Long-term refractive stability following combined astigmatic keratotomy and phakoemulsification

Double safe suture during cataract surgery on post radial keratotomy patients using clear corneal incisions

PURPOSE

the aim of this study is to find a safer surgical approach in cataract surgery on eyes previously treated with radial keratotomy using clear corneal incisions.

SETTING

Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Ophthalmology Clinic, University of Messina, Messina, Italy.

DESIGN

Prospective study.

METHODS

A prospective study was conducted on a group of 20 patients, 21 eyes with 16 RK incisions were evaluated for cataract phacoemulsification. Samples were divided into two groups: Group 1 underwent surgery with pre-operative one corneal stitch along radial keratotomy incisions near the main access site whereas Group 2 underwent modified surgery with two corneal stitches.

RESULTS

After surgery, visual acuity, corneal hysteresis and corneal strength was evaluated. In all cases, an increased visual acuity was observed. Group 1 showed an UCVA of logMAR 0.22 ± 0.14, while group 2 presented a logMAR of 0.1 ± 0.07. Data did not show a statistically significant difference in UCVA after surgery between the two groups (P = 0.133). Instead, a significant difference in corneal hysteresis (CH), respectively with values of 8.65 ± 1.6 mmHg in group 1 and 9.2 ± 1.8 in group 2 (P = 0.031), and a corneal resistance factor (CRF) with values of 7.87 ± 1.4 mmHg in the first group and 8.65 ± 1.6 mmHg in the second one (P = 0.039) was observed.

CONCLUSIONS

Double safe suture technique offers better stabilization of corneal structure during surgery in patients preventively treated with 16 incisions RK.

Five-Year Changes in Corneal Astigmatism After Combined Femtosecond-Assisted Phacoemulsification and Arcuate Keratotomy

PURPOSE

To investigate the long-term stability of corneal astigmatism after combined femtosecond (fs)-assisted phacoemulsification and arcuate keratotomy.

DESIGN

Retrospective, interventional case series.

METHODS

Surgery was performed using a Victus (Bausch & Lomb) platform. A single, 450-μm-deep arcuate keratotomy was paired at the 8-mm zone with the main phacoemulsification incision in the opposite meridian. The keratotomy incisions were not opened. Corneal astigmatism measurements obtained preoperatively and at 2 and 5 years postoperatively were analyzed using vector analysis.

RESULTS

A total of 44 eyes of 44 patients (mean age 66.0 ± 10.1 years) were included. The mean preoperative corneal astigmatism was 1.40 ± 0.66 diopters (D). This was reduced to 0.74 ± 0.54 D at 2 years and 0.70 ± 0.50 at 5 years postoperatively (P < .001). There were no statistically significant differences between postoperative corneal astigmatism at 2 years and at 5 years (P = .609). Both magnitude of error and absolute angle of error were comparable between the 2 postoperative time points (P > .805). At the end of 5 years, 65% of the eyes were within 15 degrees of the preoperative astigmatic meridian. Comparative analysis showed significantly higher surgically induced astigmatism, lower differences in vector and absolute angles of error for the eyes with preoperative with-the-rule (WTR) astigmatism than eyes with against-the-rule (ATR) astigmatism at 5 years (P < .004).

CONCLUSIONS

Our study showed the stability of femtosecond (fs)-assisted arcuate keratotomy was well-maintained over 5 years. There was a tendency of increasing overcorrection of preoperative WTR astigmatism and undercorrection of ATR astigmatism over time.

Effectiveness and confounding factors of penetrating astigmatic keratotomy in clinical practice: Case report

RATIONALE

Penetrating astigmatic keratotomy (penetrating AK) is a well-known method to correct corneal astigmatism but rarely be performed nowadays. This article reevaluated the clinical effectiveness and confounding factors of penetrating AK.

PATIENT CONCERNS

Penetrating AK has been introduced to serve as one alternative operation for astigmatism correction, and is thought to have the potential advantage of being more affordable and easy to perform. The purpose of our study is to evaluate the effectiveness and confounding factors of penetrating AK.

DIAGNOSES

The chart of 95 patients with corneal astigmatism (range: 0.75-3.25 diopters [D]) who received penetrating AK from January 2014 to December 2016 was collected. The corneal astigmatism were measured by an autokeratometer (Topcon KR8100PA topographer-autorefractor), and repeated with manual keratometer in low reproducibility cases.

INTERVENTIONS

All patients received penetrating AK by an experienced ophthalmologist (Dr. Gow-Lieng Tseng, MD, PHD) in the operation room. Among which, 66 patients received penetrating AK with phacoemulsification simultaneously (group A), whereas 29 patients received penetrating AK at least 3 months after phacoemulsification (group B). After excluding the patients combined with other procedures or lost followed up, 79 patients are remaining for analysis. The outcome was evaluated by net correction, the difference between preoperative corneal astigmatism (PCA) and residual corneal astigmatism (RCA). Two sample t tests and Pearson test were used for effectiveness evaluation. For confounding factors, multivariate linear regression was used for statistical analysis.

OUTCOMES

The mean preoperative and postoperative refractive cylinders were 1.97 ± 0.77 and 1.08 ± 0.64 D, respectively, in group A and 2.62 ± 1.05 and 1.51 ± 0.89 D in group B. There were no statistically significant differences in net correction between these two groups (0.9 ± 0.66 vs. 1.1 ± 0.69, P = .214). Higher PCA were associated with higher net correction in both group A (P = .002) and group B (P = .019). Compound myopic astigmatism caused less net correction than others only in group A (P = 0.031).

