Comparison of vertical cup-to-disc ratio estimates using stereoscopic and monoscopic cameras

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

Test accuracy of human papillomavirus in urine for detection of cervical intraepithelial neoplasia

The objective was to assess the diagnostic test accuracy of high-risk human papillomavirus (hrHPV) testing of self-collected urine and cervicovaginal samples for the detection of cervical intraepithelial neoplasia grade 2 or higher (CIN2+). We recruited a convenience sample of women 25 to 65 years of age who were undergoing clinically indicated colposcopy at two medical centers in North Carolina between November 2016 and January 2019. Women with normal cytology results and positive hrHPV results were also recruited. Urine samples, self-collected cervicovaginal samples, provider-collected cervical samples, and cervical biopsy samples were obtained from all enrolled women. Samples were tested for hrHPV DNA using the Onclarity assay (Becton Dickinson, Sparks, MD). Biopsy samples were histologically graded as CIN2+ or <CIN2. We calculated the sensitivity and specificity for detection of CIN2+ and assessed agreement between sample collection methods. We included 307 women (median age, 36 years) with valid histology results and triplematched urine, self-collected cervicovaginal, and provider-collected cervical hrHPV results; 83 women (27%) had CIN2+. Urine-based hrHPV testing correctly identified 80% of CIN2+ cases (95% confidence interval [CI], 71 to 88%) using the PCR cycle threshold (CT) established for provider-collected cervical samples, but sensitivity remained below the estimates for self-collected cervicovaginal and provider-collected cervical samples (both 94% [95% CI, 89 to 99%]). Using a higher CT cutoff value of ≤40, 90% sensitivity was achieved for urine-based hrHPV testing. Agreement between results for urine samples and self-collected cervicovaginal samples (kappa = 0.58) or provider-collected cervical samples (kappa = 0.54) was moderate. Urinebased hrHPV testing may be a promising approach to improve cervical cancer screening coverage, especially among women with limited access to health care