Toric Intraocular Lens Axis Research Articles

Clinical examples of correct orientation of a toric intraocular lens in patients with postkeratotomic corneal ectasia

BACKGROUND: Surgical treatment of cataract in patients with postkeratotomic corneal ectasia has various features. First, difficulties arise when calculating the optical strength of an intraocular lens and its cylindrical component and determining the location of the main axes of astigmatism for toric intraocular lens implantation. Additionally, not all modern keratotopography installations are able to accurately determine the refractive power of the cornea in such patients owing to pronounced irregular astigmatism and a large difference in keratometric parameters in the main meridians. CLINICAL CASES DESCRIPTION: Two clinical cases of surgical treatment of cataract in combination with postkeratotomic keratectasia are presented. Patients underwent a standard preoperative ophthalmological examination. TMS-4 Tomey keratotopograph was used to accurately determine the refractive power of the cornea. The optical power of toric intraocular lens were calculated using the Holladay 2 formula with amendments for radial keratotomy and the Johnson Johnson VISIC online calculator. SN6AT9 intraocular lens (Alcon) and a Tecnis ZCT800 toric intraocular lens (Johnson Johnson) were implanted in patients. The orientation of the position of the cylinder axis of toric intraocular lens was performed perpendicular to the most flattened meridian, corresponding to the position of the keratectasia zone, determined by the most expanded keratotomy scar. Before surgery, the best corrected visual acuity of patient M was OD=0.2, OS=0.4 and that of patient K was OD=0.4, OS=0.2. After surgery, the best corrected visual acuity of patient M was OD=0.8, OS=0.8 and that of patient K was OD=0.8, OS=0.7. CONCLUSION: This study aimed to familiarize practicing ophthalmologists, clinical residents, and postgraduates with a possible treatment option for cataracts by phacoemulsification with implantation of a toric intraocular lens in patients with postkeratotomic keratectasia. The resulting high visual acuity and subjective satisfaction of patients indicate the accuracy of chosen treatment tactics. A reliable visual guide for choosing the cylinder axis is the meridian of the greatest degree of keratectasia (cornea flattening), which is determined by the maximally expanded keratotomy scar position. The intraocular lens cylinder axis is oriented perpendicular to the keratectasia meridian. Ultrasound phacoemulsification of cataract with implantation of a toric intraocular lens is an effective method for correcting induced ametropia after radial keratotomy against the background of postkeratotomy keratectasia with high astigmatism.

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.

Outcomes of toric intraocular lens realignment surgery done using slit-lamp method and wavefront aberrometry method.

To compare the slit-lamp method and wavefront aberrometry method based on outcomes of toric realignment surgeries. Tertiary care ophthalmic hospital. Retrospective study. This study included all eyes undergoing toric intraocular lens (TIOL) realignment surgery between January 2019 and December 2021 for which TIOL axis assessment by slit-lamp method and wavefront aberrometry method was available. Data were retrieved from electronic medical records, and we documented demographics, uncorrected visual acuity (UCVA), subjective refraction, and TIOL axis by slit-lamp and wavefront aberrometry methods on postoperative day 1 and day 14. In patients with misalignment, TIOL was realigned to the original position in group 1 (27 patients) and to an axis based on calculations provided by wavefront aberrometer in group 2 (25 patients). Post-realignment surgery, UCVA, subjective refraction, and TIOL axis by slit-lamp and wavefront aberrometry methods were assessed and analyzed. We analyzed 52 eyes and found that the mean preoperative misalignment with the slit-lamp method (44.9° ±20.0°) and wavefront aberrometry (47.1° ±19.5°) was similar. The corresponding degrees of misalignment post-TIOL repositioning surgeries were 5.2° ±5.2° (slit-lamp method) and 4.7° ±5.1° (wavefront aberrometry) (P = 0.615). Both groups showed significant improvement in median log of minimum angle of resolution (logMAR) UCVA and reduction in median refractive cylinder. Slit-lamp method is as good as wavefront aberrometer method to assess TIOL axis. Toric realignment surgery is found to be safe, and realigning TIOL based on either slit-lamp method or wavefront aberrometer method equally improved UCVA and decreased residual refractive cylinder.

