Toric intraocular lens implantation versus astigmatic keratotomy to correct astigmatism during phacoemulsification

Femtosecond laser-assisted astigmatic keratotomy versus toric IOL implantation for correcting astigmatism in cataract patients: a systematic review and meta-analysis with trial sequential analysis

AIMS

To compare the refractive and visual outcomes of femtosecond laser-assisted astigmatic keratotomy (FSAK) and toric intraocular lens (IOL) implantation for correcting astigmatism in cataract patients.

METHODS

Studies were retrieved from the Ovid-Medline, EMBASE, Cochrane Central Register of Controlled Trials and Scopus which compared FSAK and toric IOL for astigmatism correction in cataract patients. Outcome measures included postoperative refractive cylinder, correction index, uncorrected distance visual acuity (UDVA), the proportion of patients achieving a residual refractive cylinder of 1.00 dioptre or less, target-induced astigmatism (TIA) and surgically induced astigmatism (SIA). The trial sequential analysis (TSA) was used to collect firm evidence supporting our conclusion.

RESULTS

9 studies encompassing 590 participants were analysed. The meta-analysis revealed that toric IOLs could result in less postoperative refractive cylinder and provide better UDVA compared with FSAK. The TSA disclosed strong evidence of lower postoperative refractive cylinder in the toric IOL group compared with that of the FSAK group. FSAK showed a smaller correction index and lower mean TIA and SIA compared with toric IOLs.

CONCLUSIONS

For cataract patients, both FSAK and toric IOLs are effective methods for correcting astigmatism. However, toric IOLs offer less postoperative astigmatism and result in better postoperative UDVA compared with FSAK. In vector analysis of astigmatism, toric IOLs can also produce higher TIA and SIA. Additionally, neither method is associated with severe untreatable complications. Therefore, the conclusion is that toric IOLs are the preferred choice for astigmatism correction in cataract patients and FSAK serves as a viable alternative when toric IOLs are contraindicated.

Toric Monofocal Intraocular Lenses for the Correction of Astigmatism during Cataract Surgery: A Report by the American Academy of Ophthalmology

PURPOSE

To review the published literature evaluating the visual and refractive outcomes and rotational stability of eyes implanted with toric monofocal intraocular lenses (IOLs) for the correction of keratometric astigmatism during cataract surgery and to compare those outcomes with outcomes of eyes implanted with nontoric monofocal IOLs and other astigmatism management methods performed during cataract surgery. This assessment was restricted to the toric IOLs available in the United States.

METHODS

A literature search of English-language publications in the PubMed database was last conducted in July 2022. The search identified 906 potentially relevant citations, and after review of the abstracts, 63 were selected for full-text review. Twenty-one studies ultimately were determined to be relevant to the assessment criteria and were selected for inclusion. The panel methodologist assigned each a level of evidence rating; 12 studies were rated level I and 9 studies were rated level II.

RESULTS

Eyes implanted with toric IOLs showed excellent postoperative uncorrected distance visual acuity (UCDVA), reduction of postoperative refractive astigmatism, and good rotational stability. Uncorrected distance visual acuity was better and postoperative cylinder was lower with toric IOLs, regardless of manufacturer, when compared with nontoric monofocal IOLs. Correcting pre-existing astigmatism with toric IOLs was more effective and predictable than using corneal relaxing incisions (CRIs), especially in the presence of higher magnitudes of astigmatism.

CONCLUSIONS

Toric monofocal IOLs are effective in neutralizing pre-existing corneal astigmatism at the time of cataract surgery and result in better UCDVA and significant reductions in postoperative refractive astigmatism compared with nontoric monofocal IOLs. Toric IOLs result in better astigmatic correction than CRIs, particularly at high magnitudes of astigmatism.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Attitudes and understanding of premium intraocular lenses in cataract surgery: a public health sector patient survey

OBJECTIVES

To investigate patient understanding of, and attitudes to, premium (toric, extended depth of focus/multifocal) intraocular lenses (premIOLs) in public health sector patients undergoing cataract surgery (CS) in the UK.

METHODS

A 12 question survey with Likert scale questions was designed, to assess patient attitudes to post-operative spectacle dependence, refractive target and desirability of spectacle independence whilst considering possible complications of dysphotopsias and need for premIOL exchange/adjustment.

RESULTS

360 surveys were collected. CS had not been performed in 66.5%. Separate spectacles were worn for reading and distance in 28.8%, 19.2% had varifocals, 11.2% bifocals, 22.9% reading glasses only and 1.6% computer glasses only. Contact lenses were not worn in 95.7%. Only 41.6% were drivers. Most patients (85.8%) did not mind wearing glasses after CS, with 78.9% preferring reading glasses, compared with 29.7% preferring distance glasses. Most patients (75.3%) were not familiar with premIOLs, with 58.9% not willing to consider them in the context of a 2% risk of debilitating dysphotopsia and 54.2% rejecting a 5% risk of second surgery.

CONCLUSIONS

There is a lack of awareness of premIOLs in public health sector (NHS) patients in the UK, suggesting limitations in the "fully informed" consent process for CS. Most NHS CS patients are currently willing to wear spectacles after CS, especially reading glasses. There is reluctance in such patients to consider premIOLs on a background of small risks of debilitating dysphotopsias and increased risks of a second operation.

Toric Intraocular Lens versus Peripheral Corneal Relaxing Incisions for Astigmatism between 0.75 and 2.5 Diopters: 5-Years Outcomes

PURPOSE

To compare 5-year outcomes of toric intraocular lens (tIOL) or peripheral corneal relaxing incision (PCRI) for correction of keratometric astigmatism (KA) between 0.75 and 2.5 diopters (D).

METHODS

Setting: University Hospital. Design: Randomized clinical trial. Eighty eyes (80 participants) received either tIOL or PCRI. Patients were assessed preoperatively, 1-month, 1, and 5 years. Primary outcomes were uncorrected (UDVA) and best-corrected distance logMAR visual acuity (CDVA). Secondary outcomes were a manifest refractive sphere, refractive astigmatism (Ra), spherical equivalent (SEQ), KA & mean keratometry (KM), and Quality-of-Life Impact of Refractive Correction (QIRC) scores.

RESULTS

There was no difference between the two groups in UDVA, CDVA, refractive sphere, KM, RA, and SEQ. KA reduced after 1 month in the PCRI group and remained stable until 5 years. From 1 to 5 years, the number of eyes with distance emmetropia (within ±0.13D) changed from 59% (20/34 eyes) to 32% (6/19 eyes) for tIOLs and from 43% (15/36 eyes) to 20% (4/21 eyes) for PCRIs with 32% (6/19 eyes) and 20% (4/21 eyes) showing >0.5D change in SEQ at 5-years respectively. Compared to 1-year, Ra significantly increased at 5 years in both groups with no difference between the groups. Mean overall QIRC scores were not different between the groups (tIOL: 49.88 ± 7.47; PCRI: 52.09 ± 7.02; p = .18).

