Effect of 1.8-mm steep-axis clear corneal incision on the posterior corneal astigmatism in candidates for toric IOL implantation

Abstract PURPOSE In the present study, we aimed to analyze the effects of cataract surgery using a 1.8-mm steep-axis clear corneal incision (CCI) on the posterior corneal surfaces based on the keratometry from the rotating Scheimpflug imaging device (Pentacam HR) in candidates for toric intraocular lens (IOL) implantation. METHODS Preoperative and at least 1-month postoperative data measured by Pentacam HR were collected in patients for toric IOL implantation. Surgically induced astigmatism on the posterior cornea (P-SIA) was calculated based on the preoperative and postoperative keratometric data, and the related factors of P-SIA were analyzed. RESULTS A total of 60 eyes from 56 patients were enrolled. The preoperative anterior and posterior corneal astigmatism was 1.58±0.61 D and 0.28±0.22 D, respectively. The postoperative anterior and posterior corneal astigmatism was 1.26±0.68 D and 0.41±0.26 D, respectively. The astigmatism was significantly decreased on anterior surface (P<0.001, paired t-test) and increased on posterior surface (P<0.001, paired t-test). The mean of P-SIA calculated by Holladay–Cravy–Koch method was 0.34±0.20 D, with 0.5 D or greater accounting for 26.7%. P-SIA showed no significant difference among with-the-rule (WTR) astigmatism, against-the-rule (ATR) astigmatism and oblique astigmatism (F=1.85, P=0.167). A statistically significant correlation was observed between the P-SIA and preoperative anterior corneal astigmatism (r = 0.29, P=0.024), as well as preoperative posterior corneal astigmatism (r=0.27, P=0.038). CONCLUSIONS In candidates for toric IOL implantation with a 1.8-mm steep-axis CCI, the incision caused a significant reduction of the anterior corneal astigmatism but an increase of the corneal posterior astigmatism. P-SIA could not be ignored, and it played a significant role in SIA, especially in cases with higher preoperative anterior or posterior corneal astigmatism.

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Effect of 1.8-mm steep-axis clear corneal incision on the posterior corneal astigmatism in candidates for toric IOL implantation

10.21203/rs.2.24131/v2 ◽

2020 ◽

Author(s):

Xi Li ◽

Xiang Chen ◽

Suhong He ◽

Wen Xu

Keyword(s):

Corneal Astigmatism ◽

Corneal Incision ◽

Toric Iol ◽

Iol Implantation ◽

Clear Corneal Incision ◽

Paired T Test ◽

Anterior Posterior ◽

Anterior Corneal Astigmatism ◽

Posterior Corneal Astigmatism ◽

Total Corneal Astigmatism

Abstract Background: In the present study, we aimed to analyze the effects of cataract surgery using a 1.8-mm steep-axis clear corneal incision (CCI) on the posterior corneal surfaces based on the keratometry from the rotating Scheimpflug imaging device (Pentacam HR) in candidates for toric intraocular lens (IOL) implantation. Methods: Preoperative and at least 1-month postoperative data measured by Pentacam HR were collected in patients for toric IOL implantation. Surgically induced astigmatism on the posterior cornea (P-SIA) was calculated based on the preoperative and postoperative keratometric data, and the related factors of P-SIA were analyzed. Results: A total of 60 eyes from 56 patients were enrolled. The preoperative anterior, posterior and total corneal astigmatism was 1.58±0.61 D ,0.28±0.22 D and 1.70 ± 0.52 D respectively. The postoperative anterior, posterior and total corneal astigmatism was 1.26±0.68 D, 0.41±0.26 D and 1.30 ± 0.51 D respectively. The astigmatism was significantly decreased on anterior surface (P＜0.001, paired t-test) and increased on posterior surface (P＜0.001, paired t-test). The mean of P-SIA calculated by Holladay–Cravy–Koch method was 0.34±0.20 D, with 0.5 D or greater accounting for 26.7%. A statistically significant correlation was observed between the P-SIA and preoperative anterior corneal astigmatism (r = 0.29, P=0.024), as well as preoperative posterior corneal astigmatism (r=0.27, P=0.038). Multivariate regression analysis showed the preoperative anterior and posterior corneal astigmatism had a significant effect on P-SIA (F=7.344, P=0.001). Conclusions: In candidates for toric IOL implantation with a 1.8-mm steep-axis CCI, the incision caused a significant reduction of the anterior corneal astigmatism but an increase of the posterior corneal astigmatism. P-SIA could not be ignored, and it played a significant role in SIA, especially in cases with higher preoperative anterior or posterior corneal astigmatism.

