Regular Corneal Astigmatism Research Articles

Rotational stability of plate-haptic toric intraocular lenses implantation with a capsular tension ring: a prospective randomized paired-eye study.

To compare the rotational stability and visual outcomes of plate-haptic toric intraocular lenses (IOLs) with and without a capsular tension ring (CTR) in paired eyes. Eye and Ears, Nose, and Throat Hospital of Fudan University, Shanghai, China. Prospective, randomized, paired-eye study. Patients with bilateral cataracts and coexisting regular corneal astigmatism were enrolled. The two eyes of each patient were randomly assigned to the CTR or non-CTR (NCTR) group. Both eyes of each patient were subjected to phacoemulsification and toric IOL implantation. CTRs were implanted into the eyes of the CTR group. All patients were followed-up for 12 months; the uncorrected distance visual acuity (UDVA), residual astigmatism (RAS), and rotational degree of the toric IOL were recorded. In total, 186 eyes of 93 patients were eligible for analysis. At each visit, UDVA improved significantly after surgery in all eyes (p < 0.001). The mean rotational degree and RAS were significantly smaller in the CTR group at the 2-week visit (p < 0.05). The toric IOLs achieved rotational stability at 1 week postoperatively in the CTR group while at 2 weeks postoperatively in the NCTR group. In the subgroup analyses, CTR co-implantation significantly reduced the 2-week IOL rotation in eyes meeting specific ocular measurements. CTR co-implantation could increase the rotational stability of plate-haptic toric IOLs, by reducing the amount of the IOL rotation in the early postoperative period and accelerating the stabilization of IOLs in the capsular bag.

Assessment of the refractive outcomes of patients with regular corneal astigmatism implanted with high-power toric intraocular lenses.

To describe the refractive outcomes of eyes with high regular corneal astigmatism undergoing age-related cataract surgery. Astigmatic patients who underwent cataract surgery with implantation of high-power XY1AT HOYA® toric lenses (IOLs) (≥ T5) between March 2020 and June 2022 were included. Patients were divided into 2 groups based on the type of Total Corneal Astigmatism (TCA) used for the toric IOL calculation: group 1 = TCATK- 700 (TCA measured by the Iol Master 700®) and group 2 = TCAAK- 700 (TCA estimated from the anterior keratometry of the Iol Master 700® and using the Abulafia-Koch regression). The best-uncorrected (UDVA) and corrected (CDVA) distance visual acuity, subjective spherical equivalent (SSEq) and subjective residual cylinder (SRC) were assessed at 1 month. The predictability (centroid [CEPA] and mean absolute error in predicted astigmatism [MAEPA]) of the 2 TCA assessment methods was analyzed. 96 eyes of 74 patients were included. In the whole cohort, the UDVA was 0.14 ± 0.19 logMAR, the CDVA was 0.04 ± 0.07 logMAR. Postoperative SSEq was - 0.24 ± 0.53D. Postoperative SRC was - 0.48 ± 0.56D. The UDVA, SSEq and SRC did not significantly differ between groups. The MAEPA was significantly better with TCAAK-700 compared to TCATK-700: 0.58 ± 0.52D versus 0.65 ± 0.55D (p = 0.01). No significant difference was observed for the CEPA (p(x) = 0.09, p(y) = 0.19). XY1AT HOYA® toric IOLs are a very good alternative even in case of high toricity. Residual astigmatism predictability is high, it would be better with TCAAK- 700. This data should be confirmed with a larger sample of patients.

Surgical approaches to correct corneal astigmatism at time of cataract surgery: a mini-review.

Among refractive errors, astigmatism is the most common optical aberration, where refraction changes in different meridians of the eye. It causes blurred vision at any distance and includes corneal, lenticular, and retinal astigmatism. Cataract surgery used to cause a progressive increase in the pre-exisiting corneal astigmatism because of creating a surgically induced astigmatism, for example, a large size surgery incision. The development of surgical techniques during last decades has made cataract surgery interchange to treat preoperative corneal astigmatism at time of surgery. Nowadays, three surgical approaches can be used. By placing a sutureless clear corneal incision on the steep meridian of the cornea, a preoperative corneal astigmatism less than 1.0 D can be corrected. Single or paired peripheral corneal relaxing incisions (PCRIs) provide 1.0-3.0 D corneal astigmatism correction. PCRIs are typically used for treating 1.0-1.5 D of regular corneal astigmatism, if more than 2.0 D, the risk of overcorrection and irregular astigmatism is increased. When toric intraocular lenses (IOLs) are unavailable in markets, PCRIs are still a reasonable option for patients with up to 3.0 D of pre-existing corneal astigmatism. Toric IOLs implantation can correct 1.0-4.5 D of corneal astigmatism. Several IOLs are approved to correct a high degree of corneal astigmatism with cylinder power up to 12.0 D. These approaches can be used alone or in combination.

