Contrast Sensitivity with Center-distance Multifocal Soft Contact Lenses

BCLA CLEAR Presbyopia: Management with contact lenses and spectacles

This paper seeks to outline the history, market situation, clinical management and product performance related to the correction of presbyopia with both contact lenses and spectacles. The history of the development of various optical forms of presbyopic correction are reviewed, and an overview is presented of the current market status of contact lenses and spectacles. Clinical considerations in the fitting and aftercare of presbyopic contact lens and spectacle lens wearers are presented, with general recommendations for best practice. Current options for contact lens correction of presbyopia include soft simultaneous, rigid translating and rigid simultaneous designs, in addition to monovision. Spectacle options include single vision lenses, bifocal lenses and a range of progressive addition lenses. The comparative performance of both contact lens and spectacle lens options is presented. With a significant proportion of the global population now being presbyopic, this overview is particularly timely and is designed to act as a guide for researchers, industry and eyecare practitioners alike.

Efficacy of a new refractive multifocal contact lens for presbyopia

This prospective single-arm study aimed to evaluate the clinical efficacy and safety of a refractive multifocal contact lens for the correction of presbyopia in 22 patients. The participants underwent clinical examinations before and 1 week after wearing a refractive multifocal contact lens (OptaCon ZOOM). The primary endpoints were the corrected distance visual acuity (CDVA) and distance-corrected near visual acuity (DCNVA). Defocus curve, contrast sensitivity, and ocular surface disease index (OSDI) were analyzed. A slit-lamp examination was performed for safety analysis. Contact lens comfort and patient satisfaction were assessed using a questionnaire. No significant difference in CDVA was observed before and 1 week after refractive multifocal contact lens use (p = 0.127), whereas DCNVA was significantly improved after 1 week (p < 0.001). The contrast sensitivity was not significantly affected at any spatial frequency under mesopic or photopic conditions. OSDI was significantly increased (p = 0.023). The patient-reported satisfaction scores were 96.2, 91.9, and 85.0 out of 100 at far, intermediate, and near distances, respectively. No significant adverse events were observed. Refractive multifocal contact lenses improved near vision while maintaining distance vision in presbyopic patients, without compromising contrast sensitivity. The study results suggest that OptaCon ZOOM can be considered safe and effective for the correction of presbyopia.

Efficacy of Soft Contact Lenses for Myopia Control: A Systematic Review

PURPOSE

To summarize and analyze critically the scientific evidence focused on the effectiveness of the use of hydrophilic contact lenses (HCLs) in myopia control, as well as their impact on visual quality and the involvement on the accommodative and binocular function.

METHODS

This systematic review was developed selecting all original studies which evaluated HCLs for myopia control with follow-up of at least 1 year. Eligible randomized controlled trials (RCTs) were retrieved from PubMed MEDLINE and Scopus. Methodological quality of the studies was assessed using the Critical Appraisal Skills Programme (CASP) for RCTs.

RESULTS

The search provided a total of 276 articles, selecting 13 according to the inclusion and exclusion criteria. The majority of studies evaluating the effectiveness of HCL showed a good efficacy in myopia progression, providing a good quality of vision. The quality of these studies was found to be suitable according to the CASP tool. The accommodative and binocular function with these lenses was evaluated in few studies, reporting a trend to an increase in the accommodative response and exophoria in near vision, while maintaining good level of stereopsis. Aberrometry and pupillometry were only studied in one trial, in which the authors did not find changes in these variables after the use of a myopia control HCL.

CONCLUSIONS

There is a strong evidence about the effectiveness of different HCLs designs for slowing down myopia progression in children, providing all of them good levels of visual quality. However, there is still poor evidence about changes in accommodation and binocular function, as well as in pupil size and aberrometry with myopia control HCLs, being necessary more studies focused on this issue.

Intraocular Straylight and Multifocal Soft Contact Lens Fit With a Myopia Control Approach

OBJECTIVES

Center-distance multifocal contact lenses (MFCLs) are used to slow myopia progression. We examined the effect of two MFCLs on intraocular straylight values in myopic individuals.

METHODS

Twenty-five young myopic adults were enrolled and were fit with three contact lenses (Biofinity sphere, Biofinity Multifocal, and NaturalVue Multifocal) in a random order over two study visits. Pupil size (NeurOptics VIP-300, Laguna Hills, CA) and contact lens centration were measured. Right eye intraocular straylight measurements were collected (OCULUS C-Quant; Wetzlar, Germany) and compared with a spectacle trial lens. Log straylight (LogSL) values and straylight residuals were analyzed using repeated-measures analyses of variance with Tukey-corrected post hoc t -tests.

