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1.
Ophthalmologie ; 120(4): 400-405, 2023 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-36251042

RESUMO

BACKGROUND: Small incision lenticule extraction (SMILE) is popular among young myopic adults for long-term correction of myopia; however, the excessive axial lengths of myopic eyes and the associated risks for more serious eye diseases later on remain with surgical correction of the refractive error. These risks are greater the higher the myopia is. Are patients well informed about this and to what extent does further eye growth occur even after SMILE? MATERIAL AND METHODS: Myopic young adults who underwent binocular SMILE before 2019 were given the opportunity to have their eyes examined at a follow-up visit (biometry using IOL-Master 700 [Zeiss, Oberkochen, Germany], subjective refraction, examination of the anterior and posterior segments of the eye using the slit lamp) and to participate in a survey. Patients with a preoperative axial length ≥ 25.5 mm and a preoperative axial length < 25.5 mm (high myopia) were statistically evaluated separately. RESULTS: A total of 44 patients (age 30.39 ± 2.39 years) appeared at the visit and the SMILE was 3.18 ± 0.82 years ago: The spherical equivalent at the follow-up visit was -0.05 ± 0.21 dpt in the weaker myopes and -0.18 ± 0.23 dpt in the high myopes. Of the respondents 27% estimated that SMILE would reduce the risk of retinal detachment and cataract, with 80% of high myopes underestimating the individual risk of retinal detachment. Also, 57% said they would not see an ophthalmologist until within 1 week if they had symptoms consistent with acute retinal detachment, and only 27% would go to an emergency room immediately. In general, 59% reported having normal health awareness and 41% reported going for annual ophthalmological check-ups. CONCLUSION: The collected axial lengths and refractions show no relevant change in the eyes regarding progression of myopia; however, the patients' statements in the survey point out that most patients are not aware of the risk of serious eye diseases (retinal detachment, cataract). Therefore, repeated risk education and close postoperative care are needed, especially in preoperatively highly myopic patients.


Assuntos
Catarata , Miopia , Descolamento Retiniano , Adulto , Humanos , Adulto Jovem , Miopia/cirurgia , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Acuidade Visual
2.
Optom Vis Sci ; 99(10): 750-757, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36095059

RESUMO

SIGNIFICANCE: The dewetting process of contact lenses (CLs) is a result of material and solution properties as well as environmental factors. This article describes an investigational approach to observe and describe dewetting characteristics of different CL material and solution combinations. PURPOSE: This study aimed to determine the in vitro dewetting characteristics of various daily disposable CLs that were assessed using a noninvasive keratograph dewetting procedure (noninvasive keratograph dry-up time). In vitro dewetting data of the same CL materials soaked in saline solution and artificial tear solution (ATS) were measured to determine additional dewetting characteristics. METHODS: Noninvasive keratograph dry-up time was measured for six different soft CL materials and three different test conditions, in their specific blister solution, after exposure to saline and an ATS. Twenty CLs of each solution/material combination were assessed after an 8-hour soaking, during a 180-second dewetting observation, and the results were expressed by area under the curve values. RESULTS: Fastest dewetting occurred for all materials when measured out of saline, indicated by the highest averaged area under the curve value of 9243.3 ± 38.3 over all lens materials. Slower dewetting was detected for all materials when measured out of their specific blister solution (7755.9 ± 37.1) and out of ATS (7988.8 ± 40.0). Intragroup results were statistically significantly different for all solutions showing the smallest differences within the ATS group ( P < .001, Kruskal-Wallis test). CONCLUSIONS: A pure saline thin film is not an ideal representation of a complex tear film layer of a healthy human because it lacks any evaporative protection by a lipid layer. The use of an ATS, which more likely mimics the natural tear film, allowed in this experimental in vitro project to decrease the gap to the in vivo field. In vitro dewetting information in connection with the blister solution allows only a theoretical conclusion about the initial lens wear after lens insertion.


