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Purpose: To review the microbiologic profile, clinical course, treatment, and outcome of patients with cosmetic contact lens (CL)-associated ulcerative keratitis. Materials and Methods: Observational noncomparative case series selected from an ongoing prospective series. Forty-six subjects examined at a corneal specialty practice in Abha, southern Saudi Arabia between April 2012 and June 2013, who presented with corneal stromal infiltrate on slit-lamp examination, were included in the study. Results: All patients were emmetropic, and lenses were worn solely for cosmetic purposes. Nine (19.5%) of 46 CL-wearing patients presented with laboratory-proven infectious keratitis. Pseudomonas was the most common organism (6/9; 66.6%). Staphylococcus species were the second most common, occurring in two (22.2%) of the nine cases. Streptococcus viridans in one case (11%). Laboratory-based medical therapy led to the healing of ulcers in all cases. Thirty-seven (80.4%) patients had sterile infiltrates. Conclusions: Over-the-counter use of cosmetic lenses is rapidly increasing. The easy availability of these lenses is resulting in severe sight-threatening complications in some young emmetropic individuals. Prompt treatment of microbial keratitis is important to prevent vision loss. [ABSTRACT FROM AUTHOR]

Background and objective: We describe a miniaturized lightweight high-refractive-index panretinal contact lens for diagnostic and therapeutic visualization of the peripheral retina. Instrument design: The miniaturized high-resolution wide-field contact lens includes three optical elements in a light (15 g) and miniaturized (16 mm footplate, 24 mm external aperture, and 21 mm vertical height) casing contributing to a total dioptric power of +171 diopters. This lens provides up to 165° visualization of the retina for diagnostic and therapeutic applications while allowing easier placement due to its miniaturization. Conclusion: This new lens (50% lighter and 89% smaller) improves upon earlier contact lenses for visualization of the peripheral retina. [ABSTRACT FROM AUTHOR]

Purpose To quantify the optical quality of various daily disposable contact lenses in vivo and to ascertain its variation in terms of wearing time by means of objective non-invasive determination of wavefront patterns. Methods The crx1 adaptive-optics system was used to measure the wavefront aberrations in 15 myopic eyes before and at 2-h intervals after contact lens fitting, over a 12-h wearing period. Seven types of contact lenses having different material, water content and lens design were evaluated in this study: Dailies Total1, Dailies Aqua Comfort Plus, Proclear 1 Day, 1-Day Acuvue Tru Eye, 1-Day Acuvue moist, Sof Lens daily disposable and Clariti 1-Day. The aberration data were analysed by fitting Zernike polynomials up to the 5th-order for 3 and 5-mm pupils. The optical quality under each condition and at each point in time was described by means of the Root-Mean-Square ( RMS) value of wavefront aberration, Modulation Transfer Function ( MTF), Point Spread Function and cut-off spatial frequency. Results A RMS increase was observed after contact lens fitting as well as over time, both for a 3-mm and a 5-mm pupil. Each type of lens induced a different amount of wavefront aberrations, which vary over time also in a different manner. Dailies Total1 showed the lowest RMS values both at baseline and at the end of the day. In addition, Dailies Total1 provided the best MTF out of all the contact lenses that were assessed. These observations were reflected in higher cut-off spatial frequencies and visual resolution both at baseline and after 12 h of wearing time. Conclusions Aberrometry makes it possible to analyse accurately and in vivo the optical quality of contact lenses and to assess how lenses having different characteristics - such as material or water content - behave for different wearing times. These variations across contact lenses may result in differences in visual performance. [ABSTRACT FROM AUTHOR]

Background: Acanthamoeba keratitis (AK) is ever more frequently reported in industrialized countries. The loss of the corneal surface integrity consequent to secondary microtrauma produced by the use of contact lens (CL) favors the penetration of the parasite into the corneal tissue. Objectives: A scientific review was performed to investigate the association of CL wear as an Acanthamoeba keratitis (AK) risk factor. Methods: A computerized screening of 7834 Medline articles (4623 from PubMed; 3211 from Scopus) used a strict selection criteria of case-control studies involving CL wear and/or trauma. Results: The search yielded five case-control studies published from 1995 to 2012. All studies included showed a statistically significant positive association between AK and CL use, with a combined odds ratio (OR) of 10.21 (95%, confidence intervals [CI]; 3.57-27.64). Statistical analysis: All studies included showed a statistically significant positive association between AK and CL use, though with differing OR values. Conclusion: Though rare, AK should be held in higher consideration when ophthalmologists are faced with CL users exhibiting simplex-like lesions associated with circular stromal infiltrates and disproportionate ocular pain in respect to the objective clinical picture. [ABSTRACT FROM AUTHOR]

Background: Normal vision is essential to interact with widespread digital technologies. Higher order aberrations (HOA) are one of the important causes of image degradation in patients suffering from keratoconus, pterygium, or irregular astigmatism. These aberrations cannot be corrected by common ways of refractive errors correction like spectacles. Besides, other methods of HOA correction (e.g. customized contact lenses) are not easily accessible in many regions and photo-refractive surgeries like laser-assisted in situ keratomileusis (LASIK) are expensive. A novel method to correct HOA is pre-compensation of images displayed on computer monitors to provide unaberrated images. We used total variation (TV) deconvolution to pre-compensate images and compared the results with previous methods based on Wiener deconvolution. Methods: MATLAB was used for simulations. Each HOA was reconstructed using single-index scheme for Zernike coefficients. Pupil diameter was assumed to be four millimeters. Root-mean-square error of simulated aberrations was greater than 0.35 micrometers. Point spread functions corresponding to each HOA were created and TV deconvolution was used to pre-compensate the images. Findings: Strehl ratio of TV pre-compensation is very close to the results of Wiener pre-compensation method. Besides, execution time for TV Pre-compensation algorithm is about 20% faster than Wiener. Conclusion: Simulations ascertain that TV based pre-compensation method is a fast and efficient way to pre-compensate the images, and it could improve the patient's perceived retinal image quality. One more advantage of using TV algorithm is that we could enhance the results just by altering one parameter. [ABSTRACT FROM AUTHOR]

Citation information: Jinabhai A, Charman WN, O'Donnell C & Radhakrishnan H. Optical quality for keratoconic eyes with conventional RGP lens and simulated, customised contact lens corrections: a comparison. Ophthalmic Physiol Opt 2012, 32, 200-212. doi: 10.1111/j.1475-1313.2012.00904.x Abstract Purpose: To compare monochromatic aberrations of keratoconic eyes when uncorrected, corrected with spherically-powered RGP (rigid gas-permeable) contact lenses and corrected using simulations of customised soft contact lenses for different magnitudes of rotation (up to 15°) and translation (up to 1 mm) from their ideal position. Methods: The ocular aberrations of examples of mild, moderate and severe keratoconic eyes were measured when uncorrected and when wearing their habitual RGP lenses. Residual aberrations and point-spread functions of each eye were simulated using an ideal, customised soft contact lens (designed to neutralise higher-order aberrations, HOA) were calculated as a function of the angle of rotation of the lens from its ideal orientation, and its horizontal and vertical translation. Results: In agreement with the results of other authors, the RGP lenses markedly reduced both lower-order aberrations and HOA for all three patients. When compared with the RGP lens corrections, the customised lens simulations only provided optical improvements if their movements were constrained within limits which appear to be difficult to achieve with current technologies. Conclusions: At the present time, customised contact lens corrections appear likely to offer, at best, only minor optical improvements over RGP lenses for patients with keratoconus. If made in soft materials, however, these lenses may be preferred by patients in term of comfort. [ABSTRACT FROM AUTHOR]

