Discipline of Optometry and Vision Science

 Data from scheduled study visits and a 2 month telephone questionnaire were analysed using chi-square tests and linear mixed model analyses. Figure 2: Reasons for discontinuation Reason DC (Non-AR) beyond baseline Count % Biomicroscopy 0 0% Discomfort 9 10% Handling 1 1% Symptoms & Problems 5 6% Unacceptable Fit 1 1% Unacceptable Subjective 4 5% Other Product Related 4 5% Unrelated medical problem 1 1% Time/Job Conflict 13 15% Disinterest 6 7% Relocated 5 6% Lost to Follow-Up 16 18% Other Non Product Related 13 15% Unknown 10 11% Total 88 100%

To investigate the incidence of adverse events related to the use of varying silicone hydrogel contact lens and lens solution combinations. Methods: Individuals with myopia (N = 558) participated in 1 or more of approximately 40-participant trials in a matrix of 20 silicone hydrogel contact lens and lenssolution combinations. Visits were at baseline, 2 weeks, 1 month, and 3 months. The mean study completion rate was 90% of the expected participant-months (final data set: 840 lens-solution combinations and 2271 participantmonths). Adverse events were reported as the first occurrence of each type per 100 participant-months for each lens-solution combination. Results: The rate of all corneal infiltrative events (CIEs) was 3.1 per 100 participant-months (range, 0-10.5), and the rate of symptomatic CIEs was 1.7 per 100 participantmonths (range, 0-10.5), including 1 case of microbial keratitis (0.04 per 100 participant-months). Rates for CIEs differed substantially among solution groups, with hy-METHODS Data were collected from a series of ongoing, nonrandomized, open-label-dispensing clinical studies conducted at the Institute for Eye Research. All studies followed the same pro

To determine whether risk taking personality is associated with compliance in contact lens wear, and how practitioner perception of compliance compares with wearer risk taking and non-compliant behaviour. Method: Optometrists in Australia, recruited through professional organizations, were asked to enroll up to 10 current contact lens wearers each. Wearers completed a questionnaire assessing risk-taking propensity (20-item instrument), non-compliant behaviour and demographics. Non-compliance was scored on four components (maximum score 40, lens disinfection, 20; hand hygiene, 8; case hygiene, 6; case replacement, 6). Independently, practitioners ranked each wearer's non-compliance on a 1-5 scale. Associations between wearer risk taking propensity, non-compliant behaviour and practitioner perceived non-compliance were investigated using Pearson correlation. Significant associations were entered into a linear regression model predicting overall non-compliant behaviour. Results: Seventy-three wearers were recruited by 18 optometrists (mean 4, range 1-10). Wearer risk taking was associated with less compliance (p < 0.01) as was younger age (p < 0.01) and male gender (p = 0.02). Years of lens wear was not associated with non-compliant behaviour (p = 0.8), nor was practitioner perception of compliance (p > 0.6) Linear regression indicated that risk taking was the only independent significant factor predicting non-compliance, explaining 24% of the variation in behaviour. Conclusion: A higher risk taking personality style of contact lens wearers in Australia is associated with less compliant behaviour. Risk taking is a better predictor of compliance than age, gender and practitioner perception and helps explain the individual characteristics of wearers that may influence lens care and maintenance.

Purpose. Microbial keratitis (MK) is a serious sight-threatening complication occurring with and without contact lens wear. The task of diagnosing MK is difficult because each presentation of the disease is different and can be mistaken for noninfectious ulcers such as contact lens peripheral ulcer (CLPU). The purpose of this article is to present a case report of MK initially diagnosed as a CLPU. Case Report. We report the incidence of a 21-year-old female presenting with signs and symptoms in her left eye, which initially suggested a CLPU. At the 24-h follow-up, contrary to expected indications of healing, her condition had deteriorated. The diagnosis was reevaluated as an MK. Ciloxan was prescribed under care of an ophthalmologist. Despite initial misdiagnosis, due to aggressive topical treatment and the peripheral location of the lesion, Ͻ1 line of vision was lost. Discussion. Defined signs and symptoms criteria have been established for the differential diagnoses of MK and CLPU. However, there is often an overlap in the signs and symptoms that can complicate the diagnosis. A critical sign, however, is progress immediately after lens wear is discontinued. Prophylaxis and rapid appropriate treatment and follow-up are vitally important if there is any doubt and to ensure correct diagnosis and resolution. Conclusion. Any diagnosis of CLPU must be monitored carefully to ensure it is not MK. Prompt diagnosis and treatment of MK are essential for a good visual outcome.

