Femtosecond Laser-Assisted Capsulotomy Markings for the Alignment of Toric IOLs: A New Technique

Clinical outcomes and rotational stability after implantation of a monofocal toric intraocular lens with textured haptics in normal vs high axial lengths

PURPOSE

To compare the clinical outcomes and rotational stability after implantation of a toric intraocular lens (IOL) with textured haptics in eyes with normal vs high axial lengths (ALs).

SETTING

Nethradhama Superspeciality Eye Hospital, Bangalore, India.

DESIGN

2-arm, retrospective comparative study.

METHODS

This retrospective study included 114 eyes of 114 patients who underwent femtolaser cataract surgery followed by implantation of the HOYA Vivinex Toric monofocal IOL (Model XY1A-SP), of which 62 and 52 eyes belonged to normal (≤23.9 mm) and high (≥24 mm) AL groups, respectively. 1 week and 3 months postoperatively, clinical outcomes and rotational stability of the toric IOL was evaluated.

RESULTS

3 months postoperatively, % eyes achieving refractive astigmatism accuracy within ≤0.50 diopter, was 100% (n = 62) in the normal vs 94% (n = 49) in the high AL group. All eyes that is, 100% (n = 62) in the normal and 96.15% (n = 50) eyes in the high myopia group were <5 degrees of the intended axis. The mean change in postoperative rotation from 1 week to 3 months was 0.28 ± 0.09 degrees in the normal, and 0.30 ± 1.11 degrees in the high AL group ( P = .80). No significant correlation was observed between AL and white-to-white diameter with 1-week postoperative rotation values. No eye required repositioning of toric IOL for significant misalignment.

CONCLUSIONS

No significant differences were observed for clinical outcomes and postoperative rotational stability between eyes with normal and high ALs, suggesting excellent rotational stability of the Vivinex Toric IOL with textured haptics in all eyes, irrespective of the preoperative AL measurements.

Comparison of toric intraocular lens alignment between femtosecond laser-assisted capsular marking and digital marking

PURPOSE

To compare the accuracy of toric intraocular lens (IOL) alignment between femtosecond laser-assisted capsular marking and digital marking.

SETTING

Ruhr University Eye Clinic, Bochum, Germany.

DESIGN

Prospective clinical trial.

METHODS

In this study, 28 eyes of 23 patients, who underwent femtosecond laser-assisted cataract surgery with implantation of a toric IOL, were included. Intraoperatively, both femtosecond laser-assisted capsular marking and digital marking were applied simultaneously and compared in every case. The toric IOL was aligned to the capsular markings. Postoperatively, the axis of the capsular markings and toric IOL alignment was examined. Visual acuity and refractive outcomes were evaluated.

RESULTS

Both alignment methods were performed without intraoperative complications in all cases. 25 eyes were included in the final analysis. Misalignment was significantly lower with femtosecond laser-assisted capsular marking than with digital marking (1.71 ± 1.25 degrees vs 2.64 ± 1.70 degrees, P = .016). Deviation from the target axis of the toric IOL was 1.62 ± 1.24 degrees 4 to 6 weeks postoperatively. Postoperative uncorrected distance visual acuity was 0.14 ± 0.13 logMAR, and residual astigmatism was 0.3 ± 0.23 diopter (D) with an astigmatism ≤0.5 D in 93% of eyes.

CONCLUSIONS

Both methods showed excellent results for the alignment of toric IOLs. However, femtosecond laser-assisted capsular marking was significantly more precise than digital marking and showed good refractive results. In addition, capsular marking offers the possibility to avoid parallax error and evaluating postoperative IOL rotation.

Outcomes of toric IOL implantation guided by iris-registered femtosecond laser capsulotomy markings

PURPOSE

To assess the accuracy and stability of iris-registered femtosecond laser-assisted anterior capsule axis markings (compensating cyclotorsion) along with refractive and visual outcomes after toric IOL implantation.

METHODS

This prospective case series included eyes with visually significant cataracts and regular corneal astigmatism ranging from 1.25D to 4.0D, which received FLACS and toric IOL implantation, at The Eye Institute of West Florida, Largo, Florida, USA. Preoperative iris registration was used in conjunction with a femtosecond laser platform to create cyclotorsion corrected axis marks at the capsulotomy edge to facilitate toric IOL axial alignment. Patients were examined one, seven and thirty days after surgery to assess capsulotomy marks axis, toric IOL axis along with visual and refractive outcomes.

RESULTS

Eighteen eyes of 13 patients aged 74.35 ± 8.65 years were included. Mean pre-op CDVA was 0.24 ± 0.16 LogMAR, while mean post-op UDVA was 0.09 ± 0.09 LogMAR. Mean pre-op corneal astigmatism was 1.85 ± 0.41 D, decreasing to 0.24 ± 0.41 D of refractive astigmatism postoperatively (p < 0.001). The capsular toric axis markings were visible in 100% of eyes throughout the follow-up; the mean difference between intended capsulotomy mark axis and measured capsulotomy mark axis was 1.6°, 1.7° and 1.3 ^o at the 1, 7 and 30 day intervals (p > 0.05), respectively. No capsule-related or any other type of complications was noted.

CONCLUSIONS

Iris-registered femtosecond laser-assisted anterior capsule axis markings are safe and may be considered as an alternative option to the known axis marking techniques for toric IOL axial alignment at the time of cataract surgery.

Iris Registration Capsulotomy Marking Versus Manual Marking for Toric Intraocular Lens Alignment in Cataract Surgery

PURPOSE

To compare the accuracy of toric intraocular lens (IOL) alignment and visual outcomes using femtosecond laser-assisted capsulotomy marking (CM) versus conventional slit lamp-assisted manual marking (MM).

DESIGN

Prospective cohort study.

METHODS

A total of 57 patients who required cataract surgery and toric IOL implantation (Acrysof SN6AT3-T8) were assigned to the CM group (26 eyes) or the MM group (31 eyes). Uncorrected distant visual acuity (UCDVA), best-corrected distant visual acuity (BCDVA), residual astigmatism (RA), IOL misalignment, and modulation transfer function (area ratio [AR] value) were measured 1 and 3 months after surgery.

RESULTS

Postoperative UCDVA (logarithm of minimal angle of resolution [logMAR]) was significantly lower in the CM group than that in the MM group (P < .05). Postoperative RA and IOL misalignment were significantly lower in the CM group than that in the MM group (both P < .05). No significant difference between the groups was observed for BCDVA or AR value (both P > .05). UCDVA (logMAR) was positively correlated with RA (r = 0.339; P < .05) and IOL misalignment (r = 0.317; P < .05) and negatively correlated with the the AR value (r = -0.272; P < .05); RA was positively correlated with IOL misalignment (r = 0.405; P < .05).

CONCLUSIONS

The accuracy of the axis alignment was significantly higher in the CM group, which resulted in lower residual astigmatism and better visual outcomes.

Femtosecond laser-assisted refractive capsulorhexis - Precise capsulotomy with accurate toric intraocular lens alignment

Femtosecond laser-assisted cataract surgery with refractive capsulorhexis and toric intraocular lens (IOL) implantation was performed in 14 eyes with senile cataract and a preexisting regular corneal astigmatism of 1.5 D or more. Intraoperatively, the accuracy of the capsular rim marks was confirmed using the digital overlay of CALLISTO Eye and Z Align (Carl Zeiss Meditec, Germany). Postoperatively, the mean deviation from target axis of implantation was 2.07° ± 1.49°. Refractive capsulorhexis combines the advantages of a femtosecond laser capsulotomy with a one-step visual guide for intraoperative toric IOL alignment as well as postoperative assessment of rotational stability.