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排序方式: 共有404条查询结果,搜索用时 31 毫秒
61.
Purpose
To report the symptoms and experiences associated with habitual hydrogel (Hyd) and silicone hydrogel (SiHy) contact lenses (CLs) among young adults and measure their association with age.Methods
Questionnaire responses from 699 Hyd and 183 SiHy wearers were analyzed to test the association of age with features indicating struggle with CL wear. Prevalence by age was compared between groups with Pearson's chi-square and within groups with Spearman's correlation coefficient.Results
Hyd and SiHy groups were similar for sex and age distribution. Diagnosis of dry eye increased with age in the Hyd wearers from 10.6% to 21.1% (18-24 vs. 30-35 years), but was approximately 19% in the SiHy wearers across age. Adverse environments caused more discomfort with Hyd than SiHy lenses and Hyd wearers’ discomfort increased with age (smoky (p = 0.0001), dry air environments (p = 0.002), after napping or sleeping (p = 0.004). More Hyd wearers considered discontinuation of CL wear with age, from 4.6% to 14.2% (18-24 vs. 30-35 years, p < 0.04), but the proportion remained steady at 9% across age for SiHy wearers (p = 0.46).Conclusions
From 18 to 35 years, hydrogel CL wearers reported increasing struggle with CL wear and more negative ratings compared to SiHy wearers. Older hydrogel CL wearers were also more likely to consider discontinuing CL wear compared with younger hydrogel or silicone hydrogel CL wearers in general. Young adult CL wearers should be routinely queried directly about specific aspects of CL wear in order to determine whether different lens types should be prescribed to avoid abandonment of CL wear. 相似文献62.
63.
Balamati Choudhury Sanjana Bisoyi Pavani Vijay Reddy Manjula S. R. M. Jha 《计算机、材料和连续体(英文)》2014,39(3):179-215
The terahertz spectrum of electromagnetic waves is finding its position in various applications of day to day life because of its unique properties, including the penetration through opaque materials. Naturally occurring materials in this range are rare due to the display of a natural breakpoint of both electric, and magnetic resonances in these materials. However recent advances in artificially engineered materials, which show resonance in this region are able to harness desirable properties in the terahertz region. In this paper, terahertz design and fabrication issues have been explored along with their applications. A brief review of metamaterial terahertz applications has been carried out including metamaterial absorbers, filters, modulators, switches, lenses, and cloaking structures. The various patterns of metamaterial unit cells are discussed elaborately along with the possibility of flexible active terahertz structures. 相似文献
64.
《Contact lens & anterior eye》2022,45(4):101472
PurposeAs presbyopia occurs, new visual demands create a need for clear vision at multiple distances. Many spectacle wearers adapt into progressive addition lenses (PAL) in order to see clearly at distance, intermediate, and near. A multifocal contact lens provides the ability to see at these same distances without the prismatic effects of a spectacle lens or the peripheral obstruction of a spectacle frame. No studies have been done to date comparing the effect of these types of presbyopic vision correction on a variety of tests of visual performance representative of everyday tasks.MethodsA battery of visual performance tasks were completed by subjects while wearing their habitual PAL spectacles. These subjects were then fit with a multifocal contact lens and wore lenses for 2 weeks or more before completing the tasks again. These functional vision tests included assessments of coincidence anticipation timing, peripheral search and hand-eye coordination, and dynamic visual acuity. Following functional vision testing, subjects completed a preference survey comparing both types of refractive correction while performing common activities of daily living.ResultsPerformance on the majority of the tests of visual performance were equivalent (P < 0.05) when comparing PAL spectacles and multifocal contact lenses. Survey results demonstrated a preference for multifocal contact lenses overall.ConclusionPAL spectacles are widely prescribed for presbyopic patients. The findings of this study suggest that in addition to providing excellent vision, multifocal contact lenses provide functional vision performance equal to PAL spectacle wear and patients may prefer them over PAL spectacles. 相似文献
65.
