Interobserver and Intertest Agreement in Telemedicine Glaucoma Screening with Optic Disk Photos and Optical Coherence Tomography

Abstract

Purpose: To evaluate interobserver and intertest agreement between optical coherence tomography (OCT) and retinography in the detection of glaucoma through a telemedicine program. Methods: A stratified sample of 4113 individuals was randomly selected, and those who accepted underwent examination including visual acuity, intraocular pressure (IOP), non-mydriatic retinography, and imaging using a portable OCT device. Participants’ data and images were uploaded and assessed by 16 ophthalmologists on a deferred basis. Two independent evaluations were performed for all participants. Agreement between methods was assessed using the kappa coefficient and the prevalence-adjusted bias-adjusted kappa (PABAK). We analyzed potential factors possibly influencing the level of agreement. Results: The final sample comprised 1006 participants. Of all suspected glaucoma cases (n = 201), 20.4% were identified in retinographs only, 11.9% in OCT images only, 46.3% in both, and 21.4% were diagnosed based on other data. Overall interobserver agreement outcomes were moderate to good with a kappa coefficient of 0.37 and a PABAK index of 0.58. Higher values were obtained by experienced evaluators (kappa = 0.61; PABAK = 0.82). Kappa and PABAK values between OCT and photographs were 0.52 and 0.82 for the first evaluation. Conclusion: In a telemedicine screening setting, interobserver agreement on diagnosis was moderate but improved with greater evaluator expertise.

Cost-Effectiveness of Screening for Open Angle Glaucoma Compared With Opportunistic Case Finding

“…The latter is currently considered the most frequently used and also the most precise imaging device for detecting glaucoma. 9,11,20 The results obtained in the present study may not be highly conclusive, but we believe they are clinically significant. Several factors that may have increased the costs of the screening method while offering clear benefits to newly diagnosed cases.…”

Diagnostic Accuracy and Detection Rate of Glaucoma Screening with Optic Disk Photos, Optical Coherence Tomography Images, and Telemedicine

“…The random selection resulted in a list of 4113 individuals, but only 1006 (24.5%) were finally examined at the screening center ( Figure 1 ). The demographic characteristics of the sample are summarized in Table 1 and described in more detail elsewhere [ 15 ]. The distribution between genders reflected the slightly larger number of females than males in the population, and approximately 40% were aged 55–64 years and 65–74 years, respectively, while 20% of the sample was older than 74 years.…”

“…A previous study conducted by our group in a similar setting encountered a low participation rate (25.5%) for several reasons [ 10 ], and, consequently, we considered a random selection of more than 4000 persons from the census necessary to obtain a sample of 1000 examinations. A detailed description of the sample calculation for the global study is described elsewhere [ 15 ]. A sample of 222 persons was estimated to be adequate, 74 screened as positive and 148 individuals screened as negative, to evaluate the diagnostic accuracy of the screening program.…”

“…Participants signed an informed consent form before entering the study and completed a health questionnaire. The details of the screening program are described in a previous publication [ 15 ]. Visual acuity and intraocular pressure (IOP) with an air-puff tonometer (Topcon CT80, Topcon Corporation, Oakland, NJ, USA) were also measured.…”

“…A group of 16 trained ophthalmologists was asked to evaluate the quality of each image (non-evaluable, poor, fair, or good) and the presence or absence of pathological signs, globally specifying the signs identified, on easy-to-complete forms on the DYSEO platform. The specific fields to be defined by evaluators and classification methods have been previously described [ 15 ].…”