scholarly journals Changes in ocular astigmatism after superotemporal versus temporal clear corneal incision cataract surgery

Author(s):  
Qi Fan ◽  
Dongjin Qian ◽  
Zhennan Zhao ◽  
Yongxiang Jiang ◽  
Yi Lu

Abstract Background The incision site to choose to manage postoperative astigmatism during cataract surgery is still debated. This study investigated corneal and internal astigmatism changes after superotemporal versus temporal clear corneal incision cataract surgery. Methods Patients included were diagnosed between December 2019 and January 2020 with age-related cataract with corneal astigmatism < 1.5 diopters (D) and were divided into two groups: Right Eye Group (R Group, superotemporal incision) and Left Eye Group (L Group, temporal incision). Uncorrected visual acuity, manifest refraction, corneal topography, anterior segment optical coherence tomography were performed pre- and 6 months postoperatively. Total ocular astigmatism, corneal astigmatism, surgically induced corneal astigmatism (SICA), non-corneal ocular residual astigmatism (N-CORA), postoperative intraocular lens (IOL) decentration, and tilt were analysed. Results Thirty-eight subjects were included: 21, R Group; 17, L Group. After surgery, the N-CORA decreased significantly from 1.17 ± 0.72D to 0.73 ± 0.47D in all patients (P = 0.001), 1.03 ± 0.52D to 0.70 ± 0.40D in the R Group (P = 0.005), and 1.35 ± 0.90D to 0.78 ± 0.55D in the L Group (P = 0.033). Significant differences between the R and L groups were found in the postoperative meridian of anterior corneal astigmatism (75.95 ± 52.50 vs 116.79 ± 47.29; P = 0.017), total corneal astigmatism (51.65 ± 42.75 vs 95.20 ± 57.32; P = 0.011), J45 change vector of SICA in the anterior cornea (-0.10 ± 0.18 vs 0.00 ± 0.11; P = 0.048), and total cornea surface (-0.14 ± 0.17 vs 0.03 ± 0.12; P = 0.001). IOL decentration, tilt, and the meridian of IOL tilt were not significantly correlated with N-CORA. Conclusions The N-CORA significantly decreased after cataract surgery. Superotemporal and temporal incisions can cause differences in the meridian components of oblique astigmatism but will not have a significant effect on the magnitude of corneal astigmatism.

2014 ◽  
Vol 2 (1) ◽  
pp. 22-27
Author(s):  
Md Shafiqul Alam ◽  
Khaleda Nazneen Bari

Background: Age related cataract is the leading cause of blindness and visual impairment throughout the world. With the advent of microsurgical facilities simple cataract extraction surgery has been replaced by small incision cataract surgery (SICS) with posterior chamber intra ocular lens implant, which can be done either with clear corneal incision or scleral incision. Objective: To compare the post operative visual outcome in these two procedures of cataract surgery. Materials and method: This comparative study was carried out in the department of Ophthalmology, Delta Medical College & Hospital, Dhaka, Bangladesh, during the period of January 2010 to December 2012. Total 60 subjects indicated for age related cataract surgery irrespective of sex with the age range of 40-80 years with predefined inclusion and exclusion criteria were enrolled in the study. Subjects were randomly and equally distributed in 2 groups; Group A for SICS with clear corneal incision and group B for SICS with scleral incision. Post operative visual out come was evaluated by determining visual acuity and astigmatism in different occasions and was compared between groups. Statistical analysis was done by SPSS for windows version12. Results: The highest age incidence (43.3%) was found between 61 to 70 years of age group. Among study subjects 40 were male and 20 were female. Preoperative visual acuity and astigmatism were evenly distributed between groups. Regarding postoperative unaided visual outcome, 6/12 or better visual acuity was found in 19.98% cases in group A and 39.6% cases in group B at 1st week. At 6th week 6/6 vision was found in 36.3% in Group A and 56.1% in Group B and 46.2% in group A and 66% in group B without and with correction respectively. With refractive correction, 6/6 vision was attained in 60% subjects of group A and 86.67% of group B at 8th week. Post operative visual acuity was statistically significant in all occasions. Postoperative astigmatism of >0.50D was in 82.5% subjects of group A and 52.8% subjects of group B at 1st week. At 6th week postoperative astigmatism of less than 1D was in 79.95% subjects of Group A and 83.34% subjects of Group B. About 20% subjects in Group A and only 3.3% in Group B showed astigmatism of more than 1D and these differences on both the occasions were statistically significant. Conclusion: The post operative visual outcome was better in SICS with scleral incision (group B) than in SICS with clear corneal incision (Group-A). DOI: http://dx.doi.org/10.3329/dmcj.v2i1.17793 Delta Med Col J. Jan 2014; 2(1): 22-27


