Treatment Of Presbyopia Research Articles

Pilocarpine in the Treatment of Presbyopia: Progress, Issues, and Future Prospects.

Presbyopia is a common age-related visual impairment. With the aging of the population, the incidence of presbyopia is increasing globally, becoming a worldwide public health concern. Treatment options for presbyopia include optical lens correction, surgical intervention, and pharmacological therapy. Pharmacological treatments for presbyopia are non-invasive, reversible, and have emerged over the past decade. Following the US Food and Drug Administration's approval of 1.25% pilocarpine for presbyopia, the use of pilocarpine and its compound formulations has gained increased attention, with some drugs entering clinical phase II/III trials ( www.clinicaltrials.gov ). Therefore, this article primarily describes and analyzes the progress of research on the use of pilocarpine and its compound formulations for presbyopia, as well as the challenges that remain to be addressed. The optimal dosage form, the optimal concentration, the long-term safety, and patient compliance should be further explored, and there is a lack of multi-center evidence-based medicine research to support it. The aim of this article is to provide a reference for researchers to conduct further in-depth investigations in this area.

Quantitative Evaluation of Human Lens and Lens Capsule Elasticity by Optical Coherence Elastography Based on a Rayleigh Wave Model.

Evaluating the biomechanical properties of the lens and lens capsule is important for the clinical diagnosis and treatment of age-related cataracts and presbyopia. In this study, we developed an optical coherent elastography technique to assess the elasticity of the lens and lens capsule in the human eye. With age, the mean Young's modulus of the lens increased from 12.28 ± 0.87 kPa to 18.59 ± 1.45 kPa, and the lens capsule increased from 6.33 ± 0.36 kPa to 13.33 ± 0.74 kPa. The results showed that the Young's modulus of the lens capsule and lens increased with age, with the Young's modulus of the lens significantly higher than that of the lens capsule. This study reports the assessment of the elasticity of the human lens and lens capsule by the OCE technique, indicating that it may provide a potential clinical tool for advancing research on diseases affecting the lens.

Extended Depth-of-Focus is a New Intraocular Lens Technology in the Treatment of Presbyopia: Review

Extended Depth-of-Focus is a New Intraocular Lens Technology in the Treatment of Presbyopia: Review

Real-world uptake of an innovative pupil expander device for cataract surgery: Implementation lessons learnt.

Cataract surgery in the eyes, where the pupil does not dilate despite using eye drops, is fraught with vision-threatening complications. About 11 per cent of eyes undergoing cataract surgery have non-dilating, small pupils. The increasing prevalence of benign prostatic hyperplasia (BPH), hypertension, diabetes and medications used for the same are the contributing factors. The recent Food and Drug Administration (FDA) approval for the use of miotic agents in the treatment of presbyopia will lead to a further rise in the number of non-dilating pupils. While pharmacological agents and other methods have been used, mechanical pupil expander devices are the only fail safe option. However, available devices had a steep learning curve and limitations which made them difficult to use, unpredictable and unsafe. With its patented single plane, hexagonal, notches and flanges design, the US FDA registered B-HEX Pupil Expander (Med Invent Devices Pvt. Ltd., India) overcame these limitations and fulfilled an unmet need. The B-HEX is machinable, rapidly produced, consistent, easy to use, safe, and affordable. Despite such advantages, implementation hurdles have restricted its availability to healthcare systems worldwide. Peer acceptance has been steadily growing, with the B-HEX becoming the market leader in India, as evidenced by numerous publications, videos and papers presented at international conferences and comments from opinion leaders endorsing its use. However, impractical regulatory requirements and resource constraints remain a great impediment to the global distribution of this novel invention. This has denied many patients the benefits of a superior and more affordable option. Though value continues to be added to the B-HEX by maintaining a strong intellectual property portfolio with internationally granted Patents and Trademark, increasing its user base, and garnering support from key opinion leaders, only a collaboration with the right partner will help scale up the global reach and make it a leader in the global market.

