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Pakistan Journal of Medical Sciences 2023To evaluate the feasibility of a novel and simple smart phone-based Retinopathy of Prematurity (ROP) screening approach in a resource-constrained setting.
OBJECTIVES
To evaluate the feasibility of a novel and simple smart phone-based Retinopathy of Prematurity (ROP) screening approach in a resource-constrained setting.
METHODS
This cross-sectional validation study was conducted at the Department of Ophthalmology and Neonatal Intensive Care Unit (NICU) of The Aga Khan University Hospital, Pakistan, from January 2022 to April 2022. A total of 63 images of eyes with active ROP (stage-1, 2, 3, 4 and/or plus or pre-plus disease) were included in this study. The stage of ROP was documented by the principal investigator using an indirect ophthalmoscope and retinal images were obtained using this novel technique. These images were shared with two masked ROP experts who rated the image quality and determined the stage of ROP and presence of plus disease. Their reports were compared with the initial findings reported by principal investigator using indirect ophthalmoscope.
RESULTS
We reviewed 63 images for image quality, stage of ROP and presence of plus disease. There was significant agreement between the gold standard and the Rater-1 and 2 for the presence of plus disease (Cohen's kappa was 0.84 and 1.0) and the stage of the disease (Cohen's kappa 0.65 and 1.0). There was significant agreement between the Rater for presence of plus disease and any stage of ROP (Cohen's κ: 0.84 and 0.65 for plus disease and any stage of the ROP, respectively). Rater-1 and 2 rated 96.83% and 98.41% images as excellent / acceptable respectively.
CONCLUSIONS
High quality retinal images can be captured with a smartphone and 28D lens without using any additional adapter equipment. This approach of ROP screening can form basis of telemedicine for ROP in resource constrained areas.
PubMed: 37250571
DOI: 10.12669/pjms.39.3.7053 -
Frontiers in Neuroscience 2022Diabetic retinopathy (DR) is one of the major complications of diabetic eye diseases, causing vision loss and blindness worldwide. The concept of diabetic retinopathy...
Diabetic retinopathy (DR) is one of the major complications of diabetic eye diseases, causing vision loss and blindness worldwide. The concept of diabetic retinopathy has evolved from microvascular disease into more complex neurovascular disorders. Early in the disease progression of diabetes, the neuronal and glial cells are compromised before any microvascular abnormalities clinically detected by the ophthalmoscopic examination. This implies understanding the pathophysiological mechanisms at the early stage of disease progression especially due to diabetes-induced metabolic alterations to damage the neural retina so that early intervention and treatments options can be identified to prevent and inhibit the progression of DR. Hyperglycemia has been widely considered the major contributor to the progression of the retinal damage, even though tight control of glucose does not seem to have a bigger effect on the incidence or progression of retinal damage that leads to DR. Emerging evidence suggests that besides diabetes-induced hyperglycemia, dyslipidemia and amino acid defects might be a major contributor to the progression of early neurovascular retinal damage. In this review, we have discussed recent advances in the alterations of key metabolites of carbohydrate, lipid, and amino acids and their implications for neurovascular damage in DR.
PubMed: 35911994
DOI: 10.3389/fnins.2022.938029 -
Eye (London, England) Mar 2021To compare skill acquisition of the new, cost-effective Arclight ophthalmoscope, with the traditional ophthalmoscope (TO), in medical students with no prior experience...
BACKGROUND/OBJECTIVES
To compare skill acquisition of the new, cost-effective Arclight ophthalmoscope, with the traditional ophthalmoscope (TO), in medical students with no prior experience of ophthalmoscopy.
SUBJECTS/METHODS
University of Dundee medical students took part in a cross-over trial. Students were divided into two groups and were alternately taught each device using a video tutorial. In period one, Group A was taught the TO first; Group B was taught the Arclight. They were then assessed using simulated objective, structured, clinical, examinations, examining four model heads with lettered fundal photographs of varying sizes of font. Groups crossed over following a 2-week washout period and were taught the second device and reassessed. A questionnaire was distributed to ascertain students' opinions and preferences.