2021 ◽  
Author(s):  
Dan Liu ◽  
Cong Fan ◽  
Chunyan Li ◽  
Jian Jiang

Abstract Background: Multifocal intraocular lenses (IOLs) is very intolerant to residual corneal astigmatism and patients with more than 1.0 D of residual corneal astigmatism are not suitable candidates for implantation of multifocal IOLs. The purpose of this study was to evaluate the efficacy of a single clear corneal incision (CCI) or an opposite clear corneal incision (OCCI) made on a steep meridian for correction of low to moderate corneal astigmatism during implantation of multifocal IOLs.Methods: This is a retrospective cohort study. A total of 50 patients with pre-operative total corneal astigmatism, ranging between 0.5 and 2.0 diopters (D), who underwent cataract surgery and received multifocal IOLs were included. Correction of corneal astigmatism was done via single CCIs on steep meridians in patients with 0.5–1.2 D total corneal astigmatisms, and OCCIs in patients with 1.3–2.0 D total corneal astigmatisms. Visual acuity, corneal astigmatism, ocular aberrations, corneal aberrations, and subjective vision quality were evaluated after surgery.Results: At 12-weeks post-surgery, the mean uncorrected distance vision (UCDV) was 0.06±0.09 logarithm of the minimum angle of resolution (logMAR) and 0.03±0.09 logMAR, and the mean uncorrected near vision (UCNV) was 0.08±0.11 logMAR and 0.09±0.09 logMAR in the CCI and OCCI groups, respectively. The change in corneal astigmatism was 0.52 ± 0.22D and 1.06 ± 0.23D in the CCI and OCCI groups, respectively (P<0.001). Total corneal higher-order aberrations (HOAs) and trefoil increased in both groups (P<0.05); however, there was no difference in the change in total corneal HOAs between the two groups (P>0.05). Conclusions: CCI and OCCI made on a steep axis could be an option for correction of mild-to-moderate astigmatism during cataract surgery with multifocal IOL implantation.


2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
Paul Ernest ◽  
Warren Hill ◽  
Richard Potvin

Purpose. To compare the surgically induced astigmatism from clear corneal and square posterior limbal incisions at the time of cataract surgery.Methods. Surgically induced astigmatism was calculated for a set of eyes after cataract surgery using a temporal 2.2 mm square posterior limbal incision. Results were compared to similar available data from surgeons using clear corneal incisions of similar size.Results. Preoperative corneal astigmatism averaged 1.0 D and was not significantly different between the incision types. Surgically induced astigmatism with the 2.2 mm posterior limbal incision averaged0.25±0.14 D, significantly lower in magnitude than the aggregate surgically induced astigmatism produced by the 2.2 mm clear corneal incision (0.68±0.49 D).Conclusion. The 2.2 mm square posterior limbal incision induced significantly less, and significantly less variable, surgically induced astigmatism relative to a similar-sized clear corneal incision. This is likely to improve refractive outcomes, particularly important with regard to premium intraocular lenses.


