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1.
2.

Purpose

The aim of this work was to investigate the locus and extent of vitronectin (Vn) deposition on ex vivo contact lenses and to determine the influence of wear modality together with surface and bulk characteristics of the lens material.

Methods

The quantity and location of Vn deposition on the surfaces of contact lens materials was investigated using a novel on-lens cell attachment assay technique.

Results

Vn mapping showed that deposition resulted from lens-corneal interaction rather than solely from the tear film. Higher cell counts on the posterior surface of the lenses were determined in comparison to the anterior surface. Overall gross Vn deposition was greater for high water content-low modulus materials (117 ± 4 average cell count per field) than low water content-high modulus materials (88 ± 6 average cell count per field).

Conclusions

The role of Vn in plasmin regulation and upregulation is widely recognised. The findings in this paper suggest that the locus of Vn on the contact lens surface, which is affected by material properties such as modulus, is potentially an important factor in the generation of plasmin in the posterior tear film. Consequently, the potential for materials to affect Vn deposition will influence lens-induced inflammatory processes.  相似文献   

3.

Purpose

To investigate characteristics of the eyelid margins, meibomian glands and the tear film of contact lens wearers, and to determine whether these characteristics were related to symptoms of contact lens discomfort.

Methods

A cross sectional study was performed on thirty existing daily wear soft contact lens wearers (6 male; 24 female) with median age of 23 years (range 18–41). Eyelid signs and tear film characteristics were evaluated during a single visit and subjects completed the contact lens and dry eye questionnaire (CLDEQ-8) to evaluate ocular discomfort.

Results

Based on the CLDEQ-8 responses, subjects were classified as symptomatic (n?=?17) or asymptomatic (n?=?13). Grades of foam at meibomian gland orifices (3?±?1), expressibility (2?±?1) and quality of secretions (2?±?1), tear evaporation rate with (112?±?54?g/m2/h) or without (88?±?45?g/m2/h) contact lens wear, fluorescein tear breakup time (8?±?2 seconds) and tear lipid layer thickness (45?±?17?nm) were significantly associated with symptoms of discomfort in symptomatic lens wearers only (r2?>?0.45; p value?<?0.05). Upper lid-wiper epitheliopathy, meibomian gland acini reflectivity and tear meniscus height showed significant correlations with comfort scores in both symptomatic and asymptomatic contact lens wearers (p?<?0.05). A greater number of Demodex mites was also observed in the upper eyelid of symptomatic lens wearers (2?±?1) compared to asymptomatic lens wearers (0?±?0; p value?=?0.042).

Conclusions

Morphological irregularities of the meibomian glands and alterations to tear film secretions that affect tear evaporative dynamics were associated with symptoms of discomfort amongst the symptomatic lens wearers.  相似文献   

4.

Purpose

To assess the effects of two weeks of regular phospholipid liposomal spray application on lipid layer grade, tear film stability, subjective comfort, visual acuity, and lipid deposition in silicone hydrogel contact lens wearers.

Methods

Thirty-one existing contact lens wearers were enrolled and fitted with two week planned replacement silicone hydrogel contact lenses (Acuvue® Oasys®) in a prospective, randomized, paired-eye, investigator-masked trial. A phospholipid liposomal spray (Tears Again®) was applied to one eye (randomized) four times daily for two weeks. LogMAR high contrast visual acuity (VA), low contrast glare acuity (LCGA), non-invasive tear film break-up time (NIBUT), and lipid layer grade (LLG) were measured at baseline and day 14, in both treated and control eyes. Subjective comfort relative to baseline, and spectrofluorophotometric assessment of contact lens surface lipid deposition were also assessed on day 14.

Results

All measurements did not differ at baseline between treated and control eyes. Lipid layer thickness and tear film stability were increased on day 14 in treated eyes (all p < 0.05), but not in control eyes (all p > 0.05). A greater proportion of participants reported improved comfort in the treated eye relative to the control eye (p = 0.002). There were no significant differences in visual acuity or in contact lens surface lipid deposition, between treated and control eyes, on day 14 (all p > 0.05).

Conclusion

The phospholipid liposomal spray increased tear film stability, lipid layer thickness and subjective comfort in silicone hydrogel contact lens wearers, without adversely affecting visual acuity or contact lens surface lipid deposition.  相似文献   

5.

Purpose

Contact lens discomfort remains poorly understood, not least due to lack of associations between clinical signs and symptoms. This study aimed to explore the relationships between osmolarity, comfort and lid wiper epitheliopathy in contact lens wear.