Modified femtosecond laser-assisted arcuate keratotomy for managing low corneal astigmatism using trifocal intraocular lens implantation in Chinese cataract patients.

To evaluate the visual outcome and astigmatic correction following trifocal intraocular lens (IOL) implantation using the modified femtosecond laser-assisted arcuate keratotomy (FSAK) in Chinese cataract patients with low astigmatism. This retrospective study included consecutive cataract patients with regular corneal astigmatism ranging from 0.75 to 1.5 D who underwent FSAK combined with the trifocal IOL implantation between November 2020 and September 2022. Monocular uncorrected distance visual acuity, uncorrected intermediate visual acuity, uncorrected near visual acuity, and refractive data were collected at the 3-month follow-up. The pre- and post-operative high-order aberrations (HOAs) were recorded. The variation in astigmatism was analyzed using Alpins vector analysis. A total of 27 eyes from 23 patients were analyzed. The monocular uncorrected distance visual acuity (UDVA) (5 m) at the 3-month follow-up was 0.04 ± 0.09 logarithm of the minimum angle of resolution (logMAR), which was significantly improved compared with the preoperative value of 0.95 ± 0.51 logMAR (P <.001). The corneal astigmatism was significantly reduced from 1.24 ± 0.42 D to 0.49 ± 0.34 D (P <.001). The target-induced astigmatism (TIA) was 1.25 ± 0.43 D, the surgically induced astigmatism (SIA) was 1.16 ± 0.52 D, and the difference vector (DV) was 0.5 ± 0.34 D. The magnitude of error (ME) (difference between SIA and TIA) was -0.1 ± 0.41 D, and the correction index (CI) (ratio of SIA to TIA) was 0.93 ± 0.36. The angle of error was 3.92° ± 16.90°. Total HOA was reduced from 0.89 ± 1.11 to 0.41 ± 0.55 (P = 0.184), and the corneal HOA was lowered from 0.17 ± 0.18 to 0.10 ± 0.10 (P = 0.129). Implantation of trifocal IOL following the modified FSAK in Chinese cataract patients exhibited excellent visual efficacy and effectively reduced corneal astigmatism.

Vector Planning: Treating Asymmetrically and Achieving the Minimum Refractive and Regular Corneal Astigmatism

Vector Planning: Treating Asymmetrically and Achieving the Minimum Refractive and Regular Corneal Astigmatism

Accuracy of toric intraocular lens power calculation depending on different keratometry values using a novel network based software platform.