Simple Technique for Stabilizing Toric Intraocular Lens during Removal of Ophthalmic Viscosurgical Device

Introduction: The aim of this study was to describe a simple technique for the implantation of toric intraocular lenses (IOLs) with increased stability during ophthalmic viscosurgical device (OVD) removal. Methods: The technique was performed on 20 eyes with 20 patients (mean age: 77.9 ± 9.21 years). The patients had cataract surgery with implantation of a single-piece, acrylic IOL (AcrySof Toric IOL, SN6A; Alcon Laboratories, Inc.). The intraoperative IOL rotation during OVD removal, rotational error of toric IOL axis at 30 min and 24 h after surgery, and mean preoperative and postoperative IOP were evaluated. Images were captured before and after removal of OVD from surgical video, and used to evaluate intraoperative IOL rotation. Results: The mean amount of IOL rotation during OVD removal with the current technique was 0.88 ± 0.93°, which was less than the 10.25 ± 5.50° previously reported for the conventional technique. The rotational error of toric IOL axis at 30 min and 24 h were 3.90 ± 3.71 and 3.05 ± 3.22°, respectively. The mean preoperative IOP and postoperative IOP were 13.84 ± 2.39 and 14.15 ± 4.68 mm Hg, respectively. Conclusions: With the current technique, the toric IOL is stable during OVD removal and repositioning of the IOL during surgery is less likely to be required.

Digital versus slit-beam marking for toric intraocular lenses in cataract surgery

PurposeTo compare the visual outcomes of digital and slit-beam manual marking for toric intraocular lenses (IOL) in cataract surgery.SettingSingle-center, Beijing Tongren Hospital, China.DesignRetrospective study.MethodsAll patients with cataracts and regular corneal astigmatism greater than 0.75 diopters (D) underwent cataract surgery and astigmatism correction between June 2019 and June 2020. To mark the target axis of the toric IOL and the location of the incision, intraoperative digital marking was used by Callisto eye image-guided system in one group, while preoperative manual slit-beam marking was used in the other group. Uncorrected and best-corrected spectacle visual acuity, refraction, toric IOL axis, total higher order aberrations, coma, spherical aberration, and trefoil were evaluated at 1, 4, and 12 weeks postoperatively.ResultsSeventy-two eyes of 58 patients were included. At 3 months after surgery, the mean residual refractive cylinder was 0.42 ± 0.45D in the digital group and 0.39 ± 0.40D in the manual group (P = 0.844). There were no significant differences between groups in spherical equivalent refraction, uncorrected and best-corrected spectacle visual acuity, or the parameters of vector analysis. All toric IOL alignment errors were within 10° of the intended axis, and among them, about 42% of eyes in the digital group and 61% of eyes in the manual group had a rotation of 0–2° (P = 0.038). Trefoil in the manual group decreased postoperatively compared with the digital group (P = 0.012). Other aberration analyses did not reveal any statistical differences between groups.ConclusionsAccurate slit-beam manual marking and digital image-guided marking are equally effective for toric IOL alignment.

Comparison of Visual Outcomes Between Toric Intraocular Lenses and Clear Corneal Incisions to Correct Astigmatism in Image-Guided Cataract Surgery.

PurposeTo compare the astigmatism correction effects of toric intraocular lenses (IOL) and clear corneal incisions during image-guided cataract surgery.MethodsAll patients with regular corneal astigmatism of 0.75–1.5 D underwent cataract surgery and astigmatism correction using the Callisto eye image-guided system. One group had implantation of an AcrySof toric IOL. Another group had implantation of aspheric IOL with 3.0 mm single clear corneal incision (SCCI) on the steep axis. Uncorrected and best-corrected spectacle visual acuity, refraction, and toric IOL axis were evaluated at 1, 4, and 12 weeks postoperatively.ResultsSixty-eight eyes of 68 patients were included. The mean residual refractive cylinder was 0.34 ± 0.40 D in the toric group and 0.64 ± 0.57 D in the SCCI group. There were no significant differences in residual refractive cylinder, spherical equivalent, uncorrected distance visual acuity (UDVA), and best-corrected spectacle visual acuity (BCSVA) between groups. The percentage of the residual cylinder within ± 0.50 D was 75 and 56% for toric and SCCI cases, respectively (p > 0.1). The mean surgical induced astigmatism vector was 0.61 ± 0.29 D in the SCCI group and 1.04 ± 0.38 D in the toric group. The mean magnitude of error was negative (−0.54 ± 0.48 D) and the correction index was <1.0 (p < 0.05) in SCCI group. At 3 months, all toric IOL alignment errors were within 5 degrees from the intended axis.ConclusionsBoth toric IOL and SCCI can correct low and medium astigmatism effectively with the help of a precise image-guided system.

