scholarly journals Preliminary experiences with limbal relaxing incision for treatment of astigmatism during phacoemulsification

1970 ◽  
Vol 1 (2) ◽  
pp. 90-94 ◽  
Author(s):  
BR Sharma ◽  
A Kumar
Keyword(s):  
Visual Acuity ◽  
Analysis Method ◽  
Surgically Induced Astigmatism ◽  
Early Experiences ◽  
Postoperative Astigmatism ◽  
Uncorrected Visual Acuity ◽  
Induced Astigmatism ◽  
The Mean ◽  
Surgically Induced ◽  
Relaxing Incisions

Introduction: This small study relates our early experiences with the Limbal Relaxing Incision (LRI) for management of astigmatism in patients undergoing cataract surgery. Aims: To evaluate the efficacy of LRI in the management of primary astigmatism when combined with phacoemulsification. Subjects and methods: Limbal relaxing incisions were performed to correct primary astigmatism in 12 eyes of 12 cataract patients who underwent phacoemulsification as the primary procedure. The length and number of incisions were determined using the AMO LRI calculator software programme using Donnenfield and NAPA nomograms. Keratometric astigmatism was measured preoperatively and postoperatively on day 1 and after 3 weeks or more. Surgically-induced astigmatism (SIA) and the intended angle of error were evaluated by the vector analysis method. Preoperative and postoperative uncorrected visual acuity (UCVA) and best spectacle corrected visual acuity (BSCVA) were evaluated in each visit. Results: The mean age of patients was 52.92 ±10.91 years. There were 75 % male and 25 % female patients. The mean keratometric preoperative astigmatism was 2.08 ±1.05 diopter. The mean 1st postoperative day keratometric astigmatism was 1.74 ±1.32 diopter and the mean final keratometric astigmatism at 3 weeks postoperatively was 1.05± 0.68 diopter. The mean SIA on the 1st postoperative day was 2.97 ±1.72 diopter at 103.25±56.57 degree with intended angle of error 6.53±9.61 degree. The mean SIA on the 3rd postoperative week was 2.26±0.87 Diopter at 107.08±49.96 degrees with intended angle of error 2.90±7.87 degrees. Conclusion: Limbal relaxing incisions are effective method to reduce postoperative astigmatism with good predictability of intended angle. Keywords: limbal relaxing incision (LRI); uncorrected visual acuity (UCVA); surgically induced astigmatism (SIA); angle of error; target astigmatic treatment (TAT) DOI: 10.3126/nepjoph.v1i2.3681 Nep J Oph 2009;1(2):90-94

scholarly journals Comparison of surgically induced astigmatism between anterior and total cornea in 2.2 mm steep meridian incision cataract surgery

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Young-chae Yoon ◽  
Minji Ha ◽  
Woong-Joo Whang
Keyword(s):  
Cataract Surgery ◽  
Intraocular Lens ◽  
Corneal Surface ◽  
Polar Plot ◽  
Mean Values ◽  
Surgically Induced Astigmatism ◽  
Induced Astigmatism ◽  
The Mean ◽  
Surgically Induced ◽  
Corneal Refractive Power

Abstract Background This study aimed to compare surgically induced astigmatism (SIA) on the anterior and total cornea during cataract surgery through a 2.2 mm steep meridian incision. Methods The study included 69 left eyes of 69 patients who had undergone cataract surgery. The 69 eyes were classified into three subgroups according to the preoperative steep meridian. Following phacoemulsification, an intraocular lens was inserted into the bag. The keratometric measurements were taken 12 months postoperatively, on the anterior cornea (automated keratometer and anterior keratometry [K] from a rotating Scheimpflug camera) and total cornea (equivalent K reading [EKR] 3.0 mm, EKR 4.5 mm, total corneal refractive power (TCRP) 2.0 mm ring, TCRP 3.0 mm zone, TCRP 4.0 mm zone). The SIA was analyzed for each parameter. Results On the double-angle polar plot, the summated vector mean values of SIA determined by the automated keratometer and Scheimpflug anterior K were 0.28 diopter (axis: 177°) and 0.37 diopter (axis: 175°) in with-the-rule (WTR) astigmatism; 0.03 diopter (axis: 156°) and 0.18 diopter (axis: 177°) in oblique astigmatism; 0.15 diopter (axis: 96°) and 0.17 diopter (axis: 73°) in against-the-rule (ATR) astigmatism. The mean SIAs on the total cornea ranged from 0.31 to 0.42 diopter in WTR astigmatism; from 0.16 to 0.27 diopter in oblique astigmatism; from 0.04 to 0.11 diopter in ATR astigmatism. Mean magnitude SIA ranged from 0.41 to 0.46 diopter on anterior corneal surface and 0.50 to 0.62 diopter on total cornea. J0 and J45 of the posterior cornea showed no significant changes after cataract surgery, and the changes in J0 and J45 did not show any statistical differences between the anterior and total cornea (all p > 0.05). Conclusions There were no differences in the summed vector mean values of SIA between the anterior cornea and the total cornea.