To compare different corneal keratometry readings (swept-source-OCT-assisted biometry and Scheimpflug imaging) with a novel software platform for calculation of toric intraocular lenses. Department of Ophthalmology, Ludwig-Maximilians-University, Munich, Germany. Retrospective, non-randomized, clinical trial. Twenty-three eyes undergoing toric intraocular lens implantation were included. Inclusion criteria were preoperative regular corneal astigmatism of at least 1.00 D, no previous refractive surgery, no ocular surface diseases and no maculopathies. Lens exchange was performed with CALLISTO eye (Zeiss). For each patient, the expected postoperative residual refraction was calculated depending on three different corneal parameters of two different devices: standard K-front (K) and total keratometry (TK) obtained by a swept-source-OCT-assisted biometry system (IOL Master 700, Zeiss) as well as total corneal refractive power (TCRP) obtained by a Scheimpflug device (Pentacam AXL, Oculus). Barrett's formula for toric intraocular lenses was used for all calculations within a novel software platform (EQ workplace, Zeiss FORUM®). Results were statistically compared with postoperative refraction calculated according to the Harris dioptric power matrix. The standard K values (mean PE 0.02 D ± 0.45 D) and TK values (mean PE 0.09 D ± 0.43 D) of the IOL Master 700 reached similar results (p = 0.96). 78% of eyes in both K and TK groups achieved SE within ±0.5 D of attempted correction and all eyes (100%) were within ±1.0 D of attempted correction in both groups. By contrast, the prediction error in the IOL calculation using the TCRP of the Scheimpflug device was significantly greater (mean PE -0.56 D ± 0.49 D; p = 0.00 vs. standard K and p = 0.00 vs. TK) with adjusted refractive indices. Thirty-nine and Ninety-one percentage of eyes in the TCRP group achieved SE within ±0.5 D (p = 0.008 K vs. TCRP and p = 0.005 TK vs. TCRP) and ± 1.0 D (p = 0.14 vs. TCRP) of attempted correction, respectively. All three corneal parameters (standard K, TK, TCRP) performed well in calculating toric IOLs. The most accurate refractive outcomes in toric IOL implantation were achieved by IOL calculations based on swept-source-OCT-assisted biometry. The SS-OCT-based K-front and TK values achieve comparable results in the calculation of toric IOLs.

Evaluation of Clinical Results of Implantation of Toric Intraocular Lenses Including their Rotational Stability.

The aim of the study was to evaluate the clinical results of the implantation of the toric intraocular lens Acrysof IQ Toric SN6AT3_8(Alcon Laboratories, Inc., Fort Worth, TX, USA), including an evaluation of its rotational stability. 30 eyes of 16 patients (4 males, 12 females; mean age 68 years) with regular corneal astigmatism ranging from -1.5 to -4.0 Dcyl were included in this retrospective study. All the patients underwent uncomplicated cataract surgery with the implantation of a toric intraocular lens (TIOL) at the Department of Ophthalmology of the Faculty of Medicine and Dentistry of Palacký University in Olomouc and University Hospital Olomouc during the course of 2020. Follow-up examinations were performed 3-6 months after cataract surgery. We monitored the resulting uncorrected distance visual acuity (UDVA), postoperative refraction, rotational stability of the implanted lens and subjective patient satisfaction. mean preoperative corneal astigmatism was -2.41 ±0.67 Dcyl. UDVA improved from a mean value of 0.45 ±0.25 (expressed in decimal Snellen optotype values) to 0.91 ±0.16. The spherical equivalent value of 0.41 ±2.92 improved to -0.11 ±0.27 postoperatively. The mean deviation from the planned axis was 4.87 ±4.75. Subjective satisfaction was rated by patients on a scale of 1-5, with a mean score of 1.5. TIOL implantation is a safe and effective solution for patients with corneal astigmatism and cataract. Our results demonstrate improved UDVA, rotational stability of the TIOL and subjective patient satisfaction with the outcome of the surgery.

Diagnostic Importance of OCT Pachymetry in Keratoconus.

To demonstrate changes in distance and near fusional vergence measured with prism bars, while compensating for present heterophoria using current ametropia correction. In addition, to determine the differences in values of the AC/A ratio determined by the heterophoric (calculation) and gradient methods. The basic sample includes 19 subjects with a mean age of 21.5 ±3.0 years (min. 18, max. 27). We used the Von Graefe technique for examination of distance and near phoria, and prism bars for examination of fusion vergences measured in prism diopters. We divided the basic cohort into six research sets according to the size of distance and near heterophoria. This was a cohort of patients with distance (D OR) and near orthophoria (N OR), a cohort of patients with distance (D EX) and near exophoria (N EX) and a set of patients with distance (D ES) and near esophoria (N ES). In the case of both groups with exophoria (distance, near) we found a statistically significant result only for negative fusion vergence (NFV). There was a statistically significant increase in NFV in the sample with distance and near exophoria (D EX, p = 0.01 and B EX, p = 0.02, respectively). In our study, we also demonstrated a statistically significant difference (p &lt; 0.001) in the values of the AC/A ratio measured by the gradient and heterophoric methods. The values determined by the gradient method are lower (3.0 ±1.1 pD/D versus 5.8 ±0.9 pD/D) than by the heterophoric method. By comparing fusion vergence values in patients with exophoria and orthophoria, we demonstrated that in the presence of distance or near exophoria there is an increase in ipsilateral fusion vergence. In the case of an increase in ipsilateral fusion vergence, the finding was statistically significant both distance and near (p = 0.01 and p = 0.02, respectively). By contrast, we were unable to prove this fact in the group of patients with esophoria. In our study, we also demonstrated a statistically significant difference (p &lt; 0.001) in the values of the AC/A ratio measured by the gradient and heterophoric methods. The values determined by the gradient method are lower (3.0 ±1.1 pD/D versus 5.8 ±0.9 pD/D) than by the heterophoric method.