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Faculty of 1000 evaluation for Effect of steepest-meridian clear corneal incision for reducing preexisting corneal astigmatism using a meridian-marking method or surgeon's intuition.

F1000 - Post-publication peer review of the biomedical literature ◽

10.3410/f.718154811.793489343 ◽

2014 ◽

Author(s):

Shahzad Mian ◽

Christopher Hood

Keyword(s):

Corneal Astigmatism ◽

Corneal Incision ◽

Clear Corneal Incision

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Clinical differences between toric intraocular lens (IOL) and monofocal intraocular lens (IOL) implantation when myopia is determined as target refraction

10.21203/rs.3.rs-54189/v1 ◽

2020 ◽

Author(s):

Da young Shin ◽

Ho Sik Hwang ◽

Hyun Seung Kim ◽

Man Soo Kim ◽

Eun Chul Kim

Keyword(s):

Visual Acuity ◽

Intraocular Lens ◽

Corneal Astigmatism ◽

Spherical Equivalent ◽

Toric Intraocular Lens ◽

Toric Iol ◽

Iol Implantation ◽

Monofocal Iol ◽

Target Refraction ◽

Better Than

Abstract Background: To analyze and compare the clinical results of toric intraocular lens (IOL) and monofocal IOL implantation when the target refraction value is determined -3 diopter (D) in cataract patients with corneal astigmatism >1.5 diopters (D).Methods: We performed a retrospective chart review for patients with corneal astigmatism >1.5D who underwent cataract surgery and their target refraction is determined -3D. 100 eyes (100 patients; monofocal IOL, 60; toric IOL, 40) were enrolled in the current study. Near and distant uncorrected visual acuity (UCVA), corrected VA, spherical equivalent and refractive, corneal astigmatism were evaluated before and after surgery.Results: The near UCVA of the toric IOL group (0.26±0.33) after cataract surgery was significantly better than that of the monofocal IOL group (0.48±0.32) (p=0.030). The distant UCVA of the toric IOL group (0.38 ± 0.14) was also significantly better than that of the monofocal IOL group (0.55 ± 0.22) (p = 0.026). There were no significant intergroup differences in postoperative best-corrected visual acuity (p = 0.710) and mean spherical equivalent (p = 0.465). In the toric IOL group, postoperative refractive astigmatism was -0.80 ± 0.46D and postoperative corneal astigmatism was -1.50 ± 0.62D, whereas the corresponding values in the monofocal IOL group were -1.65 ± 0.77D and -1.45 ± 0.64D; residual refractive astigmatism was significantly lower with toric IOL implantation compared with monofocal IOL implantation (p = 0.001). Conclusions: When myopic refraction such as -3D was determined as the target power in patients with corneal astigmatism, toric IOL implantation led to excellent improvement in both near and distant UCVA.

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Two Different Corneal Incision Designs for Correcting Corneal Astigmatism During Cataract Surgery With Multifocal Intraocular Lens Implantation

10.21203/rs.3.rs-460872/v1 ◽

2021 ◽

Author(s):

Dan Liu ◽

Cong Fan ◽

Chunyan Li ◽

Jian Jiang

Keyword(s):

Cataract Surgery ◽

Corneal Astigmatism ◽

Intraocular Lenses ◽

Corneal Incision ◽

Multifocal Iol ◽

Clear Corneal Incision ◽

Corneal Aberrations ◽

Multifocal Intraocular Lenses ◽

Post Surgery ◽

The Mean

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.

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Corneal incision on steepest meridian in phacoemulsification, could it correct the corneal astigmatism?

10.21203/rs.3.rs-259772/v1 ◽

2021 ◽

Author(s):

Hossam Eldin Abdelmonem Ziada

Keyword(s):