scholarly journals Prediction of surgically induced astigmatism in manual and femtosecond laser-assisted clear corneal incisions

2018 ◽  
Vol 28 (4) ◽  
pp. 398-405 ◽  
Author(s):  
Joaquín Fernández ◽  
Manuel Rodríguez-Vallejo ◽  
Javier Martínez ◽  
Ana Tauste ◽  
David P Piñero
Keyword(s):  
Femtosecond Laser ◽  
Corneal Astigmatism ◽  
Toric Intraocular Lens ◽  
Surgically Induced Astigmatism ◽  
Orthogonal Components ◽  
Induced Astigmatism ◽  
The Mean ◽  
Surgically Induced ◽  
Corneal Incisions ◽  
Intraocular Lens Calculation

Purpose: To assess the surgically induced astigmatism with femtosecond laser-assisted and manual temporal clear corneal incisions and to evaluate the performance of a model for prediction of the surgically induced astigmatism based on the preoperative corneal astigmatism. Methods: Clinical data of 104 right eyes and 104 left eyes undergoing cataract surgery, 52 with manual incisions and 52 with femtosecond laser-assisted incisions in each eye group, were extracted and revised retrospectively. In all cases, manual incisions were 2.2 mm width and femtosecond incisions were 2.5 mm width, both at temporal location. A predictive model of the surgically induced astigmatism was obtained by means of simple linear regression analyses. Results: Mean surgically induced astigmatisms for right eyes were 0.14D@65° (manual) and 0.24D@92° (femtosecond) (p > 0.05) and for left eyes, 0.15D@101° (manual) and 0.19D@104° (femtosecond) (p > 0.05). The orthogonal components of the surgically induced astigmatism (XSIA, YSIA) were significantly correlated (p < 0.05) with the preoperative orthogonal components of corneal astigmatism (Xpreop, Ypreop) (r = −0.29 for X and r = −0.1 for Y). The preoperative astigmatism explained 8% of the variability of the XSIA and 3% of the variability of YSIA. The postoperative corneal astigmatism prediction was not improved by the surgically induced astigmatism obtained from the model in comparison with the simple vector subtraction of the mean surgically induced astigmatism. Conclusion: Temporal incisions induce similar astigmatism either for manual or for femtosecond procedures. This can be clinically negligible for being considered for toric intraocular lens calculation due to the great standard deviation in comparison with the mean. The usefulness of the prediction model should be confirmed in patients with high preoperative corneal astigmatism.

scholarly journals Posterior Corneal Asphericity Effect on Postoperative Astigmatism after EDOF Intraocular Lens Implantation in Cataract Patients

2021 ◽  
Vol 2021 ◽  
pp. 1-5
Author(s):  
Mark Rabinovich ◽  
Ivo Guber ◽  
Laëtitia Jessy Niegowski ◽  
Ana Maria Aramburu del Boz ◽  
Danial Al Khatib ◽  
...  
Keyword(s):  
Anterior Chamber Depth ◽  
Q Value ◽  
Corneal Surface ◽  
Surgically Induced Astigmatism ◽  
Postoperative Astigmatism ◽  
Corneal Asphericity ◽  
Induced Astigmatism ◽  
The Impact ◽  
Surgically Induced ◽  
Cataract Patients

