Toric Monofocal Intraocular Lenses for the Correction of Astigmatism during Cataract Surgery: A Report by the American Academy of Ophthalmology.

PURPOSE: To review the published literature evaluating the visual and refractive outcomes and rotational stability of eyes implanted with toric monofocal intraocular lenses (IOLs) for the correction of keratometric astigmatism during cataract surgery and to compare those outcomes with outcomes of eyes implanted with nontoric monofocal IOLs and other astigmatism management methods performed during cataract surgery. This assessment was restricted to the toric IOLs available in the United States. METHODS: A literature search of English-language publications in the PubMed database was last conducted in July 2022. The search identified 906 potentially relevant citations, and after review of the abstracts, 63 were selected for full-text review. Twenty-one studies ultimately were determined to be relevant to the assessment criteria and were selected for inclusion. The panel methodologist assigned each a level of evidence rating; 12 studies were rated level I and 9 studies were rated level II. RESULTS: Eyes implanted with toric IOLs showed excellent postoperative uncorrected distance visual acuity (UCDVA), reduction of postoperative refractive astigmatism, and good rotational stability. Uncorrected distance visual acuity was better and postoperative cylinder was lower with toric IOLs, regardless of manufacturer, when compared with nontoric monofocal IOLs. Correcting pre-existing astigmatism with toric IOLs was more effective and predictable than using corneal relaxing incisions (CRIs), especially in the presence of higher magnitudes of astigmatism. CONCLUSIONS: Toric monofocal IOLs are effective in neutralizing pre-existing corneal astigmatism at the time of cataract surgery and result in better UCDVA and significant reductions in postoperative refractive astigmatism compared with nontoric monofocal IOLs. Toric IOLs result in better astigmatic correction than CRIs, particularly at high magnitudes of astigmatism. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Femtosecond Laser-Assisted Cataract Surgery: A Report by the American Academy of Ophthalmology.

PURPOSE: To evaluate refractive outcomes, safety, and cost-effectiveness of femtosecond laser-assisted cataract surgery (FLACS) compared with phacoemulsification cataract surgery (PCS). METHODS: A PubMed search of FLACS was conducted in August 2020. A total of 727 abstracts were reviewed and 33 were selected for full-text review. Twelve articles met inclusion criteria and were included in this assessment. The panel methodologist assigned a level of evidence rating of I to all 12 studies. RESULTS: No significant differences were found in mean uncorrected distance visual acuity, best-corrected distance visual acuity, or the percentage of eyes within ± 0.5 and ± 1 diopter of intended refractive target between FLACS and PCS. Intraoperative and postoperative complication rates were similar between the 2 groups, and most studies showed no difference in endothelial cell loss between FLACS and PCS at various time points between 1 and 6 months. In large randomized controlled studies in the United Kingdom and France, FLACS was less cost-effective than PCS. CONCLUSIONS: Both FLACS and PCS have similar excellent safety and refractive outcomes. At this time, one technique is not superior to the other, but economic analyses performed in some populations have shown that FLACS is less cost-effective.

Diagnosis and management of postrefractive surgery ectasia.

Postrefractive surgery ectasia is a serious, sight-threatening complication seen after the following procedures: laser in situ keratomileusis, photorefractive keratectomy, small-incision lenticule extraction, radial keratotomy, and/or arcuate keratotomy. Specific risk factors may include age, corneal thickness, degree of refractive error, corneal topographic changes including irregular astigmatism, percent tissue ablation, and residual stromal bed. Biomarkers may be a new option to help indicate who is at greatest risk for ectasia. Visual aids including spectacles or contacts lenses are often required to achieve optimal vision. Collagen crosslinking is the only treatment believed to stop progression of ectasia and prevent keratoplasty. Other surgical options may include topography-guided phototherapeutic keratectomy and intrastromal corneal ring segments. Ultimately, an "ounce of prevention is a pound of cure," so careful preoperative screening and ultimately offering the safest and most effective treatments for patients is arguably the most important job of the refractive surgeon.

Advantages of Small Incision Lenticule Extraction (SMILE) for Mass Eye and Ear Special Issue.