Methods

Twenty subjects participated in a randomized, cross-over study where comfilcon A and lotrafilcon A lenses were each worn for 10 days separated by a 7 days washout period. Tear and contact lens osmolarity, ocular symptoms including comfort, tear stability and production, and lid wiper epitheliopathy were measured.

Results

Comfort and tear stability decreased and upper lid wiper staining and foreign body sensation increased with lens wear. These were not affected by lens type. A reduction in tear production was seen after 10 days of comfilcon A lens wear. High proportions of lid wiper epitheliopathy were observed at the upper (range 65%–85%) and lower (range 90%–100%) lid margins. Tear and contact lens osmolarity were unaffected by lens wear or type. Contact lens osmolarity was associated with comfort (r = 0.45, p = 0.009). Tear osmolarity moderately correlated with tear stability (r = ?0.53, p = 0.014) and tear production (r = ?0.44, p = 0.012) but not with lid wiper staining.

Conclusions

A relationship between comfort and contact lens osmolarity and between tear osmolarity and tear stability and production were found, however, this study was unable to demonstrate an association between comfort and tear osmolarity or lid wiper epitheliopathy. Further studies using contact lenses with a wider range of comfort responses are warranted to investigate these associations further.  相似文献   

6.

Purpose

To introduce a method for estimation of the rigid gas-permeable contact lens (RGP) movement.

Materials and methods

Videos captured from normal blinking of keratoconus patients while wearing RGP lenses were used for this study. The videos are recorded using the CCD camera of a smart phone attached to the eyepiece of the slit lamp. The algorithm starts with extracting two frames of the video related to the highest and lowest positions of the lens during blinking, followed by an appropriate edge detection method. In the next step circular Hough transform is used to find the center of lens and to segment it in each image. Finally the lens movement is estimated by measuring vertical displacement of the lens center between these two frames.

Results

Mean and standard deviation of the difference between real movement and results of the algorithm for 20 cases are ?8.66% and 10.71% respectively. The results are highly correlated with Pearson coefficient 0.986?P?<?0.001. Bland-Altman plot with 95% levels of agreement (LoA) shows an agreement between exact manual measurement method and the proposed algorithm.

Conclusion

The proposed algorithm shows a relatively high accuracy as the first attempt and compared to the routine qualitative visual estimation. Considering the importance of the lens movement, although this system was not tested on a series of RGP fitting patients yet, semi-automatic measurement may potentially help practitioners decide the appropriate RGP lens fit and reduce the fitting time.  相似文献   

7.

Purpose

To evaluate the tolerability of and subject and investigator satisfaction with delefilcon A (DAILIES TOTAL1®) daily disposable contact lenses in first-time contact lens wearers.

Methods

This European multicenter, open-label, single-arm, two-week trial enrolled first-time contact lens wearers and fitted them with delefilcon A contact lenses. Assessments were made at dispensing and at Weeks 1 and 2. Subject-reported outcomes included comfort, quality of vision, convenience, and intent to purchase, which were ranked by agreement responses. Investigator-reported outcomes included slit-lamp biomicroscopy findings and lens fit satisfaction.

Results

Ninety-two subjects were included in the per protocol dataset. Mean scores at Weeks 1 and 2 for subject-reported quality of vision and ocular comfort were significantly higher with delefilcon A contact lenses than with the subjects’ habitual spectacles during the day, at the end of the day, and overall (all p?≤?0.02). Ninety-one percent of subjects reported that their study lenses were more comfortable than expected, 98% agreed that they were convenient to use, and 92% were interested in purchasing the lenses (all p?<?0.001). Investigators reported that study lenses had an acceptable fit in at least 97% of subjects.

Conclusions

Practitioners can expect favorable outcomes when transitioning first-time contact lens wearers from spectacles to delefilcon A daily disposable contact lenses.  相似文献   

8.

Aim

Retrospective analysis of different contact lens wearing groups suggests lens surface lubricity is the main factor influencing contact lens comfort. However, the examined commercially available contact lenses differ in material and design as well as surface properties. Hence this study isolates the contribution of lens surface properties using an ultra-thin coating technology.

Methods

Nineteen habitual contact lens wearers (21.6 ± 1.7years) wore formofilcon B soft monthly disposable contact lenses with and without coating technology modified surface properties for a month each in a randomised double-masked cross-over study.

