Ocular Biometry and Corneal Astigmatism in Patients Undergoing Cataract Surgery in Bheri Zone of Nepal

Introduction: Accurate measurement of ocular axial length, keratometry and anterior chamber depth before cataract surgery is crucial for calculating the power of intraocular lens (IOL) to be implanted. Corneal astigmatism is one of the major thefts to have best postoperative unaided visual acuity. Thus, knowing it preoperatively and taking appropriate intervention during surgery provides best postoperative visual outcome. But there are no studies on corneal astigmatism and biometric parameters in the population of Bheri Zone. MATERIAL AND METHOD: The medical records of the patients who had ndergone cataract surgery between January 2017 and November 2017 at Nepalgunj medical college were retrospectively reviewed and analyzed. Patient's demographic parameter, keratometric value, anterior chamber depth, lens thickness and axial length data were collected and analyzed. RESULTS: This study evaluated the data in 65 eyes of 65 patients who had undergone cataract surgery. The mean age of patients was 59.3 ± 15.71 years. The mean corneal astigmatism was 1.37 D ±1.4D (range 0.00-6.75D). Corneal astigmatism was higher than 1.00 D in 32.3% of cases. The mean average keratometry was 44.54±1.83D. The magnitude of corneal astigmatism was positively correlated with age (p<0. 001) and there was a tendency for corneal astigmatism to increase with age above 50 years. Against-the-rule regular astigmatism was the most common type (46.2%) of astigmatism observed in this study. CONCLUSION: The present report showed the pattern of corneal astigmatism before cataract surgery in the patients at Nepalgunj Medical College Teaching Hospital. One third of cataract patients had corneal astigmatism of more than 1.0D. This finding provide the important normative reference and help ophthalmologists to plan and manage the cost-effective correction of preexisting corneal astigmatism in cataract patients to achieve the best visual outcome.

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Evaluation of Anterior Chamber Depth in 28,709 Adult Cataract Patients in China using Swept-Source Optical Biometry

10.21203/rs.3.rs-200270/v1 ◽

2021 ◽

Author(s):

Qiong Lei ◽

Haixia Tu ◽

Xi Feng ◽

Yong Wang

Keyword(s):

Cataract Surgery ◽

Anterior Chamber ◽

Axial Length ◽

Corneal Thickness ◽

Anterior Chamber Depth ◽

Multivariate Regression Analysis ◽

Swept Source ◽

Mean Values ◽

The Mean ◽

Cataract Patients

Abstract Background: To create an anterior chamber depth (ACD) regression model for adult cataract surgery candidates from China, and to evaluate the distribution of their ocular biometric parameters.Methods: The ocular biometric records of 28,709 right eyes of cataract surgery candidates who were treated at Aier Eye Hospitals in nine cities from 2018 to 2019 were retrospectively analyzed. All measurements were taken with IOLMaster 700. We included patients who were at least 40 years old and were diagnosed with cataract.Results: The mean age of the patients was 68.6 ± 11.0 years. The mean values recorded were as follows: axial length (AL), 24.17 ± 2.47 mm; mean keratometry (Km) value, 44.09 ± 3.25 D; corneal astigmatism (CA), 1.06 ± 0.98 D; ACD, 3.02 ± 0.45 mm; lens thickness (LT), 4.52 ± 0.45 mm; central corneal thickness (CCT), 0.534 ± 0.04 mm; and white to white (WTW) corneal diameter, 11.64 ± 0.46 mm. The proportion of patients with long axial length (AL >25 mm) decreased with age. ACD, LT, AL, Km, WTW, and age were correlated. In the multivariate regression analysis of ACD, which included LT, AL, WTW, sex, Km, CCT, and age, there was a reasonable prediction with adjusted R2 = 0.629.Conclusions: The results show that high myopes are inclined to schedule cataract surgery at a younger age. LT and AL were found to be important factors that affect ACD. This study provides reference data for cataract patients from China.