Aim. To assess the impact of posterior corneal asphericity on postoperative astigmatism. Methods. We included retrospectively 70 eyes of 70 patients that underwent cataract surgery. We included data of the Q value, Kmax, K1, K2, astigmatism AL, and ACD. We performed a vectorial analysis to calculate the astigmatic vectors. Results. Seventy eyes were evaluated. 40 eyes were of females (58%) and 30 of males (42%). The average cohort age was 73 ± 8.9 years. Axial length (AL) was 23.5 ± 0.9, anterior chamber depth (ACD) was 3.13 ± 0.3, and the average posterior Q value was −0.35 ± 0.2. The only significant predictive variable for the correction index (CI) was the posterior Q value (r = 0.24, p  < 0.05) and for the surgically induced astigmatism (SIA) (β = 0.34, r = 0.58, p  < 0.05). Conclusion. Posterior corneal surface asphericity significantly influences the surgically induced astigmatism and the overcorrection for cataract patients after Lucidis EDOF IOL implantation.

scholarly journals A comparative study of sclero-corneal and clear corneal tunnel incision in manual small-incision cataract surgery

1970 ◽  
Vol 3 (1) ◽  
pp. 19-22
Author(s):  
S Archana ◽  
AK Khurana ◽  
U Chawla
Keyword(s):  
Visual Acuity ◽  
Cataract Surgery ◽  
Posterior Chamber ◽  
Small Incision Cataract Surgery ◽  
Surgically Induced Astigmatism ◽  
Small Incision ◽  
Group A ◽  
Induced Astigmatism ◽  
Group B ◽  
Surgically Induced

Background: Cataract surgery techniques have improved a lot over the years from couching to the latest micro-incision cataract surgery. Objectives: To compare the temporal sclero-corneal and clear corneal tunnel incisions in patients undergoing manual small-incision cataract surgery (SICS) with respect to the surgically-induced astigmatism. Materials and methods: The present study included 60 patients who underwent manual SICS with posterior chamber intraocular lens implantation. Group A comprised of 30 patients, selected randomly, who underwent sutureless manual SICS through 6 mm curvilinear clear corneal tunnel incision made temporally and Group B comprised of 30 patients, selected randomly, who underwent sutureless manual SICS through 6 mm straight sclero-corneal tunnel made temporally. The patients were assessed at 1 week, 2 weeks, 1 month and 2 months post-operatively and visual acuity and keratometry findings were recorded. The amount of surgically induced astigmatism was calculated using Holladay’s formula. Statistics: Numerical data were compared between the two groups using unpaired Student’s t-test. The p value of < 0.50 was considered significant. Results: The mean induced astigmatism in Group A was 2.69 ± 0.84 D at 1 week, 2.31 ± 0.77 D at 2 weeks; 2.03 ± 0.82 D at 4 weeks and 1.98 ± 0.54 D at 8 weeks post-operatively. In group B, it was 1.85 ± 0.62 D, 1.56 ± 0.54 D, 1.35 ± 0.49 D and 1.34 ±0.45 D at 1 week, 2 weeks, 4 weeks and 8 weeks postoperatively. Uncorrected visual acuity (UCVA) of 20/ 20 was seen in 20 % of patients in group A and in 40 % in group B at 8 weeks postoperatively. Conclusion: Surgically-induced astigmatism is significantly higher in clear corneal manual SICS than in sclero-corneal. Our study confirmed the safety and improvement in visual acuity after small-incision cataract surgery using sclero-corneal tunnel incision. Key words: astigmatism; sclero-corneal; clear corneal tunnel; extra-capsular cataract surgery; small incision cataract surgery DOI: 10.3126/nepjoph.v3i1.4273Nepal J Ophthalmol 2011;3(5):19-22

scholarly journals Surgically Induced Corneal Astigmatism Following Intravitreal Ranibizumab Injection

