Clinical evaluation of three incision size-dependent phacoemulsification systems

Laboratory Analysis of Causative Factors for the Final Incision Size due to Intraocular Lens Injector Insertion

Purpose

In intraocular lens (IOL) implantation, insertion of the IOL injector enlarges the clear corneal incision. A larger incision size (IS) is associated with a higher risk for surgically induced astigmatism and endophthalmitis. The goal of this study was to determine which parameters most influence the final IS.

Design

Experimental study.

Subjects

A total of 126 cadaver porcine eyes were included in this study.

Methods

We analyzed 409 clear corneal incisions made with 126 injectors from 13 injector models. We noted the vertical diameter and the tip angulation for every model. The corneal thickness of each incision location was measured using Scheimpflug tomography. The IS was measured before and after injector insertion and described as preoperative and final ISs, respectively. During surgery, the insertion depth and incision length were documented. A mixed effects model was applied to analyze the influence of the parameters on the final IS.

Main Outcome Measures

Influence on the final IS.

Results

Increases in the vertical diameter of the injector tip, the preoperative IS and the insertion depth, and a reduction of incision length were all significantly associated with increased final IS (P < 0.05). The conditional Pseudo-R2-Measure was 0.92. The preoperative IS had the largest standardized estimated effect on the final IS, followed by the vertical diameter of the injector tip, insertion depth, and lastly, incision length. Neither corneal thickness nor the tip angle of the injector had a significant effect on the final IS (P > 0.05).

Conclusions

The IOL injector's vertical diameter should be as small as possible to ensure a minimal final IS. The injector's insertion depth may be minimized, and the incision length should be long enough to reduce the final IS. Further studies are needed to confirm the findings in human autopsy eyes and in clinical practice.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references in the Footnotes and Disclosures at the end of this article..

Enlargement of main corneal incision: clinical intraindividual comparison of two preloaded intraocular lens injectors

PURPOSE

To compare the enlargement of the clear corneal incision from IOL implantation with 2 different intraocular lens (IOL) injectors: the AutonoMe preloaded with the Clareon IOL and the Multisert preloaded with the Vivinex IOL.

SETTING

The David J. Apple Center for Vision Research, Department of Ophthalmology, University of Heidelberg, Heidelberg, Germany.

DESIGN

Prospective randomized clinical comparative study.

METHODS

96 eyes of 48 patients with cataract were intraindividually randomized to treatment with 1 of the 2 injectors. For Multisert eyes, the insert shield (IS) was used in the advanced position in 23 eyes. The initial incision was 2.2 mm, and intraoperative measurements of the incision size were made before and after IOL injection. 3 months postoperatively, keratometry and uncorrected (UDVA) and corrected (CDVA) distance visual acuities were assessed.

RESULTS

Results are reported for 96 eyes of 48 patients. The mean incision enlargement was 0.213 ± 0.068 mm in the Multisert with the IS group, 0.265 ± 0.055 mm in the fellow eyes (AutonoMe) ( P < .05), 0.272 ± 0.060 mm in Multisert eyes treated without the IS, and 0.296 ± 0.066 mm for the fellow eyes (AutonoMe) ( P > .05). The mean absolute surgically induced astigmatism was 0.42 ± 0.23 diopters (D), 0.50 ± 0.25 D, and 0.44 ± 0.18 D in the Multisert with the IS, Multisert without the IS, and AutonoMe group, respectively ( P > .05). The UDVA and CDVA were comparable in all groups.

CONCLUSIONS

The Multisert was associated with less wound enlargement than the AutonoMe. All groups had comparable functional outcomes. Therefore, the observed difference in incision enlargement may be of limited clinical relevance.

Corneal endothelial cell density loss following glaucoma surgery alone or in combination with cataract surgery: A systematic review and meta-analysis

TOPIC

Corneal endothelial cell density (ECD) loss following glaucoma surgery with or without cataract surgery.

CLINICAL RELEVANCE

Corneal ECD loss may occur due to intraoperative surgical trauma in glaucoma surgery or postoperatively with chronic endothelial cell trauma or irritation.

METHODS

Trabeculectomy, glaucoma filtration surgery or microinvasive glaucoma surgery in participants with ocular hypertension, primary and secondary open angle glaucoma, normal tension glaucoma and angle-closure glaucoma were included. Pediatric populations and participants with pre-existing corneal disease were excluded. Laser treatments and peripheral iridotomy were excluded. Electronic databases searched in December 2021 included MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov and The International Prospective Register of Systematic Reviews (PROSPERO), FDA PMA and FDA 510(k).

RESULTS

39 studies were included in quantitative synthesis. 12 months following suprachoroidal MIGS mean ECD loss was 282 cells/mm² (95% Confidence Interval (CI) 220 to 345; p <0.00001; Chi² = 0.06; I² = 0%; 2 studies; very low certainty). Mean ECD loss after Schlemm's canal implantable devices was 338 cells/mm² (95% CI 185 to 491; p<0.0001; Chi² = 0.08; I² = 0%; 2 studies; low certainty) at 12 months. When compared to phacoemulsification alone, Schlemm's canal implants combined with phacoemulsification showed statistically significant mean ECD reduction at 24 months; mean difference of ECD was -19% (95% CI -37% to -2%; p=0.03; Chi² = 3.04; I² = 34%; 3 studies; low certainty). Mean ECD loss was 64 cells/mm² (95% CI 21 to 107; p=0.004; Chi² = 4.55; I² = 0%; 6 studies; low certainty) following Schlemm's canal procedures (without implantable devices) at 12 months. At 12 months the mean ECD loss after trabeculectomy was 33 cells/mm² (95% CI -38 to 105, p=0.36, Chi² = 1.17; I² = 0%; moderate certainty). At 12 months mean ECD loss was 121 cells/mm² (95% CI 53 to 189; p=0.0005; Chi² = 3.00; I² = 0%; 5 studies; low certainty) after Express implantation. When compared to control fellow eye, aqueous shunt surgery reduced ECD by 5.75% (95% CI -0.93 to 12.43; p=0.09 Chi² = 1.32; I² = 0%; low certainty) and 8.11% ECD loss (95%CI 0.06 to 16.16 p=0.05; Chi²= 1.93; I²=48%) at 12 and 24 months, respectively.

CONCLUSIONS

Overall there is low certainty evidence to suggest that glaucoma surgery involving long-term implants has a greater extent of ECD loss than glaucoma filtration surgeries without the use of implants. The results of this review support long-term follow-up (beyond 36 months) to assess ECD loss and corneal decompensation following implantation of glaucoma drainage implants.

Incidence of Incision-Related Descemet Membrane Detachment Using Phacoemulsification With Trapezoid vs Conventional 2.2-mm Clear Corneal Incision: A Randomized Clinical Trial

Importance

The conventional 2.2-mm clear corneal incision is relatively narrow compared with the sleeves of Phaco handpieces, resulting in friction at the incision site and increased risk of incision-related Descemet membrane detachment (DMD). The modified 2.2-mm incision only enlarged internal width to 3.0 mm, forming a trapezoid incision shape, which may reduce the friction of surgical instruments and decrease the risk of incisional DMD.