CONCLUSIONS

Although there was no difference between the overall visual and vision-related quality of life outcomes between tIOLs and PCRIs, an increase in refractive astigmatism and reduction in distance emmetropia with time was noted in both groups.

The Efficacy of Paired Opposite Clear Corneal Incisions Correcting Preexisting Low-to-Moderate Astigmatism in Implantable Collamer Lens Surgery

PURPOSE

To evaluate the efficacy of paired opposite clear corneal incisions (OCCIs) in Implantable Collamer Lens (ICL; STAAR Surgical) implantation surgery for correcting preexisting low-to-moderate astigmatism and observe their influence on corneal aberration.

METHODS

This prospective controlled randomized study included 123 eyes: 73 eyes in the ICL surgery group (control group) and 50 eyes in the ICL combined with OCCI group (OCCI group). All patients had corneal astigmatism between 0.50 and 3.00 D. Parameters considered included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refraction, keratometry, slit-lamp biomicroscopy, indirect ophthalmoscopy, corneal topography, and higher order aberrations (HOAs). The Alpins method was used to analyze the correction of astigmatism. The follow-up period lasted for 12 months.

RESULTS

Both groups showed a statistically significant improvement in mean UDVA and CDVA after surgery. At 1 and 12 months, the OCCI group had statistically better UDVA than the control group (P = .021 and .01). The OCCI group showed a significant reduction in mean refractive astigmatism from -0.835 ± 0.274 to -0.535 ± 0.353 and -0.450 ± 0.346 D postoperatively (P < .05) after 1 and 12 months. No significant change was observed in the control group (P > .05). The average magnitude of surgically induced astigmatism (SIA) was 0.911 ± 0.442 and 0.811 ± 0.397 D at 1 and 12 months postoperatively, respectively, in the OCCI group, which was slightly lower than the target induced astigmatism. The difference in SIA between the OCCI and control groups was significant by the end of 1 and 12 months postoperatively (P < .0001). The mean correction index was below 1, suggesting an undercorrection effect caused by clear corneal incisions in the opposite direction. HOAs increased in both the control and OCCI groups after surgery (t = 5.668, P < .0001, t = 3.773, P = .0003, respectively), with oblique trefoil only significantly increasing in the OCCI group.

CONCLUSIONS

This study demonstrated that OCCIs represent a secure, efficient, reliable, and long-term technique for reducing preexisting low-to-moderate corneal astigmatism during ICL surgery. However, OCCIs did not show any advantageous impact in terms of wavefront aberrations when compared to the traditional single-incision method. The presence of oblique trefoil may be the main contributor to the alteration of HOAs during OCCI surgery. [J Refract Surg. 2024;40(1):e20-e29.].

Effect of femtosecond laser-assisted arcuate keratotomy versus toric intraocular lens implantation on correction of astigmatism in cataract surgery: a systematic review and meta-analysis

PURPOSE

To compare the efficacy of femtosecond laser-assisted arcuate keratotomy (FSAK) combined with non-toric intraocular lens (IOL) implantation versus Toric IOL (TIOL) implantation in correcting corneal astigmatism in cataract patients.

METHODS

Relevant literature was searched in databases including PubMed, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), and SinoMed. Data from the included studies were extracted. A meta-analysis was conducted to compare the correction performance of FSAK combined with non-toric IOL implantation and TIOL implantation using postoperative refractive astigmatism, correction index, and uncorrected distance visual acuity (UDVA) outcomes. Publication bias assessment and sensitivity analysis were also performed.

RESULTS

Five comparative studies were ultimately included in the meta-analysis. The TIOL group had smaller postoperative refractive astigmatism and a greater correction index compared to the FSAK group. The mean differences in postoperative refractive astigmatism and correction index between the two groups were - 0.19D (95% CI = 0.12 to 0.26, P < 0.01, I2 = 7%) and - 0.09 (95% CI =  - 0.18 to 0.00, P = 0.04, I2 = 0%), respectively. We found no statistically significant difference in UDVA between the two groups (95% CI =  - 0.01 to 0.11, P = 0.09, I2 = 70%).

CONCLUSIONS

FSAK combined with non-toric IOL implantation was found to be less effective than TIOL implantation in correcting preoperative corneal astigmatism in cataract patients. The difference in the effectiveness of astigmatism correction between the two surgical methods seems to diminish, as the degree of preoperative corneal astigmatism decreases.

Cataract surgery astigmatism incisional management. Manual relaxing incision versus femtosecond laser-assisted arcuate keratotomy. A systematic review

PURPOSE

This systematic review aims to compare corneal astigmatism correction in cataract surgery through corneal relaxing incision, manually and femtosecond laser assisted.

METHODS

The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement recommendations. We used PubMed, Scopus, and Web of Science (WOS) as databases from January 2010 to March 30, 2021. Patients with keratoconus, corneal ectasia, and a previous history of eye surgery were excluded because our aim was to analyze only healthy eyes.

RESULTS

A total of 1025 eyes were evaluated from 946 patients (mean age was 68.90 ± 5.12) in manual incision group articles, while 1905 eyes of 1483 patients (mean age was 65.05 ± 4.57) were evaluated in femtosecond laser arcuate keratotomy (FLAK) articles. The mean uncorrected distance visual acuity (UDVA) was 0.19 ± 0.12 and 0.15 ± 0.05 logMAR for manual incision and FLAK articles, respectively (p = 0.39). The mean correction index (CI) was similar in both groups: 0.77 ± 0.18 in manual incision and 0.79 ± 0.17 in femtosecond laser assisted incision (p = 0.70). Refractive stability was found after 3 months and no serious complications were reported during the follow-up in any group.

CONCLUSION

Both techniques are safe and moderately effective in corneal astigmatism correction in cataract surgery. FLAK represents a more precise and predictable approach. However, since visual and refractive outcomes appear to be similar in both cases, the cost-benefit analysis is controversial.

Correction of pre-existing astigmatism with phacoemulsification using toric intraocular lens versus spherical intraocular lens and wave front guided surface ablation

Background

This study aimed to evaluate toric intraocular lens to correct of pre-existing astigmatism at the time of phacoemulsification compared to using of spherical intraocular lens followed by wavefront guided surface ablation.

Results

The patients were classified into three groups: Group A with 20 eyes of 19 patients having phacoemulsification with spherical intraocular lens only as a control group, group B with 20 eyes of 14 patients had phacoemulsification with toric intraocular lens and group C with 20 eyes of 16 patients had phacoemulsification with spherical intraocular lens and wavefront guided PRK three months later. Comparison pre-operative data for all groups showed no statistically significant difference regarding UCVA, BCVA, MRSE, and refractive astigmatism (P>0.05). Post operatively, there was a statistically significant difference for UCVA, BCVA, MRSE, and refractive astigmatism for group A compared to group B (P<0.05) and group A compared to group C but there was no statistically significant difference for group B compared to C regarding all these parameters (P>0.05).