Assuntos
Lentes de Contato Hidrofílicas , Vesícula , Humanos , Lipídeos/análise , Lubrificantes Oftálmicos , Solução Salina , Lágrimas/química
3.
BMJ Open Ophthalmol ; 7(1): e000971, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464151

RESUMO

Objective: Visual performance and short-term tolerability of different designs of myopia correcting options, including therapeutically relevant bifocal contact lenses (CL) and spectacle lenses with 'defocus incorporated multiple segments (DIMS)' technology were compared. Methods and analysis: In myopic volunteering subjects (n=8; spherical equivalent range: -1 to -7 D) visual acuity (VA) using Landolt C and contrast sensitivity (CS) using contrast C were assessed at three different gaze positions (-22° nasal, +22° temporal and 0° central), corresponding to a gaze through the DIMS area or the clear area of the DIMS lens design, respectively, after short-term wear of each of single vision spectacle lenses (SV), DIMS spectacle lenses (DIMS), monofocal soft CL and centre-near multifocal soft CL (MCL). Also, CS was assessed under photopic and mesopic light conditions with and without glare using sinusoidal gratings at 1.5, 3, 6, 12 and 18 cpd. Results: Mean VA (Landolt C) was -0.12 to -0.10, -0.05 and 0.10 logMAR (SV, DIMS, CL, MCL) at central gaze (0°). At nasal gaze (-22°), VA differed by 0.12, 0.33, 0.05 and 0.01, and at temporal gaze (+22°) by 0.05, 0.26, 0 and -0.08 compared with central gaze values. Mean CS (Contrast C) was 1.74, 1.73, 1.69 and 1.61 logCS (SV, DIMS, CL, MCL) at central gaze at nasal gaze, CS differed by -0.02 to -0.13, -0.01 and -0.01, and at temporal gaze by -0.02 to -0.16, -0.01 and +0.06 compared with central gaze values. Conclusion: When compared with SV, MCL leads to a general decrease in VA and CS, while DIMS did not differ from SV at straight gaze (0° gaze). With DIMS, VA and CS are decreased to a similar level as with the MCL, but only at nasal and temporal gaze.


Assuntos
Visão de Cores , Lentes de Contato Hidrofílicas , Miopia , Humanos , Miopia/diagnóstico , Projetos Piloto , Testes Visuais
4.
Ocul Surf ; 24: 93-99, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35134570

RESUMO

PURPOSE: Meibomian glands (MG) are now easily imaged via clinical meibography machines. The purpose of this work was to explore the utility of the known MG morphology metrics for predicting dry eye disease (DED) in contact lens (CL) wearers. METHODS: Successful and previous CL wearers were recruited. DED was diagnosed if the participant's worst eye had a reduced tear meniscus height (TMH) of <0.2 mm or non-invasive tear break-up time (NITBUT) of <10 s and a Standardized Patient Evaluation of Eye Dryness (SPEED) score >5.0. Meibography was performed and images were subjectively graded by two examiners for the following MG characteristics: distorted, tortuous, hooked, abnormal gap, overlapping, fluffy areas, tadpoling, thinned, thickened, ghost, no extension to lid margin, shortened and dropout (atrophy). DED diagnostic ability of each metric was determined with receiver operating characteristic (ROC) analysis. RESULTS: A total of 112 participants were recruited, with 18.8% having DED and 60.7% being female. The only MG morphology metrics that were marginally predictive of DED were thickened upper eyelid MGs (p = 0.046), thickened mean upper plus lower eyelid MGs (p = 0.007), and atrophy of upper eyelid MGs (p = 0.043); however, none of these metrics reached a meaningful area under the curve in ROC analysis (all <0.70). CONCLUSION: While abnormal MG morphology is likely suggestive of DED in CL wearers, none of the MG morphology metrics evaluated alone in this study had clinically meaningful predictive value for detecting DED in this group of current and previous CL wearers.