BCLA CLEAR presbyopia: Management with scleral techniques, lens softening, pharmaceutical and nutritional therapies

The aging eye undergoes the same progressive crosslinking which occurs throughout the body, resulting in increased rigidity of ocular connective tissues including the lens and the sclera which impact ocular functions. This offers the potential for a scleral treatment that is based on restoring normal biomechanical movements. Laser Scleral Microporation is a laser therapy that evaporates fractional areas of crosslinked tissues in the sclera, reducing ocular rigidity over critical anatomical zones of the accommodation apparatus, restoring the natural dynamic range of focus of the eye.Although controversial and challenged, an alternative theory for presbyopia is Schachar’s theory that suggests a reduction in the space between the ciliary processes and the crystalline lens. Widening of this space with expansion bands has been shown to aid near vision in people with presbyopia, a technique that has been used in the past but seems to be obsolete now.The use of drugs has been used in the treatment of presbyopia, either to cause pupil miosis to increase depth of focus, or an alteration in refractive error (to induce myopia in one eye to create monovision). Drugs and laser ablation of the crystalline lens have been used with the aim of softening the hardened lens. Poor nutrition and excess exposure to ultraviolet light have been implicated in the onset of presbyopia. Dietary nutritional supplements, lifestyle changes have also been shown to improve accommodation and the question arises whether these could be harnessed in a treatment for presbyopia as well.

Outcomes of Corneal Compound Myopic Astigmatism with Presbyopia by Zeiss PRESBYOND® Laser Blended Vision LASIK Using Default CRS-Master® Target Refractions for Reduced Anisometropia.

Background/Objectives: Presbyopia, a common age-related refractive error, affects over a billion people globally and significantly impacts daily life. Methods: This retrospective study analyzed 288 eyes of 144 patients undergoing LBV PRESBYOND® treatment for myopic presbyopia with astigmatism, aiming to evaluate precision, efficacy, safety, and stability over six months. Results: Key findings include high efficacy, with 99% of distance-eyes achieving uncorrected distance visual acuity (UDVA) of 20/25 or better, and 85% of near-eyes achieving UDVA of 20/32 or better. The results show excellent refractive outcomes, with 99% of long-sighted eyes and 97% of near-sighted eyes having a postoperative spherical equivalent within ±1.00 D. Safety was demonstrated by no loss of two or more Snellen lines after treatment, with 94% of patients maintaining corrected distance visual acuity (CDVA) before and after surgery. Conclusions: Overall, LBV PRESBYOND® proved effective, safe, and well tolerated for myopic presbyopia correction, offering satisfactory visual outcomes and potential spectacle independence for various distances. This study underscores the importance of individualized treatment based on patient age, highlighting the positive impact of binocular summation on visual function. This study contributes to the growing body of evidence supporting LBV PRESBYOND® as a viable option for addressing presbyopic myopia, offering insights into its efficacy and safety profile. Further research could explore postoperative stereopsis and long-term outcomes to enhance understanding and refine treatment protocols.

Therapeutic Effect of Topical Pilocarpine in Presbyopia Treatment

Purpose: To evaluate the safety, efficacy, and patient satisfaction during the application of low-dose Pilocarpine 1.25% as a treatment option in presbyopia. Study Type: A Prospective Interventional Clinical Trial. Materials and Methods: 120 patients with presbyopia were enrolled in this study, patients ages were between 40 and 55 years. A full history was taken and a detailed ocular examination was done. Measurements of refractive errors, uncorrected distant visual acuity (UCDVA), uncorrected near visual acuity (UCNVA), intraocular pressure, and pupil diameter and iris color assessment were performed before the enrollment and after half an hour, an hour, and three hours from the installation of topical pilocarpine 1.25%. Pilocarpine 1.25% drops were given for a month at a rate of one drop in the morning. Finally, a questionnaire was taken about the extent of satisfaction and reported side effects of the treatment. Results: Our study shows that the application of pilocarpine improved the average UCNVA from J3-J7 to J1-J2 with statistically significant differences (p=0.0001). A slight decrease in the mean UCDVA from 0.7-1.0 to 0.6-0.9 was noticed without statistically significant differences (p=0.09), and a decrease in intraocular pressure with statistically significant differences (p=0.01) was recorded. The self-assessment showed safety and patients were relatively satisfied when using the treatment. Conclusion: The application of low-dose pilocarpine 1.25% drops in a daily dose for the treatment of presbyopia is safe and improves near visual acuity, without a statistically significant effect on uncorrected distant visual acuity, while maintaining its efficacy during the month of the study

