL master and 21.13±1.62 by A-scan by SRK-II formula (p-value <0.001). While mean predicted IOL power with Holladay-I by IOL Master 700 was 20.61±1.92 and 21.44±1.98 diopters by A-scan with a mean difference (-0.82±0.76 diopters) with a significant p-value <0.001. Bland-Altman analysis plots showed almost perfect agreement between both methods regarding predicted IOL power. conclusion: The swept source Optical Coherence Tomography (OCT) based IOL master 700 proved to be a faster non contact device to use with a shorter learning curve, higher accuracy in average axial length eye and less refractive surprises. [ABSTRACT FROM AUTHOR]

Aim The aim was to compare between the preoperative intraocular lens (IOL) power calculations accuracy measured by IOL Master vs applanation ultrasonic biometry in highly myopic and emmetropic eyes regarding postoperative refractive error. Patients and methods The IOL powers of 32 eyes of 32 patients prepared for phacoemulsification with IOL implantation were calculated preoperatively by IOL Master and A-scan. Postoperative refractive outcomes and spherical equivalent were compared with the predicted refractive error of each method. Results The mean±SD age of the 32 recruited patients was 53.91±10.21 years. The mean axial length (AXL) measured by IOL Master was higher (25.8±2.65 mm) than that with A-scan (25.46±3.43 mm), with a mean difference of 0.34±1.04 mm (P=0.2112). The mean predicted IOL power was 13.50±7.80 D with IOL Master vs 13.63±9.05 D with A-scan (P=0.930). However, no statistically significant difference was found regarding average K readings and predicted postoperative refraction (P=0.05 and 0.564, respectively). Further subgroup analysis revealed a statistically significant difference in AXL between both devices only in emmetropic group, with mean difference of 0.99±0.485 mm (P=0.00068). The mean absolute errors measured by IOL Master was 0.19±0.1417, whereas that of A-scan was 0.561±0.623. The mean difference between the two methods was −0.371 (P=0.0385), which was statistically significant. Discussion and conclusion The IOL Master AXL measurements were accurate, allowing more accurate calculation of the (IOL) power. It is user friendly, fast, with no contact with the corneal surface and with no possibility of damage to the surface or transmitting a disease.

Aim The aim was to compare between the preoperative intraocular lens (IOL) power calculations accuracy measured by IOL Master vs applanation ultrasonic biometry in highly myopic and emmetropic eyes regarding postoperative refractive error. Patients and methods The IOL powers of 32 eyes of 32 patients prepared for phacoemulsification with IOL implantation were calculated preoperatively by IOL Master and A-scan. Postoperative refractive outcomes and spherical equivalent were compared with the predicted refractive error of each method. Results The mean±SD age of the 32 recruited patients was 53.91±10.21 years. The mean axial length (AXL) measured by IOL Master was higher (25.8±2.65 mm) than that with A-scan (25.46±3.43 mm), with a mean difference of 0.34±1.04 mm (P=0.2112). The mean predicted IOL power was 13.50±7.80 D with IOL Master vs 13.63±9.05 D with A-scan (P=0.930). However, no statistically significant difference was found regarding average K readings and predicted postoperative refraction (P=0.05 and 0.564, respectively). Further subgroup analysis revealed a statistically significant difference in AXL between both devices only in emmetropic group, with mean difference of 0.99±0.485 mm (P=0.00068). The mean absolute errors measured by IOL Master was 0.19±0.1417, whereas that of A-scan was 0.561±0.623. The mean difference between the two methods was −0.371 (P=0.0385), which was statistically significant. Discussion and conclusion The IOL Master AXL measurements were accurate, allowing more accurate calculation of the (IOL) power. It is user friendly, fast, with no contact with the corneal surface and with no possibility of damage to the surface or transmitting a disease. [ABSTRACT FROM AUTHOR]