Assuntos
Lentes de Contato , Síndromes do Olho Seco , Doenças Palpebrais , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/etiologia , Doenças Palpebrais/diagnóstico , Doenças Palpebrais/etiologia , Feminino , Humanos , Masculino , Glândulas Tarsais/diagnóstico por imagem , Lágrimas
5.
Optom Vis Sci ; 98(11): 1270-1278, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34510145

RESUMO

SIGNIFICANCE: Ultraviolet (UV) and visible light transmittance of soft contact lenses (SCLs) was measured. A significant difference in UV transmittance has been found between SCLs with a positive and negative back vertex power (BVP). It can be shown that thicker SCLs absorb more UV radiation. PURPOSE: This study aimed to determine UV and visible light transmittance of different SCLs with and without UV protection filters. METHODS: Twenty-one lens brands were investigated in the BVP range of -12.00 to +6.00 D. Three SCLs were measured per BVP 25 times. Three hundred thirty-nine SCLs with UV filter (stenfilcon A, somofilcon A, narafilcon A, senofilcon A, senofilcon C, etafilcon A, nesofilcon A) and 489 SCLs without UV filter (delefilcon A, lotrafilcon A, lotrafilcon B, comfilcon A, balafilcon A, samfilcon A, asmofilcon A, nelfilcon A, omafilcon A, hilafilcon B, ocufilcon D, hioxifilcon A, omafilcon B) have been examined. The measurement setup was created according to ISO 18369-3. RESULTS: All UV-absorbing labeled test SCLs meet UV protection class 2. senofilcon A, senofilcon C, and narafilcon A meet the higher UV protection class 1 level. A statistically significant difference in UV transmittance (280 to 380 nm) has been found between SCLs with a positive BVP (+1.00 to +6.00 D) and SCLs with a negative BVP (-1.00 to -12.00 D), both without (P = .04) and with UV filters (P = .02). CONCLUSIONS: With the ISO-conforming, diopter-independent measurement setup, the UV-absorbing test contact lenses that meet the current international standards, regardless of their BVP, were identified. Lenses with increased center thickness absorb more UV radiation. Further studies may use a modified measurement setup with a larger aperture than 10 mm. It would also be worthwhile to examine the UV absorption of the contact lens over the complete corneal area and limbal area because UV radiation may damage inner ocular tissues like the crystalline lens as well as limbal stem cells.


Assuntos
Lentes de Contato Hidrofílicas , Cristalino , Córnea , Humanos , Luz , Raios Ultravioleta
6.
Clin Optom (Auckl) ; 12: 203-211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244285

RESUMO

PURPOSE: The primary objective of this study was to evaluate the in vivo pre-lens non-invasive drying-up time of two types of daily disposable contact lenses (DDCLs) after 12 hours of wear. METHODS: This prospective, randomized, single-center, cross-over pilot study evaluated 31 subjects aged 18-44 years with normal eyes and good tear film stability who were adapted current soft contact lens wearers. Subjects wore nelfilcon A and stenfilcon A DDCLs for 12 hours each on two different days. Non-invasive video keratography drying-up time (NIK-DUT) videos of each eye were recorded 12 hours after lens insertion for about 25 seconds, with a 5-minute tear film recovery time allowed between video recordings of the right and left eyes to avoid bias. Post-blink time required to reach 15% distortion of the projected rings and the speed of break-up at 15 seconds post-blink were measured at each time point and on-eye wettability was determined by ring mire projection under white light illumination. RESULTS: Mean time to reach 15% ring distortion was similar for nelfilcon A (19.25±3.20 sec) and stenfilcon A (20.24±3.02 sec) DDCLs but varied highly among subjects. The mean speed of break-up at 15 sec post-blink was 0.3±0.38% distortion/sec (95% confidence interval [CI] 0.138-0.365% distortion/sec) for nelfilcon A and 0.2±0.23% distortion/sec (95% CI 0.048-0.279% distortion/sec) for stenfilcon A DDCLs. CONCLUSION: Multifunctional topography allowed the objective evaluation of in vivo pre-lens tear film stability using ring mire projection. This dynamic method was simple, fast and non-invasive, enabling measurements of NIK-DUT and evaluating wettability over a large area, greater than the optical zone of the contact lens surface, for the entire inter-blink interval.