Model of zonular forces on the lens capsule during accommodation

How the human eye focuses for near; i.e. accommodates, is still being evaluated after more than 165 years. The mechanism of accommodation is essential for understanding the etiology and potential treatments for myopia, glaucoma and presbyopia. Presbyopia affects 100% of the population in the fifth decade of life. The lens is encased in a semi-elastic capsule with attached ligaments called zonules that mediate ciliary muscle forces to alter lens shape. The zonules are attached at the lens capsule equator. The fundamental issue is whether during accommodation all the zonules relax causing the central and peripheral lens surfaces to steepen, or the equatorial zonules are under increased tension while the anterior and posterior zonules relax causing the lens surface to peripherally flatten and centrally steepen while maintaining lens stability. Here we show with a balloon capsule zonular force model that increased equatorial zonular tension with relaxation of the anterior and posterior zonules replicates the topographical changes observed during in vivo rhesus and human accommodation of the lens capsule without lens stroma. The zonular forces required to simulate lens capsule configuration during in vivo accommodation are inconsistent with the general belief that all the zonules relax during accommodation.

Effects of Miosis on the Visual Acuity Space under Varying Conditions of Contrast and Ambient Luminance in Presbyopia.

Background: Presbyopia is an age-related ocular condition, typically affecting individuals aged over 40 years, characterized by a gradual and irreversible decline in the eye's ability to focus on nearby objects. Correction methods for presbyopia encompass the use of corrective lenses, surgical interventions (corneal or lens based), and, more recently, the FDA-approved topical administration of 1.25% pilocarpine. While prior research has demonstrated the efficacy of daily pilocarpine eye drop application in enhancing near visual acuity by increasing the depth of focus leveraging the pinhole effect, limited knowledge exists regarding its influence on visual acuity under varying conditions of contrast and ambient luminance. Methods: This study aims to investigate the impact of these variables on visual acuity, employing the VA-CAL test, among 11 emmetropic and 11 presbyopic volunteers who reported subjective difficulties with near vision. This study includes evaluations under natural conditions with a pinhole occluder (diameter of 2 mm), and subsequent administration of 1% pilocarpine (Pilomann, Bausch + Lomb, Laval, Canada). Results: The VA-CAL results demonstrate the expected, statistically significant effects of contrast and ambient luminance on visual acuity in both emmetropic and presbyopic volunteers. Furthermore, in emmetropic individuals, the application of pilocarpine resulted in a statistically significant reduction in visual acuity. In contrast, presbyopes did not exhibit statistically significant differences in the visual acuity space under either the pinhole or pilocarpine conditions when compared to natural conditions. Conclusions: The pharmacological treatment of presbyopia with pilocarpine eye drops, intended to enhance near vision, does not adversely affect visual acuity in presbyopes. This suggests that pilocarpine may offer a viable alternative for individuals averse to wearing corrective eyewear.

Pilocarpine HCl 1.25% for treatment of presbyopia after laser vision correction: pooled analysis of two phase 3 randomized trials (GEMINI 1 and 2).