Symmetrical femtosecond laser arc incision in correcting corneal astigmatism in cataract patients.

To evaluate the effect of symmetrical arc incision correcting corneal astigmatism in femtosecond laser-assisted phacoemulsification (FLACS). This study enrolled patients with cataract combined with regular corneal astigmatism of >0.75 D, who underwent FLACS. Symmetrical arc incision was set at 8 mm diameter and 85% depth. The follow-up time was 3-24mo (4.92±3.49mo). Pentacam recorded the corneal astigmatism and higher-order aberration at pre-operation and post-operation. The changes in corneal astigmatism were analyzed by Alpins method. The correlation of astigmatism type, age, corneal horizontal diameter, corneal thickness, arc incision length, and correction index (CI) was analyzed, and the residual corneal astigmatism was compared with the residual whole eye astigmatism. Totally 79 patients (102 eyes) were enrolled, 10 patients had corneal epithelial injury, 1 patient occurred corneal epithelial hyperplasia. The corneal astigmatism was 1.23±0.38 D pre-operation, and decreased to 0.76±0.39 D post-operation (t=10.146, P=0.000). Corneal high-order aberration was 0.17±0.08 µm pre-operation and 0.24±0.11 µm post-operation (t=-5.186, P=0.000). The residual corneal astigmatism and residual whole eye astigmatism were no significant difference (t=-0.347, P=0.729). Using Alpin's method, the following were determined: target-induced astigmatism (TIA) =1.23±0.38 D, surgery-induced astigmatism (SIA) =0.77±0.45 D, difference vector (DV)=0.77±0.39 D, and CI=0.54±0.28. Age, astigmatism size, corneal horizontal diameter, corneal thickness, and arc incision length were not correlated with CI. The CI for against the rule astigmatism (ATR) was better than that for with the rule astigmatism (WTR; P=0.001). Femtosecond laser-assisted astigmatic keratotomy has better CI of ATR, but increase higher-order corneal aberration. CI is not ideal, it's not a perfect choice if we pursue ideal correction effect.

Accuracy of Astigmatism Calculation with the Barrett, Panacea, and enVista Toric Calculators.

To evaluate residual refractive astigmatism using the Panacea and enVista toric calculators, compared to the gold-standard Barrett toric calculator. A retrospective and comparative study was conducted in one center. We reviewed the medical records of all patients with a diagnosis of senile cataracts and regular corneal astigmatism, without previous corneal or intraocular surgery, who underwent phacoemulsification with implantation of a toric intraocular lens, who had pre- and postoperative corneal topography, biometry, and refraction measurements. The frequency of preoperative astigmatism according to the axis was 70 (84%) eyes showing with-the-rule (WTR) astigmatism, 9 (14%) eyes with against-the-rule (ATR) astigmatism, and 1 (2%) eye with oblique astigmatism. Regarding astigmatism prediction errors, there were statistically significant differences between the enVista and Panacea calculators (median of 0.39, 0.18, and 0.52 for Barrett, enVista, and Panacea, respectively). The residual astigmatism prediction error centroid was similar for the Barrett and enVista toric calculators, and both were lower compared to the Panacea calculator (x-component p < 0.001). The enVista toric calculator incorporating the Emmetropia Verifying Optical (EVO) toric calculator provides similar results to the gold-standard Barrett calculator.

Comparison of cataract patients with regular corneal astigmatism after implantation of extended range-of-vision and bifocal toric intraocular lenses.