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Preoperative Biometry and Uncorrected Visual Outcome Following Cataract Surgery at a Teaching Hospital at Western Part of Nepal

Journal of Nepalgunj Medical College ◽

10.3126/jngmc.v19i1.40260 ◽

2022 ◽

Vol 19 (1) ◽

pp. 64-68

Author(s):

Bikram Bahadur Thapa ◽

Basu Prasad Adhikari ◽

Nanda Kumari Gurung ◽

Jitendra Kumar Verma

Keyword(s):

Visual Acuity ◽

Cataract Surgery ◽

Anterior Chamber Depth ◽

Visual Outcome ◽

Corneal Astigmatism ◽

Small Incision Cataract Surgery ◽

Biometric Data ◽

Medical College ◽

Small Incision ◽

The Mean

Introduction: Proper preoperative biometry in cataract surgery provides expected postoperative uncorrected visual outcome. Astigmatism is one of the major problems to achieve best postoperative unaided visual acuity. Aims: To determine the distribution of biometric parameter and unaided visual outcome in the cataract patients operated at Nepalgunj medical college, Banke, Nepal. Methods: The patients who underwent cataract surgery between January 2019 and December 2020 at Nepalgunj medical college were studied. Patient’s demographic parameter, keratometric value, anterior chamber depth, lens thickness and axial length data, type of surgery, preoperative and post-operative visual acuity and other clinical details were collected and analyzed. Results: This study enrolled 261 eyes of 261 patients who had undergone cataract surgery. The mean age of patients was 60.8 ± 14.62 years. The mean corneal astigmatism was 1.30±1.43 D. Corneal astigmatism was higher than 1.00 D in almost 40% of cases. With-therule astigmatism was the most common type (46.4%) of astigmatism observed in this study. The mean average keratometry was 44.83±2.05 D. The mean preoperative LogMAR VA of 1.52±0.83 improved to 0.48 ± 0.48 postoperatively without statistically significant differences between manual small incision cataract surgery and phacoemulsification technique (p=0.496). Conclusion: The biometric data helps to improve surgical procedure and select most appropriate intraocular lens to attain maximal postoperative uncorrected visual acuity following cataract surgery. This study found superior convention incision is better for cataract surgery with equivalent visual outcome following manual small incision cataract surgery and phacoemulsification.

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Prevalence of Pre-Existing Corneal Astigmatism in Age Related Cataract Patient

Faridpur Medical College Journal ◽

10.3329/fmcj.v8i1.16887 ◽

2013 ◽

Vol 8 (1) ◽

pp. 02-04

Author(s):

Md Abdur Rashid ◽

KH Anowar Hossain ◽

AKM Rafiqul Islam

Keyword(s):

Prospective Study ◽

Cataract Surgery ◽

Visual Outcome ◽

Corneal Astigmatism ◽

Normal Vision ◽

College Hospital ◽

Medical College ◽

Cataract Patient ◽

Age Related ◽

The Mean

Cataract surgery is no more a blind rehabilitation surgery, it absolutely gives normal vision. In the era of modern cataract surgery patients expectations are also high about visual outcome. This prospective study was carried out to investigate the magnitude and pattern of pre-existing corneal astigmatism in age related cataract patient at Faridpur Medical College Hospital, Faridpur and Agha Yusuf Adhunik Hospital, Kustia, from July 2009 to June 2012. We examined 850 eyes of 730 patients who underwent cataract surgery. The mean age at the time of surgery was 61.9±8.1 (40 to 70) years. Corneal astigmatism was measured by Auto Refracto Keratometer at least two times for each patient. Astigmatism was calculated from diopteric difference of vertical reading from horizontal reading. With the rule (WTR) astigmatism was considered when steep meridian at 90°± 20°. Against the rule (ATR) astigmatism was considered when steep meridian at 180°±20°. Astigmatism is in other direction is defined as oblique. On keratometry, when vertical reading (k1) was found greater than horizontal (k2) was considered WTR astigmatism and the reverse reading for ATR astigmatism. The percentage of corneal astigmatism was 1D or less was 69.6%, more than 1D and less than 1.5D, 27.6% and more than 1.5D and less then 2D 2.8%. Prevalence of ATR astigmatism was more than WTR astigmatism and prevalence of ATR astigmatism increases significantly with age. Approximately two third of pre-operative patient had 1D or less astigmatism and one third had more than 1D corneal astigmatism. DOI: http://dx.doi.org/10.3329/fmcj.v8i1.16887 Faridpur Med. Coll. J. 2013;8(1): 02-04