《Contact lens & anterior eye》2022,45(3):101452
PurposeTo report the use of a custom-designed, scleral contact lens (SL) in the treatment of pediatric patients.MethodsThe medical records of all patients under 15 years of age fitted with SL from March 2018 through February 2020 were retrospectively reviewed. Ophthalmic diagnosis, prior surgical intervention, lens wearing failures, and duration of lens use are reported.ResultsLenses were dispensed to 18 patients (24 eyes). Main indications for SL fitting were refractive error correction (n = 18: keratoconus (KCN), traumatic corneal scarring, corneal transplant status, and aphakia) and ocular surface protection and optimization (n = 6: neurotrophic keratitis and chronic blepharokeratoconjunctivitis). Patient age ranged from 16 months to 14 years (mean, 9.9 ± 3.5 years (mean ± standard deviation (SD)). Patients fitted for surface disease indications were significantly younger, 8.8 ± 2.5 years. The mean maximal keratometry reading in patients with keratoconus was 64.0 ± 12.6 diopters (D). In six eyes with advanced KCN (Kmax 71.8 ± 11.0 D) and three eyes with traumatic scarring, SL use obviated the need for keratoplasty. Fifteen patients (83 %) continued scleral lens wear with a mean follow-up period of 9.2 ± 7.4 months. Complications included one case of corneal graft rejection and one corneal abrasion associated with lens insertion.ConclusionsThe goals of SL fitting in pediatric patients are visual rehabilitation and ocular surface protection. Pediatric patients with advanced keratoconus and traumatic corneal scarring are most appreciative of the benefits of scleral lenses. The challenges associated with SL fitting and the training process did not preclude long-term SL wear. 相似文献
66.
《Contact lens & anterior eye》2014,37(3):196-202
PurposeTo evaluate the success rate of highly gas permeable scleral contact lenses (SCL) for visual rehabilitation after penetrating keratoplasty (PK), over a period of up to 9 years.MethodsA total database of 31 consecutive patient fitted with SCL between January 2004 and December 2009 was retrospectively reviewed. Demographic data, etiology prior to lens fitting, visual outcomes, follow up time and complications were analyzed.ResultsAll eyes were fitted due to inadequate spectacle-corrected vision after successful penetrating keratoplasty or failure of other contact lens modalities. Out of 31 patients fitted, 28 (33 eyes) continue to wear SCL for periods between 0.5 and 8.8 years. The mean duration of follow-up after contact lens fitting was 5.2 ± 2.2 years. The mean age of corneal graft was 17.6 ± 11.4 years (range 4.3–42), and the mean interval between PK and initial contact lens fitting was 12.2 ± 10.7 years (range 0.7–36.0). The average steepest keratometry of our cohort was 55.0 ± 7.5 diopter (D) and the refractive astigmatism was 8.0 ± 4.4 D. The mean contact lens corrected visual acuity (BCVAcl) was 0.78 ± 0.25 (range 0.3–1.2). Twenty-three (82%) patients achieved a functional vision of 0.5 or more.During the studied period, ten (30.0%) eyes presented at least one graft rejection episode and two eyes (6%) had an episode of microbial keratitis. Corneal transplants of 20 years or more show a higher rate of refits due to ectasia recurrence.ConclusionsScleral lenses should be considered as lens of choice in eyes with complex corneal geometry, as besides visual rehabilitation, their use may delay or prevent further surgical involvement. 相似文献
67.
