共查询到20条相似文献，搜索用时 31 毫秒
1.
Michael J. Doughty 《Contact lens & anterior eye》2017,40(2):109-115
Purpose
To assess if polymegethism and pleomorphism were evident in corneal endothelium after medium-term rigid gas permeable (RGP) contact lens wear.Methods
In a cross-sectional observational study over 12 years, single images of the central region of the corneal endothelium of one eye of 46 subjects were taken with a non-contact specular microscope, along with a measure of central corneal thickness (CCT). The images were printed onto A3-sized paper and 100 cells/image measured by planimetry.Results
Subjects aged between 20 and 32 years, with an average cumulative RGP wear of 6.0 +/? 1.6 years (range 3–9 years) were assessed; 26 of the subjects were Caucasian and 20 were Asian. The mean CCT was 0.515 +/? 0.027 mm. The group cell area value was 401 +/? 42 sq micron to give an estimated endothelial cell density (ECD) of 2520 +/? 273 cells/sq mm. As compared to a historical database, most endothelia (37/46) showed some changes with the mean coefficient of variation on cell area (COV) being 36.7 +/? 8.0% and the percentage of 6-sided (HEX) being 51.8 +/? 8.8%. There were modest correlations between years of RGP wear and both COV (p = 0.009, r spearman = 0.424) and HEX (p = 0.025, r spearman = ?0.291), but not for ECD or CCT.Conclusions
Corneal endothelial polymegethism appears to be a commonplace consequence of RGP lens wear with the magnitude of the change being related to the cumulative duration of the lens wear. 相似文献2.
Purpose
To compare vision correction preferences, refractive error, and gender of non-presbyopes and presbyopes.Methods
Adults who wear spectacles or contact lenses completed a survey about refractive correction opinions and refractive error was measured.Results
Of the 304 subjects, 38.2% were presbyopic (≥40 years) and 59.2% were female. Spectacles were the primary vision correction for 78.0% of subjects. Compared to contact lens wearers, the proportion of presbyopes was higher (p = 0.006) in spectacle wearers. There was no difference in the proportion of presbyopes and non-presbyopes who have tried contact lenses (p = 0.2) or who would prefer to wear contact lenses (p = 0.2). In contact lens wearers, there was no difference in the proportion of presbyopes and non-presbyopes with a history of temporary discontinuation (p = 0.9). Within the contact lens wearing group, there was no refractive error difference between presbyopes and non-presbyopes (spherical equivalent p = 0.6; power vector J0 p = 0.5; power vector J45 p = 0.4; anisometropia p = 0.2). Overall, contact lens wearers were more likely to be female (p = 0.004). There was no difference in gender in presbyopic and non-presbyopic contact lens wearers (p = 0.5).Conclusions
Presbyopes and non-presbyopes have similar opinions about spectacles and contact lenses. Presbyopes of all refractive errors prefer contact lens correction when good vision and comfort can be achieved. Eye care providers should not assume that presbyopia, refractive error, or gender are factors that preclude a patient from being interested in contact lens wear. 相似文献3.
Aoife Lloyd-McKernan Luisa Simo Mannion Veronica O’Dwyer 《Contact lens & anterior eye》2017,40(5):301-310
Purpose
To examine the influence of previous soft contact lens (SCL) wear on corneal refractive surgery (CRS) outcomes when SCL wear is ceased for two weeks versus twenty-four hours, and also when compared to no wear, prior to CRS.Methods
A retrospective examination of CRS patient records was carried out for two groups of patients- who ceased SCL wear for two weeks (n = 45) and for twenty-four hours (n = 49) prior to CRS and compared to a non-contact lens (NCL) control group (n = 45 and n = 49, respectively). CRS outcomes (efficacy, predictability, visual acuity and refractive error) were compared pre-operatively and one and six months post-operatively.Results
One month post-operative results found unaided distance visual acuity (UDVA) was significantly better for LASEK/PRK patients who had ceased SCL wear for two weeks prior to CRS (?0.05 ± 0.09), compared with the NCL group (0.02 ± 0.09; p = 0.04). Furthermore, six month post-operative results found UDVA was significantly better for both LASIK and LASEK/PRK patients who had ceased SCL wear for two weeks prior to CRS, and for LASEK/PRK patients who had ceased SCL wear for twenty-four hours prior to CRS compared with the NCL group.Conclusions
Given the current setup and methods followed, it was concluded that previous SCL wear had no negative impact on visual outcomes following CRS compared with a NCL control group, regardless of previous SCL cessation time prior to CRS. 相似文献4.
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5.