Purpose: The aim was to determine the cytotoxic effects of three multipurpose solutions (MPS) on human corneal epithelial cells (HCEC) and to assess the metabolic rates of recovering cells at different levels of cell membrane damage. Method: The effects of one to 15 minutes exposure to multipurpose solutions containing polyquaternium-1 (MPS-A), polyaminopropyl biguanide (MPS-B) and polyhexanide (MPS-C) on HCEC were determined. Recovery rates at different levels of cell membrane damage were assessed after re-culture for two hours at 37°C. Cell viability and membrane integrity were assessed using Annexin V-FITC/7-AAD staining and flow cytometry. Effects of concentrations of 10 to 40 per cent multipurpose solutions on the metabolic rate of recovering HCEC were assessed using a Vybrant MTT cell proliferation assay kit. Results: The highest percentage of late necrotic cells resulted after exposure to MPS-A compared with other solutions and the control (p < 0.001). The percentages of early necrotic cells after 10 and 15 minutes of soaking in MPS-B were significantly higher than the control and other multipurpose solutions (p < 0.001). Although MPS-C exposure also resulted in statistically significant higher percentages of early necrotic cells than the control (p < 0.005), these differences were small. No recovery was noted when HCEC treated with multipurpose solutions were re-cultured, with numbers of dead cells in MPS-B-treated cultures increasing fourfold. The MTT assay showed significant dose-response decreases of 500 nm absorbance for all MPS-treated cells. In 40 per cent MPS-A-treated HCEC, lack of activity indicated the cells were non-viable. Conclusions: Multipurpose solutions induced varying levels of irreversible tissue sensitivity reactions, with MPS-A showing the greatest effects. The solutions damaged cell integrity and reduced metabolic rates suggesting delayed healing ability. The formulations of multipurpose solutions need to balance antimicrobial effectiveness with low cytotoxicity, which might not be currently possible to achieve. In light of our results, we suggest that contact lens wearers should be advised to rinse the soaked lenses with saline before lens insertion. [ABSTRACT FROM AUTHOR]

Purpose: The aim was to evaluate the disinfection properties of six multi-purpose contact lens disinfection solutions (MPDS) available in Iran against Fusarium solani and Candida albicans, based on the International Organization for Standardization (ISO) 14729 guidelines. Methods: Three lots each of six multi-purpose solutions, namely, Renu MultiPlus, Solo Care Aqua, All-Clean soft, Contact All In One Advanced, Hippia, Ginza Multi-Purpose Solution and 0.9% normal saline solution were inoculated with standard strains of Fusarium solani (ATCC 36031) and Candida albicans (ATCC 10231). Surviving fungi were determined by counting colony-forming units on recovery plates at specified times. The mean log reduction in fungal numbers at the manufacturer's minimum recommended disinfection time was determined and compared with the criteria for stand-alone disinfection products for each MPDS against each fungal strain. Results: Renu MultiPlus, Contact All In One Advanced and All-Clean Soft were effective in achieving the mean 1.0 log reduction in fungal numbers, based on ISO 14729 stand-alone primary acceptance criteria. Solo Care Aqua failed to achieve the ISO 14729 stand-alone primary acceptance criteria for Candida albicans. The other solutions were not effective against test microorganisms after the specified times. Conclusions: There were differences in the rates of disinfection efficacy. Generally, Renu MultiPlus, Contact All In One Advanced and All-Clean Soft exceeded the primary acceptance criteria of the ISO 14729 guidelines for stand-alone contact lens solutions. [ABSTRACT FROM AUTHOR]

Background: Contact lens-related infections are often associated with inadequate contact lens hygiene, and therefore, contact lens care products should be able to sufficiently minimise the amount of pathogens that are responsible for these infections. In 2001, the EN ISO 14729 was introduced to ensure adequate disinfection efficacy of contact lens care solutions, but this norm has recently been criticised. Methods: In this study, six frequently used contact lens care solutions were retested according to the Stand Alone Test of the EN ISO 14729 (2001). The Stand Alone Test is a quantitative suspension test. In addition, the products were tested in a modified setting adding an organic load. The load was a mixture of human blood serum, lysozyme, and mucine, which resembles tear fluid. Results: The criteria of the Stand Alone Test recommended in EN ISO 14729 were only met by Aosept Plus. This 3% hydrogen-peroxide-based contact lens care solution attained a reduction factor of > 5 log units for bacteria and > 4 for fungi in all cases. Two further contact lens care solutions, Blue Vision and Optifree Replenish, met the criteria of a reduction factor of > 3 log units for bacteria and > 1 log unit for fungi, but only in the presence of artificial tear fluid. The three remaining products did not exhibit adequate disinfecting efficacy, at least against one of the tested microorganisms. Conclusions: Through the observation that the artificial tear fluid used in this study influences the disinfecting efficacy of contact lens care solutions, especially that of multi-purpose solutions, in a different way than does albumin, mucine, or even the organic load suggested in EN ISO 14729, it becomes obvious that the test conditions in the EN ISO 14729 should be revised in order to create more realistic conditions, e.g., by using a more realistic artificial tear fluid. Furthermore, we suggest adapting the EN ISO 14729 to the European test hierarchy for chemical disinfectants and antiseptics, which consists of three test phases and also requests meeting stricter criteria in order to pass the test. Unless the test conditions guarantee a sufficient reduction of potential pathogens, the risk of contact lens-related microbial keratitis and other infections will remain for the users. [ABSTRACT FROM AUTHOR]

Purpose: We evaluated the usefulness of commercially available materials for protecting the cornea from drying during vitrectomy with a wide-angle viewing system. Methods: Three vitreoretinal surgeons evaluated fundus visibility during vitrectomy on the images of five study materials used on the cornea: balanced saline solution, a viscoelastic agent, a vitrectomy contact lens, a rigid gas permeable (RGP) contact lens, and a soft contact lens. Fundus visibility was graded using the following scale: grade 1, unclear; grade 2, slightly unclear; grade 3, clear; and grade 4, very clear. Results: Respective scores for each material used during core vitrectomy and membrane removal were: balanced saline solution, 3.3/3.3; viscoelastic agent, 3.8/3.3; vitrectomy contact lens, 3.3/4.0; RGP contact lens, 4.0/3.9; soft contact lens, 1.1/not applicable. Conclusion: The RGP contact lens provided visibility similar to or clearer than that obtained with other methods. Because of its ease of use and lower cost, use of the RGP contact lens is ideal during vitrectomy performed with a wide-angle viewing system. [ABSTRACT FROM AUTHOR]

Purpose: To assess the use of multipurpose lens care products via an online survey conducted among soft contact lens (SCL) wearers in Japan. Methods: The subjects were 1000 men and women aged 15--44 years who reported that they cleaned their SCL by using multipurpose solution at least twice a week. Via the internet, they were asked questions about SCL care, the use of a rubbing step when cleaning SCL, cleaning and replacing lens cases, and recommended SCL care methods. Results: Of the 1000 SCL wearers enrolled, 94.3% performed lens care every day lenses were worn, 64.2% reported rubbing the lenses every time, 57.9% rubbed the lenses for at least 10 seconds per side, and 64.7% reported they rubbed the lenses on both sides. Further, 61.2% reported that they had been given an explanation of SCL cleaning at an eye clinic or contact lens store. Only 49.8% of subjects reported that they cleaned the lens case every time and 61.7% replaced the case within 3 months. Only 19.5% had been given an explanation about lens case care. Half of the subjects reported they had been given no recommendation to use specific SCL care products or could not remember whether or not they had. The most common reason for the recommendation was good compatibility with their type of lens. Conclusion: More education is needed in Japan regarding methods of SCL care to ensure correct lens cleaning with inclusion of a rubbing step, as well as sufficient cleaning and replacement of the lens case. Of particular interest is the finding that many subjects were not given an explanation about proper SCL care and lens case cleaning and replacement at the time of lens purchase or prescription. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to assess whether differences in central corneal dendritic immune cell densities associated with combinations of soft contact lenses and lens care solutions could be detected by in vivo confocal microscopy. Methods: Participants were adults naïve to contact lens wear (n = 10) or who wore soft contact lenses habitually on a daily-wear schedule (n = 38) or on a study-assigned schedule for 30 days with daily disposable silicone hydrogel lenses (n = 15). Central corneas were scanned using an in vivo confocal microscope. Cell densities were compared among groups by demographic parameters, lens materials, and lens care solutions (polyhexamethylene biguanide [PHMB], polyquaternium-1 and myristamidopropyl dimethylamine [PQ/MAPD], peroxide, or blister pack solution [for daily disposable lenses]). Results: Among lens wearers, no associations were observed between immune cell densities and age, gender, or years of lens-wearing experience. Mean cell density was significantly lower (P < 0.01) in nonwearers (29 ± 23 cells/mm2, n = 10) than in lens wearers (64 ± 71 cells/mm2, n = 53). Mean cell density was lower (P = 0.21) with traditional polymer lenses (47 ± 44 cells/mm2, n = 12) than with silicone hydrogel lenses (69 ± 77 cells/mm2, n = 41). Lowest to highest mean density of immune cells among lens wearers was as follows: PQ/MAPD solution (49 ± 28 cells/mm2), blister pack solution (63 ± 81 cells/mm2), PHMB solution (66 ± 44 cells/mm2), and peroxide solution (85 ± 112 cells/mm2). Conclusion: In this pilot study, in vivo confocal microscopy was useful for detecting an elevated immune response associated with soft contact lenses, and for identifying lens-related and solution-related immune responses that merit further research. [ABSTRACT FROM AUTHOR]