Objective non-invasive

breakup time (NIKBUT), NIKBUT average and ocular redness (Jenvis grading scale) were evaluated (Keratograph 5M) after 1 week and 1 month of wear. Symptoms were assessed using the Contact Lens Dry Eye Questionnaire (CLDEQ-8); perceived vision quality and subjective lens comfort at insertion, mid-day and end of the day were rated with four Visual Analog Scales.

Results

Perceived visual quality (F = 5.049,p = 0.037), contact lens dry eye symptoms (F = 14.408,p = 0.001) and subjective lens comfort (F = 28.447,p < 0.001) were better for coated compared to uncoated lenses. The surface coating postponed the lens dewetting (F = 8.518,p = 0.009) and increased the pre-lens tear film stability (F = 5.626,p = 0.029), but bulbar (F = 0.340,p = 0.567) and limbal (F = 0.110,p = 0.744) redness were similar for both contact lenses. No parameter changed significantly between a weeks’ and months’ wear (p > 0.05). Lens surface wettability and ocular redness were not correlated to changes in symptoms (p > 0.05).

Conclusion

As previously hypothesised, enhancing the physical surface properties of a soft contact lens improves subjectively rated wearer comfort, which, in turn, should result in reduced contact lens discontinuation.  相似文献   

9.

Purpose

To review contact lens prescribing trends in Japan between 2003 and 2016.

Methods

An annual survey of contact lens prescribing trends was conducted each year between 2003 and 2016. Japanese ophthalmologists were asked to provide information relating to ten consecutive contact lens fittings between January and March every year.

Results

Over the 14 years of the annual survey, data from a total of 64,122 contact lens fits were returned by ophthalmologists. The mean age (±SD) of lens wearers was 30?±?13?years, and 68% were female. The proportion of rigid lens fits decreased over time, from 35.4% in 2003 to 14.7% in 2016. Across this period, daily disposable lens fits increased, representing 46% in 2016. The proportion of toric lenses and multifocal lenses gradually increased, from 6.6% and 1.9% to 12.3% and 5.8%, respectively. Silicone hydrogel material use grew from 0% to 43.2%, while mid and low water content lens materials declined from 54.1% and 28.2% to 36.1% and 8.3%, respectively. Multi-purpose lens care solutions dominated the market over the 14?year survey period.

Conclusions

This survey has revealed prescribing trends and preferences in Japan over the past 14 years, with the main changes observed being a decrease in rigid lens use and an increase in the use of silicone hydrogel materials and daily disposable lenses.  相似文献   

10.

Background

Despite findings that contact lens wear for vision correction provides better quality of life than spectacles, contact lens use in developing countries is low. This study evaluated knowledge, usage and barriers associated with contact lens wear among spectacle wearers in Cape Coast, Ghana.

Method

A cross-sectional survey using a structured questionnaire was conducted on an adult population of spectacle wearers to assess their knowledge of contact lens wear for vision correction. The participants were proportionately sampled from three eye clinics in the Cape Coast Metropolis, Ghana. Questionnaires were either self-administered or completed with the help of a research assistant.

Results

Of the 422 participants, only 147 (34.8%) knew of contact lens wear for vision correction. The proportion of spectacle wearers reporting history of contact lens wear was 14 (3.3%). Barriers to contact lens wear reported were satisfaction with vision through spectacles 102 (25.0%), lack of adequate information 111 (27.2%), fear of side effects 94 (23.0%) and cost 78 (19.1%). The younger adults and those with higher number of changes of spectacles were more likely to know of contact lenses.

Conclusion

Knowledge and usage of contact lenses among spectacle wearers was low. Contact lens education and demonstration of visual performance through fitting of trial contact lenses on potential candidates may help overcome barriers to contact lens wear.  相似文献   

11.

Introduction

Scleral contact lenses are increasingly becoming accepted as the method of choice for visual correction of the irregular cornea. As such, cases have surfaced which demonstrate complications arising from mini-scleral lenses. Identification of these issues and adjusting fitting techniques accordingly is necessary for reducing the risks associated with mini-scleral lens wear.

Case report

A 58?year old Caucasian female was referred for rigid gas permeable contact lens fitting for correction of right irregular astigmatism post penetrating keratoplasty. After four months of successful mini-scleral contact lens wear, the patient experienced a graft rejection episode and treated accordingly, then refit with a new mini-scleral lens. Five months after the lens refit, the patient presented with complaints of hazy vision, and a diagnosis of lens-induced corneal oedema made.