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Comparison of Axial Length and Anterior Chamber Depth Measurement among Optical, Applanation and Immersion Biometry

Journal of Shaheed Suhrawardy Medical College ◽

10.3329/jssmc.v11i1.43182 ◽

2019 ◽

Vol 11 (1) ◽

pp. 59-64

Author(s):

Harun Ur Rashid ◽

AQM Omar Sharif ◽

Zinat Rehana Shipu ◽

Debashish Ghosh ◽

Sofia Akhter ◽

...

Keyword(s):

Cataract Surgery ◽

Anterior Chamber ◽

Axial Length ◽

Anterior Chamber Depth ◽

Power Calculation ◽

Strong Positive Correlation ◽

Care Hospital ◽

Optical Biometry ◽

Depth Measurement ◽

The Mean

Background: Precise biometry is one of the major key factors for obtaining desired refractive outcome after cataract surgery. Visual outcome strongly depends on accuracy of ocular parameters especially axial length (AL) and anterior chamber depth (ACD). It is very important to evaluate different biometry methods to have accurate measurements for IOL power calculation. Objective: The aim of the study is to compare and analyze the difference between the measurement of axial length (AL) and anterior chamber depth (ACD) using ultrasound applanation, immersion and optical biometry. Methodology: A prospective study conducted on 168 patients enrolled for cataract surgery from January 2018 to December 2018 in Dhaka Eye Care Hospital, Dhaka. 280 eyes have been tested by a single observer. Axial length (AL) and anterior chamber depth (ACD) was measured consecutively by optical, applanation and immersion biometry. The results have been statistically evaluated to establish efficacy and correlation among the three methods of biometry. Results: Statistical analysis showed the mean of axial length (AL) obtained from optical biometry is 23.36 ± 1.99 mm, which is 0.10mm (p=0.00) less by applanation biometry and 0.04 mm (p=0.00) less by immersion biometry. For anterior chamber depth (ACD), the mean value from optical biometry is 3.13 ± 0.47mm. This value is highest in compare to both applanation (0.002 mm less with p = 0.824) and immersion (0.04 mm less with p = 0.00) biometry. Further analysis reveals strong correlation of optical biometry with applanation biometry (r = 0.994 for AL and 0.945 for ACD) and immersion biometry (r = 0.995 for AL and 0.947 for ACD). Conclusion: The study reveals that among optical, applanation and immersion method the optical biometry method appeared to be the most precise way of measuring axial length (AL) and anterior chamber depth (ACD) of eye. The study also shows an excellent agreement and strong positive correlation of optical biometry with applanation and immersion biometry. J Shaheed Suhrawardy Med Coll, June 2019, Vol.11(1); 59-64

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Analysis of corneal astigmatism and aberration in chinese congenital cataract and developmental cataract patients before cataract surgery

BMC Ophthalmology ◽

10.1186/s12886-020-01794-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Xiaoyan Han ◽

Qi Fan ◽

Zhixiang Hua ◽

Xiaodi Qiu ◽

Dongjin Qian ◽

...