Purpose. Contamination of contact lens cases has been associated with the production of adverse responses in the eye during contact lens wear. This study aimed to evaluate the contamination rate and types of microbes contaminating cases during use of contact lens disinfecting solutions and silicone hydrogel lenses. Methods. Two hundred thirty-two participants were allocated to one or more groups. The participants wore one or more of three silicone hydrogel lenses and used one or more of four contact lens disinfecting solutions. Cases were collected after use for 1 month and sent for routine microbial testing. The rate of contamination of cases and the types of microbes contaminating cases were evaluated. Results. Between 76 and 92% of all cases were contaminated. Use of different contact lenses did not affect contamination rate or the types of microbes isolated from cases. Use of AQuify (PHMB as disinfectant) was associated with the highest contamination rate (92%; p ϭ 0.015) of cases for any microbe. Level and type of contamination with use of ClearCare (H 2 O 2) was similar to use of PHMB (polyhexamethylene biguanide)-or Polyquat/Aldox-containing solutions. There was no difference in contamination rate of cases by fungi or Gram-positive bacteria, but for Gram-negative bacteria, use of Opti-Free Express (Polyquat and Aldox as disinfectants) resulted in a lower contamination rate (7% vs. 29 to 45%; p Ͻ 0.001). The average number of microbes contaminating a case was significantly less for Opti-Free Express (223 Ϯ 1357 cfu/case) compared with Opti-Free RepleniSH (Polyquat and Aldox as disinfectants; 63,244 Ϯ 140,630 cfu/case; p Ͻ 0.001), driven mostly by differences in numbers of Gram-negative bacteria, particularly contamination by Delftia acidovorans in cases exposed to Opti-Free RepleniSH. Conclusions. Different disinfecting solutions used during storage in cases result in different levels of contamination and contamination by different types of microbes. These differences are not simply because of the types of disinfectants used, suggesting that other excipients in, or formulation of, the solution affect contact lens storage case contamination.

Purpose. To determine risk-taking propensity of optometrists and the association with the volume of contact lens practice and prescribing profile. Other factors associated with high practitioner risk taking and larger volume contact lens practices were also investigated. Methods. Sixty-four practitioners were recruited through Australian professional associations. Practitioners completed a risk-taking propensity survey and rated the importance of risk factors for contact lens-related microbial keratitis on prescribing decisions and wearer advice (prescribing profile). Demographics and the number of contact lens wearers seen per week were documented. Risk-taking propensity was estimated after adjusting for item difficulty using Rasch analysis, then scaled 0 to 100. Prescribing profile, practice type, practitioner age, and gender were tested for association with risk-taking propensity. Risk-taking propensity, practitioner age, personal contact lens wear, and the socioeconomic status of the practice location were investigated for association with the volume of contact lens patients with regression. Results. Rasch analysis of the risk-taking questionnaire indicated good person separation and reliability (2.44, 0.86) but some item redundancy (1.69, 0.74). Risk taking (mean 35, range 0 to 71) was associated with increasing number of contact lens patients (p ϭ 0.02). The perceived importance of risk factors (p ϭ 0.9) and likelihood of discussing them with patients (p ϭ 0.7) were not associated with risk-taking propensity. Risk taking (p ϭ 0.02) and socioeconomic status of the practice location (p ϭ 0.03) were predictors of higher volume contact lens practices. Conclusions. Practitioners who see a higher volume of contact lens patients tend to have higher risk-taking personalities. However, increased risk taking did not affect the perceived importance and type of advice given to contact lens wearers. Higher socioeconomic status of the practice location is also associated with larger volume of contact lens patients. This information gives insight into what drives higher volume contact lens practice within Australia and may have applications to the contact lens and wider optical industry.

Purpose. Lipocalin is a major regulated protein in human tear fluid. This protein is a lipid carrier and has been associated with the stability of the tear film, and increased concentration of lipocalin in tears is associated with intolerance to contact lens wear. We examined the isoforms of lipocalin in a group of people to see if these altered with age or gender, or were related to differences in tear film volume/tear production rate. Methods. Six males and 6 females were recruited into the study with age range from 23-51 yrs. Tear film volume was measured using the Phenol Red Thread test (PRTT). Tears were collected by capillary, concentration of lipocalin measured by inhouse ELISA, and isoforms separated by 2D-gel electrophoresis. MALDI-TOF-MS was used to identify the isoforms and also provided evidence of the nature of the isoforms. Results. The PRTT was generally similar across gender and age, although the oldest subject had a lower (0.9 mm/sec) tear production rate/volume. The concentration of lipocalin was on average 1.3 mg/ml and was not altered with age or gender. The number of isoforms identified ranged from 7-12 after 2D-gel electrophoresis. Most subjects had 7 isoforms. 1 subject only had 12 isoforms, this subject was female and the oldest subject. The isoforms of lipocalin ran as 2 chains with differing mass and charge. Several potential modifications were noted, including endogenous tear exopeptidase digestion, glycosylation, methylation, amino acid substitution, and palmitoylation. Conclusions. This study has identified several isoforms of lipocalin. These were not the product of storage or other methodological considerations. The isoforms of lipocalin did not contribute to differences in lipocalin concentration nor to changes in tear stability/volume. However, these isoforms may exhibit differences in binding of lipids.