This review summarizes the advantages of Small-incision lenticule extraction (SMILE), including improved patient intraoperative experience, improved postoperative ocular surface, low incidence of regression, low re-treatment rates, and advantageous biomechanical corneal stability. Visual and refractive outcomes are similar to those achieved with LASIK, notably in large population studies. Since the inception of SMILE almost 10 years ago, the procedure has been rapidly growing in popularity. With the implementation of the novel SMILE technology in their practice, refractive surgeons generate excitement and potential for expanding the refractive market. Other parts of the world, including Asia, Europe, and Russia, SMILE has become the most popular refractive procedure performed. It is speculated that as SMILE continues to grow in popularity in the US since FDA approval in 2016 and more refractive surgeons implement this technology into their practice, it will drive an increase in the refractive market similar to what is seen in other countries.

Predicting Refractive Outcome of Small Incision Lenticule Extraction for Myopia Using Corneal Properties.

PURPOSE: To investigate whether preoperative corneal topographic and biomechanical parameters (CTBPs) predict postoperative residual refractive error (RRE). METHODS: We retrospectively included 151 eyes from 151 patients of small-incision lenticule extraction (SMILE) with target RRE of plano and 3-month measurements of refractive error from Tianjin Eye Hospital. Multivariate linear/logistic regressions were performed to associate age, gender, preoperative refractive error, lenticule thickness, and CTBPs with postoperative RRE/the occurrence of myopic RRE ≤ -0.25 diopter (D). Stepwise regression was used for feature selection. Leave-one-cross-validation was used for model evaluation by the area under the receiver operating characteristic curve (AUC). RESULTS: From linear regression, more myopic RRE was associated with higher preoperative myopia, intraocular pressure (IOP), flattest curvature of anterior cornea (AC), and highest concavity deformation (HCD), and was associated with lower anterior elevation, anterior asphericity, steepest curvature of AC, and second applanation velocity. The occurrence of ≤ -0.25 D RRE was associated with higher myopia, IOP, posterior elevation and asphericity, flattest curvature of AC, first applanation velocity and HCD, and was associated with lower first applanation stiffness parameter, central corneal thickness, anterior elevation and asphericity, steepest curvature of AC, and second applanation velocity as well as thinner lenticule thickness. Compared to the baseline model using age, gender, and preoperative refractive error, adding CTBPs significantly (P < 0.001) improved the AUC performance to 0.771 from 0.615. CONCLUSIONS: Postoperative outcomes of SMILE can be predicted by individual CTBPs. TRANSLATIONAL RELEVANCE: Our findings could be used to customize a refractive nomogram based on individual corneal properties improving outcomes and patient satisfaction.

Rate of Unplanned Vitrectomies in Femtosecond Laser-Assisted Cataract Surgery Compared to Conventional Phacoemulsification.

PURPOSE: To assess the rate of unplanned vitrectomies with femtosecond laser-assisted cataract surgery (FLACS) compared to conventional phacoemulsification at a single, high-volume, multi-surgeon ambulatory surgical center. METHODS: Retrospective, comparative study of phacoemulsification cases performed in a community-based ambulatory surgical center. A chart review of 2,480 consecutive FLACS procedures performed by 30 surgeons and 36,865 consecutive conventional phacoemulsification surgeries performed by 47 surgeons was conducted. The rate of unplanned vitrectomies was evaluated. In eyes with unplanned vitrectomy, the rates of posterior capsule tear, anterior capsule tear, and zonular dehiscence were analyzed. The unplanned vitrectomy rates between early and late FLACS cases were compared using thresholds of greater than 10, 20, and 50 cases. RESULTS: There were 230 (0.62%) and 16 (0.65%) unplanned vitrectomies in the conventional phacoemulsification and FLACS groups, respectively (P = .89). Of the cases requiring unplanned vitrectomy, posterior capsule tear, anterior capsule tear, and zonular dehiscence rates (conventional phacoemulsification vs FLACS) were 70.9% versus 56.3%, 8.3% versus 12.5%, and 20.9% versus 31.3%, respectively (P = .35). The difference in unplanned vitrectomy rates between early and late cases did not reach statistical significance in any threshold group. CONCLUSIONS: FLACS had a rate of unplanned vitrectomy comparable to conventional phacoemulsification. There was no statistically significant difference in unplanned vitrectomy rates between early and late FLACS cases suggesting a short learning curve. [J Refract Surg. 2018;34(9):610-614.].