Keyword(s):

Cataract Surgery ◽

Congenital Cataract ◽

Anterior Chamber Depth ◽

Corneal Astigmatism ◽

Imaging Device ◽

Mean Values ◽

Biometric Parameters ◽

Developmental Cataract ◽

Positive Linear Correlation ◽

Cataract Patients

Abstract Background To investigate the distribution of corneal astigmatism, aberration, and biometric parameters in Chinese congenital cataract (CC) /developmental cataract patients before cataract surgery. Methods We evaluated eyes of CC /developmental cataract patients scheduled for cataract surgery from January 2016 to September 2019. Astigmatism, aberrations, and biometric parameters were measured with the Pentacam Scheimpflug imaging device (Pentacam HR, Oculus). Cataract was diagnosed and classified by slit-lamp examination after full mydriasis. Results We evaluated 538 eyes in 356 patients. The mean values of anterior corneal astigmatism (ACA), posterior corneal astigmatism (PCA), and total corneal astigmatism (TCA) were determined as 1.98 ± 1.06 D (range 0.0‒4.8 D), 0.49 ± 0.26 D (range 0.0‒1.9 D), and 2.09 ± 1.19 D (range 0.2‒8.8 D), respectively. ACA and TCA ≥ 1.25 D was present in 379 eyes (70.3%) and 392 eyes (72.8%), respectively. PCA between 0.25 D and 0.75 D was found in 380 eyes (70.6%). There was a statistically significant positive linear correlation between lower-order aberrations root mean square values (LOA RMS) and corneal astigmatism (CA). Furthermore, in terms of distribution of central cornea thickness, anterior chamber depth, ACA, PCA, and TCA in different types of cataracts, ACA was highest in patients with zonular cataracts. Finally, we found anterior corneal measurements may overestimate WTR astigmatism, underestimate ATR astigmatism, and underestimate oblique astigmatism, respectively. Conclusions Most CC /developmental cataract patients had moderate to high astigmatism and ACA accounted for the largest proportion in the zonular group. This can provide a basis for planning of CC/developmental cataract surgery by ophthalmologists in clinical practice.

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Factors affecting changes in the intraocular pressure after phacoemulsification surgery

International Eye Research ◽

10.18240/ier.2020.03.06 ◽

2020 ◽

Vol 1 (3) ◽

pp. 166-172

Author(s):

Rita Dhamankar ◽

◽

Suhas S Haldipurkar ◽

Tanvi Haldipurkar ◽

Vijay Shetty ◽

...

Keyword(s):

Intraocular Pressure ◽

Anterior Chamber ◽

Axial Length ◽

Anterior Chamber Depth ◽

The Other ◽

Factors Affecting ◽

Factors Associated ◽

Post Surgery ◽

Unit Increase ◽

The Mean

AIM: To assess the changes in anterior chamber parameters and examine the factors associated with changes in the intraocular pressure (IOP) in individuals who have undergone phacoemulsification surgery. METHODS: It is a longitudinal analysis of secondary clinical data collected from 105 non-glaucomatous eyes (82 patients) undergoing a cataract surgery. We studied the association between anterior chamber parameters, grade of cataract, demographics, and changes in the IOP over a period of three weeks. We also evaluated the association between the pressure-depth (PD) ratio and changes in the IOP during this time. RESULTS: The mean age (SD) of the 82 patients was 60.1±7.8y. The mean±standard deviation (SD) IOP was 15.06±3.36 mm Hg pre-operatively; it increased to 15.75±4.21 mm Hg on day one (P=0.20). In the multifactorial models, the mean IOP was -1.715 (95%CI: -2.795, -0.636) mm Hg on day 21±5 compared with the pre-operative values. The anterior chamber depth (ACD), axial length, age, sex, and grade of cataract were not significantly associated with changes in the IOP. Each unit increase in the PD ratio was associated with an increase in the mean IOP by 1.289 mm Hg (95%CI: 0.906, 1.671). After adjusting for pre-operative PD ratio, none of the other variables (ACD, axial length, temporal angle) were significantly associated with changes in mean IOP. CONCLUSION: The PD ratio was the single most important factor associated with the changes in post-operative IOP over three weeks post-surgery.