To evaluate the efficacy of topical pilocarpine HCl 1.25% (Pilo) in treating presbyopia in individuals with or without a history of laser vision correction (laser-assisted in situ keratomileusis [LASIK] or photorefractive keratectomy [PRK]). Multiple clinical sites. Pooled analysis of 2 identically designed prospective, randomized, vehicle-controlled studies (GEMINI 1 and 2). Adults aged 40 to 55 years with presbyopia received once-daily Pilo or vehicle bilaterally for 30 days. Responder rates for ≥3-line improvement in mesopic, high-contrast, binocular distance-corrected near visual acuity (DCNVA) were determined on day 30. Among participants with a history of LASIK/PRK (n = 39 in the Pilo group, n = 41 in the vehicle group), responder rates for ≥3-line improvement in DCNVA on day 30 at hours 0.25, 0.5, 1, 3, 6, 8, and 10, respectively, were 16.7%, 38.9%, 41.7%, 37.8%, 16.2%, 13.9%, and 8.3% with Pilo and 0.0%, 2.6%, 10.5%, 5.1%, 7.7%, 2.6%, and 0.0% with vehicle. Responder rates in the LASIK/PRK subgroup were significantly higher with Pilo than vehicle at hours 0.25 ( P = .0087), 0.5 ( P = .0001), 1 ( P = .0022), and 3 ( P = .0005). In contrast, there were no significant differences in responder rates between Pilo-treated participants with and without LASIK/PRK. Among non-LASIK/PRK participants in the Pilo group (n = 336), responder rates for ≥3-line improvement in DCNVA on day 30 at hours 0.25, 0.5, 1, 3, 6, 8, and 10, respectively, were 16.8%, 32.7%, 39.0%, 28.0%, 17.4%, 12.6%, and 10.5%. Pilo treatment effectively and similarly improved DCNVA in presbyopes with or without a history of laser vision correction.

Rhegmatogenous Retinal Detachment Following Initiation of Pilocarpine Hydrochloride Ophthalmic Solution 1.25% for Treatment of Presbyopia.

Retinal detachment has previously been reported in association with topical miotic use for treatment of glaucoma. Pilocarpine hydrochloride 1.25% was recently FDA approved for treatment of presbyopia, with no reports of associated retinal detachments in the clinical trial data. Case report. We describe two novel cases of unilateral retinal detachment occurring within 10 days of initiation of pilocarpine 1.25% for treatment of presbyopia. The patients were pseudophakic men in their 60s or 70s with pre-existing retinal detachment risk factors such as high myopia, lattice degeneration, and prior retinal detachment. Both affected eyes were treated with pars plana vitrectomy and gas endotamponade with an uncomplicated post-operative course. Retinal detachment may be associated with pilocarpine 1.25% use. Caution should be used when considering prescribing this medication in patients with pre-existing retinal pathology.

The Role of Pilocarpine Eye Drops in the Management of Presbyopia: A Systematic Review

Introduction: Presbyopia is characterized by progressive loss of accommodation resulting in loss of visual acuity and is known to affect quality of life. Mainstay treatment include reading spectacles, contact lenses, and a series of surgical techniques. Until recently, pharmacologic treatment have been available. In this paper, we aim to review the role of pilocarpine eye drops in managing presbyopia. Methods: A comprehensive literature search was performed using Medline, EMBASE, and grey literature databases for articles from inception until 06 June 2024. Search terms included “presbyopia”, “presbyopia correction/treatment”, “pilocarpine”, and “pharmacological presbyopia treatment”. All relevant articles examining the efficacy and side effects of pilocarpine formulations and written in the English language were included in the review. Results: The initial search yielded 587 publications, of which 19 met our inclusion criteria and were included in analysis. Pilocarpine, a parasympathomimetic drug, increases the power of accommodation by increasing the lens thickness via the muscarinic receptors on the iris and ciliary muscles. Clinical trials utilizing pilocarpine eye drops in the management of presbyopia have reported positive outcomes in terms of near visual acuity. Pilocarpine HCL ophthalmic 1.25% formulation; Vuity™ and 0.4% formulation, Qlosi™ are currently the only approved pharmacologic treatment options shown to be effective in managing presbyopia. Conclusion: Overall, pilocarpine eye drops appear to be an effective option in improving near visual acuity in presbyopia patients. Long term follow-up data on the use of pilocarpine-based eye drops is not available. With the increase in the number of users overtime, the long-term effects of its prolonged use may be determined. Further research is needed to optimize the concentrations and combinations of pilocarpine and other substances to maximize efficacy and minimize adverse effects.