Assessment of surgeon experience with femtosecond laser-assisted cataract surgery.

PURPOSE: To evaluate the collective user experience with an image-guided femtosecond laser (FSL) for cataract surgery in a high-volume, multi-surgeon, ambulatory surgical center. SUBJECTS AND METHODS: A detailed online survey was distributed to all surgeons in a single ambulatory surgical center who had performed cataract surgery using a FSL since its acquisition in December 2012. Information collected included the number of cases performed, typical surgical techniques and parameters, satisfaction with individual features of the laser (rated on a scale from 1=completely unsatisfied to 10=extremely satisfied) and commentary on ease of use and suggested improvements. RESULTS: Seventeen of 30 surgeons (56.7%) completed the survey, representing a case volume of 1,967 eyes. Fourteen surgeons (82.4%) felt they required ≤10 cases with the FSL to operate with the same safety and control as in standard phacoemulsification surgery. Satisfaction was highest for capsulotomies, lens fragmentation, lens softening, arcuate incisions and the graphic user interface (mean scores 9.4, 8.7, 8.7, 7.2 and 8.9, respectively). Preferred capsulotomy diameter was 4.8-5.2 mm (64.7% of respondents). About half (52.9%) of respondents centered the capsulotomy on the pupil and the other 47.1% centered the capsulotomy using optical coherence tomography. Most respondents (81.3%) preferred transepithelial arcuate incisions compared to intrastromal incisions. Satisfaction was lowest with FSL-created, main, clear corneal incisions and paracenteses (mean scores 4.4 and 4.2, respectively). CONCLUSION: Laser-assisted cataract surgery has a short learning curve and a high rate of user satisfaction. Further software and hardware development is warranted to improve user satisfaction with peripheral and clear corneal incisions.

Corneal Collagen Cross-Linking Complications.

Corneal cross-linking was approved by United States Food and Drug Administration for the treatment of progressive keratoconus in April 2016. As this approach becomes more widely used for the treatment of keratoconus and post-laser in situ keratomileusis (LASIK) ectasia, the medical community is becoming more familiar with potential complications associated with this procedure. This article aims to review the reported complications of collagen cross-linking for the treatment of keratoconus and post-LASIK ectasia.

Accuracy of Visual Estimation of LASIK Flap Thickness.

PURPOSE: To assess the accuracy of surgeons' visual estimation of LASIK flap thickness when created by a femtosecond laser by comparing it to ultrasound measurements. METHODS: Surgeons were asked to visually estimate the thickness of a femtosecond flap during the procedure. Total corneal thickness was measured by ultrasound pachymetry prior to the procedure and the stromal bed was similarly measured after flap lifting. The estimates from three experienced surgeons (cornea fellowship trained and more than 5 years in practice) were compared to those of three cornea fellows, with each surgeon evaluating 20 eyes (120 total). Surgeons were not told the thickness of the flaps unless required for safety reasons. RESULTS: The average difference between visual and ultrasonic estimation of LASIK flap thickness was 15.20 µm. The flap was 10 µm thicker than estimated in 37% of eyes, 20 µm thicker in 17% of eyes, and 30 µm thicker in 10% of eyes. The largest deviation was 53 µm. There was no statistically significant difference between the accuracy of experienced surgeons and fellows (P = .51). CONCLUSIONS: There are significant differences between surgeons' visual estimates and ultrasonic measurements of LASIK flap thickness. Relying on these visual estimates may lead to deeper excimer laser ablation than intended. This could lead to thinner residual stromal beds and higher percent tissue altered than planned. The authors recommend that surgeons measure flaps intraoperatively to maximize accuracy and safety. [J Refract Surg. 2017;33(11):765-767.].