Conclusion

In this study, we found similar effects for both techniques in astigmatism corrected groups while both differed from the control group that was not corrected. Correcting preexisting astigmatism during cataract surgery should be in mind in every case to improve visual outcomes. Longer period of follow up are required to evaluate stability of these techniques and possibility of regression.

Do limbal relaxing incisions during cataract surgery still have a role?

BACKGROUND

Though Limbal Relaxing Incisions (LRI) were used widely to correct pre-existing corneal astigmatism during cataract surgery, they have been replaced recently with the more expensive methods like the use of toric Intra Ocular Lenses (IOL) and femtosecond during cataract surgery. We conducted our study to re-evaluate the role of (LRI) in correcting pre-existing moderate corneal astigmatism during cataract surgery in settings where other options are neither available nor affordable.

METHODS

Retrospective analysis of all consecutive cases of LRI performed by a single surgeon at the time of cataract surgery to correct moderate corneal astigmatism (1.5-3D) in a community hospital over a period of 6 months. Corneal astigmatism, uncorrected distance visual acuity (UDVA) and best corrected distance visual acuity (CDVA) were recorded pre-operatively, 4 weeks and 3 months post-operatively. Data on age, intraocular lens (IOL) power, predictive refraction and post-operative spherical equivalent was also collected and analyzed. The number and position of LRI was determined based on the pre-existing corneal astigmatism using online calculator.

RESULTS

29 eyes of 25 patients with the mean age of 73.6 years (range: 46 to 90 years) and corneal astigmatism between 1.5 to 3D were included. Statistically significant reduction in the mean corneal astigmatism was recorded from 2.05 ± 0.45D preoperatively to 0.85 ± 0.56D postoperatively (P < 0.0001). All eyes showed reduction in astigmatism; 83% of eyes had < 1.0D post-operatively and 66% of eyes had < 0.75D. UDVA of 6/9 or better was recorded in 80% of eyes post-operatively (CDVA of 6/9 or better in 100%). The spherical equivalent was within 1.0D of the predictive refraction postoperatively in nearly all eyes (97%) and within 0.5D in 86% of the eyes. There were no peri-operative or post-operative complications were recorded in any case.

CONCLUSION

Combining LRI and cataract surgery to address moderate degrees of corneal astigmatism is a safe, reliable and predictable option especially in areas where more expensive methods such as toric IOL or excimer laser are not available or affordable. LRI has no significant effect on the spherical equivalent and is an excellent tool in reducing patient's spectacle dependence.

Toric intraocular lens implantation vs. femtosecond laser-assisted arcuate keratotomy for correction of moderate astigmatism in cataract surgery

PURPOSE

To compare toric intraocular lens (TIOL) implantation and femtosecond laser-assisted arcuate keratotomy (FSAK) during phacoemulsification surgery in correction of moderate astigmatism.

SETTING

Clinical research study.

DESIGN

Prospective randomized comparison study.

METHODS

Patients with age-related cataract and moderate preoperative corneal astigmatism of 1.25 to 3.0 diopters (D) were randomized into a TIOL implant group and an FSAK group with symmetrical paired corneal arcuate keratotomies. The preoperative evaluation included corrected distance visual acuity (CDVA), corneal topography, autokeratometry and ocular biometry. Postoperative examinations were performed at 1 and 3 months and included CDVA and uncorrected distance visual acuity (UDVA), manifest refraction, autokeratometry and corneal topography. Vector analysis of astigmatic changes was performed using the Alpins vector method.

RESULTS

This study comprised 75 eyes from 67 patients. Mean residual refractive astigmatism at 3 months was -0.63 ± 0.55 D in the TIOL group and -0.90 ± 0.53 D in the FSAK group (P = 0.037) and was ≤ 1.00 D in 32 eyes (84%) and 25 eyes (64%), respectively. There were no statistically significant differences in difference vector (DV), angle error (AE), magnitude error (ME) or correction index (CI) in the 3-month follow-up. The index of success (IS) was 0.32 ± 0.33 D in the TIOL group and 0.48 ± 0.29 D in the FSAK group (P = 0.029).

CONCLUSION

TIOL implantation showed better results in correcting moderate astigmatism. Despite this, FSAK is shown to be a safe technique for reducing astigmatism.

Accuracy and safety of partial thickness femtosecond laser radial and arcuate keratotomy incisions in porcine eyes

Background

To evaluate the accuracy and safety of micro radial and arcuate keratotomy incisions constructed by a femtosecond laser system with a curved contact patient interface in porcine eyes.

Methods

Partial thickness micro radial and arcuate keratotomy incisions were constructed in porcine eyes with a femtosecond laser system and evaluated for precision of depth, quality, and consistency. Optical coherence tomography was used to determine the accuracy and precision of incision depth. Corneal endothelial safety was assessed by a fluorescent live/dead cell viability assay to demonstrate laser-induced endothelial cell loss. Quality was evaluated by ease of opening and examination of interfaces.

Results

In two micro radial incision groups, intended incision depths of 50% and 80% resulted in mean achieved depths of 50.01% and 77.69%, respectively. In three arcuate incision groups, intended incision depths of 80%, 600 μm or 100 μm residual uncut bed thickness resulted in mean achieved depths of 80.16%, 603.03 μm and residual bed of 115 μm, respectively. No loss of endothelial cell density occurred when the residual corneal bed was maintained at a minimum of 85–116 µm. The incisions were easy to open, and interfaces were smooth.

Conclusions

A femtosecond laser system with curved contact interface created precise and reproducible micro radial and arcuate keratotomy incisions. Accuracy and precision of the incision depth and preservation of endothelial cell density demonstrated the effectiveness and safety of the system.

Refractive outcomes of femtosecond laser-assisted cataract surgery with arcuate keratotomy and standard phacoemulsification with toric intraocular lens implantation

PURPOSE

Femtosecond laser arcuate keratotomy (FS-AK) and toric intraocular lens (IOL) implantation are effective for the correction of eyes with corneal astigmatism. In this study, the postoperative refractive outcomes of patients receiving femtosecond laser-assisted cataract surgery (FLACS) with FS-AK and patients receiving standard phacoemulsification with toric IOL implantation were evaluated.

METHODS

This retrospective study reviewed the postoperative outcomes of patients undergoing FLACS with FS-AK (the FS-AK group) and patients undergoing standard phacoemulsification with toric IOL implantation (the toric IOL group). The main outcome measures were uncorrected and corrected visual acuities, keratometric and refractive astigmatism, and vector analysis.

