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Low-grade Glioma Presenting in the Optic Pathways and Hypothalamus
Published in David A. Walker, Giorgio Perilongo, Roger E. Taylor, Ian F. Pollack, Brain and Spinal Tumors of Childhood, 2020
Peter M.K. de Blank, Ian Simmons, Astrid Sehested, Michael J. Fisher
Because gradations in typical acuity tests are not uniform, many researchers convert Snellen acuity (such as 20/20) to a linear scale, such as the logarithm of the minimal angle of resolution (logMAR = base 10 logarithm of [1/Snellen decimal equivalent]). For example, if the Snellen visual acuity is 20/25, the decimal equivalent is 20 divided by 25 = 0.8, and therefore the logMAR equivalent of 20/25 is log10(1/0.8) = 0.1 (Table 10.2). While logMAR is less intuitive than Snellen readings, the change in logMAR vision is more meaningful.
The Implementation of Primary Orthoptic Screening For 4–5yr old Children in Inner City Bradford
Published in Jan-Tjeerd de Faber, 28th European Strabismological Association Meeting, 2020
The initial audit of the service helped refine our pass/fail criteria especially the Welch-Allyn results. A LogMAR test is now used in place of the Sonksen-Silver visual acuity test. The uptake was excellent (93%) since we had a captive audience in school. The incidence of squint mirrors normal rates quoted in the literature (Oliver & Nawratzki 1971) but the referral rate of refractive error is significantly above what we expected. This may well be due to the ethnic make-up of the cohort screened which is predominantly Asian (Bradford Council 1991–2001). Bradford’s population is 25% Pakistani and inner city Bradford may well be higher than this.
Posterior juxtascleral delivery of anecortave acetate for treatment of age-related macular degeneration
Published in A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha, Vitreoretinal Surgical Techniques, 2019
This placebo-controlled randomized clinical safety and efficacy study was conducted to determine the safety and efficacy of anecortave acetate for depot suspension (3, 15, or 30 mg) versus placebo (vehicle administration) for inhibition of growth of neovascular subfoveal ARMD lesions. Anecortave acetate was administered as a 0.5 ml posterior juxtascleral depot on bare sclera in the region of the macula using the cannula and procedure described above. Patients with predominantly classic or minimally classic subfoveal CNV were enrolled; 128 eyes of 128 patients were enrolled and randomized 1 : 1 : 1 : 1 to posterior juxtascleral administration of anecortave acetate or placebo in masked fashion. The primary outcome measure was mean change from baseline in best-corrected logMAR (log of minimum angle of resolution) vision at month 12, with 12 months of additional follow-up. Assessments of clinically relevant changes in logMAR vision and lesion characteristics were also compared. Detailed ophthalmic examinations were conducted, including best-corrected logMAR visual acuity, external examination of the eye, measurement of extraocular motility, pupil responsiveness, slit-lamp examination of the anterior segment and lens, dilated fundus examination, and measurement of intraocular pressure (IOP).
Augmentation of telemedicine post-operative follow-up after oculofacial plastic surgery with a self-guided patient tool
Published in Orbit, 2023
Davin C. Ashraf, Amanda Miller, Meleha Ahmad, Loreley D. Smith, Seanna R. Grob, Bryan J. Winn, Robert C. Kersten, M. Reza Vagefi
Data analysis was performed using R (R Core Team, 2022). Means were compared with the t-test for unpaired data, and the paired t-test for intrasubject data. The Krippendorff alpha was calculated to evaluate inter-rater reliability for photograph quality.11 The pROC R package was used to generate a receiver operating characteristic (ROC) curve for photograph blur analysis.12 Multiple logistic regression was used to explore predictive factors for multimedia quality and patient-reported outcomes. Vision was converted to logarithm of the minimum angle of resolution (logMAR) notation for the purposes of analysis. In order to compare paper- versus smartphone application-based visual acuity measurement, the difference between the tool and clinic visual acuity measurements were first calculated for each patient. The mean of the differences for patients using the smartphone application and those using the paper chart were then compared with a t-test. A P-value of <0.05 was considered significant.
Delayed Diagnosis of Amblyopia in Children of Lower Socioeconomic Families: The Hong Kong Children Eye Study
Published in Ophthalmic Epidemiology, 2022
Xiu Juan Zhang, Posey Po-Yin Wong, Emily S Wong, Ka Wai Kam, Benjamin Hon Kei Yip, Yuzhou Zhang, Wei Zhang, Alvin L. Young, Li Jia Chen, Patrick Ip, Clement C. Tham, Chi Pui Pang, Jason C. Yam
Visual acuity was measured with (aided VA) or without spectacles (unaided VA) using a logarithm of the minimum angle of resolution (LogMAR) chart (Nidek, Gamagori, Japan). The chart was retro-illuminated with a total of 70 letters, five letters to a line. Each child was examined monocularly at 5 meters, with the right eye followed by the left eye. LogMAR scores ranged from 1.0 (20/200 Snellen equivalent) to −0.3 (20/10 Snellen equivalent). If neither the unaided nor aided visual acuity reached 0.1 (20/25 Snellen equivalent), best-corrected visual acuity (BCVA) was subsequently measured. Subjective refraction was performed by a trained optometrist for all children having visual acuity scores greater than 0.1 in either eye using a trial frame placed and adjusted on the participants’ faces. The visual acuity obtained was defined as the BCVA.
Falls and Physical Activity among Cataract Patients in Vietnam
Published in Ophthalmic Epidemiology, 2022
Quyen To, Van-Anh Huynh, Dung Do, Vu Do, Nathan Congdon, Lynn Meuleners, Corneel Vandelanotte, Hiep Hong, Ho Nguyen, Kien To
Demographic characteristics including age, gender, education level, marital status and monthly income were self-reported. Highest education level was grouped into “grade 5 or below (elementary/below)”, “grade 6 to 9 (middle school)”, and “above grade 9 (high school/above)”. Monthly income was categorized as “low” if <4 million VND (<US$175), “medium” if 4 – <10 million VND (US$175-<435), or “high” if ≥10 million VND (≥US$435). Monocular and binocular visual acuity were measured using a Snellen chart at a distance of 5 m or equivalence. Participants were asked to wear their corrective lenses if available and read letters on the chart in a well-lit indoor area.31 Logarithm of the Minimum Angle of Resolution (logMAR) values were calculated based on Snellen equivalent. If the largest letters on the chart (corresponding to 20/200 or logMAR 1.0 vision) could not be seen, logMAR values were calculated using the position at which the patient could count fingers (for example, a distance of 0.5 m is equivalent to a logMAR value of 2.0).32 A higher logMAR score represents worse vision. Monocular and binocular contrast sensitivity with current spectacle correction if available were measured using a Pelli-Robson chart33 calibrated at 1 m in a standard examination room in the hospital eye clinic, and expressed in log units. A higher score represents better contrast sensitivity.