Objective

To compare the incidence of incision-related DMD between eyes undergoing modified vs conventional 2.2-mm incision phacoemulsification for hard nuclear age-related cataract.

Design, Setting, and Participants

This double-masked, parallel randomized clinical trial was conducted from July 22, 2019, to January 22, 2020, at Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. The study included patients with age-related cataract and nuclear opalescence grade of 4.0 or greater based on the Lens Opacities Classification System III. Patients were enrolled in this study according to the following inclusion criteria: (1) age between 65 to 90 years; (2) pupil size of 6 mm or greater after dilation; (3) Lens Opacities Classification System III nuclear opalescence grade of 4.0 or more; and (4) corneal endothelial cell density greater than 1500 cells/mm2.

Interventions

Modified (enlarged internal width to 3.0 mm) or conventional 2.2-mm incision phacoemulsification with intraocular lens implantation.

Main Outcomes and Measures

Incidence of incision-related DMD at postoperative day 1.

Results

A total of 130 eyes of 130 patients were randomized into the conventional group (n = 65) or the modified group (n = 65). The mean (SD) age of participants was 74.5 (5.9) years and 74.3 (6.0) years in the conventional and modified groups, respectively. A total of 26 participants in the conventional group (40%) and 27 in the modified group (42%) were men. Compared with eyes in the conventional group, the incidence of DMD in eyes in the modified group was significantly lower at postoperative day 1 (difference, 26.15; 95% CI, 9.60-42.71; P = .003). The difference at postoperative day 7 was 16.92 (95% CI, 2.91-30.94; P = .02). The length of DMD (postoperative day 1: difference, 0.188; 95% CI, 0.075-0.301; P = .002) and maximal corneal thickness at incision site (postoperative day 1: difference, 0.032; 95% CI, 0.006-0.057; P = .02; postoperative day 7: difference, 0.019; 95% CI, 0.003-0.035; P = .02) were lower in the modified group, while visual quality parameter modulation transfer function (postoperative day 1: difference, -0.033; 95% CI, -0.064 to -0.001; P = .04) was higher. No difference was observed between the 2 groups in best-corrected visual acuity, central corneal endothelium loss, or surgically induced astigmatism at any follow-up time. There were no intraoperative complications in the 2 groups.

Conclusions and Relevance

These findings suggest that modified 2.2-mm trapezoid incision phacoemulsification reduces the incidence of DMD for hard nuclear age-related cataract at postoperative day 1 and might be considered in patients at high risk of incision-related DMD, although the clinical relevance cannot be determined with certainty from this trial.

Trial Registration

ClinicalTrials.gov identifier: NCT04014699.

Comparison between 0.1% Nepafenac and 1% Prednisolone Eye Drop in Postoperative Management Following Micro-incisional Cataract Surgery

Purpose

To compare the efficacy of 0.1% nepafenac and 1% prednisolone acetate eye drop in postoperative inflammation control in micro-incisional cataract surgery.

Methods

We conducted a prospective, randomized, comparative, single-blind study. All the patients underwent temporal 2.2-mm micro-incisional cataract surgery. They were randomized into two groups (group A and B). Group A received 0.1% nepafenac eye drops 4 times/day for 4 weeks and group B received 1% prednisolone acetate eye drops in tapering doses for 4 weeks after surgery. Both the groups received moxifloxacin 0.5% eye drops 4 times/day for 2 weeks. Patients were examined on 1st, 7th, and 30th postoperative days and parameters of postoperative inflammation were evaluated and noted at each visit.

Results

A total of 200 patients were enrolled in the study. However, five patients lost to follow up, group A had 97 and group B had 98 patients respectively. Results were statistically insignificant in terms of the difference in lid edema, conjunctival congestion, corneal edema, anterior chamber cells and flare between the two groups with p-values >0.05 for each parameter at each visit. However, the difference in mean central macular thickness between the groups was significant (205.713 ± 17.14 vs. 220.984 ± 32.83 in group A and B, respectively, p ≤ 0.001) at 1 month. Also, the mean pain score was significantly lower (p = 0.018) in the nepafenac group at day 7 of surgery.

Conclusions

Nepafenac is equally effective and non-inferior to prednisolone acetate in suppression and prevention of inflammation in postoperative period.

Real-Time Imaging of Incision-Related Descemet Membrane Detachment During Cataract Surgery

Question

When and how does incision-related Descemet membrane detachment (DMD) occur during cataract surgery?

Findings

In this case series of 133 patients with cataract, DMD was found in 125 cataract operations (94.0%) and occurred mostly during the phacoemulsification step (69 cases [55.2%]); DMD also increased throughout surgery.

Meaning

These findings suggest that incision-related DMD mainly occurs during the surgical steps in which the instruments create the greatest friction at the incision site and that severity is associated with the level of ultrasonic energy and length of time of phacoemulsification.

Importance

Incision-related Descemet membrane detachment (DMD) is a common complication of cataract surgery. Most postoperative severe DMD that leads to corneal decompensation originates from intraoperative incision-related DMD. It is important to determine the incidence, extent, and associated risk factors of intraoperative DMD at each step of surgery to help in formulating precise and effective prevention strategies.

Objectives

To investigate the intraoperative development of incision-site DMD associated with a 2.2-mm clear corneal incision during cataract surgery and to analyze its associated factors.

Design, Setting, and Participants

In this case series, consecutive, prospectively enrolled 133 patients with cataract 50 to 90 years of age (133 eyes) undergoing coaxial 2.2-mm clear corneal microincision phacoemulsification with intraocular lens (IOL) implantation between January 1 and March 31, 2019, at Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China, were studied.

Exposures

Coaxial 2.2-mm clear corneal microincision phacoemulsification with IOL implantation.

Main Outcomes and Measures

Real-time incidence and extent of intraoperative incision-related DMD at each step of surgery.

Results

Among 133 patients with cataracts (mean [SD] age, 72.3 [8.1] years; 77 [57.9%] female), DMD was encountered in 125 eyes (94.0%), occurring at the following steps: capsulorrhexis (2 [1.6%]), hydrodissection (7 [5.6%]), phacoemulsification (69 [55.2%]), irrigation-aspiration (44 [35.2%]), and IOL implantation (3 [2.4%]). The extent of DMD increased during the operation (mean [SD] difference between final and initial relative DMD length, 22.8% [1.4%]; 95% CI, 20.0-25.6; P < .001). Associations for the extent of DMD found in multivariate stepwise analyses included time of ultrasonography (β = 0.34; 95% CI, 0.17-0.50; P < .001), equivalent mean ultrasonic power (β = 87.8; 95% CI, 19.1-156.4; P = .01), and the presence of DMD at the anterior and posterior wound margins (coefficient = 16.7; 95% CI, 6.4-26.9; P = .002).