Accuracy of Toric Intraocular Lens Axis Alignment Using Manual Slit Lamp Method and CALLISTO Eye Image-Guided System

Aims: Image-guided systems are the gold standard for determining toric intraocular lens (IOL) axis alignment. However, their high cost prevents widespread use of these systems. As an alternative, a simpler and affordable method could be performed manually using a slit-lamp biomicroscope. This study aims to compare the accuracy of manual toric IOL axis marking using a slit-lamp compared to the CALLISTO eye image-guided system.&#x0D; Study Design: Prospective comparative&#x0D; Methods: In this prospective study, toric IOL axis alignment of 42 eyes with cataract and coexisting corneal astigmatism were evaluated using manual slitlamp method and CALLISTO eye image-guided method. Preoperative and postoperative uncorrected visual acuity, best corrected visual acuity, amount of spherical and astigmatic refractive errors, and postoperative IOL axis alignment were evaluated. Intraclass correlation of the manual method was calculated and the difference of IOL axis alignment to the image-guided method was compared.&#x0D; Results: Toric IOL implantation reduced the amount of astigmatic refractive error from -1.63 ± 0.65 D to -0.50 ± 0.19 D in the image-guided group and from -1.93 ± -0.90 D to -0.87 ± 0.26 D in the manual slitlamp group. As many as 90.5% of eyes in the image-guided group and 81.0% of eyes in the manual slitlamp group reached the target induced astigmatism (p=0.38). Manual axis marking showed intraclass correlation of 99.3%. However, when the manual method was compared to the image-guided method a mean difference in axis alignment of 10.98o (95% confidence interval: 9.32o - 12.63o) was observed.&#x0D; Conclusions: Alignment of toric IOL axis using the manual method demonstrated a consistent result; yet producing a considerable difference to the result of the image-guided method.

A Review of Smartphone Apps Used for Toric Intraocular Lens Calculation and Alignment.

Smartphone apps are becoming increasingly popular in ophthalmology, one specific area of their application being toric intraocular lens (IOL) surgery for astigmatism correction. Our objective was to identify, review and objectively score smartphone apps applicable to toric IOL calculation and/or axis alignment. This review was divided into three phases. A review was conducted on four major app databases (phase I): National Health Service (NHS) Apps Library, Google Play Store, Apple App Store and Amazon Appstore. A systematic literature review (phase II) was conducted to identify studies for included apps in phase I of our study. Keywords used in both searches included: “toric lens”, “toric IOL”, “refraction”, “astigmatism”, “ophthalmology”, “eye calculator”, “ophthalmology calculator” and “refractive calculator”. Included apps were objectively scored (phase III) by three independent reviewers using the mobile app rating scale (MARS), a validated tool that ranks the quality of mobile health apps using a calculated mean app quality (MAQ) score. Phase I of our study screened 2428 smartphone apps, of which six apps for toric IOL calculation and four apps for axis marking were eligible and were selected for quantitative analysis. Phase II of our study screened 477 studies from PubMed, Medline and Google Scholar. Three studies validating two apps (toriCAM, iToric Patwardhan) in a clinical setting as adjunct tools for preoperative axis marking were identified. Phase III ranked Toric Calculator for iPhone (Apple iOS, MAQ 4.13; average MAQ 3.34 ± 0.54) as the highest-scoring toric IOL calculator, and iToric Patwardhan (Android OS, MAQ 4.13; average MAQ 3.41 ± 0.44) was the highest-scoring axis marker in our study. Our review identified and objectively scored ten smartphone apps available for toric IOL surgery adjuncts. Toric Calculator for iPhone and iToric Patwardhan were the highest-scoring toric IOL calculator and axis marker, respectively. Current literature, though limited, suggests that axis marking smartphone apps can achieve similar levels of misalignment reduction when compared to digital systems.

