Visual and Refractive Efficacy of Panoptix Toric Intraocular Lens in a Clinical Setting.

Purpose: Trifocal Intraocular Lenses (IOLs) were developed to provide patients with effective near, intermediate and distance vision, thus minimizing spectacle dependency. Residual astigmatism has previously been shown to impact unaided visual acuity across all distances; therefore, to optimise the expected outcomes, consideration of preoperative corneal astigmatism is essential. The purpose of this study was to provide a real-world, multi-site review of visual and refractive outcomes in eyes undergoing implantation with the Panoptix Trifocal toric IOL platform. Patients and Methods: This study represents a two-fold approach. Patients who had previously undergone routine cataract removal and IOL insertion with the Panoptix Toric IOL were retrospectively analysed for routine efficacy and safety endpoints ("Retrospective Cohort"). Data was retrieved from the preoperative, surgical and postoperative visits (range 2-6 weeks). A further subset of patients undergoing lens removal and bilateral Panoptix Toric IOL insertion were identified at surgery ("Qualitative Cohort"). These patients underwent additional testing inclusive of quality of vision questionnaire and bilateral defocus curve. Results: A total of 466 eyes of 254 patients were included in the retrospective cohort. Between 91% and 98% of eyes, respectively, were within 0.50D and 1.00D of target. Mean absolute difference from Spherical Equivalent (SE) target was 0.22 ± 0.24Ds. Following surgery, 94% of eyes demonstrated a refractive astigmatism of 0.50D or less. Further, 61% eyes achieved uncorrected distance visual acuity (UDVA) of 20/20 or better, increasing to 94% achieving 20/32 or better. Seventy percent of eyes unilaterally achieved N5 unaided and 66.0% achieved N8 or better at intermediate. In the qualitative cohort, no patient described any symptom as significant or requested explant. Conclusion: In a real-world setting, the PanOptix toric trifocal IOL continues to demonstrate refractive accuracy and good visual performance at all focal distances. This IOL also exhibited good quality of vision, with minimally bothersome visual disturbances or photic phenomena.

Development of an In Situ Printing System With Human Platelet Lysate-Based Bio-Adhesive to Treat Corneal Perforations.

Purpose: Corneal perforation is a clinical emergency that can result in blindness. Currently corneal perforations are treated either by cyanoacrylate glue which is toxic to corneal cells, or by using commercial fibrin glue for small perforations. Both methods use manual delivery which lead to uncontrolled application of the glues to the corneal surface. Therefore, there is a need to develop a safe and effective alternative to artificial adhesives. Methods: Previously, our group developed a transparent human platelet lysate (hPL)-based biomaterial that accelerated corneal epithelial cells healing in vitro. This biomaterial was further characterized in this study using rheometry and adhesive test, and a two-component delivery system was developed for its application. An animal trial (5 New Zealand white rabbits) to compare impact of the biomaterial and cyanoacrylate glue (control group) on a 2 mm perforation was conducted to evaluate safety and efficacy. Results: The hPL-based biomaterial showed higher adhesiveness compared to commercial fibrin glue. Treatment rabbits had lower pain scores and faster recovery, despite generating similar scar-forming structure compared to controls. No secondary corneal ulcer was generated in rabbits treated with the bio-adhesive. Conclusions: This study reports an in situ printing system capable of delivering a hPL-based, transparent bio-adhesive and successfully treating small corneal perforations. The bio-adhesive-treated rabbits recovered faster and required no additional analgesia. Translational Relevance: The developed in situ hPL bio-adhesives treatment represents a new format of treating corneal perforation that is easy to use, allows for accurate application, and can be a potentially effective and pain relief treatment.

Prevalence of tear film hyperosmolarity in 1150 patients presenting for refractive surgery assessment.

PURPOSE: To present an analysis of tear film hyperosmolarity in a large, consecutive population and evaluate the correlation of ocular and systemic conditions with tear film osmolarity (TFO). SETTING: Private practice, Sydney, Australia. DESIGN: Single-center, retrospective, consecutive cohort. METHOD: Patients undergoing screening for laser refractive surgery from October 2017 to October 2020 were retrospectively reviewed. 1404 patients (n = 1357 standard, n = 47 postrefractive) undergoing screening for laser refractive surgery from October 2017 to October 2020 were reviewed. Routine examination included TFO and Ocular Surface Disease Index (OSDI) questionnaire. TFO was conducted prior to further tests, and patients refrained from topical eyedrops minimum 2 hours before the appointment. RESULTS: 1404 patients (n = 1357 standards, n = 47 postrefractive) patients were reviewed. Mean highest TFO in the standard population was 299.12 ± 11.94 mOsm/L, with 82.3% of eyes <308 mOsm/L indicating normal tear film homeostasis. The mean intereye TFO difference was 8.17 ± 8.60 mOsm/L, with 65.2% of eyes ≤8 mOsm/L. Mean highest TFO in the postrefractive subgroup was 299.72 ± 11.00 mOsm/L, with a mean intereye difference of 9.02 ± 6.92 mOsm/L. Postrefractive surgery patients indicated higher mean OSDI values of 15.28 ± 14.46 compared with the remainder of the population 9.69 ± 10.56 (P = .012). Significant correlation was demonstrated between TFO scores and OSDI normal classification in the standard population only (P = .005, r = 0.077). The use of contact lens correlated inversely with TFO and OSDI scores (P = .000, r = -0.136, and P = .000, r = -0.152, respectively). CONCLUSIONS: To the authors' knowledge, this study represents the largest available cohort of TFO scores in a standard population presenting for refractive surgery. Although most patients were found to fall within normal ranges, a reasonable percentage were diagnosed with tear hyperosmolarity and therefore at risk for dry eye disease.