Purpose: To report a case of aniridia in a pseudophakic patient following blunt trauma to the eye. Case report: The traumatized eye had cataract surgery through a 3.0 mm clear corneal incision 6 years prior to the incident. While there have been previous cases of traumatic aniridia in pseudophakic eyes, previous reports have all occurred closer to the time of the cataract surgery. We believe that the most likely mechanism of loss of iris tissue is through wound dehiscence, which would suggest the relative instability of clear corneal incisions several years postoperatively. The patient's visual acuity returned to 20/20 4 weeks post-trauma, with symptoms of glare which were managed by the use of a colored contact lens. Conclusion: The possibility of wound dehiscence should be recognized as an important clinical entity in the immediate postoperative period, but also several years following cataract surgery. [ABSTRACT FROM AUTHOR]

Background: The monitoring and assessment of the upper tarsal conjunctiva can be enhanced by the use of a grading scale. The aim of this study was to categorise the appearance of normal tarsal conjunctiva among young adults in Malaysia using the Institute for Eye Research grading scale and to investigate inter- and intra-observer agreement. Methods: The appearance of the upper tarsal conjunctiva of 416 non-contact lens wearing subjects aged between 19 to 24 years was assessed by two separate observers for roughness and redness in three separate zones using the Institute for Eye Research grading scale. The average grade for each zone and overall grade for roughness and redness were calculated. Inter- and intra-observer agreements were analysed. Results: Subjects were categorised for ethnicity and the roughness and redness were calculated. No significant differences were found between Malay and Chinese eyes (p > 0.05). The average grades for the upper tarsal conjunctiva redness and roughness were 0.90 ± 0.25 and 0.86 ± 0.43, respectively. Significantly higher roughness scores were found in zone 1 compared to the other two zones (p = 0.03). Significant association was also found between tarsal conjunctiva redness and roughness (Spearman ρ= 0.45, p < 0.001). Correlation between redness and roughness with age (p = 0.48, p = 0.65) and gender (p = 0.30, p = 0.79) were not significant. Only 2.2 per cent of subjects had scores higher than 2.0 for roughness or redness. Inter- and intra-observer analysis showed good agreement between two observers during the study. Conclusion: The roughness and redness of normal tarsal conjunctiva among young adults in Malaysia were found to be less than two units. Results of this study might be beneficial in clinical trials using contact lenses where changes in the tarsal conjunctiva are commonly used as an outcome measure. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the present study was to compare central and peripheral corneal thickness measurements in corneas with and without contact lens (CL)-induced corneal swelling, in order to establish the constancy of the Orbscan acoustic factor (AF) for reliability in detection of CL-induced corneal swelling. Methods: Corneal thickness was measured in five corneal locations (central, superior, inferior, nasal and temporal) using both ultrasonic and Orbscan pachymetry before and after one week of high Dk (lotrafilcon A) and low Dk (etafilcon A) contact lens continuous wear (CW). Lenses were randomly fitted for CW in the right and left eyes of 20 healthy subjects to induce various amounts of corneal swelling. Results: Etafilcon A contact lenses induced greater corneal swelling than the lotrafilcon A contact lenses (p < 0.05, paired Student t-test). Equal corneal swelling percentages (with and without the application of the acoustic factor) were determined from Orbscan measurements. Application of the 0.92 AF did not permit adjustment to all corneal locations. The correlations between Orbscan with and without the 0.92 AF and ultrasonic pachymetry were higher for central pachymetry (r² > 0.88; p < 0.01) and lower for peripheral pachymetry (r² < 0.58; p < 0.01) with similar trends in corneas with and without CL-induced swelling. Conclusions: The acoustic factor proposed by the manufacturer to obtain corneal thickness with the Orbscan compared with those from ultrasonic pachymetry was not valid for all corneal topographic positions. The AF is unnecessary when determining CL-induced corneal swelling. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of toric and soft spherical contact lenses on the visual performance and wavefront aberrations in cases of low astigmatism. Material and Method: Twenty-four eyes of 14 contact lens users with cylindirical refractive error of -1.25 diopters or less were included in this prospective study. The subjects wore spherical (lotrafilcon B) and toric (galyfilcon A) lenses for eight hours with a one-week interval. The best-corrected visual acuity and contrast sensitivity were measured before and after 8 hours of contact lens wear. Corneal topography and wavefront analysis were also performed. Zernike coefficients were used to calculate the aberrations at a 6-mm pupil diameter. Total and higher-order root mean square (RMS) values as well as spherical and coma aberrations were measured. Result: The mean spherical refractive error of the cases was -2.52±1.25 (range: from -0.50 to -6.0) D. The mean best- corrected visual acuity was significantly higher with both types of contact lenses than with glasses (p=0.017), however, no statistical difference was observed between the two types of contact lenses (p=0.470). The mean high-frequency contrast sensitivity value was lower with toric lenses (p=0.038). The mean higher-order RMS value was higher with both types of contact lenses (p=0.021), but with no difference between them (p>0.05). The mean spherical aberration value did not differ among glasses, toric or soft spherical contact lenses (p>0.05). The mean coma aberrations were high with both types of contact lenses (p=0.041); no difference was observed between the two lens types (p>0.05). Discussion: In this study, it was demonstrated that in cases of low astigmatism, soft spherical and toric contact lenses increase visual acuity, total higher-order aberrations, and coma aberrations, but decrease high-frequency contrast sensitivity. There was no difference between the two types of contact lenses. [ABSTRACT FROM AUTHOR]

In this article, the materials used for glass (mineral) and plastic (organic) spectacle lenses and the properties of monofocal, bifocal, trifocal and multifocal spectacle lenses are investigated. On the other hand, the new generation personalized lenses, which were produced by freeform technology and customized high resolution (HD) wavefront-guided spectacle lenses and ongoing glass research studies are also discussed. [ABSTRACT FROM AUTHOR]

Background: It is generally believed that the clinical performance of the original Czechoslovakian hydrogel contact lenses was poor but historical reviews provide very little explanation regarding their failings. There is a lack of information in the literature about their dimensions and, in particular, thickness, which is essential for the calculation of oxygen transmissibility. Until now no measurements on Czechoslovakian lenses have been reported. Methods: A literature search on Czechoslovakian lenses was made that spanned the first decade of their use and included peer-reviewed journals, non-refereed publications and a number of archived documents. In addition, the water content and dimensions of five Geltakt and four Spofa lenses were measured. Results: Lens packaging, lens lifetime, hygienic care, visual acuity, nominal lens dimensions, flexure, failure to correct astigmatism, corneal oedema, oxygen transmissibility, complications and wearing time are reviewed. Measurements on Czechoslovakian lenses indicate that the total diameter was similar to that of the cornea, the back optic zone radius was steep and the centre thickness was large. Conclusion: Problems associated with the Czechoslovakian lenses included packaging and an initial failure to require daily disinfection. Few complications of lens wear were reported, probably due to the comparatively small number of patients fitted and the limited wearing time that they achieved. Delayed disclosure of lens dimensions handicapped the development of a fitting technique. An acceptable visual acuity was attained in selected cases, while reduced acuity may sometimes have been due to uncorrected astigmatism or to poor lens quality. The most serious disadvantage was the very low oxygen transmissibility that could result in marked corneal oedema. [ABSTRACT FROM AUTHOR]

