Evaluation of Intraocular Lens Rotational Stability in a Multicenter Clinical Trial

Rotational stability of toric intraocular lenses by lens model and haptic design: systematic review and single-arm meta-analysis

Rotational stability is key for optimizing postoperative visual outcomes because even a small degree of rotation of a toric intraocular lens (IOL) from its target axis can result in a significant reduction in astigmatic correction. This systematic review and meta-analysis evaluated the rotational stability of toric IOLs of different lens models and haptic designs. All published studies and clinical trials that investigate postoperative rotation of toric IOLs were searched and evaluated. Quality of studies was assessed using the Methodological Index for Nonrandomized Studies scale. A single-arm meta-analysis was performed in R4.3.1 software with subgroup analysis performed based on lens model and haptic design. 51 published studies of 4863 eyes were included in the meta-analysis. The pooled mean absolute rotation of all toric IOLs was 2.36 degrees (95% CI, 2.08-2.64). Postoperative rotation is dependent on many aspects of lens material and design. Modern commercially available toric IOLs exhibit exceptional rotational stability.

Insights into the rotational stability of toric intraocular lens implantation: diagnostic approaches, influencing factors and intervention strategies

Toric intraocular lenses (IOLs) have been developed to enhance visual acuity impaired by cataracts and correct corneal astigmatism. However, residual astigmatism caused by postoperative rotation of the toric IOL is an important factor affecting visual quality after implantation. To decrease the rotation of the toric IOL, significant advancements have been made in understanding the characteristics of toric IOL rotation, the factors influencing its postoperative rotation, as well as the development of various measurement techniques and interventions to address this issue. It has been established that factors such as the patient's preoperative refractive status, biological parameters, surgical techniques, postoperative care, and long-term management significantly impact the rotational stability of the toric IOL. Clinicians should adopt a personalized approach that considers these factors to minimize the risk of toric IOL rotation and ensure optimal outcomes for each patient. This article reviews the influence of various factors on toric IOL rotational stability. It discusses new challenges that may be encountered to reduce and intervene with rotation after toric IOL implantation in the foreseeable future.

Repositioning Rates of Toric IOLs Implanted in Cataract Surgery Patients: A Retrospective Chart Review

Purpose

To determine the incidence of postoperative repositioning of toric intraocular lenses (IOLs) due to clinically significant rotation.

Patients and Methods

This study included consecutive cataract patients with pre-existing astigmatism who had undergone cataract surgery with toric IOL implantation by a single experienced surgeon. Case records of patients who were recommended to undergo toric IOL repositioning surgery due to clinically significant postoperative IOL rotation from the implanted axis were identified. The need for a secondary intervention to manage residual astigmatism was based upon postoperative residual astigmatic error ≥0.75 D, the patient's qualitative dissatisfaction with the level of postoperative distance vision, dilated post-op examination, and confirmation of the significant potential for astigmatism reduction.

Results

Case records of 993 eyes implanted with AcrySof toric (N = 362), Tecnis Toric I (N = 53), Tecnis Toric II (N = 308), or enVista Toric IOLs (N = 270) were included. Postoperative toric IOL repositioning was recommended in 16 eyes (1.6%). The repositioning rate was highest in the eyes implanted with Tecnis Toric I (5.7%), followed by AcrySof Toric (2.2%), enVista Toric IOLs (1.1%), and Tecnis Toric II (0.6%).

Conclusion

This real-world analysis of eyes implanted with toric IOLs revealed that the rate of surgical IOL repositioning due to clinically significant IOL rotation was lower than 2% for enVista and Tecnis Toric II IOLs. When needed and with appropriate planning, toric IOL repositioning can be very successful.

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

PURPOSE

To examine the rotational stability of a new toric intraocular lens (IOL), the TECNIS Eyhance Toric II, over a course of 3 months.

SETTING

Vienna Institute for Research in Ocular Surgery, Hanusch Hospital, Vienna, Austria.