To compare the postoperative visual acuity and visual quality between extended range-of-vision and multifocal toric intraocular lens (IOLs) after implantation in cataract patients with regular corneal astigmatism. Department of Ophthalmology, the Second Hospital of Jilin University, Changchun, Jilin Province, China. Retrospective and single-center study. The study involved implanting the Tecnis Symphony (ZXR00IOL) or the bifocal toric (ZMTIOL) in patients undergoing cataract surgery. Three months after surgery, lens performance was evaluated using distance, intermediate, and near visual acuity tests, defocus curves, the modulation transfer function (MTF), a visual function index questionnaire (VF-14), and the adverse optical interference phenomena. The 3-month postoperative follow-up found that both groups had good corrected distance vision. The ZMT group had better-uncorrected distance visual acuity and near visual acuity (p < 0.05). However, the ZXR group showed better uncorrected intermediate visual acuity (p < 0.05) and visual continuity. Overall astigmatism in the postoperative ZMT group was significantly lower than that in the pre-operative group (p < 0.05). The ZMT group had lower total high-order aberrations (tHOs), higher MTF values, and higher VF-14 scores (p < 0.05). Finally, the ZXR group exhibited reduced halo and glare phenomena (p < 0.05). We found that ZMT can effectively correct a corneal astigmatism of 1.0-1.5 D and ZXR can improve patient outcomes regarding subjective optical quality and range of vision. These findings have the potential to improve future astigmatism treatment options.

Наш опыт имплантации торических интраокулярных линз

Рurpose. To analyze the results of cataract phacoemulsification with implantation of toric intraocular lenses. Methods. We conducted a retrospective analysis of the results of cataract phacoemulsification with concomitant regular corneal astigmatism of 1.5 D or more. 32 patients (42 eyes) were implanted with toric intraocular lenses: 11 MX 60T lenses (BAUSCH+LOMB) and 31 Torica aAY lenses (HumanOptics). Results. Intraocular lens rotation less than 5 ° was recorded in 40 eyes (95.2 %). In 2 patients, the deviation of Torica aAY lenses was 10–15 °, which required their surgical reposition. All patients achieved an increase in uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA). UCVA after surgery increased by an average of 0.5 (from 0.13±0.03 to 0.63±0.08), and then remained stable. BCVA increased by 0.33 (from 0.37±0.06 to 0.7±0.06) in the early postoperative period, and by another 0.09 (0.79±0.04) in the late period. Mean value of the spherical component of refraction decreased in the early postoperative period by 4.1 D (from 5.05±0.45 to 0.94±0.22), in the late period a slight increase by 0.09 D was recorded. The value of the cylindrical component decreased after the operation by an average of 2.24 D (from 3.31±0.22 to 1.07±0.37), further a decrease by another 0.1 D was observed. Conclusion. The implantation of toric intraocular lenses is a relatively inexpensive, technically uncomplicated, effective and safe method of cataract surgery and associated corneal astigmatism correction. Key words: phacoemulsification; astigmatism; toric intraocular lens.

Scleral sutured toric intraocular lens with pars plana vitrectomy for the correction of corneal astigmatism without capsular support.

To describe the repair of a patient with bilateral subluxed cataract and corneal astigmatism in the setting of a coloboma of the iris, zonules, lens, and retina. Pre-operatively his best corrected acuity was 20/500 OD and 20/200 OS. His pre-operative refraction was -7.25 +1.00 at 080 OD and -7.75 +3.00 at 040 OS. On corneal topography, he had 1.95D and 1.45D of regular astigmatism in the right and left eye respectively. This technique involves pars plana vitrectomy in combination with the placement of a MX60 toric intraocular lens fixated to the sclera using 8-0 Gore-Tex in line with the axis of steep corneal astigmatism. The lens is affixed through two pair of nasal and temporal sclerotomies, with each pair located 3 mm posterior to the limbus and 5 mm apart, centered along the axis of steep astigmatism. Post-operatively the patient was 20/25 uncorrected OD and 20/20 uncorrected OS with a refraction of -0.75 +0.50 at 180 in the OD and -0.75 +1.00 at 180 in the OS. Scleral sutured toric intraocular lens placement and pars plana vitrectomy is a viable solution for patients with regular corneal astigmatism and cataract repair in the absence of zonular support.

Rotational stability of plate haptic toric intraocular lenses after combined 25-gauge vitrectomy and cataract surgery.