2015 ◽  
Vol 9 (1) ◽  
pp. 121-125
Author(s):  
Tolga Kocatürk ◽  
Erol Erkan ◽  
Sait Eğrilmez ◽  
Harun Çakmak ◽  
Sema O. Dündar ◽  
...  
Keyword(s):  
Mean Value ◽  
Point Of View ◽  
Age Related Macular Degeneration ◽  
Intravitreal Ranibizumab ◽  
Surgically Induced Astigmatism ◽  
Absolute Change ◽  
Age Related ◽  
Induced Astigmatism ◽  
The Mean ◽  
Surgically Induced

Purpose : To evaluate surgically induced astigmatism (SIA) after an intravitreal ranibizumab (IVR) injection. Methods : Fifty eight eyes of 58 patients who underwent IVR injection due to age-related macular degeneration (wet form) or macular edema were included in this study. Patients’ pre- and postoperative detailed ophthalmologic examinations were done and topographic keratometric values (K1, K2) were noted. Pre- and postoperative measurements were compared. Results : The mean preoperative astigmatism of 0.87 Diopters (D) was found to be 0.95 D, 0.75 D, 0.82 D and 0.78 D on the 1st day, 3rd day, 1st week and 1st month, respectively. After injection, absolute change in astigmatism was found to be 0.08 D, 0.12 D, 0.05 D and 0.09 D on the 1st day, 3rd day, 1st week and 1st month, respectively. The absolute change in astigmatism seemed to be insignificant in terms of refractive analysis, however; when we performed a vectorial analysis, which takes into account changes in the axis of astigmatism, the mean value of induced astigmatism were found to be 0.33±0.22 D, 0.32±0.29 D, 0.41±0.37 D, 0.46±0.32 D on the 1st day, 3rd day, 1st week and on 1st month, respectively. Conclusion : Intravitreal injection is a minimally invasive ophthalmologic procedure, however; it may still cause statistically significant induced astigmatism when evaluated from a vectorial point of view.

scholarly journals Pre-existing Corneal Astigmatism in patients undergoing Cataract Surgery in Western Nepal; A hospital-based Unicentered, Comprehensive, Prospective Observational Study

2020 ◽  
Vol 5 (2) ◽  
pp. 21-25
Author(s):  
Shristi Shrestha ◽  
Khemraj Kaini
Keyword(s):  
Visual Acuity ◽  
Cataract Surgery ◽  
Corneal Astigmatism ◽  
Cross Sectional ◽  
Postoperative Visual Acuity ◽  
Department Of Ophthalmology ◽  
Induced Astigmatism ◽  
Different Populations ◽  
The Mean ◽  
Surgically Induced

Introduction: Cataract surgery is one of the most commonly performed surgical procedures worldwide. The final postoperative visual acuity is dependent on the pre-existing corneal astigmatism, accurate biometry and surgically induced astigmatism. Because of the increase in the patient’s demand for better postoperative visual acuity, it becomes important to evaluate the distribution of pre-existing corneal astigmatism in different populations. The objective of the study was to analyze the magnitude and pattern of pre-existing corneal astigmatism in cataract surgery patients in Western Nepal.Methods: A hospital-based cross-sectional descriptive study was carried out in the Department of Ophthalmology, Manipal Teaching Hospital, Pokhara. Three hundred and two patients undergoing routine cataract surgery between February 2016 and January 2018 were recruited in the study. Keratometric data from these patients were collected and were analyzed using the statistical software SPSS version 21.Results: The mean age of the subjects was 70.25 ± 10.97 years (range 35 to 94 years). There was a preponderance of females (62%) over males (38%). The mean corneal astigmatism was 0.78 ± 0.59 D (range 0.00 to 5.00 D). The pre-existing corneal cylinder ≥ 1.00 D was seen in 40.06% of patients. The corneal astigmatism was mainly against the rule (65.56%). The amount of corneal astigmatism and corneal steepness increased with age.Conclusion: Corneal astigmatism of 1.00 D or more was seen in 40.06% of the patients undergoing cataract surgery which should be corrected to meet the patient’s expectation for good, unaided visual acuity after cataract surgery.