The visual outcomes for infants 18 months or younger with cataracts have improved dramatically over the past couple of decades. Earlier detection of infantile cataract and prompt surgical removal—with subsequent visual rehabilitation with contact lenses—mean that these patients now have a much better visual prognosis. Advances in contact lens technology have led to a significantly higher success rate with contact lenses and this has been a major factor in improving the visual outcomes for aphakic infants. This review outlines the contact lens management of infantile cataract, including a detailed analysis of the various contact lens options available and a discussion regarding the important factors that can cause issues with contact lens wear and affect the overall visual rehabilitation of the infant. [ABSTRACT FROM AUTHOR]

Purpose: Recent outbreaks of microbial keratitis have increased concerns about the efficacy of multipurpose solutions (MPS) against ‘real-world’ organisms. This study determined, in accordance with FDA/ISO standard methods, the effects of five MPS against clinical isolates and type strains of bacteria, and isolates of fungi from subjects’ ocular structures; and of three MPS against environmental fungal isolates. Method: MPS were challenged with bacteria (type strains (ATCC) and clinical isolates of bacterial pathogens obtained from a district hospital laboratory) and with fungal isolates from both the periocular and conjunctival structures and from environmental air. Results: All MPS demonstrated at least a 3-log reduction of challenged cell viability of all bacterial species tested, with the exception of MPS D against a canine infection Staphylococcus aureus isolate. Whilst all MPS tested were able to effect a 1.0-log reduction of viability of Fusarium solani (ATCC 36031), only two MPS had 90% viability reduction against all fungi of human origin and only one of these against all environmental fungal isolates. Effectiveness of these two solutions against fungal isolates compared to the remaining three MPS was found to be statistically significant ( p = 0.003). Conclusions: All MPS demonstrated a 99.9% viability reduction against a wide range of bacteria including major ocular pathogens not currently included in the FDA panel. The inability of three MPS to achieve a 90% reduction against fungal isolates is of concern as there has been a recent upsurge in reports of fungal keratitis. We would recommend extension of the current FDA testing panel for MPS to include more fungal isolates. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effects of a customised manipulation of spherical aberration (SA) on the high and low contrast visual acuities and contrast sensitivity of young adult myopes. Methods: A placebo-controlled double masked trial of customised spherical aberration controlling soft contact lenses was undertaken in myopes aged 15–23. Participants wore customised soft contact lenses with either (i) zero spherical aberration or (ii) negative spherical aberration that resulted in a net SA (eye plus lens) of −0.1 micron. High and low contrast log MAR visual acuities and Pelli Robson contrast sensitivity were assessed in 196 eyes of 98 subjects after a period of 12 months wearing the lenses. Results: Both high and low contrast acuities were significantly better in the group wearing the contact lenses with negative spherical aberration (high contrast log MAR, p = 0.043; low contrast log MAR, p = 0.043) which was not due to differences in residual astigmatism or pupil size between the two groups. Pelli Robson contrast sensitivity was not significantly different in the two groups. Conclusions: Manipulation of spherical aberration, taking account of the participants’ baseline level of aberration, can cause statistically significant improvements in high and low contrast distance visual acuity although these improvements are too small in magnitude to be of clinical significance. [ABSTRACT FROM AUTHOR]

Purpose: A population based, cross-sectional telephone survey was conducted to estimate the total penetrance of contact lens wear in Australia. Methods: A total of 42,749 households around Australia were randomly selected from the national electronic telephone directory based on postcode distribution. Before contact was attempted, letters of introduction were sent. The number of individuals and contact lens wearers in each household was ascertained and lens wearers were interviewed to determine details of lens type and mode of wear using a structured questionnaire. Results: Of households contacted, 59.2% (19,171/32,405) agreed to participate. Response rates were only marginally higher amongst households that first received a letter of introduction. In these households, 35,914 individuals were identified, of which, 1,798 were contact lens wearers. The penetrance of contact lens wear during the study period was 5.01% (95% CI: 4.78-5.24). Soft hydrogel lenses had the largest penetrance in the community, (66.7% of all wearers), however, their market share decreased significantly over the study period with increased uptake of newly introduced lens types. Conclusions: The penetrance of contact lens wear concurs with market estimates and equates to approximately 680,000 contact lens wearers aged between 15 and 64 years in Australia. The low response rate obtained in this study highlights the difficulty in contemporary use of telephone survey methodology. [ABSTRACT FROM AUTHOR]

In this paper, novel procedures were developed using a thin (0.17 mm) tactile piezoresistive pressure sensor mounted on a rigid contact lens to measure upper eyelid pressure. A hydrostatic calibration system was constructed, and the influence of conditioning (prestressing), drift (continued increasing response with a static load), and temperature variations on the response of the sensor were examined. To optimally position the sensor-contact lens combination under the upper eyelid margin, an in vivo measurement apparatus was constructed. Calibration gave a linear relationship between raw sensor output and actual pressure units for loads between 1 and 10 mmHg (R² = 0.96). Conditioning the sensor prior to use regulated the measurement response, and sensor output stabilized about 10 s after loading. While sensor output drifts slightly over several hours, it was not significant beyond the measurement time of 1 min used for eyelid pressure. The error associated with calibrating at room temperature but measuring at ocular surface temperature led to a very small overestimation of pressure. Eyelid pressure readings were observed when the upper eyelid was placed on the sensor, and removed during a recording. When the eyelid pressure was increased by pulling the lids tighter against the eye, the readings from the sensor significantly increased. [ABSTRACT FROM AUTHOR]

Purpose: In a double-masked randomized controlled crossover study we investigated both the retinal responses to straylight, and the effects of lens cleaners on straylight values, in two different RGP contact lens materials. Methods: Thirty patients (20–59 years) wearing RGP lenses were refitted with new lenses made of Boston XO material in one eye and made of Comfort O2 (ONSI-56) material in the other eye. Reported wetting angles for the Boston XO material (103°) and for the ONSI-56 material (7.2°) were obtained by sessile drop measurements. After refitting, the study comprised three 5-week trial periods. In Period 1 half of the participants (Group A) wore Boston XO lenses in their right eye and Comfort O2 (ONSI-56) lenses in their left eye, and the other half (Group B) vice versa. In Period 2 Group A wore Comfort O2 (ONSI-56) lenses in their right eye and Boston XO lenses in their left, and Group B vice versa. All participants used Miraflow cleaner during periods 1 and 2. In Period 3, during which all participants used Boston cleaner, Group A wore Boston XO lenses in their right eye and Comfort O2 (ONSI-56) lenses in their left eye and Group B vice versa. Straylight data (log S) were obtained with and without contact lenses using the Oculus C-Quant straylight meter in all three periods. Central corneal thickness (CCT) was measured in the second and third periods. Results: When not wearing lenses ( n = 60 eyes) at the end of the second 5 week trial period straylight was measured twice with averages of 1.07 log S, and the corrected CCT measurements averaged 546 μm. Straylight values with Comfort O2 (ONSI-56) reached 1.15 log S at the end of both the second ( n = 25 eyes) and third periods ( n = 23 eyes). Straylight values with Boston XO were 1.17 log S ( n = 26 eyes) at the end of the second period, and 1.16 log S ( n = 25 eyes) at the end of the third period. Conclusions: Existing RGP lens wearers refitted with new lenses with different contact angles, made of Boston XO and Comfort O2 (ONSI-56) showed, over three 5 week periods, relatively small increases in straylight, which were functionally comparable, irrespective of the type of lens material or lens cleaner used. At every visit, straylight values and CCTs returned to baseline levels after RGP lens removal, confirming that the straylight fluctuations were mainly due to scattering from the RGP lenses; or tear film interaction; or a combination of both. [ABSTRACT FROM AUTHOR]

