Astigmatism

Trifocal lenses are part of the premium range of refractive-diffractive trifocal IOLs with advanced aspheric optics for excellent visual outcomes. They are single piece, posterior chamber foldable intraocular lenses. The optic is refractive-diffractive trifocal with the anterior surface being aspheric and the posterior surface with a square edge design. The lens is designed to provide all near, distance and intermediate vision and thereby reduce spectacle dependency. Toric version of trifocal intraocular lens is intended to correct astigmatism.

Phakic intraocular lenses are clear implantable lenses that are surgically placed either in anterior chamber (AC) or posterior chamber (PC) without removing the natural lens, enabling light to focus on the retina for improved uncorrected visual acuity. Phakic intraocular lenses demonstrate high optical quality and potential gain in visual acuity in myopic patients due to retinal magnification. Toric version of phakic intraocular lens is intended to correct both myopia and astigmatism.1

This is a prospective, randomized, simultaneous, contralateral eye study comparing visual outcomes for 4 different refractive technologies. This study will be conducted in 3 phases. Each phase will include at least 44 subjects undergoing refractive correction surgery for myopia or myopia with astigmatism. Each phase will compare Ray-Tracing LASIK to 1 of 3 other forms of corneal refractive surgery. The Phase 1 comparator will be KLEx (KeratoLenticule Extraction) using the Zeiss Visumax 800 Laser. The Phase 2 comparator will be WFO LASIK (Wavefront Optimized LASIK) using the Alcon EX500 Laser. The Phase 3 comparator will be Topography Guided LASIK (Contoura LASIK) also using the Alcon EX500 Laser. Patients will be selected from the Hoopes Vision patient population after a preliminary refractive evaluation has been completed. Patients who express an interest in the study will be consented. After informed consent has been obtained and the patient has completed a screening exam and met all study criteria they will be considered enrolled. For each Phase, randomization will ensure 50% of Right Eyes will receive Ray-Tracing LASIK and 50% of Right Eyes will receive the other comparator procedure. Subjects will be given postoperative care instructions and medications following standard of care practices. Subjects will return for a 1-day, 1-week, 1-month, 3-month, 6-month, and 12-month visit. Retreatments may only occur after all postoperative study visits have been completed and/or the subject has exited the study. At the preliminary screening visit, 1-month, 3-month, 6-month and 12-mont postoperative visits, patients will complete a Patient Participant Questionnaire.

To analyze the difference between measured total corneal astigmatism and actual corneal astigmatism under different region modes and optimize the region setting.

The goal of the investigation is to evaluate the accuracy of the Kids refraction software results performed with the phoropters Vision-R™700 and Vision-S™700 compared to the conventional subjective refraction method results performed with Vision-R™700. Phase A of the investigation will focus on the validation of the first version (Kids refraction software vA), and phase B will involve the second version (Kids refraction software vB). There are two phases in the investigation: Phase A: To evaluate the agreement of the subjective refraction results (Sphere, Cylinder, Axis, VA) between the Kids Refraction software vA (randomization between Vision-R or Vision-S devices) results and a conventional subjective refraction (performed with Vision-R), in a non-cycloplegic condition. Phase B: To evaluate the agreement of the subjective refraction results (Sphere, Cylinder, Axis, VA) between the Kids Refraction software vB with additional attention and cooperation stages (randomization between Vision-R or Vision-S devices) results and a conventional subjective refraction (performed with Vision-R), in a non-cycloplegic condition.