Over the last 20 years, there have been marked improvements in the availability of effective medications for rheumatic conditions such as gout, osteoporosis and rheumatoid arthritis (RA), which have led to a reduction in disease flares and the risk of re-fracture in osteoporosis, and the slowing of disease progression in RA. However, medication adherence remains suboptimal, as treatment regimens can be complex and difficult to continue long term. Many trials have been conducted to improve adherence to medication. Core domains, which are the outcomes of most relevance to patients and clinicians, are a pivotal component of any trial. These core domains should be measured consistently, so that all relevant trials can be combined in systematic reviews and meta-analyses to reach conclusions that are more valid. Failure to do this severely limits the potential for trial-based evidence to inform decisions on how to support medication adherence. The Outcome Measures in Rheumatology (OMERACT...

Purpose. Microbial keratitis (MK) is a serious sight-threatening complication occurring with and without contact lens wear. The task of diagnosing MK is difficult because each presentation of the disease is different and can be mistaken for noninfectious ulcers such as contact lens peripheral ulcer (CLPU). The purpose of this article is to present a case report of MK initially diagnosed as a CLPU. Case Report. We report the incidence of a 21-year-old female presenting with signs and symptoms in her left eye, which initially suggested a CLPU. At the 24-h follow-up, contrary to expected indications of healing, her condition had deteriorated. The diagnosis was reevaluated as an MK. Ciloxan was prescribed under care of an ophthalmologist. Despite initial misdiagnosis, due to aggressive topical treatment and the peripheral location of the lesion, Ͻ1 line of vision was lost. Discussion. Defined signs and symptoms criteria have been established for the differential diagnoses of MK and CLPU. However, there is often an overlap in the signs and symptoms that can complicate the diagnosis. A critical sign, however, is progress immediately after lens wear is discontinued. Prophylaxis and rapid appropriate treatment and follow-up are vitally important if there is any doubt and to ensure correct diagnosis and resolution. Conclusion. Any diagnosis of CLPU must be monitored carefully to ensure it is not MK. Prompt diagnosis and treatment of MK are essential for a good visual outcome.

Purpose. Contamination of contact lens cases has been associated with the production of adverse responses in the eye during contact lens wear. This study aimed to evaluate the contamination rate and types of microbes contaminating cases during use of contact lens disinfecting solutions and silicone hydrogel lenses. Methods. Two hundred thirty-two participants were allocated to one or more groups. The participants wore one or more of three silicone hydrogel lenses and used one or more of four contact lens disinfecting solutions. Cases were collected after use for 1 month and sent for routine microbial testing. The rate of contamination of cases and the types of microbes contaminating cases were evaluated. Results. Between 76 and 92% of all cases were contaminated. Use of different contact lenses did not affect contamination rate or the types of microbes isolated from cases. Use of AQuify (PHMB as disinfectant) was associated with the highest contamination rate (92%; p ϭ 0.015) of cases for any microbe. Level and type of contamination with use of ClearCare (H 2 O 2) was similar to use of PHMB (polyhexamethylene biguanide)-or Polyquat/Aldox-containing solutions. There was no difference in contamination rate of cases by fungi or Gram-positive bacteria, but for Gram-negative bacteria, use of Opti-Free Express (Polyquat and Aldox as disinfectants) resulted in a lower contamination rate (7% vs. 29 to 45%; p Ͻ 0.001). The average number of microbes contaminating a case was significantly less for Opti-Free Express (223 Ϯ 1357 cfu/case) compared with Opti-Free RepleniSH (Polyquat and Aldox as disinfectants; 63,244 Ϯ 140,630 cfu/case; p Ͻ 0.001), driven mostly by differences in numbers of Gram-negative bacteria, particularly contamination by Delftia acidovorans in cases exposed to Opti-Free RepleniSH. Conclusions. Different disinfecting solutions used during storage in cases result in different levels of contamination and contamination by different types of microbes. These differences are not simply because of the types of disinfectants used, suggesting that other excipients in, or formulation of, the solution affect contact lens storage case contamination.

Victoria e evans 1 , nicole a carnt 1 , thomas J naduvilath 1 , Brien a holden 1,2 results introduction  Discomfort, dryness, redness, poor vision and shorter wear time are associated with drop out from low Dk soft lens daily wear (Pritchard et al 1999, Young et al 2002)  Refitting with silicone hydrogel lens can alleviate some of these problems (Riley et al 2006, Dumbleton et al 2006)  However, drop out from silicone hydrogel lens wear still occurs so we investigated to see if the same factors were leading to discontinutation in silicone hydrogel lens daily wear (SiHy DW).  The discontinuation rates reported here may not be directly applicable to practice population as many discontinuations may have been for specific clinical trial causes.  Participants who discontinued at baseline were not included in the analysis so their reasons for discontinuation may be under represented.