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A calculator proposal for estimating refractive error after 3 years using the onset biometric values in primary school children: a cohort study

10.22541/au.161971139.95061043/v1 ◽

2021 ◽

Author(s):

Feride Tuncer Orhan ◽

Haluk Huseyin Gürsoy

Keyword(s):

Primary School ◽

Anterior Chamber ◽

Refractive Error ◽

Axial Length ◽

Anterior Chamber Depth ◽

Primary School Children ◽

Optical Parameters ◽

Spherical Equivalent ◽

Final Data ◽

The Mean

Aim To evaluate consecutive measurements of the biometric parameters, age, and refraction error in a Turkish population at primary school age. Materials and Methods A total of 197 children aged between 7-12 years were included. The data of three consecutive measurements of children, who were examined at least once a year for three years using both cycloplegic auto-refractometry and optical biometry, were used in this retrospective study. Spherical equivalent <-0.50D was considered to be myopic; >+0.75D was considered to be hypermetropic. Age, gender, body mass index, spherical equivalent, axial length, anterior chamber depth, central corneal thickness, keratometry, and lens thickness were analyzed. The onset data obtained in 2013 whereas, the final data were from 2015. Logistic and Cox regression analyses were performed (p<0.05). Results The mean of the onset and the final spherical equivalents were 0.19D (0.56), and 0.08D (0.80), respectively. The myopia prevalence was increased among refractive errors in observation periods (univariable analysis p=0.029; multivariable analysis p=0.017). The onset axial length (HR:4.55, 95%CI:2.87-7.24, p<0.001), keratometry (HR:2.04, 95%CI:1.55-2.67, p<0.001) and age (HR:0.73, 95%CI: 0.57-0.92, p=0.009) correlated myopia progression. To calculate the estimated spherical equivalent, the onset data were included in the logistic regression model. The onset data of spherical equivalent (β=0.916, p<0.001), axial length (β=-0.451, p<0.001), anterior chamber depth (β=0.430, p=0.005) and keratometry (β=-0.172, p<0.001) were found to be significantly associated with the mean SE at the final data. Conclusions To calculate the estimated spherical equivalent following three years, an equation was proposed. The estimated refractive error of children can be calculated by using the proposed equation with the associated onset optical parameters.

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Clinical Analysis of Ocular Parameters Contributing to Intraoperative Pain during Standard Phacoemulsification

Journal of Ophthalmology ◽

10.1155/2017/9463871 ◽

2017 ◽

Vol 2017 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Yong Koo Kang ◽

Myung Jun Kim ◽

Hong Kyun Kim ◽

Bo Young Chun

Keyword(s):

Intraocular Pressure ◽

Anterior Chamber ◽

Axial Length ◽

Medical Records ◽

Demographic Data ◽

Anterior Chamber Depth ◽

Clinical Analysis ◽

Subjective Pain ◽

Intraoperative Pain ◽

The Mean

Purpose. To study the correlation between ocular parameters and subjective pain that patients perceived during phacoemulsification.Methods. Medical records of 142 patients who underwent standard phacoemulsification under topical anesthesia between March and August 2016 were retrospectively reviewed. The pain during phacoemulsification and 1 h after surgery was assessed and compared using a visual analog scale. In addition, demographic data, preoperative biometric parameters, and intraoperative surgical parameters were recorded.Results. Mean age of patients was 67.49 ± 12.50 years. The mean pain score was 2.26 ± 0.85 during phacoemulsification and 0.40 ± 0.69 postoperatively. Intraoperative pain was significantly associated with higher preoperative intraocular pressure (β = 0.220,P=0.016), greater anterior chamber depth (β = 0.210,P=0.028), and greater axial length (β = 0.181,P=0.043).Conclusions. To reduce the subjective pain when patients have high preoperative intraocular pressure, large anterior chamber depth, or great axial length, supplementary procedures may be required.