RESULTS

The mean participant age (±SD) was 24.1±1.5 years, and right eye spherical equivalent refractive error was -3.38±1.53 DS. There was no difference in mesopic pupil size between visits ( P =0.68) and no difference in contact lens centration between lenses ( P =0.99). LogSL values differed by lens type ( P =0.004). LogSL with the spectacle trial lens was significantly greater than with each contact lens type (all P <0.05), but there were no significant differences in LogSL between the three contact lenses (all P >0.05). There was no difference between the three contact lens designs for straylight residuals ( P =0.33).

CONCLUSIONS

Measured intraocular straylight for both MFCLs was not different than with a spherical soft contact lens. A significant increase in intraocular straylight with spectacle trial lens correction was observed compared with all contact lenses.

Effect of myopia-control lenses on central and peripheral visual performance in myopic children

PURPOSE

To evaluate the short-term effects of three myopia-control lenses, which impose peripheral myopic defocus while providing clear central vision, on central and peripheral visual performance in myopic children.

METHODS

Twenty-one myopic children were enrolled in the study. Central visual performance was assessed using the quick contrast sensitivity function. Peripheral visual performance was evaluated by measuring peripheral contrast threshold and global motion perception, while subjects maintained fixation through the central portion of the lens. Single-vision spectacle lenses (SVL), spectacle lenses with highly aspherical lenslets (HAL) and defocus-incorporated soft contact (DISC) lenses were evaluated in random order, followed by orthokeratology (OK) lenses. All tests were performed monocularly on the right eye.

RESULTS

The area under the log contrast sensitivity function (AULCSF) with DISC lenses was lower than that with SVL (1.14 vs. 1.40, p < 0.001) and HAL (1.14 vs. 1.33, p = 0.001). HAL increased the temporal visual field contrast threshold compared with OK lenses (p = 0.04), and OK lenses decreased the superior visual field contrast threshold compared with that of SVL (p = 0.04) and HAL (p = 0.005). HAL also increased the peripheral coherence threshold for identifying the contraction movement compared with OK lenses (p = 0.01).

CONCLUSIONS

The short-term use of these optical interventions for myopia control exhibited measurable differences in central and peripheral visual performance. Relevant attention could be paid to these differences, especially when children switch to different treatments. DISC lenses exhibited worse central contrast sensitivity than SVL and HAL. Imposing peripheral defocus signals did not affect children's peripheral visual performance compared with SVL. However, considering the poorer peripheral visual performance provided by HAL, OK lenses are recommended for children if there are specific demands for global scene recognition and motion perception.

Exploring the impact of optical corrections on visual functions in myopia control-a scoping review

PURPOSE

Myopia is controlled optically with peripheral defocus spectacles, multifocal contact lenses, or orthokeratology lenses. However, it is unknown which optical correction will improve visual performance. This scoping review aimed to identify and summarize studies on various visual functions using optical corrections for myopia control.

METHODS

To develop the search strategy, population (Myopia), concept (visual performance), and context (unrestricted race/region) were used. PubMed, SCOPUS, Cochrane Library, and Web of Science databases were searched using the keywords myopia, contrast sensitivity, high and low contrast visual acuity, stereopsis, and optical correction of myopia control. This scoping review protocol was registered in the Open Science Framework registry and followed the framework for scoping review outlined by the Joanna Briggs Institute.

RESULTS

Eight studies (n = 8) met the inclusion criteria and were included in the review. Four were conducted in Europe, two were conducted in China, and one was conducted in Japan and Singapore. Five studies were randomized controlled trials, out of which three used contact lenses and two studies used peripheral defocus spectacles lenses. Studies ranged from one day to 2 years. Three studies that used orthokeratology lenses were prospective study designs. Among the studies that used orthokeratology lenses and contact lenses, two studies measured the contrast sensitivity function with CSV1000 (Vector Vision) under mesopic and photopic conditions, with and without glare. Two studies measured the central and peripheral contrast sensitivity using psychophysics experiments. High and low contrast visual acuity was measured using the Freiburg Vision Test (n = 1) and ETDRS charts (n = 3), and stereopsis was assessed using a random dot stereogram (n = 1). The studies showed a reduction in central and peripheral contrast sensitivity function and low contrast acuity when treated with multifocal contact lenses, orthokeratology lenses, and peripheral defocus lenses compared with single-vision lenses.