RESULTS

The FS-AK group included 41 eyes with preoperative keratometric astigmatism of - 1.64 ± 0.42 diopters (D), and the toric IOL group included 53 eyes with preoperative keratometric astigmatism of - 2.29 ± 0.91 D (P < 0.001). Postoperative refractive astigmatism was comparable between the two groups. Compared with the FS-AK group, postoperative uncorrected visual acuity was significantly better (P = 0.005) and corrected visual acuity was marginally better in the toric IOL group (P = 0.051). The absolute angles of error were 9.95° ± 9.57° and 5.08° ± 4.94° (P = 0.02) in the FS-AK and the toric IOL groups, respectively.

CONCLUSION

Both FLACS with FS-AK and standard phacoemulsification with toric IOL implantation are safe and effective methods for astigmatism correction during cataract surgery. Standard phacoemulsification with toric IOL implantation achieves better visual acuity than FLACS with FS-AK at the 6-month follow-up.

Comparison of penetrating femtosecond laser-assisted astigmatic keratotomy and toric intraocular lens implantation for correction of astigmatism in cataract surgery

This study tried to compare the clinical outcomes of femtosecond laser-assisted astigmatic keratotomy (FSAK) and toric intraocular lens (IOL) implantation for astigmatism correction and identify factors affecting the efficacy of FSAK and toric IOL implantation in astigmatism correction. This retrospective case series comprised patients with corneal astigmatism ranging between 0.5 D and 4.5 D. Patients underwent FSAK or toric IOL implantation for cataract treatment and correction of astigmatism at the Samsung Medical Center, a tertiary surgical center, between April 2016 and December 2018. All patients underwent examination before and at three months after the surgery for comparative evaluation of refractive astigmatism, corneal high order aberrations and irregularity index. The astigmatism correction was analyzed by the Alpins method. Subgroup analysis of preoperative factors was based on the extent of target-induced astigmatism (TIA), the degree of astigmatism, and astigmatism classification based on topography. Thirty-one eyes underwent toric IOL implantation and 35 eyes underwent FSAK. The refractive astigmatism was significantly decreased in both toric IOL (P = 0.000) and FSAK group (P = 0.003). The correction index (CI) of refractive astigmatism was 0.84 ± 0.39 in the toric IOL and 0.71 ± 0.60 in the FSAK group. There was no difference between the two groups (P = 0.337). The CI of the FSAK group was significantly lower than in the toric IOL group when TIA was more than 1.5 D (P = 0.006), when correcting against-the-rule (P = 0.017), and limbus-to-limbus astigmatism (P = 0.008). In conclusion, toric IOL implantation is an effective and safe procedure for correcting preoperative astigmatism in cataract surgery in the short-term observation.

Evaluation of Astigmatic Correction Using Vector Analysis after Combined Femtosecond Laser-Assisted Phacoemulsification and Intrastromal Arcuate Keratotomy

The aim of this study was to evaluate astigmatic correction in patients with mild to moderate astigmatism after combined femtosecond laser-assisted cataract surgery (FLACS) and intrastromal arcuate keratotomy (ISAK), using vector analysis. This retrospective study included patients with corneal astigmatism of 0.5–3.0 diopters (D) who underwent FLACS and ISAK. Vector analyses of astigmatism were performed using the Alpins method, considering three vectors: target-induced astigmatism (TIA), surgically induced astigmatism (SIA), and difference vector (DV). Magnitude of error (ME), angle of error (AE), correction index (CI), and coefficient of adjustment (CA) were calculated. Subgroup analysis according to the axis of astigmatism, patient age, and white to white (WTW) diameter was conducted. In total, for the 79 eyes of 79 patients, the TIA was 1.21 ± 0.52 D, the SIA was 0.76 ± 0.53 D, and the DV was 0.86 ± 0.50 D. The ME (difference between SIA and TIA) was −0.46 ± 0.45 D, and the CI (ratio of SIA and TIA) was 0.62 ± 0.34; both these parameters demonstrated slight undercorrection. The CA (inverse of the CI) was 2.48 ± 2.61. The AE was 4.02° ± 28.7°, and the absolute AE was 21.7° ± 19.0°. In the univariate regression analyses to identify factors that affected the CI, there was a negative correlation between age and the CI (P=0.022). In conclusion, vector analysis after the combined FLACS and ISAK revealed slight undercorrection, regardless of the astigmatism meridian. The precision of the nomogram should be improved through long-term vector analysis for the results of arcuate keratotomy and through further research on the relationship between patient demographics and CI. Overall, this study has shown that FLACS and ISAK could reduce postoperative corneal astigmatism effectively and safely.

Comparing Visual Acuity, Low Contrast Acuity and Refractive Error After Implantation of a Low Cylinder Power Toric Intraocular Lens or a Non-Toric Intraocular Lens

Purpose

To compare uncorrected and best-corrected visual acuity, low contrast acuity, residual refraction and ocular biometry after low cylinder power toric intraocular lens (IOL) or non-toric IOL implantation.

Patients and Methods

This was a non-interventional comparative study of visual outcomes after uncomplicated cataract or refractive lens exchange surgery with either a low cylinder (Low_Cyl) or non-toric (Non_Toric) IOL of similar design implanted (AcrySof^® T2 IQ Toric IOL and AcrySof^® IQ IOL). Subjects in both groups had to have been eligible for the low cylinder IOL based on biometry. They had to have uncorrected distance visual acuity (UDVA) of 20/32 (0.2 logMAR) or better at the time of their single diagnostic study visit. Clinical evaluation included the manifest refraction, visual acuity (VA), low contrast VA and ocular biometry.

Results

A total of 94 eyes were enrolled, 51 Low_Cyl and 43 Non_Toric. The mean manifest refractive cylinder was statistically significantly lower (~0.25 D) in the Low_Toric group (p < 0.01) and significantly more eyes had 0.25 D or less of refractive cylinder in that group (p = 0.03). The orientation of the preoperative anterior corneal astigmatism was a significant cofactor, with the difference between groups more evident when astigmatism was against the rule. Uncorrected high contrast visual acuity was statistically significantly better in the Low_Toric group (p = 0.02) as was the percentage of eyes with 20/20 visual acuity (p = 0.05). Uncorrected low contrast visual acuity was not statistically significantly different in mesopic or photopic conditions.

Conclusion

The low cylinder power toric IOL provided better uncorrected visual acuity and lower residual refractive cylinder than a similar non-toric IOL after cataract surgery.

A randomised, prospective study of 'off-the-shelf' use of toric intraocular lenses for cataract patients with pre-existing corneal astigmatism in the NHS

BACKGROUND/OBJECTIVES

To compare visual and refractive outcomes of monofocal intraocular lenses (IOLs) with limbal relaxing incisions (LRI) with 'off-the-shelf' use of toric IOLs (TIOLs), with a fixed 2-dioptre cylinder (DC) correction, for cataract patients with pre-existing corneal astigmatism in a public-sector setting.