Purpose: This study investigates how well the recently introduced Ocular Comfort Index (OCI) and the more established McMonnies Dry Eye Index are able to detect contact lens induced dry eye (CLIDE). Methods: Seventy volunteer contact lens wearers (mean age = 28.7 ± 8.0; 52 female, 18 male) were grouped as CLIDE positive or CLIDE negative depending on three sets of criteria: Method I: objective (tear meniscus height, lid parallel conjunctival folds, phenol red thread test and tear break-up time); Method II: objective and/or subjective [contact lens dry eye questionnaire (CLDEQ)] (i.e. being positive by Method I and/or Method III); Method III: subjective (CLDEQ). Symptoms were measured using the McMonnies Dry Eye Index and the OCI. Discrimination was analysed by the receiver operating characteristic (ROC) curves; positive predictive values (PPV) and cut-off values were calculated. Results: ROC results for Methods I and II were statistically significant only for the McMonnies ( p = 0.008; p < 0.001; respectively). In Method III ROC results were statistically significant for both the McMonnies ( p = 0.001) and OCI ( p = 0.005). The McMonnies showed the best prediction of Method I [0.646/10.5 (PPV/cut-off value)], while the OCI gave the best predictability in Method III only (0.518/30.6). Conclusion: A McMonnies scoring of ≥10.5 or an OCI scoring of ≥30.6 indicates CLIDE. The McMonnies performs better in prediction of CLIDE than the OCI. [ABSTRACT FROM AUTHOR]

Thus far there is little data available concerning Acanthamoeba associated amoebic keratitis (AK) from Italy. In order to understand the incidence of Acanthamoeba in patients with ocular infections and to characterize the isolates at the molecular level, ocular specimens and contact lenses or lens case solutions from 140 patients were analysed by culture and by an 18S rRNA ( Rns) gene-based PCR method. Nineteen (13.6%) patients showed Acanthamoeba culture positive samples. Eleven out of the 14 genetically characterized isolates were assigned to the T4 genotype. Three isolates, two of them from patients with keratitis responding to specific anti- Acanthamoeba therapy, were identified as belonging to the T15 genotype. This finding represents the first association between the T15 genotype and human amoebic keratitis. PCR amplification of the 18S ribosomal DNA proved to be a sensitive method, potentially able to detect Acanthamoeba without the need of long culture incubation, and thus considerably useful for clinical applications. [ABSTRACT FROM AUTHOR]

Contact lens hygiene has long been recognised as key to the prevention of contact-lens associated infection and inflammation. Microbial keratitis (MK) is the only serious and potentially sight-threatening contact lens adverse event. International studies including recent research in Asia Pacific show that MK is rare but, as the consequences can be severe, it is important to minimise the risk factors. Studies continue to show that one of the key risk factors is lens and lens case hygiene. Therefore, it is also useful to review the behaviour of our patients, to see how closely they follow the recommended hygiene practices. Recent studies in various regions have shown that patients’ lens care habits do not meet a required standard. Patients can become complacent and thus non-compliant with lens care instructions. Furthermore, they do not understand the high risk of some behaviour and they are not hearing the practitioner when instructions and reminders are given. Further education is important to improve patient compliance and safety. The Asia Pacific Contact Lens Care Summit held in Singapore urged the industry and practitioners to restore the emphasis of proper lens care, including the ‘rub and rinse’ technique, and developed a new set of guidelines to help eye-care professionals educate their patients on the importance of proper contact lens care to avoid eye infections. The summit also presented the latest research on how to avoid corneal staining, another important element of contact lens care. This review provides a summary of the summit presentations and the science behind these guidelines. [ABSTRACT FROM AUTHOR]

Purpose: To compare effectiveness of cleaning with and without rubbing of soft contact lenses. Methods: Three-hundred new biweekly disposable hydrogel lenses (Ocufilcon D, FDA Group IV; 55% water content) were artificially deposited with serum albumin, hand cream (semi-transparent deposits) and mascara (black deposits). The treated lenses were randomly divided into three groups, each group cleaned by one of three methods of cleaning — Rubbing (R), No-Rub following the manufacturer’s instruction on duration of rinsing (NR1) and No-Rub with a shorter duration of rinsing (NR2). Four commercially-available multipurpose solutions (MPS) and a saline were used. The cleaning effectiveness was determined by the amount of deposits remaining on the contact lenses after cleaning, assessed with the aid of a slit-lamp. The level of deposits remaining (in terms of coverage of lens surface) were determined using a five-point scale [0 (no observable deposits) – 4 (>80% deposits remained)] for semi-transparent deposits (protein and hand cream) and black deposits (mascara). The investigators were masked as to the solutions used (except for one MPS which has a different rinsing time than the other MPS), and the investigator who assessed the deposits left on the lenses did not know which solution or cleaning method was used to clean each lens. Results: Lenses cleaned by the R method were significantly cleaner than those cleaned by methods NR1 and NR2. No significant difference was found between lenses cleaned by NR1 and NR2 methods. The median grade of deposits for lenses cleaned by R method was 0.5 for both semi-transparent and black deposits. For lenses cleaned by NR1 and NR2 methods, the median grade of deposits left on lens surfaces was 4.0 for both types of deposits. Different solutions used did not affect the level of deposits left on lens surfaces for all three cleaning methods. Conclusions: Not rubbing the soft lens when cleaning is ineffective in removing loosely-bound deposits. A longer rinse, as recommended by the manufacturers, does not remove significantly more deposits than a shorter rinse with the MPS. This work supports the view that contact lens wearers should be encouraged to rub their lenses when cleaning. [ABSTRACT FROM AUTHOR]

The article presents a scenario by which a 25-year old right-handed male patient, who has been presented for a routine eye care, desiring contact lenses. The patient accordingly disclosed that he had been told he had a problem with his pupils and has been experiencing muscular parenthesis, which he described as jumping and twitching in his right hand fingers. Pupillary anomalies are said to be challenging due to its underlying cause that can range from benign conditions to potentially life-threatening disorders. It is further stated that patients with any pupillary abnormality, even without associated neurological symptoms, need to be further evaluated.

Abstract: Purpose: To investigate the quantity and severity of contact lens complications referred into Hull Royal Infirmary Ophthalmic A&E, their impact on resources and whether their management and treatment was appropriate. Methods: A survey was conducted over a 7-month period at Hull Royal Infirmary Ophthalmic A&E Unit. In this time 100 patients were enrolled, all completed a questionnaire including information about lens type and wearing schedule, and were photographed. All were examined, and where necessary treated by the Ophthalmic A&E doctor. Results: Contact lens complications accounted for 9.1% of the referrals into Ophthalmic A&E, a total of 323 appointments. Microbial keratitis was the most common diagnosis (22%), and Klebsiella and Pseudomonas the most common pathogen implicated. A case of Fusarium was also recorded. Optometrists/contact lens practitioners were the most common referral source (41%). Soft lens wearers were most common (67%), followed by silicone hydrogel wearers (28%) and least common were rigid gas permeable wearers (5%). Ten percent of the patients referred into the department were admitted. Conclusion: Education of the patient in their wear schedule and hygiene are still significant factors in their risk of developing contact lens complications. A closer working relationship needs to be fostered between Community Optometrists and Eye Departments to give the most appropriate management of contact lens related problems which would help alleviate undue burdens on Ophthalmic A&E. [Copyright &y& Elsevier]