CONCLUSION

This scoping review found a reduction in central and peripheral contrast sensitivity function, as well as low contrast visual acuity when using various optical corrections for myopia control, while high-contrast visual acuity remained the same. The impact of visual functions may not influence the effectiveness of myopia control. Eye care practitioners should provide awareness to the parent and patient population about the potential visual impact of recent designs for optical corrections of myopia control.

Visual Performance and Higher Order Aberrations Obtained With Omafilcon A Dual-Focus and Single-Vision Contact Lens Designs

OBJECTIVE

The purpose of this study was to assess the visual performance and monochromatic higher-order aberrations (HOAs) obtained while wearing a MiSight dual-focus (DF) contact lenses (CL) in comparison with a single-vision contact lens (SVCL).

METHODS

A randomized, double-masked, cross-over study was performed. Participants were fitted with a DFCL and a SVCL composed of the same material (omafilcon A) and parameters. Logarithm of the Minimum Angle of Resolution high-contrast (100%) and low-contrast (10%) visual acuity (VA) and contrast sensitivity (CS) for 3, 6, 12, and 18 cycles per degree were measured. Higher-order aberrations were also evaluated using a Hartmann-Shack aberrometer with the CLs on.

RESULTS

Twenty-four subjects (21 females and 3 males) with a mean age of 21.9±1.9 years (range: 18-27) were included. Low-contrast VA was significantly lower with the DFCL regarding the SVCL design (0.39±0.23 vs 0.25±0.18, P=0.002). However, there were no differences in high-contrast VA between both CLs (-0.03±0.10 vs -0.09±0.14, P=0.187). Contrast sensitivity was lower with the DFCL under all spatial frequencies (P≤0.048). Second-, third-, fourth-, and fifth-order aberrations were significantly (P<0.001) higher for the DFCL. There were also significant differences between DFCL and SVCL in defocus (0.87±0.28 vs 0.16±0.35, P<0.001), oblique trefoil (-0.16±0.27 vs -0.01±0.08, P=0.005), vertical coma (0.13±0.17 vs 0.00±0.08, P=0.002), and spherical aberration (0.09±0.11 vs -0.02±0.05, P=0.002).

CONCLUSION

Visual performance for detecting low-contrast targets is reduced when wearing MiSight DFCL compared with a SVCL with the same material. The main reason might be the induction of second-order and HOAs by the DFCL design.

Quality of life after wearing multifocal contact lenses for myopia control for 2 weeks in the BLINK Study

PURPOSE

To validate Pediatric Refractive Error Profile 2 (PREP2) subscales that can be used to evaluate contact lens wearers and compare vision-specific quality of life measurements between children wearing multifocal and single vision contact lenses for 2 weeks.

METHODS

Two hundred and ninety-four myopic children aged 7-11 years (inclusive) were enrolled in the 3-year, double-masked Bifocal Lenses In Nearsighted Kids (BLINK) Study. Participants completed the PREP2 survey after having worn contact lenses for 2 weeks. The Vision, Symptoms, Activities and Overall PREP2 subscales were used to compare participants' subjective assessment while wearing +1.50 or +2.50 D add multifocal or single vision contact lenses. Rasch analysis was used to validate each subscale and to compare participants' subjective assessment of contact lens wear.

RESULTS

Item fit to the Rasch model was good for all scales, with no individual items having infit mean square statistics outside the recommended range (0.7-1.3). Response category function was acceptable for all subscales, with ordered category thresholds. Measurement precision, assessed by the Rasch person reliability statistic, was less than ideal (≥0.8) for three of the subscales, but met the minimum acceptable standard of 0.5. Scores for the Vision subscale differed by treatment assignment (p = 0.03), indicating that participants with the highest add power reported statistically worse quality of vision, although the difference was only 3.9 units on a scale of 1-100. Girls reported fewer symptoms than boys (p = 0.006), but there were no other differences between boys and girls.

CONCLUSIONS

Rasch analysis demonstrates that the PREP2 survey is a valid instrument for assessing refractive error-specific quality of life. These results suggest that vision-related quality of life is not meaningfully affected by 2 weeks of soft multifocal contact lens wear for myopia control.

PRESBYOND Laser Blended Vision LASIK in Commercial and Military Pilots Requiring Class 1 Medical Certification

PURPOSE

To report the outcomes of PRESBYOND Laser Blended Vision LASIK (Carl Zeiss Meditec AG) in presbyopic commercial and military pilots requiring Class 1 aeromedical certification.