Impact of presbyopia treatment pilocarpine hydrochloride 1.25% on night-driving performance

ABSTRACT Clinical relevance Patients prescribed pilocarpine ophthalmic solution are advised to be cautious when driving at night, but studies evaluating the effects of pilocarpine hydrochloride ophthalmic solution 1.25% (pilo), approved to treat presbyopia, on driving at night are lacking. Background This double-masked, crossover, phase 3b study evaluated night-driving performance with pilo or the placebo once daily. Methods Forty-three adults (40–55 years) with presbyopia impacting daily activities and mesopic, high-contrast, binocular distance-corrected near vision 6/12–6/30 were randomised to bilateral treatment with pilo followed by placebo or placebo followed by pilo (with a ≥7-day washout between interventions). Night-driving performance was evaluated at twilight at a closed-circuit course. Primary efficacy endpoint: overall composite night-driving performance Z score at the end of the 7–14-day intervention period, 1 hour post-instillation. Pilo was considered non-inferior if the lower limit of the 95% confidence interval (CI) for the least squares mean difference (LSMD, pilo minus placebo) was >–0.25. Other efficacy endpoints: individual components of the night-driving performance test (hazard avoidance rate; road sign recognition rate and distance; pedestrians recognition distance; overall driving and lane-keeping times) and night-driving experience questionnaire. Safety included treatment-emergent adverse events (TEAEs). Results The mean overall composite Z scores were −0.121 (pilo) and 0.118 (placebo). The LSMD (pilo minus placebo) was −0.224 (95% CI, −0.346, −0.103), with 3 of the 7 individual tasks being significantly better with the placebo. The questionnaire did not reveal significant differences between pilo and the placebo. There were no serious or severe TEAEs and no TEAE-related discontinuations. The most common ocular TEAEs were headache and visual impairment with pilo (both 27.9%), and dry eye (7.0%) with the placebo. Conclusion The overall performance of night driving was inferior with pilo, compared with placebo. The study findings are consistent with the current class labelling and provide evidence to inform regulators and assist clinicians considering prescribing pilo to adults who seek treatment of presbyopia symptoms and drive at night. ClinicalTrials.gov identifier: NCT04837482.

Google Search Trends to assess public interest in and concern about Vuity for treating presbyopia.

To assess public awareness, interest, and concerns regarding Vuity (1.25% pilocarpine hydrochloride ophthalmic solution), an eye drop for the treatment of presbyopia, based on Google Trends. We used Google Trends that provides a relative search volume for queried terms, to evaluate searches for Vuity from June 30, 2021, to June 30, 2022, in the United States. The data for this study were downloaded on June 30, 2022. Main outcome measures were changes in relative search volumes for the terms "Vuity," "Eye drops for reading," "Eye drops for near vision," "Presbyopia," "Pilocarpine," and related popular search terms, such as "Vuity side effects," and "Vuity retinal detachment". Since the approval of Vuity on October 29, 2021, notable increases in the relative search volumes occurred for Vuity in October 2021, December 2021, and from March to April 2022, which coincided with its approval, availability, and subsequent direct-to-consumer advertising based on positive results of clinical trials. The direct-to-consumer advertising had the greatest impact on the search volume for Vuity. Specific interests included Vuity cost, where to buy it, and its side effects. Retinal detachment was the most highly searched Vuity side effect. Geographic variation was evident, with the relative search volumes highest for "Vuity" in Wyoming, followed by North Dakota. Google Trends is a useful tool for monitoring increases in public interest in Vuity for presbyopia. Public concerns regarding side effects warrant further real-world investigations of the causal relationship between Vuity and retinal detachment.

Refractive Outcomes of Cataract Surgery in Patients With Intrastromal Femtosecond Laser Treatment of Presbyopia (INTRACOR).

