Comparison of Smartphone Photography, Single-Lens Reflex Photography, and Field-Grading for Trachoma

Nesemann, John M; Seider, Michael I.; Snyder, Blake M.; Maamari, Robi N.; Fletcher, Daniel A.; Haile, Berhan A.; Tadesse, Zerihun; Varnado, Nicole E; Cotter, Sun Y.; Callahan, E. Kelly; Emerson, Paul M.; Margolis, Todd P.; Lietman, Thomas M.; Keenan, Jeremy D.

doi:10.4269/ajtmh.20-0386

Cited by 17 publications

(20 citation statements)

References 9 publications

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“…This smartphone attachment, the Corneal CellScope, has been shown to be valid and reproducible for assessment of trachoma. 26,27,39 As in previous reports, the quality of the smartphone images captured for this trial was good, with only 2% of photographs judged to be ungradable. 26,27 Ungradable photographs were more likely to have been obtained for younger children, suggesting some association with participant cooperation.…”

Section: Jama Network Open | Ophthalmologysupporting

confidence: 81%

Effect of Biannual Mass Azithromycin Distributions to Preschool-Aged Children on Trachoma Prevalence in Niger

et al. 2022

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IMPORTANCEBecause transmission of ocular strains of Chlamydia trachomatis is greatest among preschool-aged children, limiting azithromycin distributions to this age group may conserve resources and result in less antimicrobial resistance, which is a potential advantage in areas with hypoendemic trachoma and limited resources. OBJECTIVE To determine the efficacy of mass azithromycin distributions to preschool-aged children as a strategy for trachoma elimination in areas with hypoendemic disease. DESIGN, SETTING, AND PARTICIPANTS In this cluster randomized clinical trial performed from November 23, 2014, until July 31, 2017, thirty rural communities in Niger were randomized at a 1:1 ratio to biannual mass distributions of either azithromycin or placebo to children aged 1 to 59 months. Participants and study personnel were masked to treatment allocation. Data analyses for trachoma outcomes were performed from October 19, 2021, through June 10, 2022. INTERVENTIONS Every 6 months, a single dose of either oral azithromycin (20 mg/kg using heightbased approximation for children who could stand or weight calculation for small children) or oral placebo was provided to all children aged 1 to 59 months. MAIN OUTCOMES AND MEASURES Trachoma was a prespecified outcome of the trial, assessed as the community-level prevalence of trachomatous inflammation-follicular and trachomatous inflammation-intense through masked grading of conjunctival photographs from a random sample of 40 children per community each year during the 2-year study period. A secondary outcome was the seroprevalence of antibodies to C trachomatis antigens. RESULTS At baseline, 4726 children in 30 communities were included; 1695 children were enrolled in 15 azithromycin communities and 3031 children were enrolled in 15 placebo communities (mean [SD] proportions of boys, 51.8% [4.7%] vs 52.0% [4.2%]; mean [SD] age, 30.8 [2.8] vs 30.6 [2.6]months). The mean coverage of study drug for the 4 treatments was 79% (95% CI, 75%-83%) in the azithromycin group and 82% (95% CI, 79%-85%) in the placebo group. The mean prevalence of trachomatous inflammation-follicular at baseline was 1.9% (95% CI, 0.5%-3.5%) in the azithromycin group and 0.9% (95% CI, 0-1.9%) in the placebo group. At 24 months, trachomatous inflammation-follicular prevalence was 0.2% (95% CI, 0-0.5%) in the azithromycin group and 0.8% (95% CI, 0.2%-1.6%) in the placebo group (incidence rate ratio adjusted for baseline: 0.18 [95% CI, 0.01-1.20]; permutation P = .07).

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Section: Jama Network Open | Ophthalmologysupporting

confidence: 81%

Effect of Biannual Mass Azithromycin Distributions to Preschool-Aged Children on Trachoma Prevalence in Niger

et al. 2022

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“… 25 Ocular or blood samples that enable laboratory detection are primary ‘alternative indicator’ candidates, 10 as is the use of photography. 26 …”

Section: Discussionmentioning

confidence: 99%

Acceptability and perceived utility of different diagnostic tests and sample types for trachoma surveillance in the Bijagos Islands, Guinea Bissau