Prevention method of toric intraocular lens rotation after phacoemulsification of cataract using a standard capsule ring

At the same time, phacoemulsification of cataracts remains the most popular surgery. But the problem among phacosurgeons is the correction of existing corneal astigmatism. According to studies, about 30% of the world's population have corneal astigmatism with a strength of 0.75D and above, which leads to a decrease in visual acuity after phacoemulsification of cataracts in the absence of its correction.The most commonly used method to correct corneal astigmatism is the implantation of toric intraocular lenses (TIOL). The main condition for obtaining high visual acuity after TIOL implantation is the location of the astigmatic component of the artificial lens in accordance with the strong meridian of the cornea. The aim of this study was to evaluate the effectiveness of the proposed method of preventing the toric intraocular lens rotation after phacoemulsification of cataracts in the eyes with corneal astigmatism by implantation of a standart capsule ring.Material and methods. The article presents the results of a comprehensive examination of 43 patients (59 eyes) who underwent surgery by phacoemulsification of cataracts with implantation of toric IOL to correct concomitant corneal astigmatism. Corneal astigmatism according to keratometry ranged from 0.5D to 4.25D (average 1.96 ± 0.1 D). Patients were divided into 2 groups. The first group consisted of 26 patients (31 eyes). Patients in this group underwent phacoemulsification with toric IOL implantation according to standard techniques without the use of techniques that prevent rotation of the artificial lens in the postoperative period. The second group included 18 patients (28 eyes) who were operated on according to our proposed prevention method of TIOL rotation. As a result of the study, it was found that rotation of TIOL was detected 6 months after surgery in the I group without the use of developed method in 22 eyes (70.9%), in the II group, where the capsule ring was implanted, rotation occurred in 12 eyes (42.85%). In the II group in all cases, the deviation of the TIOL axis did not exceed 6 degrees. The proposed method of prevention of rotation of TIOL allows to increase the efficiency of phacoemulsification of cataracts.Conclusions. Developed a method of preventing the rotation of the toric intraocular lens using a standard capsule ring, which is implanted and located on top of the haptic support elements of the artificial lens can increase the efficiency of phacoemulsification of cataracts in the eyes with corneal astigmatism, contributes to the rotational stability of the toric lens and provides long-term results of visual functions, reduces the need for repeated surgery due to reposition of the rotated lens and can be recommended for implementation in the practice of ophthalmic surgeons.The use of implantation of a standard capsule ring according to the proposed in this study method prevents the rotation of the toric intraocular lens by more than 6 degrees in all cases, which does not significantly reduce visual acuity and does not require reposition of the artificial lens. This method of preventing rotation of the toric intraocular lens allows to achieve visual acuity of 0.7 and above in 85.6% of cases.

Anterior capsule coverage and rotational stability of an acrylic toric intraocular lens.

To investigate factors related to the rotational stability of an acrylic toric intraocular lens (IOL). Four ophthalmic surgical sites in Japan. Prospective case series. The study included 120 eyes of 120 patients undergoing phacoemulsification and implantation of a toric IOL (AcrySof IQ, Alcon Laboratories, Inc.). At 1 hour postoperatively, the area of continuous curvilinear capsulorhexis (CCC) was measured, and the state of anterior capsule coverage on the IOL optic (total on or partial on) was recorded. The toric IOL axis orientation was assessed at the end of surgery and at 1 hour, 1 week, 1 month, and 6 months postoperatively. Multiple regression analysis was performed to explore any clinical factors relevant to IOL rotation from the end of surgery to 6 months postoperatively. The explanatory variables included age, anterior chamber depth preoperatively, axial length, type of corneal astigmatism (with-the-rule, against-the-rule, or oblique astigmatism), area of CCC, state of anterior capsule overlap on IOL optic (total coverage vs partial coverage), and surgical sites (surgeons). The multiple regression analysis in 110 eyes of 110 patients indicated that anterior capsule overlap on the IOL optic was the only variable associated with IOL rotation at 6 months postoperatively (P = .0482). The mean absolute rotation at 6 months was 1.96 ± 1.81 degrees in the total on group and 3.79 ± 3.12 degrees in the partial on group (P = .0004). Rotational stability of a single-piece, acrylic toric IOL was better in eyes with total anterior capsule coverage than that in those with partial anterior capsule coverage on the IOL optic.