Corneal Astigmatism ◽

Tunnel Length ◽

Corneal Incision ◽

Clear Corneal Incision ◽

Mild Degree ◽

Correction Of Astigmatism ◽

Iol Power ◽

Private Eye ◽

A Prospective Study

Abstract Introduction: Cataract surgery is regarded as refractive surgery when we are aiming at eliminating corneal astigmatism. So when planning a surgery both spherical and astigmatic components should be taken into account to achieve emmetropia postoperativelyPurpose: Measuring the changes of keratometric reading (K1, K2) after phacoemulsification surgery with planned incision on the steepest meridian in 50 eyes presenting as well with corneal astigmatism checking if this planned incision on steepest meridian could be an effective method or not to decrease the corneal astigmatism.Patients and Methods: A prospective study included 50 eyes of 35 patients that had immature senile cataract with corneal astigmatism more than 1 Diopter. Patients had been recruited and followed up in private eye center in Cairo. Phacoemulsification was done in all cases with placing the main clear corneal incision (0.5 mm from anatomical limbus, 2 mm tunnel length, 3 mm widths) on the steepest meridian. Follow up of patients included UCVA and BCVA at recorded 3 visits; 1 week, 1 month and 3months postoperatively, K-reading changes after 3 months postoperatively detected with pentacam, also, slit-lamp to assess both anterior and posterior segments.Results: this study showed a statistically significant change of front corneal astigmatism of 0.70 D and of 0.07 D of back corneal astigmatism.Conclusion: This method is effective in mild degree corneal astigmatism (up to 1D), while higher degree of astigmatism may need different method of intervention to be more effective in correction of astigmatism. We recommended measuring the IOL power depending on expected postoperative keratometric reading.

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Comparison of Astigmatism Correction in Cataract Surgery Between Simultaneous Femtosecond Laser-Assisted Intrastromal Arcuate Keratotomy and Toric Intraocular Lens Implantation

10.21203/rs.3.rs-58747/v1 ◽

2020 ◽

Author(s):

Hye Ji Kwon ◽

Hun Lee ◽

Jin Ah Lee ◽

Jae Yong Kim ◽

Hungwon Tchah

Keyword(s):

Femtosecond Laser ◽

Cataract Surgery ◽

Intraocular Lens ◽

Tertiary Care ◽

Corneal Astigmatism ◽

Toric Intraocular Lens ◽

Toric Iol ◽

Iol Implantation ◽

Tertiary Care Medical Center ◽

Significant Difference

Abstract Objectives To compare the efficacy of astigmatic correction between simultaneous femtosecond laser-assisted intrastromal arcuate keratotomy (AK) combined with femtosecond laser-assisted cataract surgery (FLACS) and toric intraocular lens (IOL) implantation during cataract surgery in moderate astigmatism. Design: Retrospective observational study, tertiary care medical center Methods We retrospectively reviewed medical records of patients who underwent astigmatic correction via femtosecond laser-assisted intrastromal AK (AK group; 27 eyes of 27 patients) with FLACS or toric IOL implantation (toric IOL group; 21 eyes of 21 patients). All patients had senile cataracts with corneal astigmatism ranging from + 1.00 to + 2.00 diopters (D) before cataract surgery. We measured visual acuity, intraocular pressure, automated keratometry, manifest refraction and topography preoperatively and at 1-day, 1-month, 3-month, and 6-month postoperatively. Results Refractive astigmatism was significantly decreased in both groups. The mean preoperative and 6-month postoperative refractive astigmatism were 1.85 ± 1.07 and 0.99 ± 0.51 D, respectively, in the AK group (P = 0.028), and 1.84 ± 0.81 and 0.68 ± 0.21 D, respectively, in the toric IOL group (P < 0.001). There was no significant difference in refractive astigmatism between the two groups at 6-month postoperatively (0.99 ± 0.51 vs 0.68 ± 0.21 D, P = 0.057). At 6-month postoperatively, parameters for vector analysis of refractive astigmatism showed no statistical difference between the two groups. Corneal astigmatism was significantly decreased in the AK group. There was significant difference in corneal astigmatism from topography and automated keratometer between the two groups at 6-month postoperatively (0.94 ± 0.40 vs 1.53 ± 0.46 D, P = 0.018 for topography and 0.98 ± 0.69 vs 1.37 ± 0.41 D, P = 0.032 for automated keratometer). Conclusions Femtosecond laser-assisted intrastromal AK in FLACS could be an effective procedure for reducing astigmatism as well as toric IOL implantation in cataract surgery.

