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PloS One 2024Uncorrected refractive errors pose a significant challenge globally, particularly in remote regions of low-middle income countries where access to optometric care is...
INTRODUCTION
Uncorrected refractive errors pose a significant challenge globally, particularly in remote regions of low-middle income countries where access to optometric care is often limited. Telerefraction, which involves refraction by a trained technician followed by real-time consultation with remote optometrist, is a promising approach for such remote settings. This study aimed to evaluate the accuracy of this model.
METHODS
This prospective study, conducted in New Delhi, compared tele-refraction to in-person examinations. Trained technicians used a simple device, Click-check, to perform objective refraction and a tele-refraction platform to enter the findings of objective refraction. Final prescription was made after consulting a remote optometrist on that platform. Masked face-to-face optometrists served as the gold standard. The study involved refraction in 222 patients and 428 eyes.
RESULTS
Tele-refraction demonstrated a strong agreement with in-person optometry, achieving 84.6% in spherical correction and 81% conformity in spherical equivalent. The mean difference of spherical equivalent between the two arms was only 0.11 D. The consultation with a remote optometrist improved conformity of spherical equivalent by 14.8% over objective refraction. 82 percent eyes matched in best corrected visual acuity and 92 percent were within 0.1 logMAR difference. For cylindrical axis, 74% eye were within acceptable 10 degrees of difference. The mismatch amongst the individual trained technicians, in terms of difference between the tele-refraction arm and the face-to face optometrist arm was found to be significant for cylindrical axis and not for spherical power and spherical equivalent.
CONCLUSION
Our study found tele-refraction by a trained technician comparable to refraction done by face-to-face optometrist. Tele-refraction, coupled with remote optometrist guidance can address the optometry resource gap in underserved areas. Thus, this model offers a transformative approach to enhancing the accessibility and quality of eye care services, which can significantly contribute to our efforts in achieving the global targets set by the World Health Organization for effective refractive error coverage. More standardized training for these technicians on ClickCheckTM for detecting the cylindrical axis with better accuracy, can improve this model further.
Topics: Humans; Refractive Errors; Adult; Female; Male; Prospective Studies; Remote Consultation; Optometrists; Middle Aged; Reproducibility of Results; Optometry; Telemedicine; Young Adult; Adolescent; Refraction, Ocular; Visual Acuity; Aged
PubMed: 38913708
DOI: 10.1371/journal.pone.0299491 -
Translational Vision Science &... Jun 2024To assess longitudinal reproducibility of metrics of foveal density (peak cone density [PCD], cone density centroid [CDC], and 80th percentile centroid area) in...
PURPOSE
To assess longitudinal reproducibility of metrics of foveal density (peak cone density [PCD], cone density centroid [CDC], and 80th percentile centroid area) in participants with normal vision.
METHODS
Participants (n = 19; five male and 14 female) were imaged at two time points (average interval of 3.2 years) using an adaptive optics scanning light ophthalmoscope (AOSLO). Foveally centered regions of interest (ROIs) were extracted from AOSLO montages. Cone coordinate matrices were semiautomatically derived for each ROI, and cone mosaic metrics were calculated.
RESULTS
On average, there were no significant changes in cone mosaic metrics between visits. The average ± SD PCD was 187,000 ± 20,000 cones/mm2 and 189,000 ± 21,700 cones/mm2 for visits 1 and 2, respectively (P = 0.52). The average ± SD density at the CDC was 183,000 ± 19,000 cones/mm2 and 184,000 ± 20,800 cones/mm2 for visits 1 and 2, respectively (P = 0.78). The average ± SD 80th percentile isodensity contour area was 15,400 ± 1800 µm2 and 15,600 ± 1910 µm2 for visits 1 and 2, respectively (P = 0.57).
CONCLUSIONS
Foveal cone mosaic density metrics were highly reproducible in the cohort examined here, although further study is required in more diverse populations.
TRANSLATIONAL RELEVANCE
Determination of the normative longitudinal changes in foveal cone topography is key for evaluating longitudinal measures of foveal cone topography in patients with progressive retinal dystrophies.
Topics: Humans; Retinal Cone Photoreceptor Cells; Male; Fovea Centralis; Female; Adult; Reproducibility of Results; Middle Aged; Cell Count; Young Adult; Ophthalmoscopy; Tomography, Optical Coherence; Visual Acuity
PubMed: 38913007
DOI: 10.1167/tvst.13.6.18 -
Vision Research Jun 2024Short-term monocular deprivation in normally sighted adult humans produces a transient shift of ocular dominance, boosting the deprived eye. This effect has been...