Purpose: To evaluate postoperative healing between bandage contact lenses with high and low oxygen permeability in patients having photorefractive keratectomy (PRK). Setting: Center for Refractive Surgery, Walter Reed Army Medical Center, Washington, DC, USA. Methods: This retrospective study compared patients receiving a high-oxygen-transmission bandage contact lens (Focus Night & Day [N&D], Ciba Vision; n = 92) and those receiving a low-oxygen-transmission lens (Proclear, Cooper Vision; n = 114) after PRK. Visual outcomes, safety, and efficacy were assessed postoperatively at 1, 4, and 7 days and 1, 3, 6, and 12 months. Results: Overall pain scores were higher in the Proclear group at 1 day (P = .000) and 4 days (P = .027). The N&D group had an increase in corneal infiltrates at 4 days (P = .025) and 1 week (P = .017). At 1 month, 40.4% of patients in the Proclear group and 18.6% in the N&D group had a 1 or more line decrease in best spectacle-corrected visual acuity (BSCVA) (P = .002). Although there was a trend toward a higher haze rate in the Proclear group, it was not statistically significant (P = .064). There was no statistically significant difference in uncorrected visual acuity, goal of emmetropia, contrast sensitivity, or reepithelialization. Conclusions: The N&D lens produced less pain and better postoperative results in terms of haze and BSCVA at 1 month. However, it led to a higher incidence of corneal infiltrates. There was no difference between the lenses in the end result at 12 months. [Copyright &y& Elsevier]

Background: Several studies have suggested that bifocal and progressive spectacles can reduce progression of myopia in esophoric children. This study compared myopic progression with bifocal (BSCL) and single vision soft contact lenses (SVSCL) in identical twins with near point esophoria. Methods: Two 12-year-old myopic girls were randomly assigned to wear either BSCL or SVSCL for one year using a double-masked design. Both twins then wore BSCLs for another year. Ocular measurements included cycloplegic and manifest refractions, corneal curvature and axial length. Distance and near phorias were measured through distance corrections and near associated phorias, with both types of contact lenses. Results: Through their SVSCLs, both children exhibited near associated esophorias, which were neutralised by the BSCLs. The child wearing SVSCLs over the first year showed significant myopic progression, increasing -1.19 D (binocular average), while the child wearing BSCLs showed no progression (+0.13 D). The latter child showed limited progression (-0.28 D) over the second year, while switching from SVSCLs to BSCLs arrested progression in the other child (+0.44 D after one year). Axial length data were consistent with the refractive findings; the child exhibiting more myopia at the end of the first 12 months of the study had longer eyes (by 0.64 mm) than her sister, although their corneas also had steepened more (by 0.44 D compared to 0.18 D). The children showed similar, small increases in eye size over the second year when both wore BSCLs (binocular averages: 0.05, 0.09 mm, respectively). Conclusion: The apparent inhibitory effect of BSCLs on myopic progression reported in this twin study argues for further study of their efficacy as a control treatment for myopes with near esophoria. [ABSTRACT FROM AUTHOR]

Fitting a prism-ballasted soft toric contact lens unilaterally may potentially induce a vergence error that the subject cannot compensate. In the present study, a prism-ballasted (1.5Δ base down) soft toric contact lens was fitted in the right eye only of 10 subjects with normal binocular vision. The effect on binocular vision was evaluated by measuring vertical phoria adaptation and vertical fixation disparity adaptation. The results show that the vertical vergence error induced was well compensated and fully adapted to. However, care might be needed when fitting these lenses unilaterally in subjects with vertical phoria-related problems. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of two tinted contact lenses (CL) designed for outdoor sports activity on the psychometric determination of retinal straylight using the compensation comparison method. Methods: Thirteen emmetropic subjects were randomly fitted with two different tinted Nike Maxsight® (Bausch & Lomb, Rochester, NY, USA) CL in one eye, while the contralateral eye was fitted with a clear lens made of the same material (Optima 38, Bausch & Lomb). Three valid straylight measurements were taken on each eye before and a few minutes after lens insertion, when lens stabilization had occurred. Results: The subjects’ mean straylight values were 0.90 ± 0.09 at baseline and 0.95 ± 0.10 with the clear Optima 38 CL. Straylight values were 0.97 ± 0.10 and 1.0 ± 0.10 log units with the amber and grey–green tinted CL, respectively. Differences in straylight between baseline (without CL) and with the clear CL in place were neither statistically significant ( p = 0.066) nor was there a significant difference between baseline and the amber CL ( p = 0.052). However, the grey–green CL showed a statistically significant difference from baseline ( p = 0.006). Differences in straylight with the clear CL compared with the grey–green CL were also statistically different from zero ( p = 0.002) showing an increased straylight value for the tinted CL. These differences were variable, but consistent for each subject, thus those showing higher or lower changes with one tinted lens tended to show the same trend with the second lens ( r 2 = 0.736). Conclusions: Despite increases having been found in straylight values with tinted contact lenses, those changes are not likely to induce clinically significant changes in visual function under photopic conditions, even for the grey–green CL, which seems to increase straylight values more significantly than the amber CL. This difference between the tinted CL could suggest a wavelength dependence of straylight values, although this should be investigated further by controlling for pupil size and subjects’ pigmentation, as well as by using neutral density filters. [ABSTRACT FROM AUTHOR]

Objective: Contact lens wear is often associated with signs and symptoms of ocular dryness. These drying effects can be exacerbated by certain environmental factors such as low humidity, wind, and visual tasks. The objective of the study was to compare the ability of senofilcon A contact lenses to subjects'' habitual contact lenses to provide relief from the subjects'' perceived ocular discomfort during contact lens wear in adverse environmental conditions.Research design and methods: Eleven subjects completed a single-center, double-masked, randomized, cross-over, pilot clinical trial. At the qualification visit, and subsequently wearing senofilcon A study lenses (ACUVUE OASYS Brand Contact Lenses with HYDRACLEAR Plus*) and control (habitual) lenses at the following visits, subjects underwent a total of three 75-min Controlled Adverse Environment (CAE) exposures. The primary efficacy variable measured during the 2-week, 3-visit trial was subject-reported ocular discomfort during CAE exposure measured on a five-point scale from 0 (none) to 4 (worst). The endpoint of ocular discomfort was evaluated using a two-sided t-test based on a longitudinal linear mixed model. Lenses were also evaluated for safety, and all adverse events were monitored.Results: Subjects reported a significantly better mean comfort score when wearing senofilcon A contact lenses (1.62 ± 0.71 units) compared to the mean comfort score reported when wearing habitual lenses (2.21 ± 0.80 units) over the course of an entire CAE exposure (p = 0.0068). During exposure, senofilcon A lenses also yielded significantly better mean overall discomfort scores versus no lenses (2.73 ± 0.79 points, p < 0.0001).Conclusions: Senofilcon A contact lenses provided greater relief of subjective ocular discomfort associated with lens wear in adverse environmental conditions than that afforded by both the habitual lenses of contact lens wearers as well as with no contact lens wear. These results should be verified in a larger, appropriately-powered study. [ABSTRACT FROM AUTHOR]