Evaluation of Scheimpflug imaging system as an added tool in improving the accuracy of reference marking (as compared to the slit lamp marking system) for toric intraocular lens implantation.

Purpose:To assess the role of Scheimpflug imaging in improving the accuracy of reference marking for toric IOL implantation.Methods:In this prospective, randomized, clinical trial all patients with cataract and pre-existing significant regular corneal astigmatism, who required implantation of a toric IOL were included in the study, and patients with any ocular pathology or abnormality were excluded. Patients were divided into two groups: For one group of patients, Group I (GI), reference marking was finalized using slit lamp only, and for the second group, Group II (GII), after slit lamp marking, the reference marks were checked using Goniometer of Scheimpflug imaging. The primary outcome was to determine the axis of toric intraocular lens (IOL) postoperatively (within 1 hour) and compare it with the desired axis of placement.Results:We found a statistically significant difference in the two groups (P < 0.001) suggesting Group II (4 step technique) is better than Group I (3 step technique).Conclusion:Scheimpflug imaging, an extra step preoperatively, is an effective measure to reduce errors in reference marking and thereby improving the refractive outcome of toric intraocular lens.

Accuracy of toric intraocular lens implantation using automated vs manual marking

BackgroundAccurate alignment of toric intraocular lens (TIOL) to steep corneal astigmatic axis is important to achieve effective postoperative results. The authors compare the accuracy of astigmatism correction using automated and manual marking in TIOL implantation during cataract surgery.MethodsOne hundred thirty-two eyes with nuclear density from Grade 2 to 4 were randomly subdivided into 2 groups (automated and manual marking). All patients underwent manual marking and the steep axis was compared to SensoMotoric Instruments (SMI). After phacoemulsification, 62 patients underwent toric IOL implantation using the SMI and 70 patients underwent toric IOL implantation using manual marking. Intraoperative measurement was the steep axis difference. Clinical measurements included preoperative and postoperative best corrected visual acuity (BCVA), and TIOL axis.ResultsThe intraoperative steep axis difference between SMI and manual marking was 7.86 ± 6.4 degrees. The difference between the preoperative steep axis and the postoperative TIOL axis using SMI (3.63 ± 1.12 degrees) was significantly lower than that using manual marking (8.29 ± 2.23 degrees) (P < 0.05).ConclusionsThe steep axis measurements may be different when using SMI vs. manual marking. The SMI is more accurate than manual marking for TIOL implantation during cataract surgery.Trial registrationCurrent Controlled Trials ISRCTN12294725, Retrospectively registered, on 20 July 2018.

Early Postoperative Rotational stability and its related factors of a single-piece acrylic toric intraocular lens

PurposeIn the present study, we aimed to evaluate the early postoperative rotational stability of TECNIS toric intraocular lens (IOL) and analyse its correlation with preoperative and intraoperative parameters.MethodsA total of 102 eyes from 87 cataract patients who underwent implantation of TECNIS toric IOL during July 2016 to November 2017 were enrolled in this retrospective study. Preoperative parameters including corneal astigmatism, axial length (AL), lens thickness (LT), anterior chamber depth (ACD) and sulcus-to-sulcus (STS), were determined. The area of capsulorhexis was measured with Rhinoceros 5.0 software. The follow-up examinations including the residual astigmatism (RAS) and postoperative toric IOL axis, were performed at 1 month and 3 months after surgery.ResultsRAS was −0.84 ± 0.88 D at 1 month and −0.81 ± 0.89 D at 3 months after surgery. The rotation of toric IOL at 3 months was 4.83 ± 3.65°. The Pearson’s r of ACD, horizontal and vertical STS, and toric IOL target axis was 0.011, 0.039, 0.045 and 0.082. The toric IOL rotation was positively correlated with the area of capsulorhexis (r = 0.522, P = 0.0003), LT (r = 0.288, P = 0.003) and AL (r = 0.259, P = 0.009). As for the area of capsulorhexis, the regressive equation was: y = 0.682 × −13.105, demonstrating that the diameter of capsulorhexis should be controlled within 5.8 mm to maintain the toric IOL rotation within 5.0°.ConclusionsTECNIS toric IOLs possessed great early postoperative rotational stability. The area of capsulorhexis, AL and LT were positively correlated with postoperative rotational stability. A capsulorhexis within 5.8 mm had an important significance in improving rotational stability.