SUBJECTS/METHODS

Seventy-seven patients (77 eyes, first treated eye) with visually significant cataract and pre-operative corneal astigmatism ≥2.00 DC were randomised to receive either 'off-the-shelf' TIOLs, with a fixed 2.00 DC cylinder correction (39 eyes), or monofocal IOLs (38 eyes) with LRIs. The concept of fixing the cylindrical correction was to minimise costs, allow a full TIOL bank to be available and eliminate the need for individual TIOL ordering. Outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA) and refraction. Astigmatic changes were evaluated using the Alpins vector method.

RESULTS

Mean UDVA improved from logMAR 0.88 (SD 0.56)[~20/150] pre-operatively to 0.18 (SD 0.19)[~20/30] post-operatively in TIOL group, versus 0.82 (SD 0.55)[~20/130] to 0.27 (SD 0.15)[~20/40] in monofocal/LRI group (P = 0.02; 95% CI: -0.17, -0.01). Mean CDVA improved from logMAR 0.40 (SD 0.26)[~20/50] to 0.01 (SD 0.12)[~20/20] in TIOL group, and 0.41 (SD 0.38)[~20/40] to 0.06 (SD 0.12)[~20/25] in LRI group (P = 0.07; 95% CI: -0.11, 0.01). Average post-operative refractive cylinder in TIOL group was 1.35 DC (SD 0.84 DC) and in LRI group 1.91 DC (SD 1.07 DC) (P = 0.01; 95% CI: -1, -0.12). Mean difference vector magnitude was 1.92 DC (SD 1.08 DC) in LRI group and 1.37 DC (SD 0.84 DC) in TIOL group (P = 0.02; 95% CI: 0.11, 0.99).

CONCLUSIONS

TIOLs with a fixed 2.00 DC correction during cataract surgery may improve UDVA, reduce post-operative cylinder and result in a more reliable astigmatic correction compared with monofocal IOLs with LRIs.

Femtosecond laser-assisted cataract surgery: A review

PURPOSE

Review scientific literature concerning femtosecond laser-assisted cataract surgery.

METHODS

Following databases were searched: CENTRAL (Cochrane Eyes and Vision Trials Register; Cochrane Library: Issue 2 of 12, June 2019), Ovid MEDLINE^® without Revisions (1996 to June 2019), Ovid MEDLINE^® (1946 to June 2019), Ovid MEDLINE^® Daily Update June 2019, MEDLINE and MEDLINE Non-Indexed Items, Embase (1980-2019), Embase (1974 to June 2019), Ovid MEDLINE^® and Epub Ahead of Print, in-Process & Other Non-Indexed Citations and Daily (1946 to June 2019), Web of Science (all years), the metaRegister of Controlled Trials ( www.controlled-trials.com ), ClinicalTrials.gov ( www.clinicaltrial.gov ) and World Health Organization International Clinical Trials Registry Platform ( www.who.int/ictrp/search/en ). Search terms/keywords included 'Femtosecond laser' combined with 'cataract', 'cataract surgery'.

RESULTS

Based on quality of their methodology and their originality, 121 articles were reviewed, including randomised controlled trials, cohort studies, case-controlled studies, case series, case reports and laboratory studies. Each step of the femtosecond laser-assisted cataract surgery procedure (corneal incisions, arcuate keratotomies, capsulotomy and lens fragmentation) has been discussed with relevance to published outcomes, as well as complication rates of femtosecond laser-assisted cataract surgery, and what we can learn from the larger studies/meta-analyses and the economics of femtosecond laser-assisted cataract surgery within different healthcare settings.

CONCLUSION

Studies suggest that the current clinical outcomes of femtosecond laser-assisted cataract surgery are not different to conventional phacoemulsification surgery and it is not cost effective when compared with conventional phacoemulsification surgery. In its current technological form, it is a useful surgical tool in specific complex cataract scenarios, but its usage has not been shown to translate into better clinical outcomes.

Outcome of toric intraocular lenses implanted in eyes with previous corneal refractive surgery

PURPOSE

To evaluate the outcome of toric intraocular lens (IOL) implantation in eyes with previous laser in situ keratomileusis/photorefractive keratectomy (LASIK/PRK).

SETTING

Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA.

DESIGN

Retrospective case series.

METHODS

Consecutive cases that had previous myopic or hyperopic LASIK/PRK and had undergone cataract surgery with toric IOL implantation were retrospectively reviewed. Included were eyes that had (1) preoperative ocular biometry measurements with the Lenstar, (2) no intraoperative or postoperative complications, and (3) available postoperative manifest refraction at ≥3 weeks with corrected distance visual acuity of 20/30 or better. Vector analysis was used to assess the preoperative corneal and postoperative refractive astigmatism.

RESULTS

In 56 eyes with previous myopic LASIK/PRK and 19 eyes with previous hyperopic LASIK/PRK, respectively, the mean magnitudes of corneal astigmatism were 1.34 ± 0.62 diopters (D) and 1.66 ± 0.80 D, 5% and 0% of eyes had anterior corneal astigmatism ≤0.50 D, and the centroid values were 0.31 D at 19 degrees ± 1.45 D and 0.74 D at 92 degrees ± 1.72 D preoperatively. Postoperatively, the mean magnitudes of refractive astigmatism were 0.36 ± 0.31 D and 0.34 ± 0.34 D, 80% and 84% of eyes had refractive astigmatism of ≤0.50 D, and the centroid values were 0.12 D at 152 degrees ± 0.46 D and 0.05 D at 172 degrees ± 0.48 D (all P < .05).

CONCLUSIONS

Toric IOLs were effective to correct preexisting corneal astigmatism in eyes with previous excimer laser corneal refractive surgery.

Toric intraocular lens versus limbal relaxing incisions for corneal astigmatism after phacoemulsification

BACKGROUND

Cataract is the leading cause of blindness in the world, and clinically significant astigmatism may affect up to approximately 20% of people undergoing cataract surgery. Pre-existing astigmatism in people undergoing cataract surgery may be treated, among other techniques, by placing corneal incisions near the limbus (limbal relaxing incisions or LRIs) or by toric intraocular lens (IOLs) specially designed to reduce or treat the effect of corneal astigmatism on unaided visual acuity.

OBJECTIVES

To assess the effects of toric IOLs compared with LRIs in the management of astigmatism during phacoemulsification cataract surgery.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register; 2019, Issue 9); Ovid MEDLINE; Ovid Embase and four other databases. The date of the search was 27 September 2019.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing toric IOLs with LRIs during phacoemulsification cataract surgery.  DATA COLLECTION AND ANALYSIS: We used standard methods expected by Cochrane. We graded the certainty of the evidence using GRADE. Our primary outcome was the proportion of participants with postoperative residual refractive astigmatism of less than 0.50 dioptres (D) six months or more after surgery. We also collected data on mean residual refractive astigmatism. Secondary outcomes included: uncorrected distance visual acuity, vision-related quality of life, spectacle independence and adverse effects including postoperative lens rotation requiring re-alignment. To supplement the main systematic review assessing the effects of toric IOLs compared with LRIs in the management of astigmatism during phacoemulsification cataract surgery, we sought to identify economic evaluations on the subject.