scholarly journals Keratometric astigmatism evaluation after trabeculectomy

2013 ◽  
Vol 5 (2) ◽  
pp. 215-219 ◽  
Author(s):  
Rashmi Kumari ◽  
BC Saha ◽  
LR Puri
Keyword(s):  
Mathematical Expression ◽  
Silk Suture ◽  
Interventional Study ◽  
Suture Materials ◽  
Surgically Induced Astigmatism ◽  
Vector Decomposition ◽  
Induced Astigmatism ◽  
The Mean ◽  
Surgically Induced ◽  
Time Point

Introduction: Post-operative astigmatism is one of the most important causes for diminution of vision after trabeculectomy. Objective: To evaluate the induced corneal astigmatism following trabeculectomy with the use of 8-0 silk suture. Materials and methods: A prospective interventional study was done including 100 consecutive eyes of 84 patients who underwent trabeculectomy with the use of 8-0 silk suture. The postoperative induced astigmatism on the 1st post-operative day, 3rd week and after 6 months was determined. Statistics: Vector analysis was performed on the data using a computerized method for calculating the surgically induced astigmatism (SIA) for each eye at every time point postoperatively. In order to analyze group changes, we also performed vector decomposition which gave us a mathematical expression of the changes in astigmatism “with the rule” (WTR) or “against the rule” (ATR). Results: The mean age of all the patients was 53.31 11.39 years. The mean 1st post-operative surgically induced astigmatism (SIA) was 2.73 D ( 99 degree ) which reduced to 0.41 D ( 58 degree) at the 3rd week and 0.43 ( 21 degree) at 6 months. The mean WTR astigmatism was 4.46 D and ART astigmatism was 1.42 D on the 1st post-operative day which was significantly high ( p<0.0001). At the 3rd week and 6 months WTR astigmatism ( 1.40 D and 1.08D ) and ATR astigmatism (1.27 D and 1.10 D) showed no significant changes (p=0.69,0.97 respectively. Conclusion: Trabeculectomy with the use of 8/0 silk sutures showed significantly high 1st post-operative day SIA which nevertheless perished fast to a minimum amount at just 3 weeks. Nepal J Ophthalmol 2013; 5(10): 215-219 DOI: http://dx.doi.org/10.3126/nepjoph.v5i2.8731

scholarly journals Randomized Controlled Trial of varied incision sites in Manual Small Incision Cataract Surgery done in a Medical College Hospital in Kancheepuram District, Tamil Nadu, India

2020 ◽  
Vol 5 (8) ◽  
pp. 237-242
Author(s):  
Dr. J. Samuel Cornelius Gnanadurai ◽  
◽  
Dr. S. Vimala Karunanidhi ◽  
Keyword(s):  
Visual Acuity ◽  
Cataract Surgery ◽  
Tamil Nadu ◽  
Controlled Trial ◽  
Age Group ◽  
Small Incision Cataract Surgery ◽  
Surgically Induced Astigmatism ◽  
Small Incision ◽  
Induced Astigmatism ◽  
Surgically Induced

Aim: To compare visual outcome, postoperative surgically induced astigmatism (SIA), andpostoperative complications of superior and temporal scleral incision in manual small incisioncataract surgery (MSICS). Materials and Methods: A Prospective Randomized, parallel-group,active-controlled Trial Study of 80 cases of senile/pre-senile cataract. 40 cases were randomlyassigned (computer-generated randomization) to superior incision and 40 cases to the temporalincision. Results: The majority of patients (38 patients- 47.5%) were in the age group of 56-65years. The next common age group was 66-75 years(31 patients-38.75%). In the superior MSICSgroup, the majority of patients (28 patients-70%) had a moderate post-operative unaided visualacuity of 6/18-6/12. In the temporal MSICS group, majority of patients(33patients-82.5%) had agood post-operative unaided visual acuity of 6/9-6/6. The mean surgically induced astigmatism(SIA)in the superior MSICS group was 1.12 and in the temporal MSICS group was 0.45 with a differenceof 0.67. The SIA values were analyzed using the unpaired T-test which showed a value of 9.967which was statistically significant(P value of 0.0001). Conclusion: This study has shown that thetemporal approach for Manual small incision cataract surgery(MSICS) has less postoperativeastigmatism and better postoperative unaided visual acuity compared to the superior approach.

Sign in / Sign up

Export Citation Format

Share Document