Conclusions and Relevance

The results of this case series suggest that friction of surgical instruments has the greatest association with incisional DMD. Decreasing ultrasonic energy and phacoemulsification time may reduce the severity of incisional DMD.

Comparison of visual outcomes after implantation of AtLisa tri 839 MP and Symfony intraocular lenses

Purpose

To compare visual outcomes after implantation of AtLisa tri 839 MP and Symfony intraocular lenses (IOLs).

Methods

All subjects underwent sequential bilateral cataract extraction with AtLisa tri 839 MP or Symfony IOL implantation. The design is prospective case series. Each group consists of 20 patients (40 eyes). At 1 year postoperatively, the following parameters were analysed: binocular uncorrected visual acuity (log MAR): for distance (UDVA) at 4 m, for intermediate distances (UIVA) at 60, 70, 80 cm and for near (UNVA) at 40 cm, defocus curve, mesopic and photopic contrast sensitivities (CSs), spectacle independence, visual function test questionnaire modified VFQ-25), photopic phenomena and postoperative complications.

Results

In the AtLisa tri 839 MP group, the mean binocular UNVA and UIVA were significantly better than in the Symfony group (UNVA: − 0.01 ± 0.04 vs. 0.21 ± 0.15; p = 0.000; 60 cm UIVA: − 0.01 ± 0.04 vs. 0.09 ± 0.09, p = 0.001; 70 cm UIVA − 0.05 ± 0.06 vs. 0.11 ± 0.08, p = 0.002; 80 cm UIVA − 0.01 ± 0.06 vs. 0.15 ± 0.08, p = 0.019). There were no significant between-group differences in the mean binocular UDVA and CS, with one exception: the mean binocular distance CS (18 cpd) under mesopic conditions was significantly better in the Symfony group than in the AtLisa tri 839 MP group (1.39 ± 0.22 vs. 1.17 ± 0.27; p = 0.015). The defocus curve analysis revealed significant between-group differences at vergences of 2.0 to − 4.0 D (p < 0.05), except for 2.0, 1.0, 0 and − 1.5. All subjects in AtLisa tri 839 MP group and 18 subjects (90%) in Symfony group were spectacle independent. Patients from both groups highly rated their overall vision quality in the VFQ-25 (1.67 ± 0.47 vs. 1.85 ± 0.5 in the Symfony and AtLisa tri 839 MP group, respectively, p = NS). The scores for daytime driving (1.00 ± 0.00 vs. 1.21 ± 0.36; p = 0.002), night driving (1.57 ± 0.55 vs. 2.13 ± 1.15; p = 0.027) and difficult situation driving (1.14 ± 0.31 vs. 1.53 ± 0.56; p = 0.049) were significantly better in the AtLisa tri 839 MP group than in the Symfony group. The incidence and perception level of halo and glare were significantly reduced (p = 0.00) in the Symfony group as compared to the AtLisa tri 839 MP group. The postoperative course was uneventful in all subjects.

Conclusions

Visual outcomes achieved with both IOLs are comparable. In both groups, 90% of patients achieved spectacle independence. Whereas the AtLisa tri 839 MP IOL implantation was associated with slightly better intermediate distance VA and significantly better near VA, photic phenomena were less perceived by patients with Symfony IOLs.

Effects of steep-axis incision on corneal curvature in one-handed phacoemulsification

AIM

To examine the effects of one-handed phacoemulsification with steep-axis incision on corneal curvature and analyze surgically induced astigmatism (SIA) on the true net power, anterior and posterior corneal surfaces.

METHODS

Patients with cataracts underwent one-handed phacoemulsification with a 2.4-mm steep-axis of clear corneal incision (CCI) based on true net power. CCI was created under the guidance of Verion. Central corneal thickness (CCT), keratometry readings of the true net power and anterior and posterior corneal surface were obtained using Pentacam. Biometry, such as axial length, anterior chamber depth (ACD) and white-to-white (WTW) were performed using Lenstar pre- and 3mo post-operatively.

RESULTS

The study evaluated 68 eyes of 65 patients. The mean age was 65.93±9.40y; CCT was 529.21±37.40 µm; WTW was 11.59±0.35 mm. Regarding true net power, keratometric value at the flattest corneal meridian for the 3-mm central zone (Ks) was significantly decreased postoperatively (P=0.031). Keratometric value at the steepest corneal meridian for the 3-mm central zone (Kf) was increased postoperatively (P>0.05). Astigmatism of true net power was 1.21±0.56 D preoperatively and significantly decreased to 1.02±0.58 D postoperatively (P=0.021). On the anterior corneal surface, no significant difference in Ks and Kf was noted pre- versus postoperatively. Anterior corneal astigmatism was 1.08±0.51 D preoperatively and significantly decreased to 0.87±0.46 D postoperatively (P=0.002). On the posterior corneal surface, Ks and Kf were significantly increased postoperatively (all P<0.05), and posterior corneal astigmatism also increased (P=0.008). The SIA values of true net power and the anterior and posterior corneal surfaces at 3mo postoperatively were 1.26±0.63 D (range: 0.11 to 2.80 D), 1.05±0.54 D (range: 0.23 to 2.40 D), and 0.21±0.17 D (range: 0.01 to 0.07 D), respectively.

CONCLUSION

One-handed phacoemulsification with steep-axis incision can effectively decrease astigmatism of true net power and anterior corneal astigmatism. In the same surgery, the difference in personal SIA potentially originated from a difference in personal corneal thickness and diameter, both CCT and WTW distance should always be measured preoperatively when planning steep-axis phacoemulsification.

Comparative Analysis of One-Handed and Two-Handed Coaxial Phacoemulsification with 2.4-mm Clear Corneal Incision

PURPOSE

To compare the efficiency and safety of one-handed and two-handed coaxial phacoemulsification Material and Methods: Patients with cataracts underwent one-handed (one-handed group) or two-handed coaxial phacoemulsification (two-handed group) with a 2.4-mm clear corneal incision. Intraoperative phaco parameters, total surgical time, postoperative visual acuity, surgically induced astigmatism (SIA), corneal volume (CV), central corneal thickness (CCT) and corneal endothelial cell counts/size were compared between the two groups.

RESULTS

Each group comprised 105 eyes. There were no significant differences in the intraoperative phaco parameters and total surgical time between the two groups (all p > 0.05). Visual outcomes were significantly better in the one-handed group than in the two-handed group 1 week postoperatively (all p< 0.05) but not 1 month postoperatively. There was no significant difference in SIA between the two groups 1 week (p = 0.695) or 1 month postoperatively (p = 0.772). CV, CCT and endothelial cell loss were significantly lower in the one-handed group than in the two-handed group 1 week postoperatively (CV: p = 0.004; CCT: p = 0.046; endothelial cell loss: p = 0.021), but the above differences were absent 1 month postoperatively except for endothelial cell loss (endothelial cell loss: p = 0.038).