To evaluate the postoperative intraocular lens (IOL) rotational stability and residual refractive astigmatism following combined 25-gauge vitrectomy and cataract surgery with implantation of a plate haptic toric IOL. In this retrospective case series, 32 eyes of 32 patients underwent a combined 25-gauge vitrectomy and phacoemulsification for vitreoretinal diseases and cataract with regular corneal astigmatism of at least 1 diopter (D). A plate haptic toric IOL (AT Torbi 709M, Carl Zeiss Meditec AG) was implanted in all eyes. The outcome measures were rotational stability and refractive astigmatism up to 6mo postoperatively as well as the best corrected visual acuity (BCVA). Preoperative refractive astigmatism was 2.14±1.17 D, which was significantly reduced to 0.77±0.37 D six to eight weeks postoperatively and remained stable throughout the observation period (0.67±0.44 D at three months and 0.75±0.25 D at six months; for all groups: P<0.0001 compared to baseline). BCVA improved significantly from 0.36±0.33 logMAR preoperatively to 0.10±0.15 logMAR following surgery (P=0.02). Mean IOL axis deviation from the target axis was 3.4°±2.9° after six to eight weeks and significantly decreased over time (2.4°±2.6° six months after surgery; P=0.04). In one patient IOL, re-alignment was performed. Corneal astigmatism is significantly reduced following combined 25-gauge vitrectomy and cataract surgery. The plate haptic toric IOL position and axis remain stable during the observation period of six months.

Rotational stability of a novel toric intraocular lens with an advanced optical profile.

To examine the rotational stability of a novel toric intraocular lens (TIOL), the Tecnis Eyhance Toric II, over a course of three months. Vienna Institute for Research in Ocular Surgery, Hanusch Hospital Vienna. Prospective, unmasked, single-center study. Fifty eyes of 50 patients with cataract and regular corneal astigmatism ≥ 0.75 D were included. The Tecnis Eyhance Toric II IOL (Johnson & Johnson Vision) was implanted in one eye of each study patient. Images of the alignment axis of the IOL were taken intraoperatively, one hour, one week, and 3 months after surgery. For measurement of TIOL rotation, images were superimposed on basis of ocular landmarks. Uncorrected and corrected distance (4 meters) and intermediate (66 cm) visual acuity were assessed at the 3-months visit. There was no significant difference in rotational position between the intraoperative and 3 months timepoints, with a mean rotation of 1.35° ± 1.46° (p=0.313; n =27). No patients had to undergo repositioning of the TIOL. A significant reduction of refractive cylinder occurred from preoperatively 1.8 ± 1.1 D to 0.40 ± 0.42 D at the 3 months visit (p= 0.001; n=43) Corrected distance visual acuity improved significantly, from 0.28 ±0.16 LogMar preoperatively to -0.01 ± 0.13 LogMar 3 months postoperatively. (p=0.001; n=43). The Tecnis Eyhance Toric II showed a good visual performance with no significant rotation over a course of three months and, therefore, an excellent rotational stability. The intraocular lens showed a good safety profile with no adverse events.

Visual performance and rotational stability of a multifocal toric intraocular lens in myopic eyes.

This study aimed to evaluate the visual performance and rotational stability of the multifocal toric intraocular lens in myopes. This prospective, observational study included patients with an axial length of ≥24.5 mm and regular corneal astigmatism of >1 diopter who underwent phacoemulsification cataract surgery and implantation of a multifocal toric intraocular lens (AT LISA toric 909M). The visual acuity, defocus curves, residual astigmatism, rotational stability, higher-order aberrations (HOAs), modulation transfer function (MTF), spectacle dependence and patient satisfaction were evaluated 3 months after surgery. Forty-three eyes from 30 patients were enrolled in this study. Postoperatively, uncorrected distance and near visual acuities (logMAR) were 0.09 ± 0.08 (standard deviation, SD) and 0.14 ± 0.08, respectively. The defocus curve analysis provided a bimodal curve showing two peaks of maximum vision at 0.0 D and at -3.0 D defocus level. The multifocal toric intraocular lens showed excellent rotational stability; the mean rotation was 4.02 ± 2.49 (SD) degrees at 3 months postoperatively. Refractive predictability was excellent with a mean spherical equivalent of 0.19 ± 0.37 (SD) diopters (D) and a mean refractive cylinder of -0.34 ± 0.39 (SD) D. The diffractive multifocal toric intraocular lens, AT LISA toric 909M, provided effective distance and near visual acuities in myopic eyes. It was a predictable and effective device with good rotational stability for the correction of preexisting astigmatism during cataract surgery. In this study, more than 80% of patients achieved spectacle independence.