Purpose
To report a case of lens discontinuation in a long term orthokeratology (OK) lens wearer and describe regression in refraction, corneal topography, and corneal thickness over 408 days after lens discontinuation. Furthermore, the outcome of subsequent LASIK treatment is also reported.Case report
A 41 year old Caucasian female who had been previously wearing OK lenses for 13 years discontinued lens wear in the left eye to consider refractive surgery in that eye. The greatest changes in subjective and objective refractions, corneal topography and thickness occurred during the first 28 days after lens discontinuation. Subjective refraction did not reach baseline values, but corneal topography parameters returned to pre-OK values after 408 days of no lens wear. The patient then received successful refractive surgery treatment in that eye, achieving uncorrected visual acuity of 0.00 LogMAR units, and residual refractive error within ±0.50 D of emmetropia.Conclusion
The period of lens discontinuation required for long term OK lens wearers before refractive surgery is likely to vary between individuals and the patient described in this case report required a significant period of lens discontinuation of at least one year before being considered suitable for refractive surgery. 相似文献6.
Purpose
This study aims to evaluate the settling of a scleral lens and if this process is influenced by the nature of the fluid layer.Methods
A prospective, non-randomized control study was performed using an 18 mm scleral lens. They were fitted with a central clearance of 400 um at insertion. One eye was randomly assigned to be fitted with a non-preserved gel solution of carboxymethylcellulose, while the other was inserted with non-preserved saline. Measurements of clearance in 3 locations were taken (OCT) at baseline, every 30 min up to 1h30 post insertion and every 2 h thereafter up to 6h00 of wear. A two-way repeated measure analysis of variance (liquids × times) was used to test central, nasal and temporal fluid thickness.Results
Following 6 h of wear, the 18 mm lens had a mean central settling of 70.0 ± 9.8 μm, 36.7 ± 9.8 μm of which occurred within the first 30 min of wear. There was no significant difference between lenses filled with non-preserved saline to those with non-preserved gel. However, a paired comparison concluded to a significant difference between mean nasal settling (41.4 μm) and temporal settling (20.4 μm).Conclusion
With respect to the lens studied, current results suggest that practitioners can evaluate the lens 30 min post insertion and can estimate the amount of fluid that will remain after lens stabilization by doubling the value obtained initially. The use of non-preserved saline or non-preserved more viscous solution to fill the lens does not influence its settling. 相似文献7.
Esteban Porcar Juan Carlos Montalt Enrique España-Gregori Cristina Peris-Martínez 《Contact lens & anterior eye》2017,40(3):190-194
Purpose
We describe a case of fitting a corneo-scleral contact lens with a multi-aspheric geometry design (MAGD CScL) on top of a daily silicone hydrogel lens (piggyback system) for keratoconus management.Methods
A 48-year-old man using soft toric contact lenses required an improvement in the unsatisfactory quality of his vision. He presented with bilateral asymmetric keratoconus with high myopia in the right eye (RE) and severe myopia in the left eye (LE). In addition, he had low vision in his LE because of a maculopathy. He was fitted with MAGD CScL to correct his irregular astigmatism. A diagnostic trial set was used in the fitting process and the patient was assessed according to a standardised fitting methodology. Visual acuity, corneal topography and contrast sensitivity were evaluated. The follow-up period was 1 year.Results
The best spectacle-corrected visual acuity was 0.5 logMAR for the RE with ?10 D/-5 D × 60° and 2 logMAR for the LE with ?20 D/-3 D × 105°. After fitting MAGD CScL, visual acuity improved significantly to 0.1 logMAR for the RE and 1.3 logMAR for the LE, as well as contrast sensitivity. The fitting parameters of the base curve, diameter, and power were 7.05 mm, 12.60 mm, ?18.50 D and 7.15 mm, 12.60 mm, ?19 D for the RE and LE, respectively. Optimal fitting characteristics were found in terms of lens position and lens movement. To increase the time of MAGD CScL wear, they piggybacked on daily silicone hydrogel lenses of low power (?0.5 D). The patient reported being comfortable with this piggyback system for approximately 15 h a day. After 1 year of using the piggyback system, visual quality and wearing time were maintained. In addition, no adverse ocular effects were found during this period.Conclusion
This case report shows that in this patient a MAGD CScL could be fitted successfully on a daily silicone hydrogel lens in a piggyback system for keratoconus management, providing good visual quality along with prolonged use times and without adverse effects on the cornea. 相似文献8.
Debarun Dutta Timothy Zhao Kai Bing Cheah Larke Holmlund Mark D.P. Willcox 《Contact lens & anterior eye》2017,40(3):175-183
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9.