To evaluate the outcomes of cataract surgery with intraocular lens (IOL) implantation in patients who underwent intrastromal femtosecond laser treatment of presbyopia (INTRACOR). This was an interventional case series of 8 patients (10 eyes) who presented for cataract surgery 6.1 ± 3.2 years (mean ± standard deviation [SD]) after INTRACOR (Technolas Perfect Vision GmbH) treatment. A monofocal IOL was implanted in 9 eyes (7 patients) and a small-aperture IOL was implanted in 1 eye. The IOL power was calculated without adjustments using biometry obtained after the INTRACOR treatment. For additional calculations, keratometry obtained before the INTRACOR treatment was used. Postoperative examinations included visual acuity testing, manifest refraction, defocus curve, ocular biometry, corneal tomography, aberrometry, anterior segment optical coherence tomography, and slit-lamp examination. After the cataract surgery, the mean ± SD uncorrected distance visual acuity was 0.37 ± 0.17 logMAR, the corrected distance visual acuity was 0.10 ± 0.10 logMAR, and the manifest refraction spherical equivalent, adjusted to infinity, was +0.39 ± 0.63 diopters (D). Intermediate and near visual acuity, both uncorrected and distance-corrected, and distance-corrected defocus curves varied considerably among patients. Using biometry performed after INTRACOR, the traditional IOL power calculation formulas produced hyperopic outcomes, with the mean ± SD prediction error ranging from +0.72 ± 0.34 to +0.96 ± 0.41 D. Although the mean ± SD prediction error decreased (range: -0.34 ± 0.56 to -0.15 ± 0.53 D) when using keratometry obtained before INTRACOR, the accuracy remained low due to high variability. In patients with cataract who had previous INTRACOR treatment, IOL power calculation could be inaccurate, with a tendency toward hyperopic outcomes. These results require confirmation in more extensive studies. [J Refract Surg. 2023;39(10):676-682.].

Characterization of the viscoelastic properties of in vitro crystalline lens samples using ultrasound elastography

With aging, the stiffening of the crystalline lens [K. R. Heys et al., Mol. Vision 10, 956 (2004); R. F. Fisher, J. Physiol. 212(1), 147–180 (1971)] can hinder accommodation and reduce near-vision in more than 75% of individuals above 40 year old [T. R. Fricke et al., Ophthalmology 125(10), 1492–1499 (2018)], an impairment known as presbyopia. Mapping lens elasticity using shear wave elastography holds significant promise for monitoring potential treatments for presbyopia. However, because of the transparency of the lens to ultrasound, the tracking of waves can be performed only on its boundaries. The goal of this study is to characterize the viscoelastic properties of in vitro crystalline lens samples with a curvilinear harmonic method based on noise correlation algorithms. This procedure consists of precise measurements of the dispersion of surface waves across a large frequency range (0.1–3.5 kHz), thus allowing for clear identification of the wave properties needed to correctly estimate the elasticity. The proposed method was applied to gelatin phantoms and excised porcine lens samples. This enabled the observation of two regions in the dispersion curves: a sharp decrease in dispersion at low frequencies (<1 kHz), which was partly due to guided waves, and a smoother slope at high frequencies (>1 kHz), which was attributed to viscoelastic dispersion. In contrast to previous studies, shear elasticity and viscosity moduli were computed at higher frequencies with a Kelvin–Voigt model. If our approach confirms the shear viscosity of lenses, then the shear elastic moduli of lenses are almost an order of magnitude greater than the results of previous studies.

Efficacy, Safety, Predictability, and Stability of LASIK for Presbyopia Correction: A Systematic Review and Meta-analysis.

To determine the efficacy, safety, predictability, and stability of laser in situ keratomileusis (LASIK) in the treatment of presbyopia. The databases of CNKI, VIP, Wan-Fang, CBM, Chinese Clinical Registry, PubMed, The Cochrane Library, Web of Science, Embase, and ClinicalTrials.gov were searched until March 2023. The authors chose the studies of LASIK in the treatment of presbyopia. Outcomes were efficacy, safety, predictability, and stability. The review was registered in the international platform of registered systematic review and meta-analysis protocols (INPLASY202350005). A total of 28 non-randomized controlled trials (15,861 eyes) were included. The results showed that after LASIK, (1) the distance efficacy decreased (mean difference [MD]: 0.02, 95% CI: 0.0 to 0.03, P < .05) and the near efficacy increased (MD: -0.01, 95% CI: -0.19 to-0.02, P < .05); (2) the distance safety decreased (MD: 0.07, 95% CI: 0.04 to 0.10, P < .0001) and near safety increased (MD: -0.19, 95% CI: -0.39 to 0.02, P > .05); (3) the predictability within ±1.00 and ±0.50 D was 94% (relative risk [RR]: 0.94, 95% CI: 0.90 to 0.98, P < .001) and 80% (RR: 0.80, 95% CI: 0.74 to 0.86, P < .001), respectively; and (4) 6 months postoperatively, the percentage of spherical equivalent changing within ±0.50 D was 95% (RR: 0.95, 95% CI: 0.89 to 0.99, P < .001). The near efficacy, predictability, and stability of LASIK for presbyopia correction were satisfactory; however, the distance efficacy and distance safety decreased. [J Refract Surg. 2023;39(9):627-638.].