Safety and efficacy of toric intraocular lens implantation for more than 5 years

Objective: To evaluate the clinical safety and efficacy of toric intraocular lens (IOL) implantation for more than 5 years. Methods: This study was a prospective cohort study in which subjects were continuously observed over a two-year period (May 2014 to May 2016) in nine hospitals. The study randomly assigned subjects to two groups using a central dynamic randomization system: the study group, which received Proming® IQ toric IOL implants, and the control group, which received AcrySof® IQ toric IOL implants. The subjects completed a one-year follow-up, during which various measures were taken and evaluated, including visual acuity, IOL rotation, postoperative complications, intraocular pressure, and subjective evaluation (preoperatively and at 1 day, 6 months, 1 year, and 5 years post-surgery). The main statistical analysis methods include the Mann-Whitney U test, independent sample t-test, Wilcoxon signed rank test, paired sample t-test, chi-square test, and Fisher's exact test. Results: A total of 45 eyes (26 in the study group and 19 in the control group) completed the five-year continuous observation period. The mean age of the subjects was (72.07±10.67) years and the mean interval from surgery to the last visit was (5.39±0.47) years. After five years, there were no significant differences in uncorrected distance visual acuity (0.20±0.26 vs. 0.16±0.13, t=0.17,P=0.752), best corrected distance visual acuity[0.00(0.00, 0.20) vs. 0.05±0.10, U=188.00, P=0.880], uncorrected near visual acuity[0.50 (0.20, 0.60) vs. 0.42±0.20, t=0.35, P=0.857], and best corrected near visual acuity (0.13±0.16 vs. 0.17±0.23, U=161.00, P=0.884) between the two groups. However, all measures improved significantly from baseline levels in both groups (all P<0.05). Five years after surgery, no matter objective refraction [(-0.67±0.85) D vs. (-0.73±1.08)D] or subjective refraction[-0.50 (-1.00, 0.00)D vs. (0.69±0.87)D], the degree of cylindrical degree is significantly lower than preoperative corneal astigmatism [(1.27±0.49) D vs. (1.34±0.82) D, all P<0.001]. In addition, there were no significant differences in intraocular pressure, subjective evaluation of visual adverse symptoms, distance vision spectacle independence, or overall satisfaction evaluation between the two groups (all P>0.05). The IOL rotation was 3.0°(1.0°, 6.0°) in the study group and 4.0°(2.0°, 6.0°)in the control group (U=185.50,P=0.574), indicating no significant difference between the groups in terms of rotational stability. Five years after surgery, there were 7 cases of posterior capsular opacification in the study group and 4 cases in the control group. There were no cases of IOL glistening in the study group, but 5 cases (26.32%) were observed in the control group. Conclusions: The long-term effects of Proming® toric IOL implantation in correcting cataracts with regular corneal astigmatism are clear after five years, with few complications and stable results.

Comparison of Visual and Refractive Outcome between Two Methods of Corneal Marking for Toric Implantable Collamer Lenses (TICL) in Phakic Eyes

Purpose To compare the efficacy of digital-assisted reference marking for toric implantable collamer lenses (Callisto Eye System) with manual marking technique using a slit lamp markeur. Methods This study included patients that underwent implantation of a toric implantable collamer lens (EVO Visian toric ICL, Staar Surgical). Patients were included if they had a myopia above −3 diopters (D) and regular corneal astigmatism of 0.75 diopters or higher. Between both groups a 1:2 matching regarding similar preoperative level of myopia and astigmatism was performed. Visual and refractive outcomes were evaluated. Vector analysis was performed to evaluate total astigmatic changes. Results This study comprised 57 eyes of 57 patients with 19 eyes in the digital group and 38 eyes in the manual marking group. Postoperatively there were no statistically significant differences between both groups in UDVA (p = 0.467), spherical equivalent (SE) (p = 0.864), sphere (p = 0.761) and cylinder (p = 0.878). Vector analysis showed a slightly more accurate postoperative refractive astigmatism in the manual group (0.26 D at 107° ± 0.50 D) compared to the digital marking group (0.31 D at 107° ± 0.45 D), nevertheless with no statistically significant differences between both groups. Conclusions A digital tracking approach for toric ICL alignment was an efficient and safe method for toric marking with similar results regarding visual and refractive outcomes compared to a conventional corneal marking method. Nevertheless, image-guided surgery helped to streamline the workflow in refractive ICL surgery.