7.
Optom Vis Sci ; 97(8): 565-572, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32769842

RESUMO

SIGNIFICANCE: Lotrafilcon B lenses packaged in and cared for with block copolymer-containing (polyoxyethylene-polyoxybutylene; EOBO) lens care solutions resulted in lower cholesterol extraction than each of the habitual silicone hydrogel lens/multipurpose solution (MPS) regimens tested. PURPOSE: This study aimed to compare the extracted cholesterol of lotrafilcon B lenses packaged in and cared for with EOBO-containing lens care solutions with the extracted cholesterol of habitual silicone hydrogel lenses cared for with MPS not containing EOBO. METHODS: In this prospective, randomized, observer-masked parallel study, habitual wearers of senofilcon C, senofilcon A, comfilcon A, and samfilcon A contact lenses using a non-EOBO MPS were randomized 1:1 to lotrafilcon B lenses packaged in and cared for with EOBO-containing solutions or to their habitual lenses and MPS. Subjects randomized to lotrafilcon B were further randomized to one of two EOBO-containing lens care solutions, OPTI-FREE PUREMOIST or CLEAR CARE PLUS with HydraGlyde (Alcon Laboratories, Inc., Fort Worth, TX). A subset of right eye lenses was collected after wear, and total cholesterol was extracted and measured using a fluorometric enzymatic assay. RESULTS: Of 143 lenses analyzed, 95 were from subjects randomized to their habitual lenses/MPS and 48 to lotrafilcon B + EOBO lenses plus CLEAR CARE PLUS with HydraGlyde or OPTI-FREE PUREMOIST. The mean amounts of cholesterol extracted from lotrafilcon B + EOBO lenses cared for with CLEAR CARE PLUS with HydraGlyde (0.28 ± 0.18 µg/lens) and OPTI-FREE PUREMOIST (0.28 ± 0.48 µg/lens) were significantly lower than those extracted from senofilcon C (4.18 ± 3.25 µg/lens), senofilcon A (2.19 ± 2.69 µg/lens), comfilcon A (2.17 ± 1.47 µg/lens), and samfilcon A (2.07 ± 1.48 µg/lens) lenses used with MPS (P < .0001 each). CONCLUSIONS: Cholesterol sorption was significantly lower in wearers of lotrafilcon B lenses cared for with polyoxyethylene-polyoxybutylene-containing lens care solutions than in users of habitual silicone hydrogel lenses cared for with non-polyoxyethylene-polyoxybutylene MPS.


Assuntos
Colesterol/análise , Soluções para Lentes de Contato/química , Lentes de Contato Hidrofílicas , Hidrogéis/química , Elastômeros de Silicone/química , Silicones/química , Lágrimas/química , Adulto , Alcenos , Método Duplo-Cego , Feminino , Fluorometria , Humanos , Masculino , Polietilenoglicóis , Embalagem de Produtos , Estudos Prospectivos
8.
Clin Optom (Auckl) ; 12: 17-26, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184693

RESUMO

PURPOSE: To subjectively evaluate the in vivo tear film stability of three daily disposable contact lenses (DDCLs) using placido ring reflection at lens wear times of 5 mins and 8 and 12 hrs. PATIENTS AND METHODS: This prospective, randomized, observer-masked, 3-way crossover study evaluated 28 subjects with good tear film stability. In vivo tear film stability was assessed for three DDCLs (nelfilcon A, etafilcon A, omafilcon A) on three different days over 12 hrs of lens wear. Time to first distortion by non-invasive keratography drying-up time (NIK-DUTf) was assessed by reviewing the captured videos. Lens wettability was also graded subjectively by three investigators using a scale from 0 (no visible distortions) to 3 (distortions in more than one-third of the ring reflection zone). Medians were analyzed statistically. RESULTS: Mean NIKDUTf at 8 hrs was longer for nelfilcon A and shorter for etafilcon A and omafilcon A, but the differences were not significant. NIK-DUTf did not differ significantly among nelfilcon A, etafilcon A and omafilcon A DDCLs at all visits (p=0.36). Subjective wettability grades after 5 mins, 8 hrs, and 12 hrs differed significantly for etafilcon A (P <0.01) and omafilcon A (p < 0.01), but not for nelfilcon A (p = 0.05), DDCLs. CONCLUSION: Grading was sufficiently sensitive to differentiate the wettability performances of the three lens materials. Nelfilcon A maintained wettability over the wearing period, whereas etafilcon A material showed faster dewetting at 8 and 12 hrs than at 5 mins after lens insertion.