Short-term monocular deprivation in normally sighted adult humans produces a transient shift of ocular dominance, boosting the deprived eye. This effect has been documented with both perceptual tests and through physiological recordings, but no previous study simultaneously measured physiological responses and the perceptual effects of deprivation. Here we propose an integrated experimental paradigm that combines binocular rivalry with pupillometry, to introduce an objective physiological index of ocular dominance plasticity, acquired concurrently with perceptual testing. Ten participants reported the perceptual dynamics of binocular rivalry, while we measured pupil diameter. Stimuli were a white and a black disk, each presented monocularly. Rivalry dynamics and pupil-size traces were compared before and after 2 h of monocular deprivation, achieved by applying a translucent patch over the dominant eye. Consistent with prior research, we observed that monocular deprivation boosts the deprived-eye signal and consequently increases ocular dominance. In line with previous studies, we also observed subtle but systematic modulations of pupil size that tracked alternations between exclusive dominance phases of the black or white disk. Following monocular deprivation, the amplitude of these pupil-size modulations increased, which is consistent with the post-deprivation boost of the deprived eye and the increase of ocular dominance. This provides evidence that deprivation impacts the effective strength of monocular visual stimuli, coherently affecting perceptual reports and the automatic and unconscious regulation of pupil diameter. Our results show that a combined paradigm of binocular rivalry and pupillometry gives new insights into the physiological mechanisms underlying deprivation effects.
PubMed: 38909478
DOI: 10.1016/j.visres.2024.108449 -
Acta Psychologica Jun 2024Empirical evidence in support of a shared system for non-symbolic and symbolic number processing has been inconclusive. The current study aims to address this question...
Empirical evidence in support of a shared system for non-symbolic and symbolic number processing has been inconclusive. The current study aims to address this question in a novel way, specifically by testing whether the efficient coding principle based on co-occurrence of number symbols in natural language holds for both non-symbolic and symbolic number processing. The efficient coding principle postulates that perception is optimized when stimuli frequently co-occur in a natural environment. We hypothesized that both numerical ratios and co-occurrence frequencies of symbolic numbers would significantly influence participants' performance on a non-symbolic and symbolic number comparison task. To test this hypothesis, we employed latent semantic analysis on a TASA corpus to quantify number co-occurrence in natural language and calculate language similarity estimates. We engaged 73 native English speakers (mean age = 19.36, standard deviation = 1.83) with normal or corrected vision and no learning disorders in a number comparison task involving non-symbolic (dot arrays) and symbolic stimuli (Arabic numerals and English number words). Results showed that numerical ratios significantly predicted participants' performances across all number formats (ps < 0.001). Language similarity estimates derived from everyday language also predicted performance on the non-symbolic task and the symbolic task involving number words (ps < 0.007). Our results highlight the complex nature of numerical processing, pointing to the co-occurrence of number symbols in natural language as an auxiliary factor in understanding the shared characteristics between non-symbolic and symbolic number representations. Given that our study focused on a limited number range (5 to 16) and a specific task type, future studies should explore a wider range of tasks and numbers to further test the role of the efficient coding principle in number processing.
PubMed: 38908226
DOI: 10.1016/j.actpsy.2024.104374 -
BMC Ophthalmology Jun 2024This study aims to investigate relative peripheral refractive (RPR) characteristics in children with non-amblyopic myopic anisometropia and explore potential...
BACKGROUND
This study aims to investigate relative peripheral refractive (RPR) characteristics in children with non-amblyopic myopic anisometropia and explore potential associations between relative peripheral refractive errors (RPRE) and myopia.
METHODS
Relative peripheral refractive errors were assessed in 64 children diagnosed with non-amblyopic myopic anisometropia utilizing multispectral refraction topography (MRT). Two eyes of each patient were divided into into the more myopia eyes group (ME) and the fellow eyes group (FE). Evaluated parameters encompassed total defocus values (TRDV), defocus values at eccentricities spanning 0 to 15 degrees (RDV-15), 0 to 30 degrees (RDV-30), 0 to 45 degrees (RDV-45), as well as superior (RDV-S), inferior (RDV-I), temporal (RDV-T), and nasal (RDV-N) positions.