Comparison of clinical outcomes of toric intraocular lens, Precizon vs Tecnis: a single center randomized controlled trial

BackgroundTo compare the clinical outcome of Precizon toric intraocular lens (IOL) (Ophtec Inc.) to that of Tecnis toric IOL (Abbott Medical Optics Inc.).MethodsThis randomized comparative study included 40 eyes (Precizon, 20 eyes; Tecnis, 20 eyes) of 40 patients with visually significant cataract and corneal astigmatism who underwent cataract surgery. Changes in uncorrected distant visual acuity (UCDVA), best corrected distant visual acuity (BCDVA), uncorrected intermediate visual acuity (UCIVA), refraction, residual astigmatism, rotation of the IOL axis, and higher order aberrations at 3 months postoperatively were evaluated. Vector analysis was performed using the Alpins method.ResultsBoth groups showed significant reduction in refractive astigmatism after the surgery (Precizon: − 1.06 ± 0.94 Diopter (D) to − 0.31 ± 0.29 D, p = 0.042; Tecnis: − 1.83 ± 1.29 D to − 0.41 ± 0.33 D, p = 0.015). There was no significant (p > 0.05) difference in postoperative UCDVA, BCDVA, or residual astigmatism between the two groups, although a tendency of better UCIVA was observed in the Precizon group. Vector analysis parameters showed no statistically significant difference beween groups(P > 0.05). Significant difference in rotation of toric IOL axis was found between the two groups (Precizon: 1.50° ± 0.84, Tecnis: 2.56° ± 0.68, p = 0.010). Spherical aberration in the Precizon group was significantly (p = 0.005) lower than that in the Tecnis group.ConclusionsThe Precizon toric IOL group had better rotational stability at 3-month postoperatively. Both Precizon toric IOL and Tecnis toric IOL could be effectively used by cataract surgeons to correct preexisting corneal astigmatism through cataract surgery.Trial registrationhttp://clinicaltrials.gov, NCT03085901, retrospectively registered on 21 March 2017.

Rotational stability and visual performance 3 months after bilateral implantation of a new toric extended range of vision intraocular lens.

PurposeTo evaluate the clinical outcomes after implantation of Symfony® toric extended range of vision (ERV) intraocular lenses (IOLs) in subjects with preoperative corneal astigmatism.SettingIfocus Øyeklinikk, Haugesund, Norway.DesignProspective non-comparative study.Patients and methodsThe study population consisted of 30 patients, with preoperative corneal astigmatism between 0.88 and 3.29 D, undergoing bilateral cataract removal or refractive lens exchange with implantation of Tecnis Symfony toric ERV IOLs. Main outcome measures were visual acuity, refraction, IOL axis rotational stability, patient and surgeon satisfaction, photic phenomena, and quality of life at 3 months.ResultsPostoperatively, mean binocular uncorrected distance, intermediate, and near visual acuities (logMAR) were −0.05±0.11, −0.03±0.08, and 0.09±0.10, respectively. A significant reduction in manifest cylinder (P<0.001) and spherical equivalent (P=0.001) was found after 3 months. Monocular and binocular corrected distance visual acuity also improved significantly with surgery (P<0.001). In terms of binocular uncorrected intermediate and near visual acuity, a total of 96% and 82% of patients achieved 0.1 logMAR (Snellen: 20/25) or better, respectively. Toric IOL axis showed a median rotation of 2.0 degrees (range 0.0–16.0 degrees) from the end of surgery to 3 months. The median patient satisfaction scores for distance, intermediate, and near vision were 9.0, 9.0, and 8.0, respectively. Fifty percent of patients reported complete spectacle independence and most patients (89%) were not bothered by any photic phenomena.ConclusionBilateral implantation of the Symfony toric ERV IOL appeared to be safe and achieved good visual performance and high satisfaction.