LESSONS

Penetrating AK is an accessible, affordable, and effective way to correct corneal astigmatism. The results of this procedure are comparable to modern methods in patients with low to moderate corneal astigmatism.

Cataract surgery on post radial keratotomy patients

This study aims to evaluate and to compare three different approaches of cataract surgery to patients with previous radial keratotomy (RK), and to analyze the mechanical properties of the cornea after cataract surgery. Three groups of patients, each one including 8 eyes of patients with 16 RK incisions. The first group includes eyes with the first cataract incision superiorly, the second group in the temporal area, the third group in temporal area and a precautionary stabilizing suture across the RK incision adjacent to the main tunnel. In the first group intraoperative dehiscence occurred in three eyes (37.5%): it required immediate application of a suture. In the second group dehiscence occurred intraoperatively in two radial scars (20%): it required immediate application of a suture. In the third group, no intraoperative dehiscences were observed. The stabilizing suture of the RK incision works safer, with a lower risk of dehiscences and less post-operative astigmatism.

Corneal Astigmatism and Aberrations After Combined Femtosecond-Assisted Phacoemulsification and Arcuate Keratotomy: Two-Year Results

PURPOSE

To investigate the stability of corneal astigmatism and higher-order aberrations after combined femtosecond-assisted phacoemulsification and arcuate keratotomy.

DESIGN

Retrospective, interventional case series.

METHODS

Surgery was performed using a VICTUS (Bausch & Lomb Inc, Dornach, Germany) platform. A single, 450-μm deep, arcuate keratotomy was paired at the 8-mm zone with the main phacoemulsification incision in the opposite meridian. The keratotomy incisions were not opened. Corneal astigmatism and higher-order aberration measurements obtained preoperatively and at 2 months and 2 years postoperatively were analyzed.

RESULTS

Fifty eyes of 50 patients (mean age 66.2 ± 10.5 years) were included. The mean preoperative corneal astigmatism was 1.35 ± 0.48 diopters (D). This was reduced to 0.67 ± 0.54 D at 2 months and 0.74 ± 0.53 D at 2 years postoperatively (P < .001). There was no statistically significant difference between postoperative corneal astigmatism over 2 years (P = .392). Both magnitude of error and absolute angle of error were comparable between the 2 postoperative time points (P > .283). At postoperative 2 months and 2 years, 72% and 70% of eyes were within 15 degrees of preoperative meridian of astigmatism, respectively. All wavefront measurements increased significantly at 2 months and 2 years (P < .007), except spherical aberration (P > .150). There was no significant difference in higher-order aberrations between 2 months and 2 years postoperatively (P > .486).

CONCLUSIONS

Our study showed the stability of femtosecond-assisted arcuate keratotomy. Further studies using other platforms and nomograms are needed to corroborate the findings of this study.

Spectacle Independence after Cataract Extraction in Post-Radial Keratotomy Patients Using Hybrid Monovision with ReSTOR(®) Multifocal and TECNIS(®) Monofocal Intraocular Lenses

Background

We report 2 patients who have undergone radial keratotomy (RK) preceding ReSTOR^® multifocal intraocular lens (IOL; Alcon, Fort Worth, Tex., USA) implantation in their nondominant eyes and TECNIS^® monofocal IOL (Abbott Medical Optics, Abbott Park, Ill., USA) in their dominant eyes.

Methods

Retrospective review of 2 patients who underwent hybrid monovision with ReSTOR^® multifocal and TECHNIS^® monofocal IOLs at the time of cataract surgery after a remote history of RK.

Results

Implantation of the ReSTOR^® multifocal and the TECHNIS^® monofocal IOLs was successful, with no reported adverse events. The patients were able to achieve spectacle freedom.

Conclusion

We report a novel technique for the management of post-RK patients to optimize their chances for spectacle independence.

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 Toric Intraocular Lenses and Arcuate Corneal Relaxing Incisions to Correct Moderate to High Astigmatism in Cataract Surgery

PURPOSE

To compare toric intraocular lens (IOL) implantation with arcuate corneal relaxing incisions for moderate to high corneal astigmatism during cataract surgery.

DESIGN

A retrospective comparison study.

METHODS

This 12-month single-surgeon study compared eyes with cataract and preexisting astigmatism of 1.75 diopters (D) or greater (range, 1.75-5.25 D) receiving corneal arcuate relaxing incisions or toric IOL implantation. Main outcome measures were visual acuity, refractive results, and IOL axis determination.

RESULTS

There were 45 and 20 eyes in the toric IOL and arcuate incision groups, respectively. Preoperative data were not significantly different between the 2 groups; the mean preoperative astigmatism was 2.16 ± 0.93 D in the toric IOL group and 2.41 ± 0.76 D in the incisional group. At 6 months postoperatively, the mean residual astigmatism was 0.75 and 1.33 D (P = 0.000), respectively; 82.2% and 44.4% of eyes were 1.00 D or less (P = 0.000), and 35.7% and 16.7% of eyes were 0.50 D or less (P = 0.000), respectively. Uncorrected distance visual acuity improved in both groups; eyes in the toric IOL group were more likely to be 20/30 or better (87% vs 29%, P = 0.008). Following surgery, all eyes had best corrected visual acuity of 20/40 or greater, and no eye lost a line of vision. The mean toric IOL rotation was 2.6 ± 1.7 degrees (range, 0-6 degrees).

CONCLUSIONS

Both toric IOLs and arcuate corneal incisions reduce moderate to high preexisting corneal astigmatism during cataract surgery; however, toric IOL implantation was more effective and predictable.