DESIGN

Prospective unmasked single-center study.

METHODS

50 eyes of 50 patients with cataract and regular corneal astigmatism ≥0.75 diopters (D) were included. The TECNIS Eyhance Toric II IOL was implanted in 1 eye of each study patient. Images of the alignment axis of the IOL were taken intraoperatively, as well as at 1 hour, 1 week, and 3 months postoperatively. For the measurement of toric IOL rotation, images were superimposed on the basis of ocular landmarks. Uncorrected and corrected distance (4 m) and intermediate (66 cm) visual acuities were assessed at the 3-month visit.

RESULTS

There was no significant difference in the rotational position between the intraoperative and 3 month timepoints, with a mean rotation of 1.34 ± 1.46 degrees, in 27 examined eyes. ( P = 0.313). No patients had to undergo repositioning of the toric IOL. A significant reduction of refractive cylinder occurred from preoperatively 1.8 ± 1.1 to 0.40 ± 0.42 D at the 3-month visit ( P = .001; n = 43). The corrected distance visual acuity improved significantly from 0.28 ± 0.16 logMAR preoperatively to -0.01 ± 0.13 logMAR at 3 months postoperatively ( P = .001; n = 43).

CONCLUSIONS

The TECNIS Eyhance Toric II showed a good visual performance with no significant rotation over a course of 3 months and, therefore, an excellent rotational stability. The intraocular lens showed a good safety profile with no adverse events.

Post-Market Evaluation of Rotational Stability and Visual Performance of a New Toric Intraocular Lens with Frosted Haptics

PURPOSE

To evaluate 3-month rotational stability, and visual and refractive outcomes of a toric intraocular lens (IOL) with frosted haptics.

PATIENTS AND METHODS

A post-market, prospective, multi-center, single-arm, open-label study conducted at seven clinical sites in the United States. Two hundred and two eyes of 133 subjects with unilateral or bilateral cataracts and corneal astigmatism were implanted with the Tecnis Toric II IOL, Models ZCU150 to 600 (Johnson & Johnson Surgical Vision, Inc.). Lens axis misalignment/rotation, visual acuity, manifest refraction, and surgeon and patient satisfaction were evaluated 3 months postoperatively. Lens rotation was determined with operative and postoperative visit photographs and was analyzed by two independent masked analysts.

RESULTS

Mean absolute lens rotation was 0.82° ± 1.00° and 0.94° ± 0.71° at 1 day (n = 189 eyes) and 3 months (n = 185 eyes), respectively. Absolute lens rotation was ≤5° in 98.9% and 100% of eyes at 1 day and 3 months, respectively. At 3 months, postoperative monocular uncorrected and corrected distance visual acuities were 0.004 ± 0.115 LogMAR (20/20) and -0.066 ± 0.092 LogMAR (20/17), mean spherical equivalent was -0.25 D ± 0.35 D and residual refractive cylinder was +0.27 D ± 0.33 D. Surgeons were satisfied/very satisfied with overall clinical outcomes and rotational stability in 99% of eyes, and with uncorrected distance vision in 98.5% of eyes.

CONCLUSION

The study results demonstrate that the Tecnis Toric II IOL has excellent rotational stability with a high percentage of study eyes being within 5° of intended orientation. The study lens demonstrated excellent uncorrected distance visual acuity, reduction of cylinder, and exceptional patient and surgeon satisfaction.

Effects of Modified Haptics on Surgical Outcomes and Rotational Stability of Toric Intraocular Lens Implantation

PURPOSE

To assess the rotational stability of a new toric intraocular lens (IOL), TECNIS toric II (toric II), which is a modified version of the TECNIS toric IOL (toric I) with frosted haptics (Johnson & Johnson).