The understanding of correlations between different biometric parameters is essential for personalized eye care in the field of cataract and refractive surgery. This systematic review offers a clear overview of the previous literature assessing these correlations including a meta‐analysis. The review is focused on the following five correlations: (1) axial length and refractive error; (2) anterior chamber depth and refractive error; (3) axial length and anterior chamber depth; (4) corneal power and refractive error; (5) corneal power and axial length. An expected strong correlation between axial length and refractive error was found. Correlations including corneal power were weak and might be clinically insignificant. [ABSTRACT FROM AUTHOR]

Introduction: At present, refractive accuracy is the demand of cataract surgery which can be achieved by providing precise post-operative vision without spectacles. One of the important factors required to give spectacle free vision is calculation of accurate biometry. In developing countries like India, Small Incision Cataract Surgery (SICS) is done more commonly than phacoemulsification with foldable Intraocular Lenses (IOLs). Aim: To evaluate the accuracy of Immersion A-scan and Optical biometry in patients undergoing SICS with foldable IOLs by assessing their one month post-operative refraction and converting these values in predicted emmetropic IOL powers. Materials and Methods: Prospective study was conducted on 60 patients to be posted for cataract extraction in Department of Ophthalmology, Bharati Medical College and Hospital (Deemed to be university), Sangli, Maharashtra, India, for two months from the period of January 1, 2019 to March 1, 2019. Preoperatively patients were randomly divided in two groups containing 30 patients each, Group A was subjected to Immersion A-scan and Group B to Optical biometry. Patients included in the study preoperatively also underwent Best Corrected Visual Acuity (BCVA) estimation, applanation tonometry, slit lamp examination of anterior and posterior segment and Keratometry. Patients were examined post-operatively on 1st, 7th, and 30th day, for slit lamp examination of anterior and posterior segments and also their BCVA was noted. Final refraction was given on 30th postoperative day based on their auto-refractometer readings. Postoperative refraction and actual IOL power placed was used to calculate IOL power that would have produced emmetropia in that particular patient by the help of regression formula. Difference in actual IOL power placed and predicted emmetropic IOL power was also noted in each patient of both groups. Unpaired t-test was used for the statistical analysis. Results: The mean Axial Length (AXL) measured by immersion A-scan in group A was lesser (22.91 mm) than that with IOL master (23.15 mm) with a mean difference of 0.24 mm (p=0.133). Mean actual post-operative refraction at one month in group A was higher (0.90) than that of group B (0.70) with a mean difference of 0.20 (p=0.166). Mean difference between actual IOL (aIOL) placed and predicted emmetropic IOL (eIOL) was higher in group A (1.35) than that of group B (0.96) with a mean difference of both group was 0.39 (p=0.021). Conclusion: In the range of AXL 22 mm to 24.50 mm, used in this study, there is no statistically significant difference in axial length measurements between two methods of Ultrasound biometry and Optical biometry. Patients in Group A of present study had significant post-operative residual refraction as compared to Group B patients, which can be attributed to inaccurate Keratometry as two different methods of Keratometry were done in two groups. Keratometry values can influence post-operative refraction and inaccurate Keratometry may land with post-operative refractive errors. Current study showed certain advantages of optical biometry over USG biometry in that Optical biometry is Non-contact, fast and accurate, but optical biometry cannot be done in mature cataracts and dense posterior subcapsular cataract where immersion USG biometry is required. [ABSTRACT FROM AUTHOR]