METHODS

This was a retrospective study of 23 consecutive pilots who underwent PRESBYOND Laser Blended Vision LASIK. Postoperative visits were conducted at 1 day and 1, 3, and 12 months. Standard outcomes analysis was performed using the data at 12 months. Objective quality of vision measures including mesopic contrast sensitivity (CSV-1000; VectorVision), Ocular Scatter Index (HD Analyzer; Keeler), and straylight (C-Quant; Oculus Optikgeräte GmbH) were determined before and 3 months after surgery. A questionnaire to assess the functional vision of pilots before and after surgery was derived to record subjective outcomes.

RESULTS

Of the 23 pilots treated, data were available at 12 months for 22 pilots (95.7%) and at 3 months for 1 pilot (4.3%). Median age was 55 years (range: 42 to 65 years). At 12 months, binocular uncorrected distance visual acuity was 20/20 or better in 100% and 20/16 or better in 52% of pilots. Binocular uncorrected intermediate visual acuity was J3 in 73%, J5 in 95%, and J10 in 100% of pilots. Binocular uncorrected near visual acuity was J1 or better in 78% and J2 or better in 100% of pilots. Mean postoperative spherical equivalent refraction relative to the target was -0.04 ± 0.34 diopters (D) (range: -0.63 to +0.63 D), with 93% within ±0.50 D. There was a statistically significant increase in contrast sensitivity at 3, 6, 12, and 18 cpd. C-Quant straylight was 1.07 ± 0.16 before surgery and 1.06 ± 0.16 at 1 to 3 months after surgery (P = .705). All pilots achieved Class 1 medical certification from the United Kingdom Civil Aviation Authority and resumed flying. All pilots reported improved functionality compared to the previous vision correction method.

CONCLUSIONS

PRESBYOND Laser Blended Vision LASIK enabled presbyopic commercial pilots to continue to fly without the need for glasses. With consideration of the visually challenging cockpit environment, PRESBYOND Laser Blended Vision LASIK provides clear continuous vision for tasks at near, intermediate, and far distance. Class 1 pilots reported a subjective improvement in visual tasks and comfort following surgery. [J Refract Surg. 2023;39(1):6-14.].

The influence of contact lenses with different optical designs on the binocular vision and visual behavior of young adults

Theoretically, contact lenses change the accommodation and vergence demands of the eyes and directly or indirectly influence binocular vision. The purpose of this study was to investigate the influence of different optical designs of contact lenses on binocular vision and visual behavior among young adults. In this randomized, single-blinded experimental study, visual behavioral performance (VBP) and Ocular Surface Disease Index questionnaires were used for preliminary screening. Nineteen myopic subjects aged 20-26 years (21.59 ± 1.40 years) participated in the study. Baseline values for subjective refraction and binocular visual functions were evaluated. All the subjects were randomly grouped to wear different optical designs of single-vision, progressive, and bifocal contact lenses. Eye examinations were performed on the first day (CL baseline), 2nd week, and 4th week of wearing the lenses. In addition, subjects completed the VBP and visual quality questionnaire again at the end of the examination. Single-vision contact lenses (Lens 1) increased accommodative lag, negative relative accommodation, and distant and near vergence; however, vergence facilities, accommodative facilities, heterophoria, and the comfort and posture balance dimensions in the VBP questionnaire were improved. Progressive contact lenses (Lens 2) reduced the lag of accommodation and near vergence; in addition, vergence facilities and accommodative facilities were also improved. Bifocal contact lenses (Lens 3) affected negative and positive relative accommodation, but vergence facilities and accommodative facilities also progressed. Furthermore, both progressive (Lens 2) and bifocal (Lens 3) contact lenses enhanced overall visual behavioral performance. In terms of visual quality, single-vision contact lenses (Lens 1) were the most comfortable, progressive and bifocal contact lenses reduced distant visual acuity and stability, progressive contact lenses (Lens 2) had more complaints about halos at night, and bifocal contact lens (Lens 3) users were more likely to have double vision. Compared with single-vision contact lenses, progressive and bifocal contact lenses relaxed accommodation, reduced the lag of accommodation, and improved visual behavioral performance. Although the vergence function showed a significant change, it did not show worse trends when wearing contact lenses. Contact lenses with different optical designs have a great influence on binocular vision and visual behavioral performance.