2020 ◽  
Vol 13 (12) ◽  
pp. 1895-1900
Author(s):  
Wei Chen ◽  
Jian Wu ◽  
Yong Wang ◽  
Jing Zhou ◽  
Rong-Rong Zhu ◽  
...  

AIM: To investigate the clinical efficacy and safety of femtosecond laser-assisted steepest-meridian clear corneal incisions for correcting preexisting corneal astigmatism performed at the time of cataract surgery. METHODS: This prospective case series study comprised consecutive age-related cataract patients with corneal regular astigmatism (range: +0.75 to +2.50 D) who had femtosecond laser-assisted steepest-meridian clear corneal incisions (single or paired). Corneal astigmatism was performed with the Pentacam preoperatively and 3mo postoperatively. Total corneal astigmatism and steepest-meridian measured in the 3-mm central zone were used to guide the location, size and number of clear corneal incision. The vector analysis of astigmatic change was performed using the Alpins method. RESULTS: Totally 138 eyes of 138 patients were included. The mean preoperative corneal astigmatism was 1.31±0.41 D, and was significantly reduced to 0.69±0.34 D (equivalent to difference vector) after surgery (P<0.01). The surgically-induced astigmatism was 1.02±0.54 D. The correction index (ratio of target induced astigmatism and surgically-induced astigmatism: 0.72±0.36) as well as the magnitude of error (difference between surgically-induced astigmatism and target induced astigmatism: -0.29±0.51) represented a slight under correction. For angle of error, the arithmetic mean was 1.11±13.70, indicating no significant systematic alignment errors. CONCLUSION: Femtosecond-assisted steepest-meridian clear corneal incision is a fast, customizable, adjustable, precise, and safe technique for the reduction of low to moderate corneal astigmatism during cataract surgery.


2019 ◽  
Vol 26 (01) ◽  
Author(s):  
MOHAMMAD Alam

Objectives: To evaluate the management of pre-existing astigmatism with 3.2 mm corneal incision on steeper axis during phacoemulsification cataract surgery. Study Design: Analytical study. Setting: Patients undergoing cataract surgery with phacoemulsification in K.D.A Teaching Hospital KMU-IMS Kohat. Period: January, 2016 to July, 2016. Materials and Methods: 50 patients with age related cataract were selected. Out of them 23 (46%) were male and 27 (54%) were female. All the patients were in age range from 49 to 76 years with mean age of 63.2% years. Proper examination with slit lamp was done. Informed consent was obtained from each patient. Proper proforma was made for documentation. Biometry was done for IOL power. Preoperative keratometry was done with Topcon autoref-keratometer. Patients with traumatic eyes, previously operated eyes, vascularised and opacified cornea were excluded from the study. Pupils of patients were dilated properly with tropicamide eye drop.  Phacoemulsification with 3.2 mm clear corneal incision at steeper axis with intraocular lenses implantation was carried out on all patients by single surgeon under topical anesthesia. Postoperative keratometry was done on the same keratometer and observer to avoid bias at the end of two months. Results: Preoperative astigmatism was present in range of 0.12 diopter cylinder to 3.71 diopter cylinder with mean 1.56 diopter cylinder. At the end of two months mean astigmatism of 0.98 diopter cylinder with range 0.2 diopter cylinder to 2.0 diopter cylinder was noted postoperatively with mean reduction of 0.58 diopter cylinder. Conclusion: Phacoemulsification with 3.2 mm clear corneal incision at steeper axis can correct astigmatism significantly with good emmetropic results.