Discussion

Increased awareness of the potential complications of mini-scleral lenses is necessary to encourage and enforce mini-scleral lens fitting techniques that meet the requirements of minimum vault but adequate protection of the compromised cornea.  相似文献   

12.

Purpose

To assess the prevalence and general knowledge of contact lens wearers among college students in Chengdu, a metroplolitan of Chinaand find out the routine habits of use and hygienic conditions when wearing contact lenses.

Method

The questionnaire was distributed to 1,600 ametropic participants who were from 8 different universities. Data about demographics, general contact lens handling habits, personal attitudes, hygiene behaviors and eye health conditions were collected. We made the analysis ofthe demographics and wearing of contact lenses. Possible reasons for behaviors related to the care of contact lenses were analyzed.

Results

The prevalence of contact lens use was 19.80%. Most users (82.15%) were females. An aesthetic effect was cited as the first reason for using (57.91%). The comfort of eyes was the first consideration (75.76%) when buying. To keep clean and use safe, 86.20% subjects washed hands before handling and 83.50% cleaned the lens carefully after removing. There was significant difference between males and females regarding the replacement of the solution (p = 0.014). 32.66% wears knew the removal of protein deposits. A total of 54.88% were not informed of the potential complications of contact lens. The incidence of ocular discomfort was 44.78%. Only 3.03% of the students paid regular visits to ophthalmic clinics.

Conclusion

The prevalence of contact lenses was relatively low in Chengdu. The wears had limited knowledge about using and careof contact lens. More education on standard lens wear and care should be provided to wearers.  相似文献   

13.

Purpose

To determine and compare the levels of surface versus bulk active lysozyme deposited on several commercially available hydrogel contact lens materials.

Methods

Hydrogel contact lens materials [polymacon, omafilcon A, nelfilcon A, nesofilcon A, ocufilcon and etafilcon A with polyvinylpyrrolidone (PVP)] were incubated in an artificial tear solution for 16?h. Total activity was determined using a standard turbidity assay. The surface activity of the deposited lysozyme was determined using a modified turbidity assay. The amount of active lysozyme present within the bulk of the lens material was calculated by determining the difference between the total and surface active lysozyme.

Results

The etafilcon A materials showed the highest amount of total lysozyme activity (519?±?8?μg/lens, average of Moist and Define), followed by the ocufilcon material (200?±?5?μg/lens) and these two were significantly different from each other (p?<?0.05). The amount of surface active lysozyme on etafilcon and ocufilcon lens materials was significantly higher than that found on all other lenses (p?<?0.05). There was no active lysozyme quantified in the bulk of the nelfilcon material, as all of the active lysozyme was found on the surface (1.7?±?0.3?μg/lens). In contrast, no active lysozyme was quantified on the surface of polymacon, with all of the active lysozyme found in the bulk of the lens material (0.6?±?0.6?μg/lens).

Conclusions

The surface and bulk activity of lysozyme deposited on contact lenses is material dependent. Lysozyme deposited on ionic, high water content lens materials such as etafilcon A show significantly higher surface and bulk activity than many other hydrogel lens materials.  相似文献   

14.

Aim

Contact lens induced dry eye affects approximately 50% of contact lens wearers. The aim was to assess the effects of Manuka (Leptospermum sp.) honey eye drops (Optimel, Melcare, Australia) on dry eye in contact lens wearers. The safety of the honey eye drops in contact lens wear and contact lens wearers’ compliance were also evaluated.

Design

Prospective, randomised, cross over study, examiner masked, pilot treatment trial.

Methods

Twenty-four participants aged 20 to 55 years with contact lens related dry eye were recruited and randomised to two treatment groups; 20 completed the study. One group used Optimel eye drops twice a day for two weeks followed by conventional lubricant (Systane Ultra, Alcon) therapy for two weeks; the other group completed the treatments in the reverse order. Before and after each treatment dry eye symptomology, ocular surface inflammation, and tear quantity and quality were assessed. Participants completed a daily log detailing their usage of treatments and any issues.

Results

Dry eye symptoms improved significantly after Optimel treatment. Patients with more severe symptoms at baseline showed a greater improvement in symptoms. No significant differences were observed in the objective signs of dry eye; presumably because of the short treatment duration. Seventy-five% of contact lens wearers reported good adherence to Optimel treatment and 95% reported no issues using this product.