Résultats réfractifs et évaluation de la précision du positionnement des implants toriques à l’aide d’un système d’alignement automatisé

To compare precision in toric intraocular lens (TIOL) alignment and refractive outcomes between an intraoperative automated digital marker system and the conventional manual-ink marking. Prospective single center study including consecutive patients undergoing uneventful cataract surgery with corneal astigmatism greater than 1diopter. Total corneal astigmatism was measured using a placido-dual Scheimpflug system (GalileiG4®, Ziemer). Acrysof® SN6AT (Alcon) TIOL's were implanted, and patients were divided into 2groups, the digital group (Verion®, Alcon) and the ink-marking group (Pendular marker, AMO). Mean error in TIOL axis, visual acuity and residual astigmatism were analyzed at 3days, one month and 6months after surgery. In total, 45eyes of 30patients were included (n=25digital group, n=20ink-marking group). The mean preoperative total corneal astigmatism was 1.71±0.53diopters. At one month, there was a significantly lower mean average error in TIOL axis in the digital group compared to the ink-marking group (2.6±2.3° and 6.4±2.8° respectively, P=0.009). At 6months, these results remained statistically significant. Mean residual astigmatism was 0.7±0.4diopters at one month, without significant difference between the two groups (P=0.9). The rate of misalignment less than or equal to 5° was 86% (n=25) in the digital group and 63% (n=20) in the ink-marking group (P=0.05). Intraoperative digital marker system is associated with better TIOL alignment accuracy and better reproducibility than the manual ink-marking method.

Evaluation of postoperative toric intraocular lens alignment with anterior segment optical coherence tomography

We describe the use of a simple tool to evaluate the postoperative alignment of toric intraocular lenses (IOLs). The entire anterior segment is scanned using anterior segment optical coherence tomographyand analyzed with an internal dedicated tool. A topographic map is displayed along with an anterior segment image, including a linear axis marker centered on the corneal apex. The marker can be rotated until it is aligned with the line connecting the IOL marking dots, precisely reproducing the IOL astigmatic axis, which is measured in angle degrees. The value of the IOL astigmatic axis is compared with the value of the astigmatic axis shown in real time on the same screen in the topographic map. Evaluating the alignment of a toric IOL axis simultaneously with the topographic astigmatic axis eliminates the potential errors that result from head tilting and strictly correlates with the astigmatic correction achieved.

Combined Special Capsular Tension Ring and Toric IOL Implantation for Management of Astigmatism and High Axial Myopia with Cataracts

Aim: This study aimed to compare the effects of toric intraocular lens (IOL) implantation with a capsular tension ring and toric IOL implantation only in patients with axial myopic astigmatism who had undergone cataract surgery. Methods: Of 34 patients with axial myopia, 16 patients who had received IOL and capsular tension ring (CTR) implantation were included in the combined group and 18 patients who received toric IOL implantation only were included in the simple group. Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA) were evaluated by measuring subjective refraction, residual astigmatism, and the toric IOL axis six months post-surgery. Results: At six months postoperatively, the UCVA for the combined and simple groups was 4.6 ± 0.1 and 4.5 ± 0.2, respectively, a statistically significant difference (t = 3.531, P<0.05). The toric IOL in all of the cases was located in the capsular sac, but there were more cases with IOL rotation (12 eyes) in the simple group than in the combined group (4 eyes). The rotation angles were 20°~30° (one eye), 10°~20° (four eyes), and <10° (seven eyes) compared with 2°~5° (four eyes). The residual astigmatism was –0.50 ± 0.25 D in the combined group, not a significant difference from the predicted residual astigmatism (–0.35 ± 0.13 D). There was a significant difference in the simple group (–1.25 ± 0.33 D) when the predicted residual astigmatism was compared (–0.37 ± 0.11 D) (t = –9.511, P < 0.01). Conclusions: In patients with axial myopic astigmatism, CTR can effectively increase the rotational stability of a toric IOL, achieving improvement in corneal astigmatism and visual acuity.