This paper presents an elastohydrodynamic model of the human eyelid wiper. Standard lubrication theory is applied to the fluid layer between the eyelid wiper and ocular surface. The role of the lubrication film is to reduce the shear stresses by preventing solid to solid contact between the eyelid wiper and ocular surface. For the lubrication film to be effective, it is required that the orientation of the eyelid wiper changes between the opening and closing phases of a blink. In order to model this, the hydrodynamic model is coupled with an elastic mattress model for the soft tissue of the eyelid wiper and ocular surface. This leads to a one-dimensional non-linear partial differential equation governing the fluid pressure in the lubrication film. In order to solve the differential equation, a loading condition or constraint equation must be specified. The resulting system is then solved numerically. The model allows predictions of the tear film flux from under the upper eyelid, as well as normal and shear stresses acting on the ocular surface. These factors are important in relation to dry eye syndrome, deformation of the cornea and contact lens design. It is found that the pressure and shear stress under the eyelid act across a length of approximately 0.1 mm which is consistent with clinical observations. It order to achieve a flow of tears from under the upper eyelid during a blink, the model requires that the normal force the eyelid applies to the ocular surface during the closing phase of the blink is significantly higher than during the opening phase of the blink. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To study accuracy and safety, related to sensation (discomfort) and trauma, when using Goldmann applanation tonometry (GAT) on eyes wearing daily disposable soft contact lenses. Methods: The intra-ocular pressure (IOP) of 136 normal eyes of 68 subjects was measured by Goldmann tonometer. Measurements were made in one eye with a contact lens (hilafilcon A) without anaesthetic drops and then without the contact lens using one drop of 0.4% oxybuprocaine hydrochloride. Each contact lens used was identical as to back optic zone, back vertex power. Standard Goldmann procedure only was used for the fellow eye of each subject. Subjective sensation (discomfort) responses to both procedures were studied in a subgroup (66 eyes) using a scale of discomfort, from 1 (no sensation) to 5 (highest sensation). Epithelial staining after tonometry was evaluated for this subgroup. Results: No significant differences were found for the IOP with and without contact lens (t <1; p =0.63) for the IOP range studied. There was a good correlation between the two procedures (r =0.81; p <0.05). Lowest sensation was found with tonometry on the anaesthetized cornea; this condition was significantly different from other conditions (p <0.005). No difference was found among the other conditions (contact lens insertion, tonometry on contact lens and application of topical anaesthetic). Corneal epithelial staining following the standard tonometry procedure was significantly higher than following the procedure with a contact lens (p <0.00005). Conclusions: Measurement of IOP by GAT over a daily disposable soft contact lens is accurate, compared to the standard procedure and within the IOP''s normal range studied here. Also using a contact lens results in less trauma whilst discomfort is similar. [Copyright &y& Elsevier]

Abstract: Purpose: To explore the success of the application of a computerised videokeratography (CVK) software system for the fitting of rigid gas permeable (RGP) contact lenses (CLs) on irregular corneal surfaces and compare it to the standard diagnostic fitting procedure. Methods: This was a comparative prospective study, over a 1-year period (2004–2005). It included 41 RGP CL wearers (68 eyes) with irregular corneal surfaces. Of these, 51 (75%) had keratoconus, 7 (10%) corneal scarring (infectious or traumatic), 6 (6.82%) corneal transplants, 2 (2.9%) astigmatism, and 2 (2.9%) aphakia. Each eye was being re-fitted with a new RGP CL based on a topographical measurement in conjunction with a CL fitting software programme. The performance of the CLs was evaluated regarding visual outcome, fitting characteristics, and efficiency of the fitting procedure. Results: Of the 68 eyes, 53 (77.94%) chose the CL fitted using the CVK software system, 9 (13.24%) chose the CL fitted using the standard procedure, and 6 (8.82%) showed no preference for either CL. There was a statistically significant improvement regarding visual outcome [contrast sensitivity at the spatial frequencies of 0.66 (p =0.029), 3.40 (p =0.008), and 17 (p =0.032), subjective vision (p =0.009)], fitting characteristics [grading scale (p =0.00), lens comfort (p =0.00) and daily wearing time (p =0.002)], and efficiency [number of trial lenses required (p =0.00)] with the CL fitted using the CVK software system. Correlating factors for the likely preference for the CL fitted using the CVK software system were subjective vision (p =0.004), lens comfort (p =0.009), and convenience of the fitting procedure (p =0.023). Conclusion: The application of a CVK software system for the fitting procedure of RGP CLs on irregular corneal surfaces was a safe procedure and shown to be more successful and efficient than the standard diagnostic fitting method. [Copyright &y& Elsevier]

We describe a case of severe craniofacial trauma with resultant exposure keratopathy that was refractive to traditional treatment measures including aggressive lubrication, tarsorrhaphy, platinum lid weight implantation, punctal plugs, correction of lid retraction, amniotic membrane application, and multiple bandage contact lenses. Through combined Boston scleral lens placement and traumatic cataract extraction with intraocular lens (IOL) implantation using scleral lens IOL power calculations, we were able to maximize patient comfort and attain superior visual acuity. To our knowledge, calculation of IOL power through a scleral lens has not been described. [Copyright &y& Elsevier]

Purpose: The aims were to determine the level of compliance of contact lens wearers, to identify which procedures have highest levels of non-compliance and to study the effectiveness of a compliance enhancement strategy on the level of compliance. Methods: The level of compliance for each subject was evaluated with a self-administered questionnaire together with microbiological examination of their contact lenses, lens cases and lens care solutions. The effect of an intervention to improve the level of compliance was determined by a controlled trial. A regular self-review exercise on proper lens handling was given to the test group once every three months for 12 months. The levels of compliance and contamination of contact lenses and lens care accessories between test and control groups were compared at the end of the 12-month period to evaluate the effect of the intervention. Results: Sixty-five subjects who were experienced contact lens wearers were recruited and 60 completed the study. All showed some degree of non-compliance in the care of their contact lenses and lens accessories. Most (about 60 per cent) were non-compliant with at least six of a total of 15 lens care procedures. The most common non-compliant behaviour among contact lens wearers was associated with the care of the lens case. By the end of the study period, our compliance enhancement strategy did not appear to have had a significant effect on the behaviour of our subjects, except for improvement in the care of lens cases. Compliance for other procedures improved in both test and control groups. Conclusion: All subjects showed some degree of non-compliance and the spectrum of non-compliance was wide. The poorest levels of compliance were associated with care of the lens case, which was also the most frequently contaminated item. Our compliance enhancement strategy showed a significant difference in improvement in compliance between the intervention and control groups only in the care of lens cases. [ABSTRACT FROM AUTHOR]

Purpose: To characterize the prevalence and natural course of retinoschisis in a 14-year follow-up study. Design: Population-based cohort study. Participants: Nine hundred forty-six residents, aged 60 to 80 years, living in the Østerbro district of Copenhagen, participated in the prevalence study from 1986 to 1988. Excluding participants who died since baseline, 359 persons (97.3% of survivors) were reexamined after 14 years from 2000 to 2002. Of the 946 participants, 35 persons had prevalent retinoschisis in 1 or both eyes at baseline and 15 of these persons were alive at follow-up. Methods: Participants underwent an extensive ophthalmologic examination at Rigshospitalet, the National University Hospital of Copenhagen. Standardized protocols for the ophthalmologic examination included retinal evaluation by use of Goldmann’s 3-mirror contact lens and ultrasonic B-scan of the retina. Data for the 20 persons who died were obtained from the National Patient Register and the National Central Person Register. Main Outcome Measures: The prevalence, presence, disappearance, and progression of peripheral retinoschisis over a period of 14 years. Results: The age-standardized prevalence of retinoschisis was 3.9% (95% confidence interval, 2.6–5.2) in persons aged 60 to 80 years. Gender and increasing age at baseline were not associated with the presence of retinoschisis. The retinal quadrant of maximal involvement was the inferior temporal (44.4%). One case of symptomatic progressive retinal detachment occurred during follow-up (2.2%). This was preceded by cataract surgery. Four persons developed retinoschisis in the contralateral eye during follow-up; therefore, the incidence of retinoschisis was 16% and bilaterality was 57.1% at follow-up. However, in 14 persons (73.7%) the retinoschisis remained unchanged. The disappearance rate was 8.8% (n = 4). Conclusions: These findings indicate that senile retinoschisis primarily is bilateral, asymptomatic, and nonprogressive and should not be treated routinely. Cataract extraction is a possible risk factor for progressive retinal detachment. [Copyright &y& Elsevier]

Purpose: The present paper describes an accurate and cost-effective method requiring simple equipment to measure the oxygen permeability and transmissibility of contact lenses. Method: The method involves accurate measurement of oxygen across the material by allowing the gas (oxygen) to pass through the lens material in a specially fabricated lens mould. The expelled gas is collected by dissolution in ethanol and the oxygen is measured by titration of the solvent. Result: This method is suitable for the measurement of oxygen permeability and transmissibility of contact lenses of varying thickness and different radii of curvature. It can measure Dk and Dk/t of collagen bandage lenses in both wet and dry conditions. Conclusion: The oxygen permeability and transmissibility values obtained by this method were compared with the oxygen permeability standard values of commercially available contact lenses and the results are summarised. [ABSTRACT FROM AUTHOR]