Conclusions

Optimel Eye Drops reduce the symptoms of dry eye in contact lens wearers and are safe to use. A longer treatment period to assess the effect on clinical signs of dry eye is required.  相似文献   

15.

Purpose

This review summarises the way in which mechanical property measurements combined with clinical perception have influenced the last half century of materials evolution in contact lens development.

Methods

Literature concerning the use of in-vitro testing in assessment of the mechanical behaviour of contact lenses, and the mutual deformation of the lens material and ocular tissue was examined. Tensile measurements of historic and available hydrogel lenses have been collected, in addition to manufacturer-generated figures for the moduli of commercial silicone hydrogel lenses.

Results

The three conventional modes of mechanical property testing; compression, tension and shear each represent different perspective in understanding the mutual interaction of the cornea and the contact lens. Tensile testing provides a measure of modulus, together with tensile strength and elongation to break, which all relate to handling and durability. Studies under compression also measure modulus and in particular indicate elastic response to eyelid load. Studies under shear conditions enable dynamic mechanical behaviour of the material to be assessed and the elastic and viscous components of modulus to be determined. These different methods of measurement have contributed to the interpretation of lens behaviour in the ocular environment. An amalgamated frequency distribution of tensile moduli for historic and currently available contact lens materials reveals the modal range to be 0.3–0.6 MPa.

Conclusion

Mechanical property measurements of lens materials have enabled calibration of an important aspect of their ocular interaction. This together with clinical feedback has influenced development of new lens materials and assisted clinical rationalisation of in-eye behaviour of different lenses.  相似文献   

16.

Purpose

To investigate changes in tear and ocular surface of patients with keratoconus using rigid gas permeable contact lenses (RGPCL) and compare them against keratoconus patients who were not using lenses as well as a control group of healthy subjects.

Methods

24 keratoconus patients using RGPCL (Group 1) 22 patients who were not using lenses (Group 3) and 21 healthy subjects (Group 3) were included in the study. Subjective complaints about the subjects’ eyes have been investigated using the ocular-surface disease index (OSDI). After the control of best-corrected visual acuity, anterior chamber and fundus examinations were performed.

Results

Schirmer (p-value = 0.01) and tear break up mean comparison tests (p-value = 0.002) revealed significant differences across different groups but tear osmolarity analysis did not (p-value >0.05). Oxford and OSDI scores were compatible with Schirmer and tear break up test comparisons. (for both p-value = 0.001) Moreover, no statistical differences were seen in impression cytology measures between groups. (p-value >0.05)

Conclusions

The erosion in the tear film stability is in line with the erosion in the ocular surface epithelium. Taking into account the statistical indifference between the impression cytology measures across groups, the break up time differences may be attributed to the collagen destruction in tear.  相似文献   

17.

A statement of Significance

For the first time, this study shows that corneas that previous undergone orthokeratology treatment do not respond differently to LASIK compared with previous soft contact lens wear experience.

Purpose

To evaluate and compare the corneal morphology and visual outcomes of long-term soft and orthokeratology (OK) contact lens fitting in wearers undergoing corneal refractive surgery (LASIK) for myopia correction.

Methods

Sixteen (16) myopic patients wearing hydrophilic soft contact lens (SCL, n?=?8 subjects, control group) and OK (n?=?8 subjects, OK group) lenses who undergone LASIK were retrospectively evaluated. Preoperative fitting of contact lenses and one year postoperative were studied using Pentacam (Oculus, Inc. GmbH, Wetzlar, Germany). Corneal pachymetry and volume, corneal topography, anterior and posterior surface elevation data and the anterior surface aberrometry of the cornea were recorded and used for fitting.

Results

Age, refractive error and topographic parameters before LASIK did not showed statistically significant differences between the two study groups. LASIK post-treatment results showed identical changes in both control and OK groups and did not show significant differences in all the parameters evaluated. The changes on corneal parameters and HOA due to refractive surgery intervention were not different between Control and OK group (p?>?0.050).

Conclusions

Corneal changes due to OK treatment are reversible after its discontinuation. The present study gives an overview of how OK does not impair future LASIK surgery for the correction of myopia and does not influence the success/results of such intervention. These findings suggest that OK CL wear does not change corneal biomechanics and does not compromise a possible LASIK refractive surgery. Although this is a pilot study and there is a need of evaluate this results/changes in future studies.  相似文献   

18.