RESULTS
Forty medical students participated. Overall, 92.5% of students performed better with the Arclight, irrespective of cross-over trial period. The mean difference in score in period one of the cross-over trial was 16.77 (95% CI: 11.63-21.93), with students performing better with the Arclight (p < 0.0001). The mean difference in score in period two was 8.02 (95% CI: 4.52-11.52), with students performing better with the Arclight (p < 0.0001). In addition, performance with the TO improved by 52.9% following initial exposure to the Arclight. The Arclight was the preferred device by 82.5% of students, and 82.5% of students would choose this device for future practice.
CONCLUSION
Students performed better with and preferred the Arclight ophthalmoscope. The Arclight could be considered as a suitable alternative to the TO used for training medical students.
Topics: Clinical Competence; Cross-Over Studies; Education, Medical, Undergraduate; Humans; Ophthalmoscopy; Students, Medical
PubMed: 32461568
DOI: 10.1038/s41433-020-0972-3 -
Biomedical Optics Express Oct 2022Fluorescence lifetime imaging ophthalmoscopy (FLIO), a technique for investigating metabolic changes in the eye ground, can reveal the first signs of diseases related to... (Review)
Review
Fluorescence lifetime imaging ophthalmoscopy (FLIO), a technique for investigating metabolic changes in the eye ground, can reveal the first signs of diseases related to metabolism. The fluorescence of the natural lens overlies the fundus fluorescence. Although the influence of natural lens fluorescence can be somewhat decreased with mathematical models, excluding this influence during the measurement by using hardware enables more exact estimation of the fundus fluorescence. Here, we analyze four 1-photon excitation hardware solutions to suppress the influence of natural lens fluorescence: aperture stop separation, confocal scanning laser ophthalmoscopy, combined confocal scanning laser ophthalmoscopy and aperture stop separation, and dual point confocal scanning laser ophthalmoscopy. The effect of each principle is demonstrated in examples. The best suppression is provided by the dual point principle, realized with a confocal scanning laser ophthalmoscope. In this case, in addition to the fluorescence of the whole eye, the fluorescence of the anterior part of the eye is detected from a non-excited spot of the fundus. The intensity and time-resolved fluorescence spectral data of the fundus are derived through the subtraction of the simultaneously measured fluorescence of the excited and non-excited spots. Advantages of future 2-photon fluorescence excitation are also discussed. This study provides the first quantitative evaluation of hardware principles to suppress the fluorescence of the natural lens during measurements of fundus autofluorescence.
PubMed: 36425615
DOI: 10.1364/BOE.462559 -
Photonics Research Jul 2022To assess the performance of adaptive optics and predict an optimal wavefront correction, we built a wavefront reconstructor with a damped transpose matrix of the...
To assess the performance of adaptive optics and predict an optimal wavefront correction, we built a wavefront reconstructor with a damped transpose matrix of the influence function. Using an integral control strategy, we tested this reconstructor with four deformable mirrors in an experimental system, an adaptive optics scanning laser ophthalmoscope, and an adaptive optics near-confocal ophthalmoscope. Testing results proved that this reconstructor could ensure a stable and precise correction for wavefront aberration compared to a conventional optimal reconstructor formed by the inverse matrix of the influence function. This method may provide a helpful tool for testing, evaluating, and optimizing adaptive optics systems.
PubMed: 37153536
DOI: 10.1364/prj.452364 -
Indian Journal of Ophthalmology Jun 2022Comparison of patient satisfaction with red-free (green) versus yellow light using binocular indirect ophthalmoscope for retinal examination. (Observational Study)
Observational Study Randomized Controlled Trial
PURPOSE
Comparison of patient satisfaction with red-free (green) versus yellow light using binocular indirect ophthalmoscope for retinal examination.
METHODS
This is an observational questionnaire-based study of 100 myopes in the age group of 18-40 years coming for a routine check-up or for refractive surgery workup. The examination was done using an indirect ophthalmoscope and a 20D lens with green or yellow light and was assigned in two groups randomly using the coin toss method, following which, a questionnaire was used to assess the following parameters: a) level of comfort, b) any complaints of discomfort during examination, d) preference of the used light source in future, e) grading of discomfort on a linear scale, and f) patient cooperation and duration of examination.