A novel nomogram for the treatment of astigmatism with femtosecond-laser arcuate incisions at the time of cataract surgery.

PURPOSE: The purpose of this study was to determine an arcuate incision (AI) nomogram to treat astigmatism during femtosecond laser-assisted cataract surgery. METHODS: This is a retrospective, cohort study. Femtosecond laser (FSL)-assisted transepithelial AIs were created at a 9.0 mm optical zone, 80% depth, centered on the limbus. We modified the manual Donnenfeld limbal relaxing incision nomogram to 70% for with-the-rule (WTR), 80% for oblique (OBL), and 100% for against-the-rule (ATR) astigmatism. The correction index (CI) equaled AI-induced astigmatism/target-induced astigmatism. Measures included preoperative keratometric corneal cylinder (Pre Kcyl), postoperative Kcyl (Post Kcyl), and postoperative residual refractive astigmatism (Post RRA). RESULTS: Mean Pre Kcyl and 1-2 months Post RRA in 161 eyes of 116 patients were 0.626±0.417 diopters (D) (range 0.5-2 D), and 0.495±0.400 D (range 0-1.5 D), respectively. Mean absolute astigmatic changes (Pre Kcyl-Post Kcyl) without accounting for axis change in the WTR, ATR, and OBL groups were 0.165±0.383 D (P<0.001), 0.374±0.536 D (P<0.001), and 0.253±0.416 D (P=0.02), respectively. Mean absolute astigmatic changes using RRA as the postoperative measurement (Pre Kcyl-Post RRA) without accounting for axis change were 0.440±0.461 D (P<0.001), 0.238±0.571 D (P<0.05), 0.154±0.450 (P=0.111) in WTR, ATR, and OBL groups, respectively. CIs for WTR, ATR, and OBL were 0.53, 1.01, and 0.95, respectively. There were no intraoperative or postoperative complications related to the AIs. CONCLUSION: Transepithelial FSL-AIs using the modified Donnenfeld nomogram show potential for management of mild to moderate corneal astigmatism. An increase in the magnitude or reduction of the optical zone size for the treatment of WTR and ATR astigmatism for this nomogram may further improve refractive accuracy.

Femtosecond laser-assisted compared with standard cataract surgery for removal of advanced cataracts.

PURPOSE: To compare effective phacoemulsification time (EPT) for the removal of brunescent cataracts treated with femtosecond laser-assisted cataract surgery with standard cataract phacoemulsification techniques. SETTING: Ruhr University Eye Hospital, Bochum, Germany. DESIGN: Comparative prospective case study. METHODS: The Lens Opacities Classification System III (LOCS III) grading system was used to measure eyes divided into 4 groups having cataract surgery. Groups 1 and 2 contained eyes with LOCS III grade nuclear opalescence (NO) 3 cataracts treated with standard cataract surgery and femtosecond laser-assisted cataract surgery, respectively. Groups 3 and 4 contained brunescent cataracts, LOCS III grades NO5, treated with standard cataract surgery and femtosecond laser-assisted cataract surgery, respectively. RESULTS: There were 240 eyes, with 60 eyes in each group. The EPT in Group 1 ranged from 0.46 to 3.10 (mean 1.38); the EPT in all eyes in Group 2 was 0 (P < .001). The EPT in Groups 3 and 4 was 2.12 to 19.29 (mean 6.85) and 0 to 6.75 (mean 1.35), respectively (P < .001). A comparison between EPT in Groups 1 and 4 showed that EPT in Group 4 was also lower than in Group 1 (P = .013). Groups 4 and 1 were the most statistically similar of all groups compared, suggesting that EPT for a femtosecond laser-treated grade 5 cataract was most similar to that of a standard-treated grade 3 cataract. CONCLUSION: Femtosecond laser pretreatment for brunescent cataracts allowed for a significant reduction in EPT compared with manual standard phacoemulsification techniques. FINANCIAL DISCLOSURE: Drs. Hatch, Talamo, and Dick are consultants to Abbott Medical Optics, Inc. Dr. Schultz has no financial or proprietary interest in any material or method mentioned.