Purpose

To determine the antimicrobial activity of the melimine derived peptide Mel4 against Delftia, Stenotrophomonas, Elizabethkingia, Burkholderia and to investigate biocompatibility of Mel4 as an antimicrobial coating on contact lenses in animals and humans.

Methods

In vitro antimicrobial activity of Mel4 was determined against the four Gram negative bacteria by investigating growth curves for 24 h followed by viable counts to determine the minimum inhibitory concentration (MIC). Contact lenses were coated by covalently binding Mel4, characterized by amino acid analysis, and were investigated for changes in lens parameters. Safety of Mel-4 coated lenses were determined in a rabbit model of daily contralateral wear. A prospective, randomised, double-masked, contralateral, 1week daily wear human clinical trial was used to evaluate subjective responses and ocular physiology.

Results

Mel4 was active against all the bacteria tested (MIC50 ranged from 31–1000 μg ml?1) and produced an antimicrobial surface on contact lenses. Mel4-coating resulted hydrophilic surface without any significant change in contact lens parameters, and showed no signs of cytotoxicity or ocular irritation during rabbit wear. During human clinical trial, there were no differences between Mel4 coated and uncoated contact lenses in lens performance indicators and ocular signs such as corneal fluorescein staining. Mel4 and control uncoated lenses had no differences in ocular symptoms during lens wear.

Conclusion

Mel4 has achieved antimicrobial activity against variety of Gram negative bacteria that are often resistant to the action of cationic peptides and have been implicated in contact lens related adverse events. Mel4-coated contact lenses were safe to wear.  相似文献   

19.

Purpose

This study was designed to develop a novel technique called non-invasive keratograph dry-up time (NIK-DUT), which used an adapted corneal topographer, to analyse in-vitro contact lens surface dewetting and the effects of combinations of lenses and lens care solutions on dewetting.

Methods

Variables were assessed to optimise sensitivity and reproducibility. To validate the method, in-vitro dewetting of silicone hydrogel contact lenses (balafilcon A, comfilcon A, lotrafilcon A, lotrafilcon B and senofilcon A) was tested. All lens types were soaked in OPTI-FREE® PureMoist® Multipurpose Disinfecting Solution (OFPM) and Sensitive Eyes® Saline Solution. The mean NIK-DUT, defined as drying of 25% of the placido ring measurement segments (NIK-DUT_S25), was calculated for each lens/lens solution combination and a visual map constructed representing the time and location of the dry-up event.

Results

Optimal conditions for NIK-DUT measurement included mounting onto a glass stage with a surface geometry of r = 8.5 mm, e = 0, and measuring with high intensity red or white illumination. This method detected significant differences in contact lens dewetting with different lens soaking solutions. NIK-DUT_S25 for all lenses was longer when pre-soaked in OFPM versus saline. Visual analysis showed that dewetting of contact lenses was not uniform across surfaces and differed between test solutions.

Conclusions

NIK-DUT is suitable for detecting differences in dewetting among various contact lenses and lens-care combinations. NIK-DUT can quantify the dewetting of large areas of lens surfaces with little subjective influence. Lens care solutions containing surface-active wetting agents were found to delay surface dewetting of silicone hydrogel lenses.  相似文献   

20.

Purpose

To present a methodology for evaluating the optical quality of rotationally symmetrical contact lenses (CLs) from a single power profile.

Methods

Simulated rotationally symmetrical power profiles corresponding to different CLs designs (monofocal, two-zone center-near bifocal, and four-zone center-distance bifocal) were used to calculate the wavefront error profile by means of numerical integration. Then, each lens wavefront error profile was spun around the center to obtain the lens wavefront error surface. From the surface, monochromatic optical transfer functions (OTF), simulated images and the visual Strehl ratio based on the OTF (VSOTF) were obtained for different distances and pupil sizes (3 and 5.5 mm) after performing a through-focus.

Results

VSOTF variations, taking into account both vergence and pupil size, were presented for the three CLs designs. The monofocal design showed excellent optical quality only for far vision, whereas the bifocal designs exhibited good optical quality for far and near vision. Modulation transfer function (MTF) from each lens design, pupil size, and work distance agreed with the previous results.

Conclusions

The methodology presented here allows for a rapid and thorough assessment of the optical quality of rotationally symmetrical CLs by means of optical quality metrics, with a special interest in simultaneous image contact lenses. This methodology may be useful for choosing the most suitable lens for each subject’s visual demands.  相似文献   

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