Clinical Outcomes After Cataract Surgery With a New Transitional Toric Intraocular Lens.

To evaluate the visual outcomes of patients who underwent cataract surgery with implantation of a transitional toric monofocal intraocular lens (IOL) (Precizon Toric IOL, model 565; Ophtec BV, Groningen, The Netherlands). In this prospective case series, 51 eyes of 39 patients with cataract and regular keratometric astigmatism between 1.00 and 4.50 diopters (D) that had phacoemulsification with implantation of a Precizon Toric IOL were included. Over a 4-month follow-up period, the main outcome measures were uncorrected and corrected distance visual acuities (UDVA and CDVA, respectively), spherical equivalent (SE) refraction, astigmatism outcomes evaluated according to the Alpins method, the IOL's rotational stability, and higher order aberrations. At the 4-month follow-up visit, mean UDVA was 0.06 ± 0.1 logMAR (range: 0.4 to -0.18 logMAR) (P < .001) and mean CDVA was -0.00 ± 0.07 logMAR (range: 0.15 to -0.18 logMAR) (P < .001). UDVA was 0.3 logMAR or better in 50 (98%) eyes and 0.1 logMAR or better in 42 (82%) eyes. Mean SE refraction was -0.19 ± 0.38 D (range: -1.13 to +0.50 D), with 44 (86%) eyes within ±0.50 D of the attempted correction. Mean target induced astigmatism was 1.96 ± 0.94 D (range: 0.70 to 4.50 D) and mean surgically induced astigmatism was 1.85 ± 1.01 D (range: 0.07 to 4.64 D). Mean correction index was 0.87 (range: 0.07 to 2.29 D). Mean toric IOL axis rotation was 1.98° ± 1.78° (range: 0° to 7°). Ocular aberrometry was within normal values. The implantation of the Precizon Toric IOL in patients with cataract and corneal astigmatism provided excellent visual outcomes, predictability of refractive results, rotational stability, and good optical performance. [J Refract Surg. 2016;32(7):452-458.].

Effect of posterior corneal astigmatism on power calculation and alignment of toric intraocular lenses: Comparison of methodologies

To compare the accuracy of different methods that consider posterior corneal curvature in toric intraocular lens (IOL) calculations. Ein-Tal Eye Center, Tel-Aviv, Israel. Retrospective comparative case series. Consecutive cases of toric IOL implantation and preoperative measurements by optical biometry with optical low-coherence reflectometry (OLCR) (Lenstar LS 900) and a Scheimpflug camera (Pentacam) were retrospectively reviewed. Five methods of toric IOL calculation were compared as follows: (1) anterior corneal astigmatism using OLCR, (2) application of the Baylor nomogram, (3) posterior tomography combined with anterior corneal measurements using vector summation, (4) the Scheimpflug camera's true net power, and (5) total corneal refractive power. Toric IOL astigmatic power and axis, aiming for the lowest residual astigmatism, were selected according to these methods. Simulated residual refraction was calculated for each method based on manifest refraction and measured IOL alignment more than 3 weeks after surgery. The study included 115 eyes of 92 patients. The median simulated residual astigmatism was lower when based on vector summation of anterior and posterior astigmatisms than with calculations based on anterior corneal measurements only, application of the Baylor nomogram, true net power, and total corneal refractive power readings (0.49 diopters [D] versus 0.70 D, 0.60 D, 0.64 D, and 0.76 D, respectively) (P < .001). Residual astigmatism after toric IOL implantation can be reduced by appropriate consideration of the posterior corneal astigmatism. Using methods that take into account the effect of the posterior cornea in toric IOL calculations is suggested. Drs. Assia and Kleinmann are consultants to Hanita Lenses, Israel. Dr. Abulafia received a speaker's fee from Haag-Streit AG. No other author has a financial or proprietary interest in any material or method mentioned.