Clinical Optometry最新文献

Smartphones are less likely to be considered as assistive technology for visual impairment among a large majority of health care providers, excluding vision rehabilitation professionals, and the general public who are not familiar with accessible features and apps. The present review aims to highlight accessible features and apps along with usages, including educational, and access to smartphones as assistive technology for visual impairment and blindness. It also includes advantages and challenges faced by users, and usability testing by app developers. There have been significant recent developments in mobile technology that incorporate computer technology relating to electronic information, communication, and touch-screen accessibility. Such advances in technology are transforming the use of smartphones from a traditional visual interface to a truly visual free interaction using alternative body senses, such as haptic, gesture, and so on. There are many built-in accessible features and third-party accessible applications that enable people with visual impairment to perform daily activities, independent functioning, movement, social inclusion and participation, education, etc. They are universally designed, so they are unlikely to induce social stigma or negative reactions from peers or public. Healthcare practitioners, not limiting to eye care, and caregivers, family members, teachers, or special educators should be informed about the potential uses and benefits of smartphones for visually impaired in developing nations. Evidence shows that most of the users train by themselves. Enhancing the awareness along with training for teachers and caregivers would be helpful to improve access and skills among users with visual disabilities. Developers are continuously producing more innovative applications for visual impairment, which indicates the need for having a training guideline on the use of smartphones.

CHARGE syndrome is a rare genetic disorder associated with many ocular anomalies including amblyopia, strabismus and high refractive errors. It has been found that the visual acuity of patients with CHARGE syndrome is typically lower than 20/60. After reviewing the literature, there has been a lack of detailed information about the assessments of visual function. Thus, this case report illustrates the strategy plan to treat amblyopia and refractive correction for a young girl with CHARGE syndrome.

Purpose: To collect the normal value data of corneal hysteresis in Thais and study the variation of corneal hysteresis in glaucomatous eyes.

Methods: Retrospective cross-sectional study of corneal hysteresis (CH) in healthy non-glaucomatous and glaucomatous eyes. Demographic data, type and staging of glaucoma, Goldmann applanation tonometry (GAT) and ocular response analyzer parameters; CH, corneal-compensated intraocular pressure (IOPcc) and Goldmann-correlated intraocular pressure (IOPg) were collected.

Results: Data from one eye of 465 normal participants were included for the normal value data of CH. Mean CH, IOPcc and IOPg were 10.18 ± 1.48, 15.01 ± 3.04 and 14.16 ± 3.06 mmHg, respectively. Average age was 57.21 ± 14.4 years. CH at the fifth percentile was 8.0 mmHg. Women had significantly higher CH than men (10.29 ± 1.46 vs 9.90 ± 1.49 mmHg, p=0.009). Moderate negative correlation was found between age and CH, r = -0.338, p<0.001. There were 695 glaucomatous eyes from 429 patients including primary-open angle glaucoma (POAG), primary close-angle glaucoma (PACG), normal tension glaucoma (NTG) and ocular hypertension (OHT). CH in each glaucoma type and severity stage (early, moderate and severe) were as follows: POAG: 8.74 ± 1.52 mmHg (9.22 ± 1.47, 8.74 ± 1.23 and 7.92 ± 1.40 mmHg, p<0.001), PACG: 9.09 ± 1.72 mmHg (9.85 ± 1.45, 9.04 ± 1.68 and 8.45 ± 1.74 mmHg, p= 0.004), NTG: 9.55 ± 1.67 mmHg (9.47 ± 1.38, 9.75 ± 2.42 and 9.77 ± 1.34 mmHg, p 0.525) and OHT: 10.10 ± 1.40 mmHg.

Conclusion: Compared with normal value data of corneal hysteresis, CH in glaucomatous eyes was lower. The more advanced glaucoma stage was associated with lower CH. Arising from normal value data, a low percentile of CH could be applied as the deviation value from normal and this dynamic property of CH could represent a glaucoma predictor in an effort to improve glaucoma care.

Purpose: Preservatives are essential for preventing contact lens (CL)-related microbial keratitis (MK). The purpose of this review is to summarize the current knowledge related to the use of common ophthalmic preservatives in CL care products with respect to both safety and efficacy.

Methods: Manuscripts written in English were obtained by searching PubMed.gov with the term contact lens plus antimicrobial, benzalkonium chloride, biguanide, Aldox, polyquaternium, preservative, thimerosal, EDTA (ethylenediaminetetraacetic acid), chlorhexidine, or blister pack.

Results: This review found that first-generation preservatives are no longer used in CL multipurpose solutions (MPS) due to their high levels of ocular toxicity. Modern, high-molecular-weight preservatives, including polyquaternium-1 (PQ-1) and biguanides (PHMB), are generally effective against bacteria, minimally effective against fungi, and not effective against Acanthamoeba. PQ-1 and PHMB are likely safe when used with CLs, but they may cause ocular adverse events, with roughly equal risk between the two preservatives. Some CL MPS contain both PQ-1 and PHMB, but no increased risk of adverse events has been reported when combining the two. Hydrogen-peroxide (H₂O₂) solutions are effective against all common ocular microbes, including Acanthamoeba, and they have been proven safe with proper compliance. Povidone-iodine (P-I) solutions are not currently commercially available in North America, but they have been shown in other countries to be safe and effective.

Conclusion: Patients should be monitored when using PQ-1 or PHMB-containing solutions since they have been associated with ocular adverse events. If events are detected, patients should be switched to an alternative solution. H₂O₂ or P-I solutions are preferred for any patient who may expose their CLs to water because they are the only solution categories effective against Acanthamoeba.

Background: Cataract is the leading cause of avoidable blindness globally and in Africa. Various barriers limit access of cataract blind individuals to cataract surgery. This study aimed to determine the barriers to cataract surgery utilization among cataract blind patients presenting to campaign sites in Ethiopia.