CONCLUSIONS

Both one-handed and two-handed coaxial phacoemulsification were effective and safe surgical techniques. However, the one-handed technique had the advantages of less trauma to the cornea and better early clinical outcomes than the two-handed technique for cataract patients within nuclear opalescence (NO) 3 grade ≤ 3.

Optical quality and visual performance after cataract surgery with biaxial microincision intraocular lens implantation

PURPOSE

To evaluate the time course of the optical quality and visual performance with a microincision monofocal intraocular lens (Incise).

SETTING

Hospital Torrecárdenas, Almería, Spain.

DESIGN

Prospective study.

METHODS

The visual and refractive outcomes were evaluated in eyes with the microincision IOL preoperatively and 1, 3, and 6 months postoperatively. The modulation transfer function (MTF) cutoff frequency, Strehl ratio, and objective scatter index (OSI) were used to measure optical quality. The contrast sensitivity function (CSF) and the visual disturbance index characterized visual performance.

RESULTS

In the 32 study eyes, the mean values preoperatively and 6 months postoperatively, respectively, were MTF cutoff frequency (11.40 cycles per degree [cpd] ± 8.39 [SD] and 23.33 ± 11.68 cpd; P < .001), Strehl ratio (0.078 ± 0.32 and 0.15 ± 0.07; P < .05), and OSI (7.44 ± 3.25 and 1.57 ± 0.26; P < .001). At each spatial frequency, the CSF significantly differed between preoperatively and postoperatively (P < .001). The mean visual disturbance index changed from 0.70 ± 0.28 to 0.31 ± 0.17 (P < .001). For all parameters studied, statistically significant differences were found between the preoperative and postoperatively values, with no differences between the results 1, 3, and 6 months after surgery (P > .05).

CONCLUSIONS

Biaxial microincision cataract surgery provided optimum clinical outcomes. The optical quality and visual performance improved significantly 1 month after surgery, with the results remaining stable at 6 months. The postoperative visual function was similar to that in subjects of the same age with healthy eyes.

FINANCIAL DISCLOSURE

None of the authors has a financial or proprietary interest in any material or method mentioned.

Comparison of variations in cornea after one-handed and two-handed coaxial phacoemulsification

Purpose

To compare corneal variations in patients undergoing one-handed and two-handed coaxial phacoemulsification.

Setting

Eye Institute, Affiliated Hospital of Nantong University, Nantong, China.

Design

Prospective consecutive nonrandomized comparative cohort study.

Methods

Patients with cataracts were subject to one-handed (one-handed group) or two-handed coaxial phacoemulsification (two-handed group). Intraoperative phaco parameters and postoperative outcomes, such as visual acuity, surgically induced astigmatism (SIA), corneal volume, central corneal thickness, and corneal endothelial cell counts/size were compared.

Results

No significant differences in the intraoperative phaco parameters were noted between the 2 groups. At postoperative week 1, visual outcomes were significantly improved in the one-handed compared with the two-handed group (all P<0.05). Corneal volume, central corneal thickness, and average cell size were significantly decreased in the one-handed group compared with two-handed group (all P<0.05), but the aforementioned differences were ameliorated at 1 month and 3 months postoperatively. Endothelial cell loss was significantly decreased in the one-handed group compared with the two-handed group at any follow-up point (all P<0.05). No significant differences in SIA on the anterior surface were noted between the 2 groups. SIA on the posterior surface was significantly decreased in the one-handed group compared with the two-handed group at 1 week postoperatively (P=0.043) but not at 1 month and 3 months postoperatively.

Conclusion

One-handed phacoemulsification has the advantages of less trauma to the cornea and better early visual outcomes compared with the two-handed technique.

Surgically induced astigmatism following trabeculectomy

PURPOSE

Surgically induced astigmatism (SIA) has attracted much interest in recent times because changes in corneal astigmatism can lead to decreased uncorrected visual acuity and patient discomfort. This study aimed to evaluate SIA and to identify factors correlated therewith after trabeculectomy.

METHODS

We retrospectively reviewed medical charts of patients who were treated with trabeculectomy at 120° meridian (superotemporal area on right eye and superonasal area on left eye) by the same surgeon. Preoperative keratometric data were compared with data collected from 2 months to 12 months postoperatively. SIA was evaluated using Naeser's polar value analysis.

RESULTS

Using Naeser's method, ΔKP(120) was calculated as 0.7 ± 0.7 (0.82@104°), which indicates a with-the-rule change. After surgery, the combined mean polar values changed significantly (Hotelling T² = 22.47; p < 0.001). Multivariate analysis of variance indicated that postoperative intraocular pressure and location of surgery were independent factors that were significantly associated with SIA (p = 0.002 and 0.03, respectively).

CONCLUSIONS

Trabeculectomy at the 120° meridian was not astigmatically neutral. In addition, the SIA after trabeculectomy appears to be greater in eyes with low postoperative intraocular pressure and a superonasal surgical wound rather than a superotemporal wound.

Surgically induced astigmatism after phacoemulsification by temporal clear corneal and superior clear corneal approach: a comparison

INTRODUCTION

Cataract surgery has undergone various advances since it was evolved from ancient couching to the modern phacoemulsification cataract surgery. Surgically induced astigmatism (SIA) remains one of the most common complications. The introduction of sutureless clear corneal incision has gained increasing popularity worldwide because it offers several advantages over the traditional sutured limbal incision and scleral tunnel. A clear corneal incision has the benefit of being bloodless and having an easy approach, but SIA is still a concern.

PURPOSE

In this study, we evaluated the SIA in clear corneal incisions with temporal approach and superior approach phacoemulsification. Comparisons between the two incisions were done using keratometric readings of preoperative and postoperative refractive status.

METHODOLOGY

It was a hospital-based prospective interventional comparative randomized control trial of 261 patients conducted in a rural-based tertiary care center from September 2012 to August 2014. The visual acuity and detailed anterior segment and posterior segment examinations were done and the cataract was graded according to Lens Opacification Classification System II. Patients were divided for phacoemulsification into two groups, group A and group B, who underwent temporal and superior clear corneal approach, respectively. The patients were followed up on day 1, 7, 30, and 90 postoperatively. The parameters recorded were uncorrected visual acuity, best-corrected visual acuity, slit lamp examination, and keratometry. The mean difference of SIA between 30th and 90th day was statistically evaluated using paired t-test, and all the analyses were performed using SPSS 18.0 (SPSS Inc.) software.

RESULTS

The mean postoperative SIA in group A was 0.998 D on the 30th day, which reduced to 0.768 D after 90 days, and in group B the SIA after 30 days was 1.651 D, whereas it reduced to 1.293 D after 90 days.

CONCLUSION

Temporal clear corneal incision is evidently better than superior clear corneal incision as far as SIA is concerned.