9.
Cont Lens Anterior Eye ; 43(4): 359-365, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32147391

RESUMO

PURPOSE: To introduce a novel in vivo method (Visual Acuity Dry Up; VADU) for testing the visual performance during the dewetting of the pre-lens tear film on a contact lens (CL). METHODS: Thirty-nine subjects were fitted with daily disposable CL (Nelfilcon A). Visual performance and dewetting characteristics of the pre-lens tear film were simultaneously assessed using a modified multifunctional topographer (Keratograph 5 M, OCULUS Optikgeräte GmbH, Wetzlar, GERMANY) and the Non-Invasive Keratograph Dry-Up Time (NIKDUT) method. Measures were taken after five minutes and eight hours of CL wear and included the Visual Acuity Dry-Up Time (VADUT; time between last blink and visual breakdown) and the Visual Acuity Dry-Up Area (VADUA; dewetted CL area at visual breakdown) at one (VA+0.1logMAR), two (VA+0.2logMAR) and three (VA+0.3logMAR) log units below maximal visual acuity (VA). RESULTS: Participants lost one, two or three log units of VA after 13.1 ± 17.4 s, 20.83 ± 21.81, 34.67 ± 29.11 (VADUT), corresponding to a dewetted CL area of 4.82 ± 6.64 mm², 9.5 ± 8.26 and 13.0 ± 8.68 (VADUA), respectively. Differences in VADUT und VADUA for all visual requirements were significant (all p < 0.05). VADUT and VADUA did not vary with CL wear duration (all p > 0.05). A median VA loss of one log unit occurred five seconds after the first dewetting. CONCLUSIONS: The novel VADU method can be used to analyze the role of the tear film stability on the visual performance during CL wear. Hereby, visual loss is quantified based on the threshold definition of the psychometric function.


Assuntos
Lentes de Contato Hidrofílicas , Piscadela , Humanos , Lágrimas , Transtornos da Visão , Acuidade Visual
11.
Cont Lens Anterior Eye ; 42(6): 646-651, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31229450

RESUMO

PURPOSE: To evaluate meibomian gland (MG) width and determine its impact on successful contact lens (CL) use and ocular health. METHODS: A five-site study was conducted by recruiting 18- to 45-year-old subjects who had dropped out of CLs because of discomfort. CL dropouts were compared to age- and sex-matched successful CL wearers. Right eyes were evaluated for tear break-up time, tear meniscus height, MG expressibility, meibum quality, and meibography. Central MG widths were evaluated with a custom MATLAB program. RESULTS: CL dropouts (n = 56) and successful CL (n = 56) wearers had similar grades for upper (p = 1.0) and lower (p = 0.22) MG atrophy, upper (p = 0.07) and lower (p = 0.89) MG tortuosity, and upper (p = 0.92) and lower (p = 0.97) MG widths. Upper eyelid MG widths were narrower than lower eyelid MG widths (p = 0.03). Upper and lower MG tortuosity (p < 0.001) and widths (p = 0.03) were associated, but not atrophy (p = 0.42). Lower eyelid MG widths were associated with MG expressibility (p = 0.01), but MG widths were not with any other factors. CONCLUSIONS: Successful CL wear does not appear to be clinically influenced by MG width or other measures of MG structural integrity. Lower eyelid MGs were wider than upper eyelid MGs and narrower lower eyelid MGs were associated with worse MG expressibility, suggesting that narrower MGs may produce abnormal meibum. Data also suggests that MG factors of both eyelids should be evaluated in practice.