RESULTS
The study revealed a noteworthy contrast in TRDV values between Group ME (0.52 ± 0.36) and Group FE (0.17 ± 0.41), with a substantial significance (P < 0.0001). While no significant RDV-15 difference emerged between Group ME (0.01 ± 0.05) and Group FE (-0.01 ± 0.07) (P > 0.05), a meaningful RDV-30 difference existed between Group ME (0.11 ± 0.14) and Group FE (0.03 ± 0.19) (P = 0.0017). A significant discrepancy in RDV-45 was also observed between Group ME (0.39 ± 0.29) and Group FE (0.13 ± 0.34) (P < 0.001). Notably, RDV-I and RDV-T positions demonstrated marked differences between Group ME and Group FE (P < 0.0001), whereas no significant disparity was noted in RDV-S and RDV-N positions (P > 0.05).
CONCLUSION
Eyes exhibiting greater myopia manifested more hyperopic peripheral defocus in the context of anisometropia. MRT as a novel ophthalmic evaluation technique, holds promising potential for broader clinical applications in the future.
Topics: Humans; Anisometropia; Male; Female; Myopia; Child; Refraction, Ocular; Visual Acuity; Corneal Topography; Adolescent; Child, Preschool
PubMed: 38907184
DOI: 10.1186/s12886-024-03527-1 -
Foot (Edinburgh, Scotland) Jun 2024This randomised crossover study with repeated measures examined the influence of the three most common foot starting positions used in conducting the calf raise test...
BACKGROUND
This randomised crossover study with repeated measures examined the influence of the three most common foot starting positions used in conducting the calf raise test (CRT) on test outcomes. This study also accounted for the potential influence of gender, age, body mass index (BMI), and level of physical activity on test outcomes.
METHODS
Forty-nine healthy individuals (59 % female, 21 ± 4 years) performed single-leg calf raise repetitions in a human movement laboratory in three randomised foot starting positions: flat, 10° incline, and step. The validated Calf Raise application was used to track the vertical displacement of a marker placed on the foot using computer vision. The application extracted the following CRT outcomes from the vertical displacement curve: number of repetitions, peak vertical height, total vertical displacement, and total positive work. Data were analysed using mixed-effects models and stepwise regression.
RESULTS
There was a significant main effect (P < 0.001) of foot starting position on all outcomes, with all paired comparisons being statistically significant (P ≤ 0.023). Repetitions, total vertical displacement, and total positive work were greatest in flat and lowest in step, whereas peak vertical height was greatest in incline and lowest in step. Gender (P = 0.021; males>females) and BMI (P = 0.002; lower BMI>higher BMI) significantly influenced the number of repetitions. Gender (P < 0.001; males>females) also influenced total positive work. Age and physical activity levels did not significantly influence CRT outcomes.
CONCLUSIONS
CRT foot starting position mattered and significantly affected all CRT outcomes. CRT foot starting position needs consideration when contrasting data in research and practice.
PubMed: 38905944
DOI: 10.1016/j.foot.2024.102112 -
Indian Journal of Ophthalmology Jul 2024Traboulsi syndrome is a sporadic autosomal recessive disorder. Very few cases reported and no surgical treatment has been described.
BACKGROUND
Traboulsi syndrome is a sporadic autosomal recessive disorder. Very few cases reported and no surgical treatment has been described.
PURPOSE
The purpose of the study was to describe the surgical treatment of a case of Traboulsi syndrome with intercalary staphyloma.
SYNOPSIS
Traboulsi syndrome[1-3] is a type of spontaneous filtering bleb. The case was of a 31-year-old lady with a flat anterior chamber and large intercalary staphyloma, with a subluxated clear lens. Liberal peritomy was done. The staphyloma was cut and the displaced lens was delivered through it. It was closed with 7-0 vicryl continuous suture. A cross-linked cornea was used after removing the Descemet membrane. It was modified to match the crescentic shape of the limbus by using 11 and 6 mm trephine. Two wedge-shaped defects were created and tissue was excised between them, which were then sutured to increase the arc radius. A peripheral flange at the corneal edge was created. A pocket was created in the host cornea to accommodate the donor corneal flange. The donor cornea was tucked in and the graft was sutured. The sclera was used to suture another side prophylactically, making a 360-degree encirclage. The patient got ambulatory vision postsurgery. The use of the cornea as biological encirclage has not been described previously.
HIGHLIGHTS
Using a cross-linked cornea. Creating wedge-shaped defects in crescentic corneal graft to increase arc radius. Use of cornea as encirclage.Link of video:https://youtu.be/T3b5rkvFmlc.