Patient-related barriers to Rigid Gas Permeable (RGP) lens wear among keratoconus patients in Jordan
Purpose
To assess potential patient-related barriers to rigid gas permeable (RGP) lens wear for vision rehabilitation in a sample of keratoconus (KC) patients in Jordan.Methods
Barriers for RGP contact lens wear among KC patients were discussed and specified by a focus group which consisted of five optometrists who are involved in contact lens practice. The focus group addressed potential barriers for RGP lens wear from the patient’s perspective. The identified barriers were then used to design the final questionnaire used in the study. The questionnaire consisted of 8 questions which ask the participant to rate, within a 5-points scale (1: strongly disagree to 5: strongly agree), how each suggested item is considered a barrier for RGP lens wear.Results
204 KC patients (86 females, 118 males) were involved in a semi-structured interview to answer the questionnaire. The average age of participants was 30.85 (±8.74) years old and ranged from 18 to 62 years. The average age of diagnosis of KC (± standard deviation) is 21.96 (±7.22) years old with a range of 12–52 years. All participants reported that they had never tried RGP lenses for their vision rehabilitation; however, other management options were reported such as glasses, keratoplasty, collagen cross linking and Intacs. The mean score of total barriers to RGP wear was high at 3.8 (±0.4) (out of 5). The major identified barriers were: lack of awareness of the benefits of RGP lenses, fear of possible lens complications, lack of medical insurance and high cost of the lens.Conclusions
The study reveals that several barriers were identified as prevalent. Consequently, there is an imperative need to adopt better planning strategies for management protocol of KC in order to assure best eye care service for KC patients in Jordan. 相似文献68.
Jennie Diec Thomas Naduvilath Daniel Tilia Eric B. Papas Percy Lazon de la Jara 《Contact lens & anterior eye》2017,40(6):367-381
Purpose
To describe a ranked symptoms scale (RSS) discriminating subjective responses in contact lens (CL) wear in various situations.Method
Forty experienced clinical trial participants were interviewed for their perceptions of ocular comfort scales, resulting in a numerical RSS. For further evaluation, 20 CL wearers enrolled into a prospective, randomised, crossover trial. Two silicone-hydrogel CLs and a lens care solution (LCS) [Combinations A & B] were selected based on prior performance identifying best/worst combinations for end-of-day comfort. The RSS and a numerical rating scale (NRS) were administered at two time-points (insertion/removal) on alternating days for 6 days.Results
Both NRS and RSS showed acceptable internal consistency for comfort, vision and handling (Cronbach alpha = 0.71 for both scales) and similar repeatability for comfort and handling (coefficients-of-repeatability within 0.1 and 0.2 units, respectively, for each scale). The NRS and RSS discriminated differences between combinations for comfort (p ≤ 0.031) and vision (p ≤ 0.026) at both time-points. Additionally, the RSS showed lens/edge awareness influenced discomfort the most, ranking higher at insertion (p = 0.038) and higher for Combination-B at both time-points (p ≤ 0.002). Symptoms of dryness and tired eyes increased for both combinations at removal (p < 0.02). The RSS also showed haziness and blurred distance vision influenced vision dissatisfaction with Combination-B at lens removal (p ≤ 0.038) while eye strain/headache increased for both combinations by time of removal (p ≤ 0.013).Conclusions
The RSS is able to discriminate subjective responses between combinations and time-of-day. The RSS’s ability to rank symptoms may be a useful tool in understanding perceptions of discomfort or dissatisfaction with CL wear. 相似文献69.
《Contact lens & anterior eye》2022,45(1):101521
PurposeThe aim of this review was to evaluate the evidence on quality-of-life outcomes of long-term contact lens wear.MethodsA search for original articles that used validated measures to evaluate patient-reported outcomes (PROs) in long-term (≥2 years) contact lens wearers was conducted in Medline Ovid, PubMed, Scopus, Web of Science, Cochrane, CINAHL, and PsycInfo databases. The information including PRO measure (name, type, content) and key quality-of-life outcomes findings were extracted.ResultsSeven articles that used 4 PRO measures to evaluate quality of life outcomes of long-term contact lens wear met the inclusion criteria. The median (range) number of contact lens wearers in these studies was 116 (31–247). The studies were conducted in 4 countries: USA, Spain, China, and Russia. All studies were conducted in myopic populations. None of the studies provided information on psychometric properties, validity and reliability of the PRO measures used. Five studies were conducted in children of which 3 studies evaluated PROs of myopia control contact lens wear. The studies reported that contact lens wear, including myopia control lens wear, was an effective method of refractive correction in children and adults in the long term in PRO-perspective, and resulted in a better quality of life status than with glasses. However, long-term dry eye and discomfort related symptoms were reported.ConclusionOverall, contact lens use improved quality of life status in children and adults. More research is required to better understand the long-term quality-of-life outcomes of contact lens wear. 相似文献
70.