METHODS

A total of 101 eyes of 101 patients who had been treated with phacoemulsification and toric IOL implantation were included. Before and 1 day, 1 week, and 1 month after surgery, uncorrected (UDVA) and corrected (CDVA) distance visual acuity were measured. Preoperative corneal astigmatism and postoperative manifest refractive astigmatism at 1 day and 1 month were analyzed. At 1 day and 1 month postoperatively, the amount of IOL axis misalignment from the intended orientation, tilt, and decentration were measured using anterior segment optical coherence tomography.

RESULTS

Fifty-one eyes received the toric I IOL and 50 eyes received the toric II IOL. Toric I IOLs showed a significantly larger amount of axis misalignment than toric II IOLs at both 1 day (9.6 ± 7.6° vs 5.4 ± 4.8°, P = .003) and 1 month (9.1 ± 7.8° vs. 4.7 ± 4.2°, P = .003) postoperatively.The proportion of eyes with misalignment greater than 10° was significantly larger with toric I than toric II IOLs (P < .001). There were no significant differences between IOLs in the amount of residual astigmatism, UDVA, CDVA, and amount of tilt and decentration at 1 day and 1 month postoperatively.

CONCLUSIONS

The TECNIS toric II IOL with frosted haptics has significantly improved rotational stability compared to its previous model. [J Refract Surg. 2022;38(10):648-653.].

Reproducibility of the Magnitude of Lens Rotation Following Implantation of a Toric Intraocular Lens with Modified Haptics

Purpose

To evaluate the reproducibility of magnitude of postoperative IOL rotation following implantation of a toric intraocular lens (IOL) with modified haptics, in comparison with a Proof-of-Concept (POC) study of prototype IOLs featuring the same haptic design.

Patients and Methods

A post-market, prospective, multicenter, single-arm, open-label clinical study was conducted. TECNIS Toric II IOL (Johnson & Johnson Vision, Irvine, CA, USA, Models ZCU150 to 600) were implanted in 125 subjects and evaluated at 1-day and 1-week postoperatively. An objective photographic method was used to determine postoperative IOL rotation. Uncorrected distance visual acuity (UCDVA), postoperative astigmatism, and surgeon satisfaction were also assessed. Rotation data were compared to the POC study in which two prototype non-toric monofocal IOLs, one with the same haptic design as Model ZCU, were studied.

Results

Mean absolute rotation was 0.82° ± 1.0° and 0.84° ± 0.92°at 1-day and 1-week visits, respectively. The percentage of eyes with ≤5° of absolute rotation was 98.9% and 99.5% at the 1-day and 1-week visits, respectively. The magnitude of rotation was similar to the POC study prototype IOLs. At 1-week, mean monocular UCDVA was 0.026 ± 0.135 (~20/21) logMAR and mean residual manifest refractive cylinder was 0.30 D ± 0.35 D. The mean signed axis difference (postoperative minus operative) of the TECNIS Toric II IOL was 0.23° ± 1.27° at 1-day and −0.07° ± 1.25° at 1-week, indicating a clockwise drift. At 1-week, surgeons were very satisfied or satisfied with overall clinical outcomes and rotational stability in 98% of implanted eyes.

Conclusion

The TECNIS Toric II IOL, with frosted, squared haptics, demonstrated low magnitude of postoperative IOL rotation, excellent uncorrected distance vision, and minimal residual astigmatism. The POC study design was supported, demonstrating that prototype non-toric monofocal IOLs can predict clinical performance of toric IOLs with the same haptic design.

Toric intraocular lenses: Evidence‐based use

Uncorrected refractive astigmatism degrades visual acuity. Spherical intraocular lenses (IOLs) leave astigmatic errors resident in the cornea manifest in refractive astigmatism. Toric IOLs, correcting for this corneal astigmatism, contribute to spectacle‐free vision in the pseudophakic eye. This review provides information to assist surgeons in a rational choice of eyes suitable for toric IOL implantation, methods of IOL cylinder power calculation, surgical techniques for toric IOLs and management of complications. With appropriate application of this information, correction of visually detrimental astigmatism can be achieved routinely.