Topics: Humans; Adult; Female; Visual Acuity; Anterior Chamber; Syndrome; Lens Subluxation; Ophthalmologic Surgical Procedures; Suture Techniques; Intraocular Pressure
PubMed: 38905471
DOI: 10.4103/IJO.IJO_1968_23 -
Indian Journal of Ophthalmology Jul 2024
Topics: Humans; Ethambutol; Antitubercular Agents; Male; Female; Adult; Electroretinography; Middle Aged; Visual Acuity; Tomography, Optical Coherence
PubMed: 38905470
DOI: 10.4103/IJO.IJO_494_23 -
Indian Journal of Ophthalmology Jul 2024The aim of this study is to describe a modified technique for internal refixation of dislocated scleral-sutured polymethylmethacrylate (PMMA) intraocular lenses (IOLs)...
The aim of this study is to describe a modified technique for internal refixation of dislocated scleral-sutured polymethylmethacrylate (PMMA) intraocular lenses (IOLs) with eyelets. Three-port pars plana vitrectomy was performed. Through the scleral fixation site, a 30-gauge needle loaded with an 8-0 polypropylene suture was inserted into the vitreous cavity. The suture end was passed through the eyelet of IOL with 25-gauge forceps. Next, it was guided out of the eye through the original scleral fixation point. The end of the exterior suture was buried with a flapless intrascleral knotting technique. Six eyes of six patients were successfully treated with this technique and followed up for 6-12 months postsurgery. In all cases, there was significant improvement in uncorrected visual acuity. IOLs were stable with proper centration and no major complications. This modified technique offers an effective and minimally invasive surgical alternative for refixation of dislocated scleral-sutured PMMA IOLs with eyelets.
Topics: Humans; Polymethyl Methacrylate; Male; Visual Acuity; Lenses, Intraocular; Female; Reoperation; Suture Techniques; Vitrectomy; Middle Aged; Sclera; Artificial Lens Implant Migration; Follow-Up Studies; Aged; Sutures; Adult
PubMed: 38905465
DOI: 10.4103/IJO.IJO_2809_23 -
Indian Journal of Ophthalmology Jul 2024To report the preliminary experience and initial clinical results following SMILE for the treatment of mixed astigmatism.
PURPOSE
To report the preliminary experience and initial clinical results following SMILE for the treatment of mixed astigmatism.
METHODS
Thirteen eyes of nine patients with a mean age of 27 ± 4.36 years were included in the series. In 8/13 eyes, myopic SMILE license and in 4/13 eyes, hyperopic SMILE license (available as part of an open/research software) was used for the treatment. The mean follow-up was 9.5 ± 8.7 (0.5-24) months, and the median follow-up was 6 months.
SETTING
Nethradhama Superspeciality Eye Hospital, Bangalore, India.
DESIGN
Exploratory study.
RESULTS
The mean preoperative sphere, cylinder, and spherical equivalent (SE) were 1.44 ± 1.63, -2.70 ± 2.30, and -0.24 ± 1.14 D, which changed to -0.03 ± 0.30, -0.28 ± 0.48, and -0.18 ± 0.49 D, respectively, 6 months postoperatively. Furthermore, 85% (11/13) eyes were within ± 0.50 D, 92% (12/13) eyes were within ± 1.00 D, while all eyes were within ± 1.50 D of SE correction. All eyes were within ± 1.00 D of cylinder correction. In addition, 92% (12/13) eyes had UDVA better than 20/32, with 54% (7/13) eyes having UDVA 20/20 or better. Safety and efficacy indices were 1.08 and 0.92, respectively. No eyes lost more than 1 line of CDVA. The mean corneal higher order aberrations (HOA) increased from 0.111 ± 0.048 to 0.209 ± 0.056 (P < 0.001). The mean objective scatter index (OSI) did not show a significant change (pre = 0.71 ± 0.69, 6 months = 0.89 ± 0.20; P = 0.35).
CONCLUSION
Early experience showed that SMILE was feasible for the management of eyes with mixed astigmatism, without any intraoperative complications, unique to the procedure.
Topics: Humans; Astigmatism; Male; Adult; Female; Visual Acuity; Feasibility Studies; Refraction, Ocular; Corneal Surgery, Laser; Follow-Up Studies; Young Adult; Corneal Topography; Corneal Stroma; Software; Lasers, Excimer; Treatment Outcome; Retrospective Studies; Myopia; Microsurgery
PubMed: 38905464
DOI: 10.4103/IJO.IJO_1273_23