Intraocular lens power selection and positioning with and without intraoperative aberrometry.

PURPOSE: To determine the value of intraoperative aberrometry in cases of toric intraocular lens (IOL) implantation and positioning. METHODS: In this non-randomized retrospective comparative trial, two groups of eyes underwent cataract extraction with toric IOL implantation: the aberrometry group (n = 37 eyes), where toric IOL power and alignment were determined before surgery with automated keratometry, standard optical biometry, and an online calculator and then refined using intraoperative aberrometry, and the toric calculator group (n = 27 eyes), where IOL selection was performed in a similar manner but without intraoperative aberrometry. The primary outcome measure was mean postoperative residual refractive astigmatism (RRA). RESULTS: Mean RRA measured at follow-up after surgery was 0.46 ± 0.42 and 0.68 ± 0.34 diopters (D) in the aberrometry and toric calculator groups, respectively (P = .0153). A 75% and 57% reduction in cylinder was noted between preoperative keratometric astigmatism and postoperative RRA in the aberrometry and toric calculator groups, respectively (P = .0027). RRA of 0.25 D or less, 0.50 D or less, 0.75 D or less, and 1.00 D or less was seen 38%, 78%, 86%, and 95% of the time, respectively, in the aberrometry group and 22%, 33%, 74%, and 89% of the time, respectively, in the toric calculator group. These data show that the chance of a patient being in a lower postoperative RRA range increased when intraoperative aberrometry was used (P = .0130). CONCLUSIONS: Patients undergoing cataract extraction with toric IOL placement aided by intraoperative aberrometry were 2.4 times more likely to have less than 0.50 D of RRA compared to standard methods.

Laser-assisted cataract surgery: benefits and barriers.

PURPOSE OF REVIEW: The use of the femtosecond laser (FSL) in cataract surgery may represent the largest advancement in the field since the inception of phacoemulsification. The goal of this review is to outline the benefits of and barriers to this technology. RECENT FINDINGS: There are several significant potential benefits of the FSL in cataract surgery over conventional manual cataract surgery: precise capsulotomy formation, clear corneal and limbal relaxing incision construction, lens fragmentation, and lens softening. Evidence suggests that refractive benefits include more precise effective lens position as well as reduced effective phacoemulsification time with the use of FSL compared with manual surgery. Patients with conditions such as Fuchs' endothelial dystrophy, pseudoexfoliation, history of trauma, or brunescent cataracts may particularly benefit from this technology. There are significant financial and logistical issues to consider prior to the purchase of a FSL, including the cost of the laser, and charges to patients, and how the laser affects the patient flow in the operating room. SUMMARY: The FSL may significantly change the current approach to cataract surgery.

Delayed Epithelial Closure After PRK Associated With Topical Besifloxacin Use.

PURPOSE: To report the observation of prolonged reepithelialization after photorefractive keratectomy (PRK) associated with the use of besifloxacin 0.6% (Besivance; Bausch & Lomb, Rochester, NY) underneath bandage contact lenses (BCLs) placed during surgery. METHODS: An office-based private practice and retrospective chart review. The healing parameters examined included epithelial healing time, haze formation, discomfort, and visual recovery of 4 patients (7 eyes) treated with besifloxacin 0.6% under BCLs placed after the PRK was performed. RESULTS: All the eyes had delayed epithelial closure (mean, 8.8 days; range 5-13 days). All the patients experienced a delayed visual recovery and significant pain after the surgery, and 2 of 4 patients experienced recurrent corneal erosions for weeks to months after they underwent the PRK. All but 1 eye developed corneal haze persisting for 1 year or more after the surgery. Only 1 eye among the 7 eyes treated with besifloxacin 0.6% under the BCL had 20/20 or better uncorrected visual acuity 3 months postoperatively. CONCLUSIONS: All the patients treated with besifloxacin 0.6% on the stromal bed exhibited significant problems with corneal epithelial healing and delayed visual recovery. We caution the use of besifloxacin 0.6% underneath a BCL during a PRK or other ocular surface surgeries requiring corneal epithelial debridement.