A new way of Presbyopia Treatment in Young People (20-40) years by Physical Exercises of the Eye Muscles.

Examination of degree of vision for patient to determine presbyopia in young people before and after therapeutic exercises and to know the amount of improvement in each session after taking a history of the patient and identification of treatment methods according the prescription with the eye moving to all directions and push it forward to reduce pressure on the eye muscle about 20 mints during the exercises (1-6) session in order to stimulate the weak eye.&#x0D; The appearance of presbyopia among young people from new cases because concentration for long periods and for more than 4 hours using the modern devices, which caused the occurrence phenomenon among young people and need for reading glasses. All patients were treated of and improved in the degree of consideration each session with therapeutic exercises after identifying and moving the weak eye muscle and found the examination and do not need to use any glasses to read during the examination and get visual acuity (VA=6/6 or 6/9).

Assessment of Visual Habituation Measured With the Halo & Glare Simulator and Its Impact on Patient Satisfaction Following Quadrifocal IOL Implantation.

To evaluate the levels of habituation and its influence on outcome satisfaction in patients who underwent bilateral multifocal intraocular lens (IOL) implantation. A total of 24 patients underwent bilateral multifocal IOL implantation surgery with the AcrySof IQ PanOptix trifocal diffractive IOL (Alcon Laboratories, Inc) following cataract extraction or for refractive purposes. Data were collected 3 and 6 months after surgery, which included subjective refraction, corrected and uncorrected visual acuity (distance, intermediate, near), a contrast sensitivity test, simulation with the Halo & Glare Simulator (Carl Zeiss Meditec AG), two visual quality surveys, and a slit-lamp examination by an ophthalmologist. All patients were spectacle independent for distance vision and 92% (n = 22) needed no visual aid for near vision. Minor visual acuity improvement was detected between both examinations at monocular uncorrected distance visual acuity (P = .025). Improvements of presence, size, and intensity of visual disturbances were not statistically significant, but overall patient satisfaction (P = .009) and Weber-Contrast sensitivity under mesopic conditions (P = .029) increased significantly. Diffractive multifocal IOLs are a stable treatment for presbyopia and/or cataract with a high spectacle independence rate. Visual disturbances caused by their optics do not decrease significantly between 3 and 6 months after surgery. Habituation and neuroadaptation play a significant role in patient satisfaction and contrast sensitivity during and possibly beyond that period. [J Refract Surg. 2023;39(8):510-517.].

On the controllability assessment of biofeedback eyeglasses used in Presbyopia treatment

In recent years, hybrid biofeedback systems utilizing user-controlled electrically tunable lenses have emerged as potential treatments for presbyopia. However, the controllability of these systems, closely linked to user adaptability, has received limited attention in the literature due to the challenges associated with obtaining a comprehensive system model. In this study, we present the design, implementation, and validation of an innovative experimental setup aimed at researching and evaluating the controllability of such a biofeedback system. Our setup incorporates a novel low-complexity model, considering the brain, natural lenses (e.g., the crystalline lens), and electrically tunable lenses, to establish a fundamental model for hybrid biofeedback systems. This model is developed based on an analysis of biofeedback systems, geometrical optics, and control theory, facilitating the identification of strategies to decouple system dynamics and enable precise controllability analysis. The proposed experimental setup was validated with volunteers, providing evidence that confirms the reliable operation of the biofeedback system. Our approach encourages a shift from conventional qualitative approaches toward quantitative evaluation of biofeedback devices. The proposed model and experimental setup hold the potential to statistically assess the controllability of hybrid biofeedback systems for correcting presbyopia, paving the way for further advancements in this field.