Comparison of efficacy between coaxial microincision and standard-incision phacoemulsification in patients with age-related cataracts: a meta-analysis

BACKGROUND

Incision size plays a critical role in the efficacy of cataract surgery, but the available evidence on ideal incision size is inconsistent. In this study, we conducted a meta-analysis to evaluate the efficacy of coaxial microincisional phacoemulsification surgery (MICS) compared with that of standard-incision phacoemulsification surgery (SICS) in patients with age-related cataracts.

METHODS

The Cochrane Library (Wiley Online Library), PubMed, Medline, National Knowledge Infrastructure (CNKI), and VIP databases were searched to identify reports of clinical randomized controlled trials (RCTs) comparing MICS to SICS for the treatment of age-related cataracts. The outcomes of interest included surgically induced astigmatism (SIA), effective phacoemulsification time (EPT), central corneal thickness (CCT), endothelial cell count (ECC), endothelial cell count loss (ECC Loss %), and average ultrasonic energy (AVE).

RESULTS

Eleven RCT studies were included in this meta-analysis. No statistically significant differences were observed in EPT (Z = 1.29, P > 0.05), CCT (1 day: Z = 1.37, P > 0.05; 7 days: Z = 0.75, P > 0.05; 30 days: Z = 0.38, P > 0.05; 90 days: Z = 0.29, P > 0.05), ECC (7 days: Z = 1.13, P > 0.05; 30 days: Z = 1.42, P > 0.05) or ECC Loss % (7 days: Z = 0.24, P > 0.05; 30 days: Z = 0.06, P > 0.05; 90 days: Z = 0.10, P > 0.05) between MICS and SICS. However, statistically significant differences were found in AVE (Z = 4.19, P < 0.0001) and SIA (1 day: Z = 10.33, P < 0.00001; 7 days: Z = 10.71, P < 0.00001; 30 days: Z = 10.95, P < 0.00001; 90 days: Z = 2.21,- P < 0.01) between MICS and SICS.

CONCLUSION

Compared with SICS, MICS can reduce short-term and long-term SIA, but it does not differ in safety outcomes or in the time required for surgery.

Different-sized incisions for phacoemulsification in age-related cataract

BACKGROUND

Age-related cataract is the principal cause of blindness and visual impairment in the world. Phacoemulsification is the main surgical procedure used to treat cataract. The comparative effectiveness and safety of different-sized incisions for phacoemulsification has not been determined.

OBJECTIVES

The aim of this systematic review was to assess the effectiveness and safety of smaller versus larger incisions for phacoemulsification in age-related cataract. The primary outcome of this review was surgically induced astigmatism at three months after surgery.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 10), MEDLINE Ovid (1946 to 28 October 2016), Embase Ovid (1947 to 28 October 2016), PubMed (1948 to 28 October 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 28 October 2016), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com; last searched 13 May 2013), ClinicalTrials.gov (www.clinicaltrials.gov; searched 28 October 2016), and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp; searched 28 October 2016). We did not use any date or language restrictions in the electronic searches for trials.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing different-sized incisions in people with age-related cataract undergoing phacoemulsification.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 26 RCTs with a total of 2737 participants (3120 eyes). These trials were conducted in Bosnia and Herzegovina, China, France, India, Italy, Korea, Spain, Switzerland, and Turkey. Half of the 26 trials were conducted in China. We judged all trials as mostly at unclear to low risk of bias. The included RCTs compared four different-sized incisions:<= 1.5 mm, 1.8 mm, 2.2 mm, and approximately 3.0 mm. These incisions were performed using three different techniques: coaxial and biaxial microincision phacoemulsification (C-MICS and B-MICS) and standard phacoemulsification. Not all studies provided data in a form that could be included in this review. Five studies had three arms.Fifteen trials compared C-MICS (2.2 mm) with standard phacoemulsification (about 3.0 mm). Very low-certainty evidence suggested less surgically induced astigmatism in the C-MICS group at three months compared with standard phacoemulsification (mean difference (MD) -0.19 diopters (D), 95% confidence interval (CI) -0.30 to -0.09; 996 eyes; 8 RCTs). There was low-certainty evidence that both groups achieved similar best-corrected visual acuity (MD 0.00 logMAR, 95% CI -0.02 to 0.02; 242 eyes; 3 RCTs). There was low-certainty evidence of little or no difference in endothelial cell loss and central corneal thickness comparing C-MICS with standard phacoemulsification (MD -7.23 cells/mm², 95% CI -78.66 to 64.20; 596 eyes; 4 RCTs) and (MD -0.68 μm, 95% CI -3.26 to 1.90; 487 eyes; 5 RCTs).Nine trials compared C-MICS (1.8 mm) with standard phacoemulsification (about 3.0 mm). Very low-certainty evidence suggested less astigmatism at three months in the C-MICS group compared with standard phacoemulsification group (MD -0.23 D, 95% CI -0.34 to -0.13; 561 eyes; 5 RCTs). Low-certainty evidence suggested little or no difference in best-corrected visual acuity, endothelial cell loss, and central corneal thickness in the two groups at three months (MD -0.02 logMAR, 95% CI -0.03 to -0.00; 192 eyes; 3 RCTs), (MD 7.56 cells/mm², 95% CI -67.65 to 82.77; 380 eyes; 5 RCTs), and (MD -1.52 μm, 95% CI -6.29 to 3.25; 245 eyes; 3 RCTs).Six studies compared C-MICS (1.8 mm) with C-MICS (2.2 mm). There was low-certainty evidence that astigmatism, visual acuity, and central corneal thickness were similar in the two groups at three months (MD 0.04 D, 95% CI -0.09 to 0.16; 259 eyes; 3 RCTs), (MD 0.01 logMAR, 95% CI -0.01 to 0.04; 200 eyes; 3 RCTs), and (MD 0.45 μm, 95% CI -2.70 to 3.60; 100 eyes; 1 RCT). Very low-certainty evidence suggested higher endothelial cell loss in the 1.8 mm group (MD 213.00 cells/mm², 95% CI 11.15 to 414.85; 70 eyes; 1 RCT).Four studies compared B-MICS (<= 1.5 mm) with standard phacoemulsification (about 3.0 mm). Astigmatism was similar in the two groups at three months (MD -0.01 D, 95% CI -0.03 to 0.01; 368 eyes; 2 RCTs; moderate-certainty evidence). There was low-certainty evidence on visual acuity, suggesting little or no difference between the two groups (MD -0.02 logMAR, 95% CI -0.04 to -0.00; 464 eyes; 3 RCTs). Low-certainty evidence on endothelial cell loss and central corneal thickness also suggested little or no difference between the two groups (MD 55.83 cells/mm², 95% CI -34.93 to 146.59; 280 eyes; 1 RCT) and (MD 0.10 μm, 95% CI -14.04 to 14.24; 90 eyes; 1 RCT).None of the trials reported on quality of life. One trial reported that no participants experienced endophthalmitis or posterior capsule rupture; they also reported little or no difference between incision groups regarding corneal edema (risk ratio 1.02, 95% CI 0.40 to 2.63; 362 eyes).