Methods: An institution-based cross-sectional design study was conducted to select 209 patients. The study was conducted from July to August 2020. A structured questionnaire was used to collect socio-demographic data and barriers for not having cataract surgery. Physical examination such as visual acuity, slit lamp bio microscopy and direct ophthalmoscopy was done for all participants. Epi Info 7 was used for data entry and Statistical Package for Social Science/SPSS version 23 was used for analysis after data were exported. Descriptive methods were employed for analysis.

Results: A total of 209 subjects were recruited in the study with a mean age of 64.2 (±14.6) years, with a range of 32-99 years. From the total study subjects, 53% were males and 40.2% were over 66 years old. Upon presentation to the campaign site, 33% of study subjects had visual acuity of operable eye under blindness category and half of the study subjects (50.2%) had mature cataract. The most reported barriers were waiting until cataract becomes mature (18.7%), fear of surgery complications (16.7%), far from eye health institution (16.4%) and lack of income/cost for surgery (11.5%).

Conclusion: Recognizing the severity and the blindness burden of cataract in Ethiopia, creating public awareness, establishing eye health institutions, increasing the number of eye health professionals, increasing the quantity and the quality of cataract campaigns to alleviate these barriers are of paramount importance at the country level.

Purpose: The purpose of the present study is to determine the effects of type 2 diabetes mellitus on tear osmolarity using a TearLab Osmolarity system. Moreover, the relationship between tear film osmolarity and ocular surface discomfort in controlled and uncontrolled diabetic patients was assessed.

Materials and methods: This study included 20 male type 2 diabetic patients aged 20 to 70 years (mean ± SD 49±12). A control group (18-43 years; 32.2 ± 6.5 years) consisting of 40 male subjects was also enrolled for comparison. The tear osmolarity was measured using the TearLab Osmolarity System. The ocular surface disease index questionnaire (OSDI) was used to assess ocular discomfort symptoms.

Results: The mean tear osmolarity was 297 ± 8.00 and 296 ± 11 mOsm/L for controlled and uncontrolled diabetic subjects, respectively, while the average osmolarity in the control group was 299 ± 8.00 mOsm/L. No significant differences were detected in tear osmolarity between the control and diabetes groups. The ocular surface disease index questionnaire (OSDI) score was significantly higher in the diabetic patient group. No significant correlation was found between tear osmolarity and OSDI scores.

Conclusion: The ocular discomfort symptoms score in diabetic patients was significantly higher compared to normal eye subjects. Tear osmolarity was not significantly different in diabetic patients. This finding may be explained by a lack of relationship between tear film parameters and diabetic severity; tear film parameters may correlate more with diabetic duration rather than severity. Therefore, studies focused on diabetes duration and tear film parameters are recommended.

Background: Pseudoexfoliation syndrome is an age-related disorder characterized by the deposition of a distinct fibrillar extracellular material in various tissues and organs of the body. Glaucoma and cataract are the consistently reported clinical consequences of Pseudoexfoliation syndrome on the eye. This study aimed to estimate the proportion of pseudo-exfoliation syndrome and associated factors in Gondar university comprehensive specialized hospital tertiary eye care and training center.

Methods and materials: Institution-based cross-sectional study was conducted from January to March 2019 at Gondar university comprehensive specialized hospital tertiary eye care and training center among 295 patients. Consecutive 295 participants aged above 40 years were involved in the study. A structured questionnaire and ocular examination were used to collect the data. Data were entered into EPI-INFO 3.5.1 and exported to SPSS version 20 for analysis. Factors associated with pseudoexfoliation syndrome were ascertained by chi-square and independent t-test. Statistical significance was considered when p-value <0.05.

Results: A total of 295 adults participated in the study with a response rate of 92.8%. The median (±IQR) age of study respondents was 64(±9) years and 67.8% were males. The proportion pseudoexfoliation syndrome was 34.6% [95% CI: 29.2-40.7%]. The mean IOP and mean age were significantly higher among patients with pseudoexfoliation syndrome. Age, sex, high IOP, glaucoma, outdoor work, and rural residence were significantly associated with the proportion of pseudoexfoliation syndrome.

Conclusion: The proportion of pseudoexfoliation syndrome among participants aged ≥40 years was high. Age, sex, high IOP, glaucoma, outdoor work, and rural residence were factors having a significant association with the proportion of pseudoexfoliation syndrome.

Purpose: To investigate the effect of a single application of cationic emulsion in controlling tear film evaporation and improving tear quality and quantity.

Materials a methods: Twenty male subjects diagnosed with DE were enrolled in the study with an average age of 45.8 ± 6.37 years. The tear film parameters were observed at several time points post-instillation of the cationic emulsion (10, 20, 30, and 60 min). The tear evaporation rate (TER) was measured with a VapoMeter. Noninvasive tear break-up time and meniscus height were assessed using OCULUS Keratograph.

Results: TER decreased by more than 20% at 20, 30, and 60 minutes time points after instillation of single drop of cationic emulsion. Also, a significant improvement in tear film stability was found at all time points following the instillation of cationic emulsion eye drops. The mean tear break-up time increased from 5.55 ± 2.87 to 6.6 ± 4.2 sec at 60 minutes. The maximum increase in tear break-up time occurred at 30 minutes time point. The TMH was also significantly higher post-instillation of oil emulsion eye drops. There was a significant increase in the TMH post-therapy with oil drop at all time points.

Conclusion: The overall study findings of this study illustrate that the single application of a cationic emulsion effectively controls tear film evaporation in patients with mild to moderate DEs. The cationic emulsion efficiently enhanced both the tear film stability and the tear meniscus volume.