Application of Collagen I and IV in Bioengineering Transparent Ocular Tissues.

Collagens represent a major group of structural proteins expressed in different tissues and display distinct and variable properties. Whilst collagens are non-transparent in the skin, they confer transparency in the cornea and crystalline lens of the eye. There are 28 types of collagen that all share a common triple helix structure yet differ in the composition of their α-chains leading to their different properties. The different organization of collagen fibers also contributes to the variable tissue morphology. The important ability of collagen to form different tissues has led to the exploration and application of collagen as a biomaterial. Collagen type I (Col-I) and collagen type IV (Col-IV) are the two primary collagens found in corneal and lens tissues. Both collagens provide structure and transparency, essential for a clear vision. This review explores the application of these two collagen types as novel biomaterials in bioengineering unique tissue that could be used to treat a variety of ocular diseases leading to blindness.

The Latest Evidence with Regards to Femtosecond Laser-Assisted Cataract Surgery and Its Use Post 2020.

Femtosecond laser-assisted cataract surgery (FLACS) was introduced with the hope of making cataract surgery safer and making the refractive result more predictable. It is only in the last four years that level 1 prospective randomised controlled trials (RCT) using current technology have been published. These, along with a meta-analysis of recent studies have shown that there seems to be little long-term visual benefit when using FLACS with monofocal lenses. The promised decrease in ultrasound energy required to remove a cataract has not been consistently demonstrated. There is level one evidence that the rate of posterior capsular rupture is less with FLACS using modern software. The round capsulotomy may be of increasing importance with the uptake of toric, multifocal and extended depth of focus lenses where a predictable capsulotomy size and precise placement of the lens becomes more important.

Human Platelets and Derived Products in Treating Ocular Surface Diseases - A Systematic Review.

Human platelet products have emerged as an alternative treatment for a range of ocular surface diseases such as dry eye and corneal ulceration. With significant therapeutic potential and increasing popularity, this study aimed to conduct a systematic review to detail the various production methods involved in generating platelet-derived products, compare and analyze clinical findings across available studies, and disseminate the relative advantages, limitations, and challenges of using platelet products to treat ocular surface disease. Thirty-eight clinical studies were identified, excluding studies conducted in animals and non-English language. Studies reported clinical outcomes, which included ocular surface disease index, best-corrected visual acuity, and corneal fluorescein staining. Most clinical studies reported improved patient signs and symptoms with an increasing variety of human platelet products including platelet rich plasma eye drops, human platelet lysate and platelet gels. However, due to variations in production methods, and study designs as well as confusing terminology, it was suggested that characterization of platelet products is needed for proper evaluation across studies.

Donation of discarded ocular tissue in patients undergoing SMILE laser refractive surgery: developing appropriate guidelines.

Tissue Biobanks represent an invaluable resource. Despite the majority of people supporting tissue donation, the actual rate remains low overall. Tissue discarded from surgical procedures represents a further avenue for collection for use in research. We aim to understand the information and consent requirements in a cohort of healthy, post-ophthalmic surgical subjects to optimise future tissue collection in living donors. Patients attending an ophthalmic clinic following refractive surgery for myopia (SMILE) were identified. Patient consent was implied with the completion of the provided survey. The questionnaire included gender, age range and education status. The majority of 31 subjects identified a benefit for future patients as the main motive for potential donation of discarded tissue (71%). Payment for the discarded tissue would not influence their decision in 77.4%. Explanation of the potential benefits of research was the most important information to consider before making a decision to donate. Only 12.9% of patients would have refused to include further information. Almost half of patients felt that the Biobank became the owner of tissue following donation. Current surgical patients may be more inclined to participate in research than the general public because of a sense of duty or an increased understanding of the role of research in evolving treatment. Despite minor uncertainty about the eventual use of the tissue and data, most subjects were positive to donation of discarded ocular tissue and de-identified information. Consent and education processes should be revised within an ophthalmic practice to minimise future patient anxiety.

Total keratometry in intraocular lens power calculations in eyes with previous laser refractive surgery.

