Validity of a Telemedicine System for the Evaluation of Acute-Phase Retinopathy of Prematurity

Abstract

The present strategy to identify infants needing treatment for retinopathy of prematurity (ROP) requires repeated examinations of at-risk infants by physicians. However, less than 10% ultimately require treatment. Retinal imaging by nonphysicians with remote image interpretation by nonphysicians may provide a more efficient strategy.OBJECTIVE To evaluate the validity of a telemedicine system to identify infants who have sufficiently severe ROP to require evaluation by an ophthalmologist. DESIGN, SETTING, AND PARTICIPANTS An observational study of premature infants starting at 32 weeks' postmenstrual age was conducted. This study involved 1257 infants with birth weight less than 1251 g in neonatal intensive care units in 13 North American centers enrolled from May 25, 2011, through October 31, 2013.INTERVENTIONS Infants underwent regularly scheduled diagnostic examinations by an ophthalmologist and digital imaging by nonphysician staff using a wide-field digital camera. Ophthalmologists documented findings consistent with referral-warranted (RW) ROP (ie, zone I ROP, stage 3 ROP or worse, or plus disease). A standard 6-image set per eye was sent to a central server and graded by 2 trained, masked, nonphysician readers. A reading supervisor adjudicated disagreements. MAIN OUTCOMES AND MEASURESThe validity of grading retinal image sets was based on the sensitivity and specificity for detecting RW-ROP compared with the criterion standard diagnostic examination.RESULTS A total of 1257 infants (mean birth weight, 864 g; mean gestational age, 27 weeks) underwent a median of 3 sessions of examinations and imaging. Diagnostic examination identified characteristics of RW-ROP in 18.2% of eyes (19.4% of infants). Remote grading of images of an eye at a single session had sensitivity of 81.9% (95% CI, 77.4-85.6) and specificity of 90.1% (95% CI, 87.9-91.8). When both eyes were considered for the presence of RW-ROP, as would routinely be done in a screening, the sensitivity was 90.0% (95% CI, 85.4-93.5), with specificity of 87.0% (95% CI, 84.0-89.5), negative predictive value of 97.3%, and positive predictive value of 62.5% at the observed RW-ROP rate of 19.4%. CONCLUSIONS AND RELEVANCEWhen compared with the criterion standard diagnostic examination, these results provide strong support for the validity of remote evaluation by trained nonphysician readers of digital retinal images taken by trained nonphysician imagers from infants at risk for RW-ROP. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01264276

Telemedicine for Evaluation of Retinopathy of Prematurity

“…Detractors of the use of RDFI in ROP evaluation cite the difficulty in imaging the retinal periphery, limited image quality in certain circumstances (eyes with poor dilation, media haze, or dark fundus pigmentation), variability in image interpretation even among experienced clinicians, 17 insufficient evidence, 18 and high implementation cost (hardware, software, and nonphysician personnel). However, the results of the recently published e-ROP Study 11 provide strong support for an RDFI paradigm.…”

“…4 A number of reports have addressed various aspects of this issue. [5][6][7][8][9][10][11] However, the pace of implementation of RDFI with TM for ROP evaluation in the ophthalmic community has outstripped the pace of systematic evaluation of the approach. A consensus "standard of care " has not yet been established.…”

“…11 However, the variability in ROP image grading among even experienced physicians is widely recognized. 7 In the absence of a formally recognized certification process and oversight construct, uniform training, licensing, and liability considerations preclude the routine use of nonphysician graders at this time.…”

Training retinal imagers for retinopathy of prematurity (ROP) screening

“…10 The purpose of this study was to describe the retinal imagers' training and certification process and examine the factors that affected image acquisition and image quality in the e-ROP study.…”

“…Such a system presents a way to offer preterm infants worldwide a safe 13 means for image acquisition and an effective system for ROP evaluation. 10,15 Imaging has also provided an important teaching aid for families and medical staff to illustrate the infant's ROP status, reinforcing the seriousness of the disorder and need for careful follow-up. …”