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Scleral tunnel based sutureless extracapsular cataract extraction: An approach to astigmatic correction in soft cataracts of nuclear sclerosis grade 1

Indian Journal of Medical Sciences ◽

10.25259/ijms_315_2020 ◽

2020 ◽

Vol 0 ◽

pp. 1-6

Author(s):

Narendra Kumar Keisham ◽

Anil Sharma

Keyword(s):

Cataract Extraction ◽

Corneal Astigmatism ◽

Control Group ◽

Extracapsular Cataract Extraction ◽

Structural Protein ◽

Corneal Incision ◽

Clear Corneal Incision ◽

Scleral Tunnel ◽

Younger Age ◽

Age Profile

Objectives: A study to see if scleral tunnel based sutureless extracapsular cataract extraction with superior quadrant approach can correct pre-existing corneal astigmatism in soft cataracts of non-structural protein 1 (NS1) grade nuclear sclerosis in patients of younger age profile having “with-the-rule” pattern of corneal astigmatism. Material and Methods: 47 eyes of 41 patients who underwent scleral tunnel based sutureless extracapsular cataract extraction were taken as the study group and a second group of 44 eyes of 38 patients who underwent clear corneal incision based phacoemulsification surgery formed the control group. Soft cataracts of NS1 grade nucleus having “with-the-rule” corneal astigmatism were included in the study. Keratometry measurements were done preoperatively and at 6 weeks post-operative follow-up by Zeiss IOLMaster. Results: Sutureless scleral tunnel based extracapsular cataract extraction was found to neutralize pre-existing corneal astigmatism if it was in range of 1.0–1.5 D. It was also found to change the pattern of astigmatism from “with-the-rule” to “against-the-rule” if the pre-operative astigmatism was in the range of 0.5–1.0 D with little change in the absolute value of the astigmatism. Conclusion: Patients with pre-existing with-the-rule corneal astigmatism undergoing scleral tunnel based sutureless extracapsular cataract extraction had reduced corneal astigmatism. Phacoemulsification, on the other hand, was found to be an astigmatically neutral surgery.

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

10.21203/rs.3.rs-311232/v1 ◽

2021 ◽

Author(s):

Qi Fan ◽

Dongjin Qian ◽

Zhennan Zhao ◽

Yongxiang Jiang ◽

Yi Lu

Keyword(s):

Cataract Surgery ◽

Anterior Segment ◽

Corneal Astigmatism ◽

Corneal Incision ◽

Clear Corneal Incision ◽

Ocular Residual Astigmatism ◽

Age Related ◽

Postoperative Astigmatism ◽

Manifest Refraction ◽

Uncorrected Visual Acuity

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.

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Clinical differences between toric intraocular lens (IOL) and monofocal intraocular lens (IOL) implantation when myopia is determined as target refraction

10.21203/rs.3.rs-54189/v2 ◽

2020 ◽

Author(s):

Da young Shin ◽

Ho Sik Hwang ◽

Hyun Seung Kim ◽

Man Soo Kim ◽

Eun Chul Kim

Keyword(s):

Visual Acuity ◽

Intraocular Lens ◽

Corneal Astigmatism ◽

Spherical Equivalent ◽

Toric Intraocular Lens ◽

Toric Iol ◽

Iol Implantation ◽

Monofocal Iol ◽

Target Refraction ◽

Better Than

Abstract Background: The aim of this study is to analyze and compare the clinical results of toric intraocular lens (IOL) and monofocal IOL implantation when the target refraction value is determined -3 diopter (D) in cataract patients with corneal astigmatism >1.5 diopters (D).Methods: We performed a retrospective chart review for patients with corneal astigmatism >1.5D who underwent cataract surgery and their target refraction is determined -3D. 100 eyes (100 patients; monofocal IOL, 60; toric IOL, 40) were enrolled in the current study. Near and distant uncorrected visual acuity (UCVA), corrected VA, spherical equivalent and refractive, corneal astigmatism were evaluated before and after surgery.Results: The near UCVA of the toric IOL group (0.26±0.33) after cataract surgery was significantly better than that of the monofocal IOL group (0.48±0.32) (p=0.030). The distant UCVA of the toric IOL group (0.38 ± 0.14) was also significantly better than that of the monofocal IOL group (0.55 ± 0.22) (p = 0.026). There were no significant intergroup differences in postoperative best-corrected visual acuity (p = 0.710) and mean spherical equivalent (p = 0.465). In the toric IOL group, postoperative refractive astigmatism was -0.80 ± 0.46D and postoperative corneal astigmatism was -1.50 ± 0.62D, whereas the corresponding values in the monofocal IOL group were -1.65 ± 0.77D and -1.45 ± 0.64D; residual refractive astigmatism was significantly lower with toric IOL implantation compared with monofocal IOL implantation (p = 0.001). There were no postoperative complications and no adverse events were reported.Conclusions: When myopic refraction such as -3D was determined as the target power in patients with corneal astigmatism, toric IOL implantation led to excellent improvement in both near and distant UCVA.

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