Abstract: Orthoptic anomalies are prevalent: they are encountered in at least 5% of patients seen in a typical primary eyecare practice. Several cases are reviewed that highlight the role of contact lenses in treating orthoptic anomalies. In particular, contact lenses are the preferred optical approach to the correction of anisometropia, and it is often argued that anisometropia should be corrected as young as possible. However, fitting contact lenses to patients, particularly children, with anisometropic amblyopia has been problematic because there is no immediate binocular acuity improvement when the contact lenses are inserted which reduces patient motivation. Continuous wear with silicone hydrogels represents a breakthrough for these cases and some illustrative case studies are given. The visual deficit in amblyopia can be reduced in some cases solely by fitting contact lenses, without the need for occlusion therapy. Other orthoptic uses of contact lenses are reviewed including: correcting motor deviations, occlusion, and infantile onset nystagmus. It is concluded that there are orthoptic anomalies where contact lenses are the preferred mode of correction. It is in patients’ best interest for practitioners to discuss contact lenses in these cases. [Copyright &y& Elsevier]

Aims: To determine the frequency of choroidal detachment (CD) in eyes with non-traumatic corneal ulcer perforation and, also, to assess the efficacy and safety of cyanoacrylate glue in sealing corneal perforations. Methods: 18 eyes of 17 patients were studied. Inclusion criterion was any patient with a non-traumatic perforated corneal ulcer. All patients had a thorough history taken and complete ophthalmic examination including B-scan ultrasonography. Patient demographics, presence of CD, and efficacy of corneal gluing were assessed. Results: Eight of the 18 eyes (44%) were documented to have a CD. Among perforations of >2 mm2, six eyes (75%) were documented to have CD compared with two eyes (20%) with perforations of ⩽2 mm2 (p=0.054). No correlation could be determined between perforation duration and incidence of CD. Of the 15 eyes that underwent gluing, there were 13 successes (87%) and two failures (13%). Within the successes four patients (27%) required re-gluing because of infection (one patient) or progression of melt and glue loosening (three patients). Failure was the result of severe progression of melting (one patient) and a very large perforation (one patient). Conclusion: Choroidal detachment following corneal ulcer perforation is common and is more likely in larger corneal perforations. Preoperative B-scan should be considered in cases of large corned perforations requiring therapeutic keratoplasty to document choroidal detachment, which if large may require drainage. Cyanoacrylate glue is an effective and safe method for sealing small corneal perforations. A vigil must be maintained for infection while the glue and bandage contact lens are in situ. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate age-related position shifts of the crystalline lens and the implantable contact lens (ICL, Staar Surgical) by a new, commercially available, anterior segment partial coherence interferometer, the ACMaster (Carl Zeiss Meditec), during accommodation in myopic eyes. Setting: ALZ Augenklinik, Munich, Germany. Methods: Fifty-three eyes of 29 consecutive patients were measured after myopic ICL implantation before and during subjective accommodation to a stimulus of 3 diopters (D) by anterior segment partial coherence interferometry (PCI). Nine eyes were also measured with a 5.00 diopters (D) stimulus; 14 eyes were measured repeatedly at different visits. The mean patient age was 33 years ± 9 (SD) (range 21 to 59 years). The preoperative mean sphere was −7.6 ± 1.9 D (range −5.0 to −11.5 D) and the cylinder, −1.4 ± 1.1 D (range 0 to −4.25 D). Results: Older patients had a tendency toward smaller vaults on desaccommodation between the ICL and the crystalline lens compared to younger individuals. In younger patients, there was a decrease of the vault on accommodation, whereas it increased in older persons (P = .005). During accommodation, the more the anterior lens surface shifted forward, the more the ICL bulged (P = .005). The change in vaulting was significantly larger at 5.00 D than at 3.00 D accommodation stimulus (P = .012). Conclusions: The behavior of ICLs in relation to the crystalline lens during accommodation varied with age and could be shown by PCI. The position shift of the ICL depended on the initial vault at desaccommodation and the ability of the anterior lens surface to bulge forward. Even though the crystalline lens stiffened, and therefore accommodation deteriorated with age, there was still a movement of the ICL, pointing to the role of the ciliary muscle movement in accommodation. [Copyright &y& Elsevier]

Purpose: To assess topography-assisted corneal wavefront excimer laser surface ablation for the correction of ametropia and irregular astigmatism after keratoplasty. Setting: Department of Ophthalmology, St. Thomas'' Hospital, London, United Kingdom. Methods: In this pilot study, 15 patients (16 eyes) who were intolerant of spectacle and contact lens correction due to astigmatic anisometropia after keratoplasty (15 penetrating and 1 lamellar) had topography-assisted customized excimer laser treatments. Corneal topographic data using a Keratron Scout, Placido disk system allowed for preoperative analysis of wavefront anomalies of the anterior corneal surface from which a customized excimer laser correction of both lower-order aberrations (LOAs) and higher-order aberrations (HOAs) was prepared (ORK software) for treatment with a Schwind Esiris flying-spot laser. All eyes had laser-assisted subepithelial keratectomy (LASEK) using 15% alcohol with a 20-second to 30-second application. Four eyes received an application of mitomycin-C (MMC) 0.2 mg/mL for 1 minute after stromal ablation. Results: The mean preoperative spherical equivalent (SE) was −3.50 diopters (D) ± 3.97 (SD) (range +1.625 to −9.25 D). The preoperative cylindrical error was −7.2 D (range −2.75 to −13.5 D). The programmed laser correction was −3.14 D (range +1.62 to −9 D) with a maximum attempted cylindrical correction of −7 D. Adherent LASEK epithelial flaps along suture lines and the graft–host junction were noted in 9 eyes (56%), although it was possible to obtain and replace a partial flap. A follow-up of 18 months was achieved in all eyes. At the final follow-up visit, the mean postoperative SE was −1.08 ± 1.85 D (range +3 to −4.78 D) (P<.01, F<.01). Ten eyes (62.5%) were within ±1 D of the intended correction. The mean postoperative cylindrical error was −2.72 D (range −0.5 to −6.5 D) (P<.001), with vector analysis demonstrating a mean 6.23 D correction. Analysis of HOAs using a 6.0 mm pupil size demonstrated a significant reduction of higher-order root mean square (RMS) (P<.002), trefoil (P<.005), and 4th-order spherical aberration (P<.02) at 18 months compared with preoperative values. Uncorrected visual acuity improved in all eyes (P<.0001). Best spectacle-corrected visual acuity was unchanged or improved in 13 eyes (81%) and worse in 2 eyes by 1 line; 1 eye lost 3 lines due to an increase in preexisting cataract. In eyes that did not receive MMC, corneal haze (grade II to IV) was encountered in 3 eyes (27%). One eye required phototherapeutic keratectomy with MMC application at 12 months. Of the 4 eyes treated with MMC, 1 had trace haze and 3 had no detectable haze. There were no reported cases of epithelial instability, ectasia, or graft rejection. Conclusions: Topography-assisted customized LASEK was effective in the correction of postkeratoplasty astigmatism. A significant improvement of both LOAs and HOAs was obtained with good refractive stability for over 18 months. Iatrogenic haze typically occurred but appeared to be minimized with adjunctive use of intraoperative MMC. [Copyright &y& Elsevier]

A 39-year-old woman developed corneal ectasia after laser in situ keratomileusis. Intracorneal ring segments (Intacs, Addition Technology, Inc.) were placed in the left eye in November 2004. Postoperatively, inferior topographic steepening decreased significantly and a rigid gas-permeable lens yielded 20/25 visual acuity. However, the patient reported persistent discomfort that did not improve with topical medications or a bandage contact lens. In May 2005, confocal microscopy demonstrated a corneal nerve in direct contact with the inferior segment. Both segments were removed, and after removal, the patient reported complete resolution of the pain. [Copyright &y& Elsevier]