Michael T.M. Wang Kalaivarny Ganesalingam Chee Seang Loh Trisha Alberquerque Suhaila Al-Kanani Stuti L. Misra Jennifer P. Craig 《Contact lens & anterior eye》2017,40(1):53-58
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10.
Purpose
To evaluate a novel fitting algorithm for estimation of alignment curve (AC) radius during orthokeratology lens trial.Methods
Fifty myopic children were recruited in this study. AC radii were estimated by both traditional method using flat K readings and eccentricity values and by a novel fitting algorithm, which was composed of 256 circle fittings using corneal elevation data from the corresponding AC region and a succedent toric fitting based on these calculated AC curvatures. Parameters of the final ordered lenses were determined by fluorescein analysis and corneal topography. The number of lens trials was recorded for each patient, and the consistencies of AC radius and astigmatism between the first trial lenses and the final ordered lenses were tested by Pearson correlations and Bland-Altman plots.Results
The numbers of trials for the novel algorithm and traditional method were 1.2 ± 0.4 times vs. 1.8 ± 0.7 times, respectively, and Mann-Whitney test showed significant difference (z = ?3.27, p = 0.001). AC radii of the first trial lenses estimated by the novel fitting algorithm were more close to that of the final ordered lenses, showing a R square value of 0.994 for the fitting algorithm and 0.927 for the traditional method, respectively. Similar results could also be noticed for astigmatism estimation.Conclusion
AC radius and astigmatism of ortho-k lens could be better estimated by two steps of fitting algorithm using corneal elevation data, which may shorten the time needed for ortho-k lens trial and achieve better lens fitting status. 相似文献11.
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12.
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13.
Aim
To analyze the demographics, risk factors, clinical and microbiological characteristics of cases of bilateral simultaneous infective keratitis.Methods
In this retrospective case series, patients with clinical evidence of bilateral simultaneous infective keratitis were identified from January 1, 2011 to August 31, 2016. Demographics, risk factors, clinical and microbiological characteristics, and treatment outcomes were analyzed.Results
Five patients (ten eyes) with bilateral simultaneous infective keratitis were identified. The mean age was 32.8 years (SD, ± 8.8; range, 24–44). All the patients were disposable soft contact lens wearers before presentation. The average size of the infiltrate was 4.76 mm2 (SD ± 9.0; range, 0.2–31.34). A total of 4 types of bacteria were isolated, with Pseudomonas aeruginosa being the most frequently isolated bacteria involving 5 eyes of four patients. Infection resolved with medical treatment in 9 eyes, 1 patient required therapeutic corneal transplantation for impending corneal perforation. The average time taken for infection to resolve was 6.7 days (SD ± 4.5; range, 2–16).Conclusions
In this case series, the most common risk factor of bilateral simultaneous microbial keratitis was use of soft disposable contact lens and the most commonly isolated bacteria was Pseudomonas aeruginosa. Bilateral simultaneous infective keratitis is uncommon and is a serious complication of contact lens use in immunocompetent adult patients. 相似文献14.
Corneo-scleral contact lenses in an uncommon case of keratoconus with high hyperopia and astigmatism
Esteban Porcar Juan Carlos Montalt Enrique España-Gregori Cristina Peris-Martínez 《Contact lens & anterior eye》2017,40(5):351-356
Purpose
To analyse the visual quality achieved by fitting corneo-scleral contact lenses (CScL) in an uncommon case of bilateral keratoconus, high hyperopia and astigmatism.Methods
A 45-year-old man presented for eye examination due to the unsatisfactory quality of his vision wearing soft toric contact lenses. He presented high hyperopia and astigmatism with bilateral keratoconus. He was fitted with CScL to correct his irregular astigmatism and ocular aberrations. A diagnostic trial set was used in the fitting process and he was assessed according to standardised fitting methodology. Visual acuity, corneal topography, biometry and ocular aberrations were evaluated. The follow-up period was 1 year.Results
The best spectacle-corrected visual acuity was 20/32 with +8.00/?4.50 × 30° for the right eye (RE) and 20/25 with +7.75/?2.25 × 120° for the left eye (LE). After CScL fitting, visual acuity was improved to 20/20 and 20/16 for the RE and LE, respectively. The patient wore these contact lenses an average of 13 h a day. The total high order aberrations decreased by approximately 79% in the RE (2.37–0.50 μm) and 47% in the LE (1.04–0.55 μm) after CScL fitting. Visual quality and wearing time were maintained after 1 year wearing CScL. In addition, no adverse ocular effects were found during this period.Conclusion
The present case report describes how the patient had CScL fitted successfully for management of keratoconus with high hyperopia and astigmatism. They provided optimal visual quality, along with prolonged use times and no adverse effects to the cornea. 相似文献15.