2021 ◽  
Vol 8 ◽  
Author(s):  
Kazutaka Kamiya ◽  
Kei Iijima ◽  
Wakako Ando ◽  
Nobuyuki Shoji

Purpose: To compare the arithmetic mean of surgically induced astigmatism (M-SIA) and the centroid of surgically induced astigmatism (C-SIA) after standard cataract surgery.Methods: We retrospectively examined 200 eyes of 100 consecutive patients undergoing bilateral cataract surgery through a 2.8 mm temporal clear corneal incision. We quantitatively measured the magnitude and axis of corneal astigmatism preoperatively and 3 months postoperatively using an automated keratometer (TONOREFF-II, Nidek). We assessed the M-SIA, the C-SIA, and the double angle plots for the display of the individual SIA distributions.Results: For bilateral data analysis, the magnitude of corneal astigmatism significantly increased from 0.66 ± 0.39 D preoperatively to 0.74 ± 0.46 D postoperatively (paired t-test, p = 0.012). The M-SIA was 0.50 ± 0.36 D. On the other hand, the C-SIA was 0.18 ± 0.60 D at an axis of 97°. For unilateral analysis, we obtained similar outcomes between the right and left eye groups.Conclusions: According to our experience, standard cataract surgery induces the M-SIA by approximately 0.5 D. The magnitude of the C-SIA largely decreased to approximately 40% of the M-SIA, and the direction of the C-SIA showed a tendency toward with-the-rule astigmatism. It should be noted that the M-SIA was considerably different from the C-SIA, especially when selecting the appropriate toric IOL model and power.


2011 ◽  
Vol 04 (02) ◽  
pp. 92
Author(s):  
Dhivya Ashok Kumar ◽  
Amar Agarwal ◽  
◽  

We have reviewed the surgical technique, advantages, and limitations of sub-1 mm–700 micron cataract surgery or ‘microphakonit.’ The small clear corneal incision is made with the 0.8 mm microphakonit knife and the instruments, such as the phacoemulsification needle, irrigating chopper, and bimanual irrigation aspiration set, are made with a 0.7 mm diameter. We have also reviewed some of the work done by the authors in 700 micron cataract surgery and our analysis of microphakonit wound architecture has been explained. The clear corneal wound architecture in microphakonit has been evaluated with anterior segment optical coherence tomography and the healing process has been assessed. The microphakonit has proven to have early wound healing and less post-operative astigmatism as compared with the wound with extension.


2021 ◽  
Author(s):  
Dan Liu ◽  
Cong Fan ◽  
Chunyan Li ◽  
Jian Jiang

Abstract Background: Multifocal intraocular lenses (IOLs) is very intolerant to residual corneal astigmatism and patients with more than 1.0 D of residual corneal astigmatism are not suitable candidates for implantation of multifocal IOLs. The purpose of this study was to evaluate the efficacy of a single clear corneal incision (CCI) or an opposite clear corneal incision (OCCI) made on a steep meridian for correction of low to moderate corneal astigmatism during implantation of multifocal IOLs.Methods: This is a retrospective cohort study. A total of 80 patients with pre-operative total corneal astigmatism, ranging between 0.5 and 2.0 diopters (D), who underwent cataract surgery and received multifocal IOLs were included. Correction of corneal astigmatism was done via single CCIs on steep meridians in patients with 0.5–1.2 D total corneal astigmatisms, and OCCIs in patients with 1.3–2.0 D total corneal astigmatisms. Visual acuity, corneal astigmatism, ocular aberrations, corneal aberrations, and subjective vision quality were evaluated after surgery.Results: At 12-weeks post-surgery, the mean uncorrected distance vision acuity (UDVA) was 0.06±0.09 logarithm of the minimum angle of resolution (logMAR) and 0.03±0.09 logMAR, and the mean uncorrected near vision acuity(UNVA) was 0.08±0.11 logMAR and 0.09±0.09 logMAR in the CCI and OCCI groups, respectively. The change in corneal astigmatism was 0.52 ± 0.22D and 1.06 ± 0.23D in the CCI and OCCI groups, respectively (P<0.001). Total corneal higher-order aberrations (HOAs) and trefoil increased in both groups (P<0.05); however, there was no difference in the change in total corneal HOAs between the two groups (P>0.05). Conclusions: CCI and OCCI made on a steep axis could be an option for correction of mild-to-moderate astigmatism during cataract surgery with multifocal IOL implantation.


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