RESULTS
Patients were randomized for observation with IDO using either green light (n = 55) or yellow light (n = 45) filter. In the study, 46 patients (83.6%) were very comfortable and only 9 patients (16.4%) experienced mild discomfort when using red-free (green) light, while only 3 patients (6.7%) were very comfortable and 31 (68.9%) had mild discomfort when using yellow light. The complaints of watering with yellow and green light were noted in 36 patients (80.0%) and 15 patients (27.3%), pain in 13 patients (28.9%) and 3 patients (5.5%), light sensitivity in 29 patients (64.4%) and 4 patients (7.3%), respectively, all being significantly more in yellow light category (P < 0.001). The time of examination was significantly more in yellow light category with 83 ± 10.75 seconds (P < 0.001).
CONCLUSION
Retinal examination using the green filter of indirect ophthalmoscope is more comfortable in examining the patients as compared to routine yellow light with decreased number of complaints, lesser examination time, and better patient cooperation.
Topics: Adolescent; Adult; Humans; Ophthalmology; Ophthalmoscopes; Patient Satisfaction; Physical Examination; Young Adult
PubMed: 35647977
DOI: 10.4103/ijo.IJO_3079_21 -
Journal of Vision Mar 2021When the scotoma is binocular in macular degeneration (MD), it often obscures objects of interest, causing individuals to miss information. To map the binocular scotoma...
When the scotoma is binocular in macular degeneration (MD), it often obscures objects of interest, causing individuals to miss information. To map the binocular scotoma as precisely as current methods that map the monocular scotoma, we propose an iterative eye-tracker method. Study participants included nine individuals with MD and four age-matched controls. We measured the extent of the monocular scotomata using a scanning laser ophthalmoscope/optical coherence tomography (SLO/OCT). Then, we precisely mapped monocular and binocular scotomata with an eye tracker, while fixation was monitored. Participants responded whenever they detected briefly flashed dots, which were first presented on a coarse grid, and then at manually selected points to refine the shape and edges of the scotoma. Monocular scotomata measured in the SLO and eye tracker are highly similar, validating the eye-tracking method for scotoma mapping. Moreover, all participants used clustered fixation loci corresponding to their dominant preferred fixation locus. Critically, for individuals with binocular scotomata, the binocular map from the eye tracker was consistent with the overlap of the monocular scotoma profiles from the SLO. Thus, eye-tracker-based perimetry offers a reliable and sensitive tool for measuring both monocular and binocular scotomata, unlike the SLO/OCT that is limited to monocular viewing.
Topics: Aged; Case-Control Studies; Female; Humans; Macular Degeneration; Male; Middle Aged; Ophthalmoscopes; Scotoma; Tomography, Optical Coherence; Vision, Binocular; Visual Field Tests
PubMed: 33666643
DOI: 10.1167/jov.21.3.9 -
Journal of Academic Ophthalmology (2017) Jul 2021The aim of the study is to compare performance and ease-of-use (EOU) of optic disk assessment using a smartphone direct ophthalmoscope attachment (D-EYE) to the gold...
The aim of the study is to compare performance and ease-of-use (EOU) of optic disk assessment using a smartphone direct ophthalmoscope attachment (D-EYE) to the gold standard direct ophthalmoscope (DO). The type of study involved is prospective, randomized, crossover, and educational trial. The participants involved were first year medical students inexperienced in ophthalmoscopy. Optic disks of standardized and volunteer patients were examined using the D-EYE and a conventional DO. Optic disk identification, EOU ratings of the devices, self-reported confidence level in their examination with the devices, and estimation of vertical cup-to-disk ratio (VCDR) were compared. Analyses included Chi-square tests, independent samples -tests, correlations, and multivariable linear regression. Forty-four medical students voluntarily participated in the study. Students using the DO required more attempts (3.57 vs. 2.69, = 0.010) and time (197.00 vs. 168.02 seconds, = 0.043) to match the patient's fundus to the correct photograph. Overall EOU between the devices (6.40 vs. 4.79, < 0.001) and overall confidence in examination (5.65 vs. 4.49, = 0.003) were greater when using the D-EYE. There were no statistically significant differences in accuracy of VCDR estimations between the two ophthalmoscopes. Smartphone ophthalmoscopy could offer additional learning opportunities in medical education and may be considered in clinical practice by non-specialist physicians given its greater EOU and increased success in visualizing the optic disk.
