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Background: The use of monoscopic cameras for glaucoma screening is increasing due to their portability, lower cost, and non-mydriatic capabilities. However, it is important to compare the accuracy of such devices with stereoscopic cameras that are used clinically and are considered the gold standard in optic disc assessment. The aim of this study is to compare vertical cup-to-disc ratio (VCDR) estimates obtained using images taken with a monoscopic and stereoscopic camera., Methods: Participants were selected from the Tema Eye Survey. Eligible subjects had images of at least one eye taken with two cameras. They were classified as meeting the glaucoma threshold if an eye had a VCDR estimate >97.5th percentile, corresponding to >0.725 for this population. Hence, we used 0.725 as the cutoff to group eyes into two categories: positive and negative. We calculated sensitivity, specificity, and predictive values of VCDR assessed by expert readers at a reading center for monoscopic photos using stereoscopic photos as the gold standard., Results: Three hundred and seventy-nine eyes of 206 participants were included in the study. Most participants were female (60.2%) and the most common age group was 50-59 years (36.4%). Sixteen eyes met the glaucoma threshold (VCDR > 0.725). Of these, the VCDR estimates of 14 eyes (87.5%) disagreed on the glaucoma threshold from the two cameras. The sensitivity to detect glaucoma with the monoscopic camera was 14.3% (95% CI: 4.0, 40.3)., Conclusions: The low sensitivity of monoscopic photos suggests that stereoscopic photos are more useful in the diagnosis of glaucoma., (© 2021. The Author(s), under exclusive licence to The Royal College of Ophthalmologists.)

Purpose: Trichiasis, the potentially visually disabling result of chronic trachoma, is a leading cause of blindness world wide. Surgery can repair trichiasis, but recurrence of severe trichiasis (lashes touching the cornea) following surgery is likely to have immediate vision threatening consequences. Azithromycin use post-surgery appeared to be beneficial against recurrences but there were a mix of severe, moderate, and mild trichiasis; the specific effect on prevention of severe, vision-threatening recurrence is unknown. This randomized, clinical trial determined if treating trichiasis surgical patients with oral azithromycin compared to usual care (topical tetracycline) resulted in a reduction in severe recurrence of trichiasis to one year., Methods: In a rural, trachoma hyperendemic district in Ethiopia, 1452 trichiasis patients age 18 or older presenting for surgery were randomly allocated to azithromycin, single 1 gram dose, versus topical tetracycline twice per day for six weeks. The outcome was recurrent severe trichiasis, defined as lashes touching the cornea, or more than 5 lashes touching the globe, to one year., Results: Patients randomized to receive azithromycin had significantly fewer severe recurrences, 4.2/100 person years overall, compared to those randomized to topical tetracycline, 7.9/100 person years (p < 0.01)., Conclusions: A single dose of azithromycin has been shown to reduce severe post-surgical trichiasis recurrence rates to one year and should become standard post surgical treatment.

Background: Trachoma is the leading infectious cause of blindness. Routes of transmission remain unclear. In this study, the relationship between Chlamydia trachomatis Amplicor-positive nasal discharge and Amplicor-positive ocular swabs was investigated (Amplicor; Roche, Indianapolis, IN)., Methods: A longitudinal study was conducted in Tanzania and The Gambia. Eyes were graded for active trachoma; ocular swabs were taken to test for C. trachomatis. Children with visible nasal discharge had swabs taken of this material. Participants were offered systemic antibiotics. Two months after treatment, participants were re-examined., Results: Of the 1128 children participating, 188 (17%) had nasal discharge. Among 188 children with nasal discharge, 64 (34%) nasal swabs were PCR positive. There was a strong correlation between active disease/ocular chlamydial positivity and positive nasal discharge. Children with Amplicor-positive ocular swabs were 9.9 times more likely to have Amplicor-positive nasal discharge than were children without ocular positivity (95% CI: 4.34-22.53). Two months after treatment, 16% had an Amplicor-positive ocular swab. Children with positive nasal discharge at baseline were 5.2 times more likely to have an Amplicor-positive ocular swab at 2 months than were children without Amplicor-positive nasal discharge at baseline (95% CI: 1.54-17.23), after adjusting for baseline ocular positivity, gender, and study site., Conclusions: Nasal discharge may provide a source of reinfection with C. trachomatis, after antibiotic treatment for trachoma, either through transfer of secretions from nose to eye or from nasal secretions transferred to bed sheets or dirty clothes and back to the eye; alternatively, nasal discharge may be an indicator of severe persistent ocular chlamydial infection that is not cleared with a single dose of antibiotics.