AUTHORS' CONCLUSIONS

Phacoemulsification with smaller incisions was not consistently associated with less surgically induced astigmatism compared with phacoemulsification with larger incisions. Coaxial microincision phacoemulsification may be associated with less astigmatism than standard phacoemulsification, but the difference was small, in the order of 0.2 D, and the evidence was uncertain. Safety outcomes and quality of life were not adequately reported; these should be addressed in future studies.

Change in Anterior and Posterior Curvature After Cataract Surgery

PURPOSE

To analyze the change in anterior and posterior corneal curvature after cataract surgery using a Placido-dual rotating Scheimpflug device.

METHODS

In a prospective cross-sectional study, corneal curvature was measured using the Galilei G4 device (Ziemer Ophthalmic Systems, Port, Switzerland) preoperatively and 1 week and 1, 3, and 6 months after cataract surgery with a temporal limbal self-sealing 2.2-mm incision. The surgically induced astigmatism (SIA) was determined on the anterior and posterior surfaces.

RESULTS

Fifty-nine patients (68 eyes) were assessed. Based on the anterior corneal surface, 16 (23.5%) eyes had a vertically steep meridian (with-the-rule [WTR] astigmatism), 32 (47.1%) had a horizontally steep meridian (against-the-rule [ATR] astigmatism), and 20 (29.4%) had oblique astigmatism. Based on the posterior corneal surface, 2 (2.9%) eyes had a horizontally steep meridian (ATR astigmatism), 62 (91.2%) had a vertically steep meridian (WTR astigmatism), and 4 (5.9%) had oblique astigmatism. SIA of the anterior and posterior corneal surfaces was 0.61 ± 0.33 and 0.20 ± 0.17 diopters (D), respectively. However, there was no significant difference between the preoperative and the 6-month postoperative data in the Jackson coefficient orthogonal coordinate system for the anterior and posterior corneal surfaces. SIA of WTR astigmatism of the posterior cornea was 0.19 ± 0.16 D at 6 months. Sixty-one of 62 eyes with WTR astigmatism in the posterior corneal surface still showed WTR astigmatism after cataract surgery.

CONCLUSIONS

The tendency of SIA of the posterior cornea may not be uniform, but type of posterior corneal astigmatism did not change in most cases after the 2.2-mm temporal limbal incision cataract surgery. [J Refract Surg. 2016;32(11):754-759.].

Torsional and flattening effect on corneal astigmatism after cataract surgery: a retrospective analysis

Background

To evaluate the torsional and flattening effect of steep meridian incisions and influence of posterior corneal astigmatism (PCA) on total corneal astigmatism (TCA) after cataract surgery.

Methods

One hundred thirty-two eyes underwent cataract surgery with steep meridian 2.2 mm microcoaxial and 2.85 mm conventional clear corneal incisions. Eyes were divided into with-the-rule (WTR) astigmatism and against-the-rule (ATR) astigmatism groups depending on the steeper meridian and measured with autokeratorefractor and Pentacam® before surgery, at 1 day, 1 week, 1 and 2 months postoperatively. Polar vector analysis was used to evaluate torsional effect of steep meridian incisions.

Results

A decrease in astigmatic polar value (AKP) (+0) was observed in both keratometric and total astigmatism (TA) after 1 and 2 months, although the decrease was only statistically significant in TA (p < 0.05). The AKP(+45) was more significant in the conventional group than the microcoaxial group at 2 months postoperatively (p < 0.05, respectively). There was a significant correlation between corneal thickness of the superior quadrant and PCA in the WTR group (p = 0.028). In eyes with anterior corneal astigmatism smaller than 0.55D of WTR astigmatism and PCA greater than 0.35D of WTR astigmatism showed greater shifting of steep axis and also increment of refractive cylinder powers.

Conclusions

In eyes with superior corneal thickness greater than 714.5 μm and PCA greater than 0.35D of WTR astigmatism, steep meridian incision may cause a significant torsional effect and off-steep meridian change, contributing to an increment of postoperative residual manifest astigmatism after cataract surgery.

Comparative analysis of coaxial phacoemulsification with 2.2- and 2.8-mm clear corneal incisions

PURPOSE

To compare the intraoperative efficiency and postoperative visual outcome of coaxial phacoemulsification using 2.2- and 2.8-mm clear corneal incision coaxial phacoemulsification.

SETTING

The study was conducted at Vardhaman Mahavir Medical College and Safdarjung Hospital, New Delhi which is a tertiary health care centre.

STUDY DESIGN

This is a prospective, randomized, comparative interventional study.

MATERIALS AND METHODS

A total of 140 eyes of patients undergoing cataract surgery were enrolled according to the inclusion-exclusion criteria and randomly divided in two groups of 70 such that Group I-Patients underwent phacoemulsification through 2.8-mm clear corneal incision. Group II-Patients underwent phacoemulsification through 2.2-mm clear corneal incision.Postoperative assessment was done at 1 day, 1 and 6 weeks to note best-corrected visual acuity (BCVA), ophthalmic examination, corneal topography, central corneal thickness and corneal endothelial cell count.

STATISTICS

1. Quantitative variables were compared using Mann-Whitney test and Wilcoxon ranked-sum test. 2. Qualitative variables were compared using Fisher's exact test. p value of <0.05 was considered statistically significant.

RESULTS

There is steady trend in decrease in postoperative astigmatism with time, more so in 2.8 mm group; however, differences were not found to be statistically significant. 2.2 mm group had larger increase in CCT and ECC compared to 2.8 mm group which was not statistically significant (p = 0.296).

CONCLUSION

Reducing the incision size from 2.8 to 2.2 mm does not result in any significant reduction in the amount of surgically induced astigmatism. Also, both the incision sizes have similar intraoperative efficacy when compared in terms of postoperative decrease in corneal endothelial cell count and increase in central corneal thickness.

A comparable study of clinical and optical outcomes after 1.8, 2.0 mm microcoaxial and 3.0 mm coaxial cataract surgery

AIM

To evaluate the clinical and optical outcomes after clear corneal incision cataract surgery (CICS) with three different incision sizes (1.8, 2.0 and 3.0 mm).

METHODS

Eyes of 150 patients with age-related cataract scheduled for coaxial cataract surgery were randomized to three groups: 1.8, 2.0, or 3.0 mm CICS. Intraoperative data and postoperative outcomes including surgically induced astigmatism (SIA), the corneal incision thickness, wavefront aberrations and modulation transfer function (MTF) of cornea were obtained.