PubMed: 37388835
DOI: 10.1055/s-0041-1736438 -
Frontiers in Cellular and Infection... 2021Slit lamps are routinely used to examine large numbers of patients every day due to high throughput. Previous, cultivation-based results suggested slit lamps to be...
Slit lamps are routinely used to examine large numbers of patients every day due to high throughput. Previous, cultivation-based results suggested slit lamps to be contaminated with bacteria, mostly coagulase-negative staphylococci, followed by micrococci, bacilli, but also . Our study aimed at obtaining a much more comprehensive, cultivation-independent view of the slit lamp bacteriota and its hygienic relevance, as regularly touched surfaces usually represent fomites, particularly if used by different persons. We performed extensive 16S rRNA gene sequencing to analyse the bacteriota, of 46 slit lamps from two tertiary care centers at two sampling sites, respectively. 82 samples yielded enough sequences for downstream analyses and revealed contamination with bacteria of mostly human skin, mucosa and probably eye origin, predominantly cutibacteria, staphylococci and corynebacteria. The taxonomic assignment of 3369 ASVs (amplicon sequence variants) revealed 19 bacterial phyla and 468 genera across all samples. As antibiotic resistances are of major concern, we screened all samples for methicillin-resistant (MRSA) using qPCR, however, no signals above the detection limit were detected. Our study provides first comprehensive insight into the slit lamp microbiota. It underlines that slit lamps carry a highly diverse, skin-like bacterial microbiota and that thorough cleaning and disinfection after use is highly recommendable to prevent eye and skin infections.
Topics: Humans; Methicillin-Resistant Staphylococcus aureus; RNA, Ribosomal, 16S; Slit Lamp; Staphylococcal Infections; Staphylococcus aureus
PubMed: 34869057
DOI: 10.3389/fcimb.2021.745653 -
Scientific Reports Feb 2022This observational cohort study aimed to evaluate the progression pattern of diffuse chorioretinal atrophy (DCA) according to its severity. Highly myopic eyes with DCA... (Observational Study)
Observational Study
This observational cohort study aimed to evaluate the progression pattern of diffuse chorioretinal atrophy (DCA) according to its severity. Highly myopic eyes with DCA were graded according to its extent in the 532-nm (green) and 633-nm (red) wavelengths images of the Optos ultra-widefield scanning laser ophthalmoscope at baseline: grade 1 and 2 were defined when increased reflectance at peripapillary region, not beyond the fovea, were observed in red laser image only and in both laser images, respectively; grade 3 and 4 were defined when increased reflectance beyond the fovea were observed in red laser image only and in both laser images, respectively. A total of 307 eyes (221 patients) were included, and progression of myopic maculopathy during follow-up of ≥ 3 years was evaluated. The mean visual acuity and subfoveal choroidal thickness (CT) differed among DCA grades (P = 0.015 and P < 0.001); a higher DCA grade had worse visual acuity and thinner choroid. During follow-up, development of patchy atrophy (PA) was observed in 3.2%, 5.5%, 12.8%, and 23.2% (P < 0.001), while changes in lacquer crack (LC) and/or development of myopic macular neovascularization were observed in 20.6%, 29.1%, 33.3%, and 15.8% (P = 0.061) of 63, 110, 39, and 95 eyes with DCA grade of 1, 2, 3, and 4 at baseline, respectively. New LC formation tended to occur in eyes with thicker CT at baseline compared to PA development and progression of pre-existing LC. In highly myopic eyes with DCA, progression pattern of myopic maculopathy is different according to its severity and CT at baseline. Grading based on separated wavelength images of ultra-widefield scanning laser ophthalmoscope is useful to evaluate the severity and prognosis of DCA in Asian patients with high myopia.
Topics: Aged; Aged, 80 and over; Atrophy; Choroid; Disease Progression; Female; Follow-Up Studies; Humans; Macular Degeneration; Male; Middle Aged; Myopia; Ophthalmoscopes; Patient Acuity; Prognosis; Retina; Visual Acuity
PubMed: 35197535
DOI: 10.1038/s41598-022-07172-w