The participants will have a comprehensive eye examination once they express an interest in the study. This includes a slit lamp examination of the front of the eye and a dilated fundoscopic examination of the back of the eye. If there is any pathology noted that would exclude the participant from the study, then the investigator will inform the participant and make an appropriate referral. This is standard practice for laser in situ keratomileusis (LASIK) surgery, small incision lenticule extraction (SMILE) and photorefractive keratectomy (PRK) surgery. If the participant is deemed appropriate for the study after a comprehensive examination including computerized videokeratography, then the participant can be enrolled. These exams are also standard practice for LASIK, SMILE and PRK surgery. The Quality of Vision (QoV) Questionnaire will be administered following the pre-operative visit during which participants are enrolled and then at the three-month and twelve-month post- op visits before the participants are seen by the principle investigator. The questionnaire is the study intervention. The participant will undergo bilateral simultaneous LASIK eye surgery, SMILE or PRK surgery. The participants will be seen pre-operatively, on the day of surgery, post op day one, one month, three months, and twelve-months as part of the study. Participants may also be seen more frequently if required from a medical standpoint. The participant will receive topical antibiotics in each eye for one week following the procedure. LASIK treated eyes will receive pred forte 1% ophthalmic drops for one week to four weeks after treatment. All of this is within the usual and customary standard of care for the treatment of patients undergoing LASIK, SMILE and PRK surgery.

Myopia prevalence among Chinese children has increased markedly in recent years, representing a major public health concern. As myopia management options expand, expectations have shifted beyond efficacy alone to include wearing comfort, adaptation, and visual quality. Spectacle lenses remain the primary modality for myopia correction and play a critical role in daily visual experience. Optical defocus-based spectacle lenses with microlens designs have demonstrated efficacy in slowing myopia progression. Although existing studies have reported on the adaptation of spectacle lenses incorporating microlens designs, there are currently no data available for the A.M.L. series of lenses. This study aims to evaluate adaptation, wearing comfort, and user satisfaction with the A.M.L. series spectacle lenses. This is a one arm, prospective, interventional study, it will include 40 children, with adaptation, comfort, and satisfaction evaluated after 4 days, 1 week, and 2 weeks of lens wear.

Wavefront analysis and other objective methods are the mainstream approaches for assessing visual quality after refractive surgery, with high-order aberrations being the main observation indicators. Some studies have explored the correlation between various complications after SMILE surgery and high-order aberrations. However, research on lenticule retained after surgery has mainly focused on clinical management and case reports of overt lenticule retained, while there is a lack of high-quality observational studies on the population with covert lenticule retained (periphery residual lenticule) to serve as evidence. This often puts clinicians in a dilemma of whether to perform another surgery to remove the remnants. In summary, although research on lenticule retained after SMILE surgery is gradually increasing, systematic studies on their relationship with higher-order aberrations are still insufficient. This study aims to fill the gap in existing research by comparing and analyzing high-order aberrations between patients with and without periphery residual lenticule, providing a more comprehensive assessment of postoperative visual quality. This will offer important theoretical basis and practical guidance for improving SMILE surgical techniques and optimizing postoperative management.

This study aims to include 160 postoperative patients, who will be divided into a dry eye group and a normal group based on postoperative dry eye examination. Microbial samples of the patient's conjunctival sac will be collected, and changes in the ocular surface microbiota before and after surgery will be analyzed using 16S rRNA sequencing technology. The impact of changes in the ocular surface microbiota on FS-LASIK induced DES will also be analyzed, providing new treatment ideas for FS-LASIK induced DES patients and reducing the incidence of FS-LASIK related DES.

Corneal refractive surgery is an effective way to correct refractive error. Modern corneal refractive surgery for the correction of myopia or hyperopia can achieve or close to the expected goal, but to eliminate astigmatism is always one of the major problems of corneal refractive surgery. The key point in the correction of astigmatism is that as a vector parameter, astigmatism has both magnitude and direction. The angle error may be caused by the rotation of the patient's head position and the involuntary rotation of eyes. Phototherapeutic keratectomy can precisely cut the corneal tissue, and is often used in clinic to remove corneal scars or repair corneal surface morphology. In this study, the excimer laser therapeutic keratectomy mode was used to achieve accurate marking of the axis of astigmatism by setting the treatment laser parameters. With the help of the static cyclotorsion of the eye, the precise treatment of astigmatism could realize.