RESULTS

There were no significant differences among the three groups in demographic characteristics and intraoperative outcome. The 1.8 and 2.0 mm microincisions showed more satisfactory clinical outcomes than the 3.0 mm incision. The 1.8 mm incision showed significantly less SIA than the 2.0 mm incision until postoperative 1mo (P<0.05), but the difference was only 0.14-0.18 D. Combined with less increased incision thickness only at postoperative 1d (P=0.013), the 1.8 mm incision presented better uncorrected distance visual acuity (UCDVA) than the 2.0 mm incision only at 1d postoperatively (P=0.008). For higher-order aberrations and other Zernike coefficients, there were no significant differences between the 1.8 mm group and 2.0 mm group (P>0.05).

CONCLUSION

Converting from 3.0 mm CICS to 1.8 or 2.0 mm CICS result in better clinical and optical outcomes. However, when incision is 1.8 mm, the benefits from further reduction in size compared with 2.0 mm are limited. The necessity to reduce the incision size is to be deliberated.

Coaxial Microincision Cataract Surgery versus Standard Coaxial Small-Incision Cataract Surgery: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

We conducted this meta-analysis to compare the outcomes of coaxial microincision cataract surgery (C-MICS) and standard coaxial small incision cataract surgery (C-SICS).

METHODS

The outcomes of randomized controlled trials (RCTs) reporting C-MICS and C-SICS were collected from PubMed, Web of Science, and The Cochrane Library in May 2015. The final meta-analysis was conducted on the following intraoperative and postoperative outcomes: ultrasound time (UST), effective phacoemulsification time (EPT), balanced salt solution use (BSS use), cumulative dissipated energy (CDE), mean surgery time, endothelial cell loss percentage (ECL%), best corrected visual acuity (BCVA), increased central corneal thickness (CCT), laser flare photometry values and surgically induced astigmatism (SIA).

RESULTS

A total of 15 RCTs, involving 1136 eyes, were included in the final meta-analysis. No significant between-group differences were detected in EPT, BSS use, CDE, BCVA, laser flare photometry values or increased CCT. However, the C-MICS group showed less SIA (at postoperative day 7: p<0.01; at postoperative day 30 or more: p<0.01) and greater ECL% (at postoperative day 60 or more: p<0.01), whereas the C-SICS group required a shorter UST (p<0.01).

CONCLUSIONS

The present meta-analysis suggested that the C-MICS technique was more advantageous than C-SICS in terms of SIA, but C-MICS required a longer UST and induced a higher ECL%. Further studies should be done to confirm our results.

Novel approach for phacoemulsification during combined phacovitrectomy

Purpose

To evaluate the safety and efficacy of surgeon’s superior sitting position during temporal clear corneal incision (TCCI) phacoemulsification, with a 90° working angle, during combined phacovitrectomy.

Methods

Prospective interventional case series were performed on 65 eyes of 63 patients. TCCI phacoemulsification was done in all cases (whether right or left eyes), while the surgeon was sitting superiorly to the operating table.

Outcome measures included

Shift in sitting position, keratometric astigmatism, surgically induced astigmatism, posterior capsule integrity, and intraocular lens centration.

Results

Phacoemulsification was performed completely in all cases (100%). Shift in position to temporal sitting position happened in two cases (3%). The keratometric astigmatism showed mean changes of 1.09 D (0.25–3.75 D) to 0.84 D (0.00–3.25 D) at 1 month, which remained stable at 6 months; 0.84 D (0.16–3.21 D). The surgically induced astigmatism was 0.25 DC (−0.50 to 1.0 DC) at 1 month, which stayed stable at 6 months; 0.25 D (−0.63 D to 0.98 D). Posterior capsular rupture occurred in one case (the second case) (1.5%). The intraocular lens was centered in all cases (100%).

Conclusion

Superior sitting TCCI phacoemulsification, with a wide working angle, during combined phacovitrectomy proved safe and easy, without the burden of changing and disrupting the operative setting. The anatomical and optical outcomes were acceptable.

Corneal injection track: an unusual complication of intraocular lens implantation and review

Phacoemulsification is the main gold standard for cataract operation in the developed world together with foldable intraocular lens (IOL) implantation by injection, allowing for stable wound construction and less postoperative astigmatism. It is a safe procedure with high success rate with the advancement in machines, improvement of IOL injection systems and further maturation of surgeons' techniques. Despite the large number of operations performed every day, foldable IOL injection leading to an intra-stromal corneal track is a very rare complication. We report a case of this unusual finding in a 70-year-old gentleman who has undergone cataract operation in November 2011 in our hospital and will review on the complications related to foldable IOL injection.

Polynomial curve fitting of the corneal profile in 2.2-mm corneal incision phacoemulsification

PURPOSE

To model incisional axis and perpendicular corneal profile pattern changes in 2.2-mm corneal incision phacoemulsification.

METHODS

Sixty-seven eyes of 67 patients were included in this prospective, interventional, before-after paired design study. Power vector components were obtained from keratometry (IOLMaster; Carl Zeiss Meditec, Göttingen, Germany) and topography corneal height data with the Pentacam HR (Oculus Optikgeräte, Wetzlar, Germany) preoperatively and at 6 months postoperatively. Second- to sixth-order curve fitting polynomial functions of the corneal profile in the incisional and perpendicular axes were created using Matlab (The Mathworks, Inc., Natick, MA). Multivariate regression analysis was run to study the influence of potential predictors. Correlation of changes in corneal elevation and corneal radius with astigmatic parameters was also obtained.

RESULTS

Significant changes occurred only in the J(0) (P = .004) and M (P = .001) parameters. R(2) was high with all of the fitted polynomials (0.98 to 0.99) and although the smallest root mean square error was obtained with sixth-degree polynomials (0.63 to 1.13), they were more badly conditioned and redundant than quadratic polynomials. Corneal flattening changes were obtained on axis, which was the most frequent pattern (n = 52, 77%), but were significantly larger in the incisional side than the non-incisional side (P = .001) and only coupled with perpendicular axis steepening in 23 patients. In the non-incisional side on axis, corneal steepening was a relatively frequent pattern (n = 22 patients, 33%). Predictors studied for profile pattern of change were only near significance. Corneal radius of curvature changes were significantly correlated with astigmatic parameters.

CONCLUSIONS

Polynomial curve fitting is adequate for corneal biomechanical modeling of curvature and profile changes in the incisional and perpendicular axes of a 2.2-mm incision for phacoemulsification.

Intraindividual aqueous flare comparison after implantation of hydrophobic intraocular lenses with or without a heparin-coated surface

PURPOSE

To assess the efficacy of a heparin-surface-modified (HSM) hydrophobic acrylic intraocular lens (IOL) (EC-1YH PAL) and the same IOL without heparin coating (EC-1Y-PAL) by the flare and cell intensity in the anterior chamber after uneventful cataract surgery.

SETTING

Department of Ophthalmology, Paracelsus Medical University Salzburg, Austria.

DESIGN

Comparative case series.

