Intraoperative Arcuate Transverse Keratotomy With Phacoemulsification

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

PURPOSE

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

SETTING

Clinical research study.

DESIGN

Prospective randomized comparison study.

METHODS

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

RESULTS

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

CONCLUSION

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

Vector Analysis of Corneal Astigmatism After Combined Femtosecond-Assisted Phacoemulsification and Arcuate Keratotomy

PURPOSE

To evaluate the outcomes of femtosecond-assisted arcuate keratotomy combined with cataract surgery in eyes with low to moderate corneal astigmatism.

DESIGN

Retrospective, interventional case series.

METHODS

This study included patients who underwent combined femtosecond-assisted phacoemulsification and arcuate keratotomy between March 2013 and August 2013. Keratometric astigmatism was evaluated before and 2 months after the surgery. Vector analysis of the astigmatic changes was performed using the Alpins method.

RESULTS

Overall, 54 eyes of 54 patients (18 male and 36 female; mean age, 68.8 ± 11.4 years) were included. The mean preoperative (target-induced astigmatism) and postoperative astigmatism was 1.33 ± 0.57 diopters (D) and 0.87 ± 0.56 D, respectively (P < .001). The magnitude of error (difference between surgically induced and target-induced astigmatism) (-0.13 ± 0.68 D), as well as the correction index (ratio of surgically induced and target-induced astigmatism) (0.86 ± 0.52), demonstrated slight undercorrection. The angle of error was very close to 0, indicating no significant systematic error of misaligned treatment. However, the absolute angle of error showed a less favorable range (17.5 ± 19.2 degrees), suggesting variable factors such as healing or alignment at an individual level. There were no intraoperative or postoperative complications.

CONCLUSIONS

Combined phacoemulsification with arcuate keratotomy using femtosecond laser appears to be a relatively easy and safe means for management of low to moderate corneal astigmatism in cataract surgery candidates. Misalignment at an individual level can reduce its effectiveness. This issue remains to be elucidated in future studies.

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

PURPOSE

To compare toric intraocular lens (IOL) implantation and astigmatic keratotomy (AK) in correction of astigmatism during phacoemulsification.

SETTING

Tertiary care hospital.

DESIGN

Prospective randomized trial.

METHODS

Consecutive patients with visually significant cataract and moderate astigmatism (1.25 to 3.00 diopters [D]) were randomized into 2 groups. Temporal clear corneal 2.75 mm phacoemulsification with toric IOL implantation was performed in the toric IOL group and with 30-degree coupled AK at the 7.0 mm optic zone in the keratotomy group. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, keratometry, topography, central corneal thickness, and endothelial cell density were evaluated preoperatively and 1 day, 1 week, and 1 and 3 months postoperatively.

RESULTS

The study enrolled 34 eyes (34 patients), 17 in each group. There was no difference in UDVA or CDVA between the 2 groups at any follow-up visit. The mean preoperative and postoperative refractive cylinder was 2.00 D ± 0.49 (SD) and 0.33 ± 0.17 D, respectively, in the toric IOL group and 1.95 ± 0.47 D and 0.57 ± 0.41 D, respectively, in the keratotomy group (P=.10). The mean residual astigmatism at 3 months was 0.44 ± 1.89 @ 160 in the toric IOL group and 0.77 ± 1.92 @ 174 in the keratotomy group (P=.61). All eyes in the toric IOL group and 14 eyes (84%) in the keratotomy group achieved a residual refractive cylinder of 1.00 D or less (P=.17).

CONCLUSION

Toric IOL implantation was comparable to AK in eyes with moderate astigmatism having phacoemulsification.

Comparison of the keratometric corneal astigmatism and refractive astigmatism after phacoemulsification and foldable intraocular lens implantation

Here we aimed to define keratometric and refractive astigmatism in a series of patients who underwent phacoemulsification, using small corneal incision and implantation of foldable intraocular lenses. Furthermore, we compared keratometric astigmatism and refractive astigmatism of the patients both before and after surgery. We performed a follow-up study of patients with newly diagnosed cataract before and after phacoemulsification surgery. Eighty eyes from 78 patients with a mean age of 62.9 ± 12.03 (32-86) years were studied. Thirty-nine (48.8 %) were male and 41(51.2 %) were female. All subjects underwent 3.5 mm corneal incision with the temporal (75 patients; 94 %) or superior (5 patients; 6 %) approach. The patients were followed for a mean of 74.21 ± 71.25 (30-400) days. Patients had higher values of keratometric measurements after surgery compared to those before surgery [45.81 ± 0.11 (45.06-45.94) vs. 45.2 ± 0.20 (44.6-45.41)] (p < 0.001). There was no significant difference in the keratometric astigmatism, refractive astigmatism and keratometry axis pre- and postoperatively. The mean keratometric astigmatism was 0.9 ± 0.54 (0.00-4.00) diopters (D) preoperatively and 0.93 ± 0.45 (0.00-4.00) D postoperatively (p = 0.444). The keratometric axis was 97.7 ± 9.4 preoperatively and 115 ± 15.8 postoperatively (p = 0.185). Refractive astigmatism was 1.15 ± 0.77 (5-180) with the refractive axis of 89.7 ± 5.89 (5-180) degrees in the follow-up (p = 0.752). Ninety percent of the patients had <1.00 D difference in the keratometric and refractive astigmatism, postoperatively. In conclusion while there is no significant difference in postoperative keratometric and refractive astigmatism in most of the eyes, about 10 % show >1 D difference in these measurements.