Сравнительная оценка хирургической коррекции роговичного астигматизма торическими ИОЛ с использованием различных кератометрических данных и методов расчета

Purpose. Compare the effectiveness of regular corneal astigmatism correction with toric monofocal IOL using various keratometric data and calculation methods. Material and methods. The study included 28 patients (31 eyes) with age-related cataracts and regular corneal astigmatism who underwent phacoemulsification (n=31) with implantation of a monofocal toric IOL (EnVista Toric). Two groups were formed according to the type of calculation and possible options of keratometric data: 1) keratometric data of IOL-master 500 + online manufacturer's calculator; 2) keratometric data of the anterior and posterior corneal surfaces (Pentacam HR) + Barrett's toric calculator. Results. The mean absolute deviation of the predicted residual astigmatism from the actual one was distributed as follows: 1st group – 0.62±0.62 D, 2nd group – 0.41 ± 0.71 D. The values of the mean absolute vector and mean centroid error in diopters were: 0.80±0.59 D and 0.06 D in 1st group, 0.48±0.65 D and 0.02 D in 2nd group, respectively. Conclusion. When using the measured astigmatism of the anterior and posterior surface of the cornea, Barrett's toric calculator showed the best result. The most accurate forecast of residual astigmatism was obtained using the Barrett calculator in combination with Pentacam keratometry data (Axial\Sagittal (Front), Axial\Sagittal (Back)). Key words: corneal astigmatism, posterior corneal astigmatism, toric IOL, centroid analysis, keratometry, cataract surgery

Интраокулярная коррекция астигматизма у пациентов с измененной архитектоникой роговицы

Implantation of toric intraocular lenses (TIOL) currently occupies a leading place in the correction of astigmatism in cataract phacoemulsification. This procedure does not prolong the time of the operation itself, ensures the stability of the results obtained and the high speed of rehabilitation of patients. However, there are a small number of publications in the available literature on the implantation of toric IOLs in cases of altered corneal topography. The aim is to study the results of cataract phacoemulsification with implantation of toric IOLS in astigmatism and altered corneal architectonics. Material and methods. Phacoemulsification with TIOL implantation was performed in 49 patients (50 eyes) with cataract and regular corneal astigmatism. It was established from the anamnesis that radial keratotomy was performed in 20 patients (20 eyes), through keratoplasty – in 10 patients (10 eyes). Keratoconus was observed in 19 people (20 eyes). The average age of the patients was 57.3 ± 9.7 years. All patients were implanted with a toric lens (TIOL) Acrysof IQ Toric (SN6A T3-T9). Preoperative astigmatism varied in the range of 1.5-6.0 D Visual acuity – from light projection to 0.5 with correction. Additionally, patients underwent keratotopographic studies, anterior segment of the eye, endothelial biomicroscopy. The observation period was up to 6 months. Cataract phacoemulsification was performed on the Centurion (Alcon) device. Results. Intra- and postoperative complications were not noted. In all cases, the THIOL occupied a directional position and maintained rotational stability (the maximum rotation angle was 3°) for the entire observation period. The average the postoperative uncorrected distance visual acuity (UDVA) was 0.52 ± 0.11, there were no statistically significant differences in visual acuity between the three nosologies. The spherical component was 0.35± 0.05, the cylindrical component was 0.73 ± 0.12 D. Conclusion. In patients with cataracts and altered corneal topography, phacoemulsification + TIOL is an effective method of correcting ametropia. Keywords: toric intraocular lenses (TIOL), phacoemulsification, astigmatism, cataract.