Assuntos
Lentes de Contato/estatística & dados numéricos , Glândulas Tarsais/patologia , Adolescente , Adulto , Síndromes do Olho Seco/fisiopatologia , Feminino , Humanos , Masculino , Disfunção da Glândula Tarsal/fisiopatologia , Pessoa de Meia-Idade , Inquéritos e Questionários , Lágrimas/química , Adulto Jovem
13.
Cont Lens Anterior Eye ; 42(3): 318-324, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30538060

RESUMO

PURPOSE: Contact lens (CL) dropout is estimated to be approximately equal to the number of new wearers per year, resulting in virtually no growth in the global CL market. The purpose of this study was to determine ocular and CL factors associated with CL dropout. METHODS: This five-site study recruited subjects 18-45 years of age who had ceased CL wear within the past 6-12 months due to discomfort. Dropout subjects were compared to age- and sex-matched currently successful CL wearers. Each subject was administered a symptoms survey and a study-specific survey that queried general CL history and compliance. Clinical testing included non-invasive tear break-up time, tear meniscus height, blepharitis assessment, meibum quality and expression, and meibography. RESULTS: A total of 56 matched-pairs were recruited. Dry eye was found to significantly increase a subject's odds of dropping out of CLs. The odds of dropping out of CLs was also significantly increased with each worsening grade of upper or lower eyelid meibomian gland (MG) plugging, upper eyelid meibum quality, and upper eyelid MG tortuosity. No other factors analyzed increased a subject's odds of dropping out of CLs. CONCLUSIONS: CL dropout may be precipitated by underlying dry eye symptoms, though most dry eye signs, with the exception of MG structure and function, had minimal predictive value for CL dropout. Nevertheless, evidence suggests that practitioners should screen for and educate CL patients about the importance of maintaining healthy MGs, which may potentially allow them to maintain comfortable CL use and increase their CL longevity.


Assuntos
Lentes de Contato Hidrofílicas/efeitos adversos , Síndromes do Olho Seco/etiologia , Disfunção da Glândula Tarsal/etiologia , Pacientes Desistentes do Tratamento , Adolescente , Adulto , Síndromes do Olho Seco/diagnóstico , Feminino , Humanos , Masculino , Disfunção da Glândula Tarsal/diagnóstico , Pessoa de Meia-Idade , Cooperação do Paciente , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
14.
J Cataract Refract Surg ; 44(12): 1478-1481, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30392762

RESUMO

PURPOSE: To develop and evaluate a cataract quantification method using a swept-source optical coherence tomography (SS-OCT) device (IOLMaster 700). SETTING: Hanusch Hospital, Vienna, Austria. DESIGN: Prospective multicenter case series. METHODS: This study included patients with cataract in at least 1 eye. Two independent examiners performed Lens Opacities Classification System II (LOCS II) grading at the slitlamp independently. Corrected distance visual acuity, contrast sensitivity, and SS-OCT measurements were also performed. In addition, the phacoemulsification energy and time were recorded. To develop an objective SS-OCT-based cataract quantification system, all SS-OCT scans were segmented and the local pixel intensity unit of the lens was analyzed using Matlab's grayscale counting. The pixel intensity unit of the lens nucleus (OCT-based cataract quantification system score) was equated to the clinician's subjective nuclear opalescence grading. RESULTS: The study evaluated 186 eyes (113 patients). The correlation between the independent examiners' LOCS grading was good (0.91) (P < .01). The correlation between the LOCS grading and OCT-based cataract quantification system score was 0.86 for examiner 1 and 0.76 for examiner 2 (both P < .01). In 24 patients, phacoemulsification time, power, and energy; visual acuity; and contrast sensitivity were available and included in the study. The OCT-based cataract quantification system scores correlated significantly with phacoemulsification time (0.71) and energy (0.64) (both P < .01). CONCLUSIONS: Cataract density could be evaluated using an SS-OCT device, and the OCT-based cataract quantification system values correlated with the conventional LOCS II classification. Swept-source OCT measurements allowed quantification and documentation cataract density.