Saadettin Sel Jana Stange Delia Kaiser Laszlo Kiraly 《Contact lens & anterior eye》2017,40(5):318-322
Purpose
To evaluate the repeatability and comparability of biometry parameters between a Scheimpflug-based topography with axial length measurement (Pentacam AXL, Oculus, Wetzlar, Germany) and a swept-source optical biometry (IOLMaster 700, Carl Zeiss Meditec AG, Jena, Germany).Methods
A total of 50 eyes from 50 adult subjects had biometry measurements in one session three times using the Pentacam AXL and the IOLMaster 700. Keratometry, anterior chamber depth (ACD) and axial length (AL) values were obtained by both devices. Mean keratometry (Kmean) was calculated and the corneal spherocylinder was converted into power vectors (J0, J45). Repeatability was assessed based on intraclass correlation coefficient (ICC). Agreement was evaluated by linear regression analysis and Bland–Altman analysis by calculating the mean difference and 95% limits of agreement (LoA).Results
Assessment of intraoperator repeatability by means of ICC showed excellent reproducibility of measurements for both devices and all parameters examined ranging from 0.994 to 1.0. IOLMaster 700 exhibited significantly higher Kmean (p < 0.001) and AL (p < 0.001) values than the Pentacam AXL. Pentacam AXL showed significantly higher ACD (p < 0.001) measurements than IOLMaster 700. There was no statistically significant difference of J0 (p = 0.115) and J45 (p = 0.255) values between Pentacam AXL and IOLMaster 700.Conclusions
Both devices provide high reproducible values for all parameters investigated. J0 and J45 values are statistically and clinically interchangeable between Pentacam AXL and IOLMaster 700. All other parameters are statistically different. In clinical practice, the differences for ACD and AL are to small and the values can be used interchangeable. However, Kmean values are clinically and statistically different and cannot be used interchangeable between the two devices. 相似文献16.
Xiaolin Zhang Christine Marchetti Jessica Lee Yan Sun Sara Debanne Ying Jiang Jami Kern Mark Harrod Beth Ann Benetz Eric Pearlman Loretta Szczotka-Flynn 《Contact lens & anterior eye》2017,40(1):33-41
Purpose
To assess corneal epithelial microstructure via confocal microscopy and determine if cellular changes are associated with lens care solutions during daily wear of silicone hydrogel contact lenses.Methods
Corneal in vivo confocal microscopy with the Nidek ConfoScan4 was performed at baseline and after 5 months of lotrafilcon A daily contact lens wear. Enrolled participants were randomized to use either a polyhexamethylene biguanide (PHMB) preserved multipurpose care solution (MPS) or a peroxide based solution system. Lens and storage case bioburden were assessed with aerobic culture methods. Univariate and multivariable analyses were done to evaluate the association between solution use, or solution-related clinical covariates, and morphologic differences (hyper-reflectivity) in the superficial epithelial cells and epithelial basal cell density.Results
Data on 139 participants were available for analysis of superficial epithelial cells while data on 92 participants were available for epithelial basal cell density. Five months after randomization to the solution groups, 33% of participants had visible hyper-reflective cells. More participants using MPS had ≥1 hyper-reflective cells compared to peroxide users at 5 months (44% vs. 22%; p = 0.006). Similarly at 5 months, more participants with solution-induced corneal staining (SICS) had ≥1 hyper-reflective cells compared to non-SICS participants (57% vs. 29%; p = 0.010). The adjusted odds ratios (ORs) for risk of presenting with hyper-reflective cells in MPS users or SICS participants was 2.7 (95% CI; 1.27–5.65) and 3.4 (95% CI; 1.29–8.97), respectively. Basal cell density decreased by over 350 cells/mm2 over time (about 6%) in participants who had substantial bioburden on their lenses or in their storage case.Conclusion
The confocal microscope can detect epithelial cellular changes in vivo during contact lens wear. Hyper-reflective superficial epithelial cells are associated with a PHMB preserved solution and decreases in basal epithelial cell density may be associated with bacterial bioburden. 相似文献17.