MAIN RESULTS

We identified 10 relevant studies including 517 people (626 eyes). These studies took place in China (three studies), UK (three), Brazil (one), India (one), Italy (one) and Spain (one). The median age of participants was 71 years. The level of corneal astigmatism specified in the inclusion criteria of these studies ranged from 0.75 D to 3 D. A variety of toric IOLs were used in these studies, in all but one study, these were monofocal. Studies used three different nomograms to determine the size and placement of the LRI. Two studies did not specify this. None of the studies were at low risk of bias in all domains, but two studies were at low risk of bias in all domains except selective outcome reporting, which was unclear. The remaining studies were at a mixture of low, unclear or high risk of bias. People receiving toric IOLs were probably more likely to achieve a postoperative residual refractive astigmatism of less than 0.5 D six months or more after surgery (risk ratio (RR) 1.40, 95% confidence interval (CI) 1.10 to 1.78; 5 RCTs, 262 eyes). We judged this to be moderate-certainty evidence, downgrading for risk of bias. In the included studies, approximately 500 eyes per 1000 achieved postoperative astigmatism less than 0.5 D in the LRI group compared with 700 per 1000 in the toric IOLs group. There was a small difference in residual astigmatism between the two groups, favouring toric IOLs (mean difference (MD) -0.32 D, 95% CI -0.48 to -0.15 D; 10 RCTs, 620 eyes). Although all studies favoured toric IOLs, the results of individual studies were inconsistent (range of effects -0.02 D to -0.71 D; I² = 89%). We considered this to be low-certainty evidence, downgrading for risk of bias and inconsistency. People receiving a toric IOL probably have a small improvement in visual acuity at six months or more after surgery compared to people receiving LRI, but the difference is small and probably clinically insignificant (MD -0.04 logMAR, 95% CI -0.07 to -0.02; 8 RCTs, 474 eyes; moderate-certainty evidence). Low-certainty evidence from one study of 40 people suggested little difference in vision-related quality of life measured using the Visual Function Index (VF-14) (MD -3.01, 95% CI -8.56 to 2.54). Two studies reported spectacle independence and suggested that people receiving toric IOLs may be more likely to be spectacle independent (RR 1.56, 95% CI 1.14 to 2.15; 100 people; low-certainty evidence). There were no cases of lens rotation requiring surgery (very low-certainty evidence). Five studies (320 eyes) commented on a range of other adverse effects including corneal oedema, endophthalmitis and corneal ectasia. All these studies reported that there were no adverse events with the exception of one study (40 eyes) where one participant in the LRI group had a central de-epithelisation which recovered over 10 days. We found no economic studies that compared toric IOLs with LRIs.

AUTHORS' CONCLUSIONS

Toric IOLs probably provide a higher chance of achieving astigmatism within 0.5 D after cataract surgery compared with LRIs. There may be a small mean difference in postoperative astigmatism, favouring toric IOLs, but this difference is likely to be clinically unimportant. There was no evidence of an important difference in postoperative visual acuity or quality of life between the techniques. Evidence on adverse effects was uncertain. The apparent shortage of relevant economic evaluations indicates that economic evidence regarding the costs and consequence of these two procedures is currently lacking.

Utilizing intraoperative aberrometry and digital eye tracking to develop a novel nomogram for manual astigmatic keratotomy to effectively decrease mild astigmatism during cataract surgery

PURPOSE:

The purpose of the study is to develop a novel nomogram and validate with a retrospective comparative study for manual astigmatic keratotomy (MAK) with the assistance of intraoperative aberrometry (Optiwave Refractive Analysis [ORA]) and digital eye tracking (VERION) in mild astigmatic correction enhancement.

SETTING:

The study was conducted in Honolulu, Hawaii.

DESIGN:

This was a single-surgeon comparative study with retrospective data collection.

METHODS:

Sixty consecutive adult cataract surgery cases with regular astigmatism of 1.25 D or less were included for study from April 2016 to April 2017. VERION was used preoperatively in all cases. MAK was performed before phacoemulsification according to the surgeon's own nomogram. ORA then was utilized to obtain the axis and remaining cylinder power after phacoemulsification and intraocular lens implant implantation. MAK extension was performed for eyes with 1 D or more of remaining cylinder. Extensions were carried out slowly and slightly until the amount of cylinder was 1½ D or less under ORA. The mean degrees of extension plus the original MAK plan were calculated to develop the new nomogram. Sixty consecutive similar cases by the same surgeon using the surgeon's nomogram without using ORA/VERION for enhancement were reviewed from April 2015 to April 2016 for comparison. All patients included in this study signed the consent form.

RESULTS:

Using Alpins vector analysis for comparison, the proportion of patients with cylinder <0.5 D 3 months postoperatively was 87% in the ORA/VERION group compared to 70% in the non-ORA/VERION group (P < 0.05). Better than 20/25 best-corrected visual acuity was achieved more in the ORA/VERION group compared to non-ORA/VERION group.

CONCLUSIONS:

This novel nomogram developed by the surgeon may have better outcomes than the old surgeon's own nomogram. Further prospective control study is needed to validate the efficacy. If validated, those surgeons who do not have ORA/VERION can hopefully use this nomogram with greater success.

Phacoemulsification With 3.0 and 2.0 mm Opposite Clear Corneal Incisions for Correction of Corneal Astigmatism

PURPOSE

To compare the effect of 3.0 and 2.0 mm opposite clear corneal incisions (OCCIs) in phacoemulsification on reduction of preexisting corneal astigmatism, and their impact on corneal aberrations.

METHODS

This study is a prospective randomized controlled study that included 140 patients with age-related cataract and regular corneal astigmatism ≥0.75 diopter (D). Phacoemulsification was performed using on-meridian 3.0 or 2.0 mm corneal incision with or without an OCCI. Cases were divided into 4 groups: 3.0 mm OCCIs, 3.0 mm single clear corneal incision (3.0 mm SCCI), 2.0 mm OCCIs, and 2.0 mm SCCI. Keratometry and topography were performed at 3 months postoperatively. The variations in corneal astigmatism and aberrations were recorded. Surgically induced astigmatism was calculated using vector analysis.

RESULTS

The corneal astigmatism reduction was 0.61 ± 0.38 D in the 3.0 mm OCCIs group, significantly higher than the other groups (P ≤ 0.004); and 0.29 ± 0.29 D in the 2.0 mm OCCIs group. The mean surgically induced astigmatism was 1.07 ± 0.51 D in the 3.0 mm OCCIs group, higher than 0.61 ± 0.35 D in the 2.0 mm OCCIs group (P = 0.001). The root mean square values of corneal trefoil, spherical aberration, and total higher order aberrations increased at 3 months postoperatively, but there were no significant differences between OCCI and SCCI groups.