METHODS

Routine phacoemulsification with randomized implantation of an HSM IOL in 1 eye (HSM IOL group) and an uncoated IOL (uncoated IOL group) in the fellow eye was performed. Postoperative inflammation was assessed objectively using a laser flare-cell meter (FM-600) preoperatively as well as 1 day and 1 and 3 months postoperatively. Aqueous cells in the anterior chamber, distance visual acuities, and subjective manifest refraction were also evaluated at each visit.

RESULTS

One hundred eyes (50 patients) were enrolled. In both groups, the mean flare values increased significantly from preoperatively to 1 day postoperatively (P<.001) and nearly reached preoperative values by 3 months postoperatively. One day postoperatively, the mean flare value was statistically significantly lower in the HSM IOL group (14.92 photons per millisecond [ph/ms] ± 7.47 [SD]) than in the uncoated IOL group (mean 16.73 ± 7.81 ph/ms) (P=.04); there was no statistically significant difference between groups 1 and 3 months postoperatively (both P>.58). The HSM IOL group had a greater and quicker decrease in aqueous cells, reaching statistical significance 1 month postoperatively (P=.01).

CONCLUSION

The HSM IOL showed a significant lower inflammatory reaction in the early postoperative stage with a faster disappearance of inflammatory signs.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Intraocular lens-shell technique: adjustment of the surgical procedure leads to greater safety when treating dense nuclear cataracts

Objective

To compare the efficacy and safety of the intraocular lens (IOL)-shell procedure versus conventional phacoemulsification for the surgical treatment of dense cataracts.

Methods

Eighty eyes with dense nuclear cataracts were enrolled in a prospective, randomized controlled study. Patients were assigned to two groups. In Group I, the IOL was traditionally implanted after all nuclear fragments were completely removed, and in Group II, the IOL was innovatively implanted in the bag before the last residual nuclear fragment was removed. This novel adjusted surgical procedure, named the “IOL-shell technique”, features use of the IOL as a protective barrier rather than simply as a refractive alternative, and it is conceptually different from the traditional step-by-step procedure. Clinical examinations, including uncorrected visual acuity, central corneal thickness (CCT), temporal clear corneal incision thickness and corneal endothelial cell density, were carried out.

Results

The inter-group difference in temporal corneal thickness was found to be of no statistical significance at any of the visits. Compared to eyes in Group I, those in Group II were shown to have significantly less corneal endothelial cell loss on both the 7th and 30th day following surgery. At 7 days after surgery, the mean corneal endothelial cell loss in Group II was 10.29%, compared to 14.37% in Group I (P<0.05). The mean endothelial cell loss measured on postoperative day 30 was 16.88% in Group II compared to 23.32% in Group I (P<0.05). On the 1st day after surgery, the mean CCT of eyes in Group II was significantly smaller compared to Group I (Group I vs. Group II: 19.42% vs. 13.50%, P<0.05).

Conclusions

Compared to conventional phacoemulsification, the IOL-shell technique was shown to be a relatively safer procedure without compromised efficiency for dense cataracts, and it caused less corneal endothelial cell loss and milder postoperative corneal edema (Clinical Trials Identifier: NCT02138123).

Trial Registration

ClinicalTrials.gov NCT02138123

Surgically induced astigmatism after 3.0 mm temporal and nasal clear corneal incisions in bilateral cataract surgery

Aims:

To compare the corneal refractive changes induced after 3.0 mm temporal and nasal corneal incisions in bilateral cataract surgery.

Materials and Methods:

This prospective study comprised a consecutive case series of 60 eyes from 30 patients with bilateral phacoemulsification that were implanted with a 6.0 mm foldable intraocular lens through a 3.0 mm horizontal clear corneal incision (temporal in the right eyes, nasal in the left eyes). The outcome measures were surgically induced astigmatism (SIA) and uncorrected visual acuity (UCVA) 1 and 3 months, post-operatively.

Results:

At 1 month, the mean SIA was 0.81 diopter (D) for the temporal incisions and 0.92 D for nasal incisions (P = 0.139). At 3 months, the mean SIA were 0.53 D for temporal incisions and 0.62 D for nasal incisions (P = 0.309). The UCVA was similar in the 2 incision groups before surgery, and at 1 and 3 months post-operatively.

Conclusion:

After bilateral cataract surgery using 3.0 mm temporal and nasal horizontal corneal incisions, the induced corneal astigmatic change was similar in both incision groups. Especially in Asian eyes, both temporal and nasal incisions (3.0 mm or less) would be favorable for astigmatism-neutral cataract surgery.

Analyses of surgically induced astigmatism and axis deviation in microcoaxial phacoemulsification

To evaluate surgically induced astigmatism (SIA) and axis deviation after coaxial microincision superotemporal clear corneal phacoemulsification incision in eyes with differently located steep axis. This prospective, comparative study included four groups of 45 eyes with age-related cataracts; each group underwent 2.2-mm superotemporal clear corneal incision (CCI) cataract surgery. The four groups of patients were divided by location of the steep axis. Groups were matched according to symmetry of the steep axis for both right and left eyes as follows--0°-45° of steep axis for right eyes, and 136°-180° for left eyes (group 1); 46°-90° for right eyes and 91°-135° for left eyes (group 2); 91°-135° for right eyes and 46°-90° for left eyes (group 3); and 136°-180° for right eyes and 0°-45° for left eyes (group 4). Outcome measures included changes in mean total astigmatism, SIA, and axis deviation. Astigmatism was measured by manual keratometry readings before surgery and week 1, week 4, week 8, and week 12 postoperatively. SIA was calculated by the vector analysis (Holladay-Cravy-Koch method). The magnitude of mean total astigmatism was lowest in group 3 and highest in group 1 at week 12. SIA was 0.39 diopters (D), 0.22 D, 0.17 D, and 0.28 D in group 1, group 2, group 3, and group 4, respectively. The change in astigmatic axis deviation was highest in group 3 (23.6 ± 16.6) (P < 0.05). Axis deviation and SIA were stable after week 4. Planning of CCI on or near the steep axis can help decrease corneal astigmatism.

Smaller Incision Size Leads to Higher Predictability in Microcoaxial Cataract Surgery

Purpose.

The aim of the study was to compare the clinical outcomes of a 1.8 mm, 2.2 mm, and 2.75 mm microcoaxial cataract surgery system.

Methods.

In this retrospective study, 129 eyes of 129 patients were included. Patients underwent phacoemulsification using a Stellaris system or an Infiniti system. The incision size was 1.8 mm, 2.2 mm, or 2.75 mm, respectively. Subjects were examined before surgery and 4 weeks after. The surgically induced astigmatism (SIA) was examined.

Results.

The SIA in the 1.8 mm group was statistically lower compared to the 2.2 mm group (p=0.046) and the 2.75 mm group (p=0.017). There was no significant difference between the 2.2 mm group and the 2.75 mm group.

Conclusions.

With the use of appropriate support systems, 1.8 mm incisions appear to result in less SIA than 2.2 mm and 2.75 mm incisions. Advantages may arise from this, especially in the implantation of aspheric, toric, or multifocal lenses.