IMPORTANCE: Intraocular lens (IOL) calculations in post-refractive cases remain a concern. Our study identifies improved options for surgeons. BACKGROUND: To evaluate and compare the prediction accuracy of IOL power calculation methods after previous laser refractive surgery using standard keratometry (SK), measured posterior corneal astigmatism (PCA) and total keratometry (TK). DESIGN: Retrospective consecutive cohort. PARTICIPANTS: A total of 50 consecutive patients (72 eyes) at a private institution who underwent cataract surgery with prior laser refractive procedures. METHODS: Methods using SK included ASCRS mean, Barrett True-K no history, Haigis-L and Shammas IOL formulae. Barrett True-K using posterior values (True K TK), Haigis and Holladay 1 Double-K methods using TK were also assessed. Post-surgery refraction was undertaken at minimum 3 weeks following surgery. MAIN OUTCOME MEASURES: Arithmetic and absolute IOL refractive prediction errors, variances in mean arithmetic IOL prediction error, and percentage of eyes within ±0.25D, ±0.50D, ±0.75D and ±1.00D of refractive prediction errors were compared. RESULTS: The Barrett True-K (TK) provided the lowest mean refractive prediction error (RPE) and variance for both prior myopes and hyperopes undergoing cataract surgery. The Barrett True-K (TK) exhibited the highest percentages of eyes within ±0.50D, ±0.75D and ±1.00D of the RPE compared to other formulae for prior myopic patients. CONCLUSIONS AND RELEVANCE: Accuracy of IOL power calculations in post-laser eyes can be improved by the addition of posterior corneal values as measured by the IOLMaster 700. The use of total keratometry may supplement outcomes when no prior refraction history is known.

Re-treatment in LASIK: To Flap Lift or Perform Surface Ablation.

PURPOSE: To review safety and efficacy outcomes following re-treatment for residual refractive errors in eyes with prior laser in situ keratomileusis (LASIK) and determine the most appropriate course of action for patients. METHODS: A review of all patients undergoing LASIK enhancement at a single refractive surgery center between 2012 and 2017 was undertaken. Refraction and biomicroscopy results before and after enhancement were collated and analyzed according to the method of enhancement (flap lift or surface ablation). RESULTS: A total of 108 eyes were included in the analysis; 58 eyes underwent flap lift and 50 underwent surface ablation retreatment with mean times to enhancement of 22.3 and 53.2 months, respectively. The mean spherical equivalent prior to enhancement was -0.43 ± 0.69 and -1.03 ± 1.01 diopters (D) for the flap lift and surface ablation groups, respectively. The absolute difference from intended refraction was statistically significant (lift 0.16 ± 0.24 versus surface ablation 0.31 ± 0.35 D; P = .01). The difference was more pronounced for eyes with prior hyperopia (P = .041). The incidence of haze following re-treatment was 3.4% in the flap lift group versus 10.0% in the surface ablation group, and 8.6% of the flap lift group had evidence of epithelial ingrowth, with 1 eye requiring washout. There was no correlation between time to enhancement, refraction, and incidence of complications following the enhancement procedure. CONCLUSIONS: There has been a trend toward treating residual LASIK refractive error through surface ablation. This review suggests that flap lift may result in a more accurate refractive outcome, albeit with an expected greater risk of epithelial ingrowth. [J Refract Surg. 2020;36(1):6-11.].

Development of a Platelet Lysate-Based Printable, Transparent Biomaterial With Regenerative Potential for Epithelial Corneal Injuries.

Purpose: To develop a human platelet lysate (hPL)-based bioink that is transparent and also encompasses the regenerative properties of hPL to facilitate wound healing. Methods: The effect of different batches of hPLand fetal bovine serum (FBS) on corneal epithelial cell growth and scratch assay was first examined using Incucyte Zoom. Various combinations of human fibrinogen (concentration range from 0.2 to 5 mg/mL) and thrombin (concentration from 1 to 10 U/mL) were combined with hPL to generate nine types of potential bioink. Rheology, transparency, and cell compatibility of bioinks were assessed and compared. The final selected bioink was used in an ex vivo corneal model to examine its ability in re-epithelization. Results: No significant difference was detected in cell proliferation and wound healing tests between different hPL batches at the same concentration. Scratch assay data showed that hPL had significantly higher effect on wound healing than FBS. Comparing across the nine bioinks, bioink 5 consisting of 10% hPL, 2 mg/mL fibrinogen, and 5 U/mL thrombin demonstrated all required mechanical and cellular properties and was able to regenerate the full-thickness epithelium ex vivo. Conclusions: The results showed that a transparent and adhesive bioink can be generated by combining hPL, fibrinogen, and thrombin together. The bioink can be directly applied to a human cornea to promote corneal re-epithelization with huge potential applications in corneal injuries. Translational Relevance: The developed transparent hPL-based ink with its adhesive and healing ability showed that it could be used as a new treatment option for corneal injuries.