Assuntos
Catarata/diagnóstico , Cristalino/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Catarata/classificação , Catarata/fisiopatologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
15.
Cont Lens Anterior Eye ; 40(6): 394-400, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28935527

RESUMO

PURPOSE: Pilot study to investigate the feasibility of an axis-free correction approach of regular astigmatism using soft, bifocal contact lenses (CL). METHODS: The investigation covers an optical simulation and a pilot study for the assessment of visual performance (over refraction OR, monocular visual acuity VA). The power of the two zones was adjusted according to the power of the astigmatic meridians, individually. Subjective performance was assessed in 30 participants with a mean horizontal cylindrical component of J0=- 0.65±1.29 D (cylinder from -0.75 to -4.00 DC). OR and VA were measured directly after fitting the CL, after one hour and after 5days (3FUP). RESULTS: Evaluating the modulation transfer function, CL increased the Strehl ratio by 10% and the transferred spatial frequency was improved from 6.6 cpd to 21.3 cpd. Analysis of Sturm's interval revealed a residual astigmatism of DAst=0.73 D. OR revealed a statistically significant reduction of spherical error between baseline and all follow up (ΔM=-2.14 D, p<0.001) and between the J0 from baseline to 3FUP (ΔJ0=-0.46 D, p=0.04). Wearing the CL for 5days did not result in a significant difference of VA (ΔVA3FUP=+0.01 logMAR, p=0.99). CONCLUSION: Axis-free correction of astigmatism using bifocal CL resulted in reasonable performance based on computer simulation. Participants showed no clinically reduced visual acuity or contrast sensitivity. Further clinical studies are needed to show if this approach provides a good alternative to conventional astigmatic correction.


Assuntos
Astigmatismo/terapia , Simulação por Computador , Lentes de Contato Hidrofílicas , Sensibilidades de Contraste/fisiologia , Refração Ocular/fisiologia , Acuidade Visual/fisiologia , Adulto , Astigmatismo/diagnóstico , Astigmatismo/fisiopatologia , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Humanos , Masculino , Projetos Piloto , Testes Visuais
16.
Cont Lens Anterior Eye ; 40(6): 382-388, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28847466

RESUMO

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=8.5mm, 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.


Assuntos
Soluções para Lentes de Contato/farmacologia , Lentes de Contato Hidrofílicas , Topografia da Córnea/instrumentação , Dessecação/métodos , Molhabilidade/efeitos dos fármacos , Desenho de Equipamento , Humanos , Curva ROC , Reprodutibilidade dos Testes , Propriedades de Superfície
18.
Optom Vis Sci ; 92(9): e206-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26154690

RESUMO

PURPOSE: To determine associations for contact lenses (CLs) and meibomian gland atrophy in a matched-pair study. METHODS: Contact lens wearers (case) and age- and sex-matched non-contact lens (NCL) wearers with no history of CL use (control) were recruited for a multicenter study. All subjects were administered the Ocular Surface Disease Index questionnaire and a comprehensive battery of clinical tests (e.g., tear breakup time, bulbar and limbal redness, meibography, etc.) were performed. Upper and lower eyelid meibomian gland atrophy were graded with both digital meibography (percent gland atrophy) and visual meiboscore methods. Conditional logistic regression analyses were then used to determine relationships among CL use, meibomian gland atrophy, and ocular surface signs and symptoms. RESULTS: A total of 70 matched pairs were analyzed. The mean (± SD) age of the CL group was 30.6 (± 12.4) years, and that of the NCL group was 30.1 (± 12.2) years. The subjects were 63% female. The association between CL wear and meiboscore was not significant univariately, but the best-fitting multivariate regression model showed that higher meiboscores were associated with being a CL wearer (odds ratio [OR], 2.45) in a model that included eyelid margin erythema (OR, 0.25) and lissamine green staining (OR, 1.25). Percent gland atrophy was not associated with CL wear in regression analysis (p = 0.31). CONCLUSIONS: This study determined inconclusive associations with CLs and meibomian gland atrophy. This study also provided a comprehensive assessment of differences between CL and NCL wearers.