CONCLUSIONS

On-meridian 3.0 mm OCCIs are effective for correcting mild-to-moderate corneal astigmatism during cataract surgery, exerting no additional impact on corneal aberration compared with SCCI.

Comparison of visual performance of toric vs non-toric intraocular lenses with same material

Aim

We compared the visual performance of toric intraocular lenses (IOLs) and non-toric IOLs made of the same material.

Patients and materials:

The subjects included patients implanted with either Acrysof IQ^® toric IOLs (SN6AT3-9) or Acrysof IQ^® IOLs (SN60WF) bilaterally. The toric group included 103 patients who were implanted with Acrysof IQ toric IOLs bilaterally. The non-toric group was a corneal astigmatism-matched control group and included 103 patients who were implanted with Acrysof IQ IOLs bilaterally.

Results

The uncorrected distance visual acuity was significantly better in the toric group, whereas the uncorrected 50 cm visual acuity was better in the non-toric group. There was no significant difference in contrast sensitivity (with and without glare) between both the groups. The rate of spectacle dependency for distance vision was significantly lower in the toric group. There were no significant differences between the two groups in all items of the postoperative quality-of-vision questionnaire (25-item Visual Function Questionnaire).

Conclusion

The toric IOLs used in this study reduced spectacle dependency more than the non-toric IOLs and did not compromise the subjective visual function, but the uncorrected 50 cm vision was worse in toric IOL implanted eyes.

Improving the Toric Intraocular Lens Calculation by Considering Posterior Corneal Astigmatism and Surgically-induced Corneal Astigmatism

PURPOSE

To investigate the effect of surgically induced corneal astigmatism (SICA) and total corneal astigmatism (TCA) estimation on the anterior corneal astigmatism (ACA)-based toric intraocular lens (IOL) calculation.

METHODS

Data from preoperative and postoperative corneal astigmatism, postoperative visual acuities, and refractive outcomes were collected. The incision was superior in with the rule anterior corneal astigmatism (WTRA) eyes and temporal in against the rule anterior corneal astigmatism eyes. The following five methods of calculating the toric IOL were compared: (1) ACA only and estimated SICA; (2) ACA with a fixed posterior corneal astigmatism (PCA) and estimated SICA; (3) ACA with a fixed PCA value and actual SICA; (4) and (5) TCA derived from the regression equations of ACA and actual SICA. The residual astigmatism was simulated. The Alpins method was used to analyze the astigmatism.

RESULTS

Sixty eyes from 46 patients were enrolled. Thirty eyes had WTRA and the other thirty had against the rule anterior corneal astigmatism. The vector and arithmetic means of the difference vector decreased when the information regarding the actual SICA and PCA was added to the calculation (from 0.59 diopters [D] @ 87.5° to 0.15 D @ 48.5°, and from 0.95 ± 0.53 to 0.71 ± 0.63 D, respectively; p < 0.001). The mean difference vector across the whole sample was lowest using model 5. The correction index was significantly closest to 1.0 in the WTRA group.

CONCLUSIONS

Researchers may improve the accuracy of post-implantation predictions by calculating toric IOL using exact SICA and TCA, with consideration of the PCA derived from the regression equation of ACA.

Evaluation of the effectiveness of combined femtosecond laser-assisted cataract surgery and femtosecond laser astigmatic keratotomy in improving post-operative visual outcomes

Background

To determine postoperative refractive and visual outcomes and astigmatic changes after femtosecond laser astigmatic keratotomy in femtosecond laser-assisted cataract surgery (FLACS).

Methods

This was a prospective interventional case series. Patients with age-related cataract and corneal astigmatism (1.0–3.0D) were treated with FLACS and femtosecond laser astigmatic keratotomy (FSAK). All patients underwent examinations before and 3 months after surgery; visual acuity, subjective and objective refraction, and corneal astigmatism were evaluated and recorded for all patients by using an OPD-Scan III topographer. Vector analysis of astigmatic changes was performed by using the Alpins vector method.

Results

Twenty-five patients were included in the study. Postoperatively, refractive and corneal astigmatism were both reduced significantly (P < 0.05), concurrent with improved uncorrected distance visual acuity and corrected distance visual acuity. The rate of spectacle use was significantly reduced at 3 months postoperatively (P = 0.001). The mean magnitude of the target-induced astigmatism vector (1.40 ± 0.37D) was slightly higher than the mean magnitude of the surgically induced astigmatism vector (1.22 ± 0.46D). The magnitude of error (− 0.18 ± 0.36D), as well as the correction index (0.88 ± 0.29), demonstrated slight undercorrection. The angle of error was 0.85 ± 13.69°, which was close to zero.

Conclusions

Combined femtosecond laser-assisted cataract surgery and astigmatic keratotomy may be an effective approach to manage preoperative astigmatism in cataract surgery, although slight undercorrection may exist during short-term follow-up.

Trial registration

ChiCTR-TRC-14004977

Comparison of the Rotational Stability of Two Toric Intraocular Lenses in 1273 Consecutive Eyes

PURPOSE

To compare the rotational stability of the 2 most commonly used toric intraocular lenses (TIOLs).

DESIGN

Retrospective cohort study in a single private practice.

SUBJECTS

The study included all patients receiving an Acrysof (n = 626) or Tecnis TIOL (n = 647) over an 18-month period from April 2015 to September 2016. Patients were only excluded if their surgery could not be performed using a digital marking system.

METHODS

All patients had cataract surgery performed in the same surgical center with a similar technique. A digital marking system with limbal vessel registration was used to record the axis of the TIOL at the conclusion of surgery. A dilated examination was performed either later on the day of surgery or the next morning, and the postoperative rotation of the 2 TIOL models was compared. Patients who required a return to the operating room for TIOL repositioning were examined to determine risk factors for reoperation and subsequent outcomes.

MAIN OUTCOME MEASURES

The primary outcome measure was the percentage of eyes with TIOL rotation >5 and >10 degrees. The second main outcome was likelihood of requiring return to the operating room to reposition a rotated TIOL.

RESULTS

The Acrysof TIOL was less likely to rotate postoperatively, with 91.9% of eyes rotated ≤5 degrees at the first postoperative check compared with 81.8% of Tecnis TIOL eyes (P < 0.0001). This difference persisted for rotation ≤10 degrees (97.8% Acrysof vs. 93.2% Tecnis, P = 0.0002) and ≤15 degrees (98.6% Acrysof vs. 96.4% Tecnis, P = 0.02). The mean rotation was 2.72 degrees (95% confidence interval 2.35-3.08 degrees) for Acrysof and 3.79 degrees (95% confidence interval 3.36-4.22 degrees) for Tecnis TIOLs (P < 0.05). The Tecnis TIOL showed a strong predisposition to rotate counterclockwise, unlike the Acrysof. More Tecnis TIOL patients required repositioning (3.1% vs. 1.6%), but this did not reach statistical significance (P = 0.10). Refractive outcomes were similar between the 2 groups.