Objective: The primary aim of this study was measure and compare the axial length (AXL), keratometric indices (K1, K2) and anterior chamber depth (ACD) by biometric devices; IOL Master and OB 820, to seek evidence on level of agreement for these parameters between these two devices. Study Design: Quasi-experimental study. Place and Duration of Study: Armed Forces Institute of Ophthalmology, Rawalpindi Pakistan, from Jul 2016 to Apr 2018. Methodology: This study was carried out at Armed Forced Institute of Ophthalmology on seventy eyes of 53 patients with senile grade II and grade III cataract. All patients underwent comprehensive ophthalmic and biometric examination using two different optical biometry devices the IOL-Master (Carl Zeiss Meditec, Jena, Germany) and OB-820 (Wave Light, Germany). Parameters of study were axial length (AXL), kera to metric indices (K1, K2) and anterior chamber depth (ACD). The results were evaluated using Bland-Altman analyses for level of agreement (LoA). The differences between both methodologies were assessed using the paired samples t test, and their correlation was evaluated by intra class correlation coefficient (ICC). Results: The mean age was 62.97 ± 7.97 years with the male/female ratio of 28/25. Mean axial length assessed by OB820 and IOL Master differed significantly in two groups, with a p-value of 0.018. Bland-Altman analysis further confirm significant difference range and 95% limits of agreement and ICC=0.659) of agreement for AXL. While, other parameters, K1, K2 and ACD showed an outstanding agreement (range within 95% confidence interval by Bland-Altman analysis) and internal consistency and reliability (ICC=0.960, 0.968. 0.976 respectively). Conclusion: The IOL-master and OB-820 should not be used interchangeably due to lack of agreement in axial length measurement the most important parameter for biometry. Both devices may provide consistent results regarding keratometry K1, K2 and ACD. [ABSTRACT FROM AUTHOR]

PurposeCalculation of intraocular lens (IOL) power for implantation during cataract surgery depends on ocular biometric measurements. The aim of this study was to characterise the normal range of intra- and interindividual variation in axial length (AL) and corneal power (K) when IOLMaster measurements were possible and to derive recommendations as to which outlying measurements merit verification before acceptance.MethodsThe Medisoft electronic patient database contains prospectively collected data conforming to the United Kingdom (UK) Cataract National Dataset on 55 567 cataract operations. From this AL and Kinformation on the 32 556 eyes (14 016 paired) of patients older than 25 years, without corneal pathology, history of intraocular surgery and who had all biometric measurements taken with the Zeiss IOLMaster (Carl Zeiss Meditec) were extracted. R 2.8.1 (R Foundation for Statistical Computing) was used for statistical analysis.ResultsMean age was 76.4 years and 62.0% were female. Mean (95% confidence interval) values for AL, mean Kand corneal astigmatism were 23.40 (21.27–26.59) mm, 43.90 (40.94–47.01) D and 1.04 (<2.50) D. Nearly all astigmatism was either with or against the rule. Differences between paired eyes were not statistically significant. 95% individuals had asymmetry of AL and mean K<0.70 mm and 0.92 D, respectively.ConclusionsOn the basis of approximation of the 95% CI above, it is suggested that AL, mean Kand keratometric astigmatism measurements outside the ranges 21.30–26.60 mm, 41.00–47.00 D and >2.50 D, respectively, and intraindividual asymmetry of AL >0.70 mm or mean K>0.90 D should be verified before acceptance. [ABSTRACT FROM AUTHOR]

PurposeTo assess the reliability of IOLMaster in axial length (AL) measurement in phakic silicone oil-filled vspseudophakic saline-filled eyes.MethodsTen eyes of 10 patients, vitrectomized with silicone oil tamponade and scleral buckled with significant lens opacity were enrolled. Optical biometry with IOLMaster (Carl Zeiss Meditec AG, Germany) was performed 1 day before and 1 week after silicone oil removal and phacoemulsification with artificial intraocular lens (IOL) implantation in order to assess changes in AL measurements.ResultsMean AL was 26.16±1.23 mm (range 24.64–28.8 mm) and 26.27±1.46 mm (range 25.26–29.6 mm), respectively, the day before and 1 week after silicone oil removal and cataract surgery, and the difference was not statistically significant (P=0.2).ConclusionsPresence vsabsence of silicone oil tamponade as well as phakic vspseudophaphakic status in buckled and vitrectomized eyes did not influence the AL measurement by means of no-contact optical biometry, suggesting that such eyes might be candidate for silicone oil removal and cataract surgery at one time.Eye (2007) 21, 909–911; doi:10.1038/sj.eye.6702452; published online 28 July 2006 [ABSTRACT FROM AUTHOR]