Assuntos
Lentes de Contato/efeitos adversos , Doenças Palpebrais/etiologia , Glândulas Tarsais/patologia , Adolescente , Adulto , Atrofia , Doenças Palpebrais/diagnóstico , Feminino , Humanos , Masculino , Inquéritos e Questionários , Adulto Jovem
19.
Coll Antropol ; 37 Suppl 1: 165-73, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23837239

RESUMO

To measure the corneal thickness and the depth of the precorneal tear film of contact lens wearers with keratoconus or keratoplasty and to reconfirm the identification and classification of the keratoconus with optical coherence tomography (OCT). The cornea and precorneal tear film of 123 eyes with keratoconus, of 39 eyes after keratoplasty and 8 eyes after LASIK were examined with an OCT (Zeiss Visante) and a keratograph (Oculus). Visual acuity was determined. The mean age of all patients was 42.7 years (sigma = 9). There were 35% female patients and 65% were male patients. The central corneal thickness of 123 eyes with keratoconus was 467 +/- 73 microm. The nasal and especially the inferior corneal periphery exhibit a 9% lesser thickness (426 +/- 83 microm). The cornea with keratoconus is thinner in the 90 degrees meridian, than in the 180 degrees meridian (p < 0.01). This could be a clinically relevant result for the reduction of astigmatism after keratoplastic surgery. The central corneal thickness of 39 eyes with keratoplasty was 555 +/- 65 microm. These eyes showed peripheral parts with even less thickness. The thickness of the precorneal tear film of 114 contact lens wearers with keratoconus was 89 +/- 42 microm in the horizontal meridian, 113 +/- 56 microm in the vertical meridian. All the comparative results in case of keratoconus, keratoplasty and the depth of the precorneal tear film had high statistical significance (p < 0.001). Optical coherence tomography is particularly suitable for the examination of eyes with keratoconus and keratoplasty. It delivers new insight into corneal thickness of eyes with keratoconus and keratoplasty.


Assuntos
Lentes de Contato , Córnea/patologia , Transplante de Córnea , Ceratocone/patologia , Tomografia de Coerência Óptica/métodos , Adulto , Feminino , Humanos , Ceratocone/diagnóstico , Masculino
20.
Graefes Arch Clin Exp Ophthalmol ; 249(6): 895-901, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21234587

RESUMO

BACKGROUND: We investigated the effects on intraocular pressure (IOP) and blood pressure (BP) of playing brass and woodwind instruments by monitoring IOP and BP in a representative group of professional musicians under a variety of common playing conditions. METHODS: IOP and BP measurements were recorded from 37 brass and 15 woodwind instrument players, before and after playing tones of low, middle and high frequency. We also measured IOP and BP before and during playing common exercises of 10 minutes duration, as well as after playing a sustained high-pitched tone, to test for changes in IOP under conditions of maximum effort. RESULTS: Playing tones on brass and woodwind instruments causes a temporary elevation in IOP and BP, depending on the tone frequency: brass instrument players showed a significant elevation after playing high and middle frequency tones (p < 0.0001) whereas woodwind instrument players showed a significant increase only for high frequencies (e.g., oboe, 17 ± 2.9 mm Hg to 21 ± 4.4 mm Hg; p = 0.017). Playing a typical exercise of 10 minutes temporarily increased IOP in both groups of musicians. Finally, playing a sustained tone of high pitch caused a significant elevation in IOP in brass instrument players only (16.6 ± 3.5 mm Hg to 23.3 ± 8.9 mm Hg; p < 0.0001). CONCLUSIONS: The temporary and sometimes dramatic elevations and fluctuations in IOP observed in this study, coupled with daily exposure to instrument play, puts professional wind instrument players at increased risk of developing glaucoma. Consequently, these musicians should be monitored for signs of glaucoma, especially those with co-existing risk factors.


Assuntos
Hipertensão/fisiopatologia , Pressão Intraocular/fisiologia , Música , Doenças Profissionais/fisiopatologia , Exposição Ocupacional/efeitos adversos , Hipertensão Ocular/fisiopatologia , Adulto , Pressão Sanguínea/fisiologia , Monitores de Pressão Arterial , Feminino , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Hipertensão Ocular/etiologia , Fatores de Risco , Tonometria Ocular , Adulto Jovem
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