CONCLUSIONS

The Acrysof TIOL showed significantly greater rotational stability than the Tecnis TIOL.

Optimizing outcomes with toric intraocular lenses

Toric intraocular lenses (IOLs) are the procedure of choice to correct corneal astigmatism of 1 D or more in cases undergoing cataract surgery. Comprehensive literature search was performed in MEDLINE using “toric intraocular lenses,” “astigmatism,” and “cataract surgery” as keywords. The outcomes after toric IOL implantation are influenced by numerous factors, right from the preoperative case selection and investigations to accurate intraoperative alignment and postoperative care. Enhanced accuracy of keratometry estimation may be achieved by taking multiple measurements and employing at least two separate devices based on different principles. The importance of posterior corneal curvature is increasingly being recognized in various studies, and newer investigative modalities that account for both the anterior and posterior corneal power are becoming the standard of care. An ideal IOL power calculation formula should take into account the surgically induced astigmatism, the posterior corneal curvature as well as the effective lens position. Conventional manual marking has given way to image-guided systems and intraoperative aberrometry, which provide a mark-less IOL alignment and also aid in planning the incisions, capsulorhexis size, and optimal IOL centration. Postoperative toric IOL misalignment is the major factor responsible for suboptimal visual outcomes after toric IOL implantation. Realignment of the toric IOL is needed in 0.65%–3.3% cases, with more than 10° of rotation from the target axis. Newer toric IOLs have enhanced rotational stability and provide precise visual outcomes with minimal higher order aberrations.

The refractive outcome of Toric Lentis Mplus implant in cataract surgery

AIM

To evaluate the refractive outcome of Toric Lentis Mplus intraocular lens (IOL) implant.

METHODS

This is a retrospective case series. Consecutive patients with corneal astigmatism of at least 1.5 D had Toric Lentis Mplus IOL implant during cataract surgery. The exclusion criteria included irregular astigmatism on corneal topography, large scotopic pupil diameter (>6 mm), poor visual potential and significant ocular comorbidity. Postoperative manifest refraction, uncorrected distance visual acuity (UDVA), best-corrected distance visual acuity (BCVA), uncorrected intermediate visual acuity (UIVA) at 3/4 m and uncorrected near visual acuity (UNVA) were obtained.

RESULTS

There were 70 eyes from 49 patients in this study. Patients were refracted at a median of 8.9wk (range 4.0 to 15.5) from the operation date. Sixty-five percent of eyes had 6/7.5 (0.10 logMAR) or better, and 99% 6/12 (0.30 logMAR) or better postoperative UDVA. Eighty-nine percent could read Jaeger (J) 3 (0.28 logMAR) and 95% J5 (0.37 logMAR) at 40 cm. The median magnitude of astigmatism decreased from 1.91 D to 0.49 D (Wilcoxon, P<0.001) after the operation. The range of the cylindrical error was reduced from 1.5-3.95 D (keratometric) preoperatively to 0.00-1.46 D (subjective refraction transposed to corneal plane) postoperatively.

CONCLUSION

Toric Lentis Mplus IOL has good predictability in reducing preexisting corneal astigmatism.

Toric Intraocular Lenses in the Correction of Astigmatism During Cataract Surgery: A Systematic Review and Meta-analysis

TOPIC

We performed a systematic review and meta-analysis to evaluate the benefit and harms associated with implantation of toric intraocular lenses (IOLs) during cataract surgery. Outcomes were postoperative uncorrected distance visual acuity (UCDVA) and distance spectacle independence. Harms were evaluated as surgical complications and residual astigmatism.

CLINICAL RELEVANCE

Postoperative astigmatism is an important cause of suboptimal UCDVA and need for distance spectacles. Toric IOLs may correct for preexisting corneal astigmatism at the time of surgery.

METHODS

We performed a systematic literature search in the Embase, PubMed, and CENTRAL databases within the Cochrane Library. We included randomized clinical trials (RCTs) if they compared toric with non-toric IOL implantation (± relaxing incision) in patients with regular corneal astigmatism and age-related cataracts. We assessed the risk of bias using the Cochrane Risk of Bias tool. We assessed the quality of evidence across studies using the GRADE profiler software (available at: www.gradeworkinggroup.org).

RESULTS

We included 13 RCTs with 707 eyes randomized to toric IOLs and 706 eyes randomized to non-toric IOLs; 225 eyes had a relaxing incision. We found high-quality evidence that UCDVA was better in the toric IOL group (logarithm of the minimum angle of resolution [logMAR] mean difference, -0.07; 95% confidence interval [CI], -0.10 to -0.04) and provided greater spectacle independence (risk ratio [RR], 0.51; 95% CI, 0.36-0.71) and moderate quality evidence that toric IOL implantation was not associated with an increased risk of complications (RR, 1.73; 95% CI, 0.60-5.04). Residual astigmatism was lower in the toric IOL group than in the non-toric IOL plus relaxing incision group (mean difference, 0.37 diopter [D]; 95% CI, -0.55 to -0.19).

CONCLUSIONS

We found that toric IOLs provided better UCDVA, greater spectacle independence, and lower amounts of residual astigmatism than non-toric IOLs even when relaxing incisions were used.

Comparative evaluation of aspheric toric intraocular lens implantation and limbal relaxing incisions in eyes with cataracts and ≤3 dioptres of astigmatism

PURPOSE

To compare the visual outcomes of aspheric toric intraocular lens (IOL) implantation and limbal relaxing incisions (LRI) for management of coexisting age-related cataracts and astigmatism.

METHODS

In this prospective study, sixty eyes of 60 patients with visually significant cataract and coexisting corneal astigmatism ≤3 dioptres (D) were randomised to undergo phacoemulsification with either aspheric toric IOL or aspheric monofocal IOL with LRI. The main outcome measures were postoperative 3-month uncorrected visual acuity (UCVA), contrast sensitivity, rotational stability of the toric IOL and spectacle independence.

RESULTS

The postoperative UCVA, contrast sensitivity and refractive astigmatism were significantly better than the baseline measurements for both groups (p≤0.001). There was no significant difference detected for these parameters between LRI and toric IOL groups postoperatively (p≥0.119). At both postoperative month 1 and 3, the percentages of eyes in need of spectacles were lower in toric group than LRI group (p≤0.030). IOL misalignment was noted in three eyes in the toric IOL group (mean misalignment 7.67±4.04°). On vector analysis, magnitude of error (ME) was negative in the LRI group indicating undercorrection, whereas the ME was close to zero for toric group.

CONCLUSIONS

Both toric IOL implantation and LRI were effective in correcting corneal astigmatism ≤3 D during phacoemulsification, while LRI tended to undercorrect astigmatism.