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Ocular biometry and power of intra ocular lens among cataract patients in rural Eastern Ethiopia

10.21203/rs.2.20424/v1 ◽

2020 ◽

Author(s):

MANDEFRO SINTAYEHU KASSA ◽

GIRUM W GESSESSE

Keyword(s):

Anterior Chamber ◽

Axial Length ◽

Anterior Chamber Depth ◽

Multiple Linear Regression Model ◽

P Value ◽

Corneal Curvature ◽

Ocular Lens ◽

Eastern Ethiopia ◽

Ocular Biometry ◽

The Mean

Abstract Background : The main objective of the study was to report on the main parameters of ocular biometry and Intra ocular lens power of patients attending a cataract surgical program in Eastern Ethiopia. Methods : The study was a cross sectional study on 765 eyes which were legible for cataract surgery during a mass eye camp conducted from April 04 to April 10, 2018 at Bisidimo Hospital,Eastern Ethiopia.Ocular biometric parameters such as axial length (AL), anterior chamber depth (ACD), mean corneal curvature (MCC) were measured using automated keratorefractometer(Retinomax) and Sonomed A - Scan. Analysis of variance and multivariate analysis were done to determine association of ocular biometry components with socio demography of the study subjects. Results : A total of 765 eyes were enrolled in this study. The mean corneal curvature and the mean anterior chamber depth were found to be 7.61 mm and 2.88mm respectively. The mean axial length was estimated to be 22.98 mm. The mean refractive power of Intra ocular lenses was calculated to be 19.34D. The mean axial length in females was shorter than that of males by 0.24 and this was statistically significant ( P - value = 0.01). Under multiple linear regression model gender had a statistically significant impact on the axial length. The mean Anterior chamber depth in males was also larger than that of females by nearly 0.1 and this was statistically significant (P - value = 0.001). Under multiple linear regression model both age and gender had a statistically significant impact on the anterior chamber depth. There was no a statistically significant difference on the mean Intra ocular lens power required for male and female patients.Conclusion : This study is the first of its kind to provide a larger population based normative data on the most important parameters of ocular biometry in Ethiopia.The female sex was a strong predictor of small axial length and shallow anterior chamber. Increasing age had no effect on the axial length but was found to be a stronger predictor of shallow anterior chamber. Key words : Axial length, Anterior chamber depth, Corneal curvature, Intra ocular lens.

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Influence of anterior chamber depth on postoperative refractive outcome in Chinese eyes

Asian Journal of Ophthalmology ◽

10.35119/asjoo.v16i2.366 ◽

2018 ◽

Vol 16 (2) ◽

pp. 79-85

Author(s):

Rachel SH Wong ◽

Keith Ong

Keyword(s):

Cataract Surgery ◽

Anterior Chamber ◽

Anterior Chamber Depth ◽

Demographic Variables ◽

Refractive Outcomes ◽

Positive Linear Correlation ◽

The Mean ◽

The Difference ◽

Linear Correlations ◽

Refractive Surprise

Aim or Purpose: This study aims to evaluate the refractive surprise (RS) after cataract surgery with various intraocular lens (IOL) formulas in eyes with very shallow or deep anterior chamber depth (ACD). Design: This is a prospective cohort study of patients from a private ophthalmology practice in Sydney. Methods: Thirty-one patients who had their cataract surgery in 2014 were included. The cohort consists of 20 eyes with ACD < 2.8 mm and 25 eyes with ACD > 3.2 mm. Patients’ demographic variables and their predicted refractive outcomes using the SRK-T, Haigis, Holladay 1, and Holladay 2 IOL formulas were collected. Actual refractive outcomes were obtained from consultations at least one-month postoperatively. RS was calculated from the difference between predicted refraction outcome of IOL formulas and the actual postoperative refraction achieved. Results: The linear correlations between ACD and RS were not significant (p > 0.05). In the group with ACD < 2.8 mm, the mean refractive surprise using SRK-T, Haigis, Holladay 1, and Holladay 2 formulas were -0.191 ± 0.541, -0.189 ± 0.444, -0.201 ± 0.449, and -0.154 ± 0.489 D, respectively. In the group with ACD > 3.2 mm, the mean refractive surprise using the IOL formulas were -1.364 ± 0.541, -1.420 ± 0.541, 0.027 ± 0.394, and -0.045 ± 0.343 D, respectively. Conclusion: The positive linear correlation between ACD and RS was weak. In eyes with ACD < 2.8 mm, the least RS was found with the Holladay 2 formula, while in eyes with ACD > 3.2 mm, this was found with Holladay 1.

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