Sahota

Sanha

Last

et al. 2021

Transactions of the Royal Society of Tropical Medicine and Hygiene

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Background Trachoma is the leading infectious cause of blindness worldwide and is nearing elimination as a public health problem in Guinea Bissau. It is imperative that elimination is followed by a successful postvalidation surveillance programme. The aim of this study was to determine the acceptability and perceived utility of different diagnostic tests and sample types that could be used for postvalidation trachoma surveillance in the Bijagos Islands, Guinea Bissau. Methods Semistructured interviews with community members and stakeholders involved in trachoma elimination were followed by focus group discussions with community members, covering experiences with trachoma and views on trachoma diagnostic methods and sample types. Results In this setting, all diagnostic tests and sample types used for trachoma surveillance were generally considered acceptable by communities. A preference for laboratory-based testing and finger-prick blood samples was expressed as these results were considered more accurate and applicable to a range of diseases beyond trachoma. Conclusions Appropriate community and stakeholder engagement and communication regarding the purpose and processes around diagnostic practice prior to trachoma programme implementation are crucial for long-term successful disease-elimination efforts.

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“…Conventional digital SLR cameras often require attachable macro lenses to be able to take a close-up image of the tarsal conjunctiva and the photographer often needs a second person to hold the child and evert the lid. Though attachable lenses for smartphones have been tested, certain newer smartphones come with a macro lens embedded though the resolution is reportedly low [ 7 ]. The ICAPS system builds on previous technologies to create a hands-free, head-mounted camera system enabling a single person to evert an eyelid, take an image without touching the equipment, label and save it.…”

Section: Discussionmentioning

confidence: 99%

“…Another study evaluated an external attachment which allows the smartphone to take magnified images with greater image pixel-density dedicated to the eyelid [ 9 ]. It also used an external magnification attachment with supplementary light sources and a iPhone 4S smartphone, and reported 84.1% sensitivity and 97.6% specificity for TF [ 7 ]. Our system had high specificity, 98%, but lower sensitivity, 54%, compared to the field grade, though without a true gold standard assessment, we believe sensitivity and specificity could be misleading statistics.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of photography using head-mounted display technology (ICAPS) for district Trachoma surveys

Naufal¹,

Brady

Wolle³

et al. 2021

PLoS Negl Trop Dis

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Background As the prevalence of trachoma declines worldwide, it is becoming increasingly expensive and challenging to standardize graders in the field for surveys to document elimination. Photography of the tarsal conjunctiva and remote interpretation may help alleviate these challenges. The purpose of this study was to develop, and field test an Image Capture and Processing System (ICAPS) to acquire hands-free images of the tarsal conjunctiva for upload to a virtual reading center for remote grading. Methodology/Principal findings This observational study was conducted during a district-level prevalence survey for trachomatous inflammation—follicular (TF) in Chamwino, Tanzania. The ICAPS was developed using a Samsung Galaxy S8 smartphone, a Samsung Gear VR headset, a foot pedal trigger and customized software allowing for hands-free photography. After a one-day training course, three trachoma graders used the ICAPS to collect images from 1305 children ages 1–9 years, which were expert-graded remotely for comparison with field grades. In our experience, the ICAPS was successful at scanning and assigning barcodes to images, focusing on the everted eyelid with adequate examiner hand visualization, and capturing images with sufficient detail to grade TF. The percentage of children with TF by photos and by field grade was 5%. Agreement between grading of the images compared to the field grades at the child level was kappa = 0.53 (95%CI = 0.40–0.66). There were ungradable images for at least one eye in 199 children (9.1%), with more occurring in children ages 1–3 (18.5%) than older children ages 4–9 (4.2%) (χ2 = 145.3, p<0.001). Conclusions/Significance The prototype ICAPS device was robust, able to image 1305 children in a district level survey and transmit images from rural Tanzania to an online grading platform. More work is needed to improve the percentage of ungradable images and to better understand the causes of disagreement between field and photo grading.

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Comparison of Smartphone Photography, Single-Lens Reflex Photography, and Field-Grading for Trachoma

Cited by 17 publications

References 9 publications

Effect of Biannual Mass Azithromycin Distributions to Preschool-Aged Children on Trachoma Prevalence in Niger

Effect of Biannual Mass Azithromycin Distributions to Preschool-Aged Children on Trachoma Prevalence in Niger

Acceptability and perceived utility of different diagnostic tests and sample types for trachoma surveillance in the Bijagos Islands, Guinea Bissau

Evaluation of photography using head-mounted display technology (ICAPS) for district Trachoma surveys

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