Purpose
To investigate effect of topical anaesthetic (TA) during gas permeable (GP) contact lens (CL) fitting on subjective and objective measures of patient anxiety.Methods
47 subjects (mean ± sd age = 26.9 ± 4.9 years; soft CL wearers, 18, neophytes, 29). Each subject randomly assigned to Group A or B, and attended on two occasions, one week apart. First visit: subject received bilaterally either a single drop of TA (0.5% proxymetacaine) (Group A) or placebo (0.9% saline) (Group B) prior to GP CL application. No drops were instilled at second visit. Each visit mimicked a GP CL fitting. At each visit, patient anxiety was assessed either subjectively (visual analogue scale (VAS)) or objectively (skin conductance (SC)), as well as anterior ocular health.Results
Visit 1: GP CL trial produced small increases in hyperaemia and corneal staining, but no difference associated with TA use. Visit 2: increases in staining and hyperaemia were observed, but hyperaemic responses significantly less than at Visit 1, for both groups. Corneal staining also less, but not statistically significant. VAS scores indicated subjects who received TA during Visit 1 were significantly less anxious at Visit 2. Visit 2: comfort slightly reduced for subjects who received TA at Visit 1, and significantly increased for subjects who received placebo. Use of TA reduced anxiety during lens adaptation period compared with subjects receiving placebo.Conclusions
TA use during GP CL fitting has potential patient benefits: improved first-time GP CL wear comfort, reduced anxiety during adaptation, reduced anxiety prior to subsequent GP CL wear. 相似文献18.
Purpose
To develop a new and precise methodology to measure the scleral radius based on anterior eye surface.Methods
Eye Surface Profiler (ESP, Eaglet-Eye, Netherlands) was used to acquire the anterior eye surface of 23 emmetropic subjects aged 28.1 ± 6.6 years (mean ± standard deviation) ranging from 20 to 45. Scleral radius was obtained based on the approximation of the topographical scleral data to a sphere using least squares fitting and considering the axial length as a reference point. To better understand the role of scleral radius in ocular biometry, measurements of corneal radius, central corneal thickness, anterior chamber depth and white-to-white corneal diameter were acquired with IOLMaster 700 (Carl Zeiss Meditec AG, Jena, Germany).Results
The estimated scleral radius (11.2 ± 0.3 mm) was shown to be highly precise with a coefficient of variation of 0.4%. A statistically significant correlation between axial length and scleral radius (R2 = 0.957, p < 0.001) was observed. Moreover, corneal radius (R2 = 0.420, p < 0.001), anterior chamber depth (R2 = 0.141, p = 0.039) and white-to-white corneal diameter (R2 = 0.146, p = 0.036) have also shown statistically significant correlations with the scleral radius. Lastly, no correlation was observed comparing scleral radius to the central corneal thickness (R2 = 0.047, p = 0.161).Conclusions
Three-dimensional topography of anterior eye acquired with Eye Surface Profiler together with a given estimate of the axial length, can be used to calculate the scleral radius with high precision. 相似文献19.
Varsha M. Rathi Preeji S. Mandathara Srikanth Dumpati Virender S. Sangwan 《Contact lens & anterior eye》2017,40(3):157-161
Purpose
To assess the change in vault during scleral lens fitting with anterior segment optical coherence tomography (AS-OCT).Methods
This study comprised of patients who had AS-OCT performed after 1 h and 4 h of scleral lens wear (PROSE, prosthetic replacement of the ocular surface ecosystem, Boston Foundation for Sight, Needham Heights, MA, USA). Vault was measured on AS-OCT as the distance between the front surface of the cornea in the center and the back surface of the scleral lens.Results
Fifty eyes of 41 patients were analyzed. The main indications for scleral lens trial were ectasia (keratoconus, post surgery) (n = 20 eyes) and ocular surface disease (OSD – Stevens – Johnson syndrome, dry eyes and limbal stem cell deficiency) (n = 30 eyes). Mean age of the patients was 31.4 years. Twenty were males. The diameter of the scleral lens ranged from 16 mm to 18.5 mm. Vault measurements reduced in 45/50 eyes (90%), remained same (n = 2) or increased (n = 3). Overall mean vault decreased from 680 ± 421 μm at 1 h to 589 ± 355 μm (p = <0.001) at 4 h of lens wear. Mean vault in ectasia was 759 ± 574 μm and 634 ± 455 μm (p = 0.02) at 1 h and 4 h of lens wear respectively. In OSD group, mean vault was 626 ± 276 μm and 558 ± 273 μm (p < 0.01) at 1 h and 4 h of lens wear respectively. Average reduction in the vault was 125 μm in ectasia and 68 μm in OSD group.Conclusion
Vault reduced significantly after 4 h of lens wear during scleral lens trial indicating that the final assessment of the scleral lens may be done after 4 h of lens wear. 相似文献20.
Wei Wang Miao He Hong He Chi Zhang He Jin Xingwu Zhong 《Contact lens & anterior eye》2017,40(2):97-103