Objective
To report on a 6-year experience with wide-field digital imaging based telemedicine (WFDI telemedicine) to reduce the risk
for blindness from retinopathy of prematurity (ROP).
Methods
Wide-angle digital fundus cameras (RetCam 120, Massie Lab, Pleasanton, CA, USA) were installed in five neonatal intensive
care units (NICUs) in Germany. All prematures at risk were screened with WFDI, and the local ophthalmologists were asked to
continue binocular indirect ophthalmoscopy (BIO) according to the German guidelines. Image data were coded and transferred
to the Reading Centre in Regensburg. Image evaluation and additional BIO of infants with suspected treatment-requiring ROP
(STR-ROP i.e. threshold ROP zone II, prethreshold ROP zone I (type-1 ROP according to ETROP), and ROP possibly requiring treatment
but not reliably classifiable from the images) were performed by paediatric ophthalmologists at the Reading Centre. ROP was
classified following ICROP, ETROP, and revised ICROP criteria. Outcome measures were incidence of clinically relevant ROP
(CR-ROP, i.e. any ROP up to mid-peripheral zone III, ≤ stage 3+), sensitivity to detect STR-ROP, and positive predictive value
to detect treatment-requiring ROP (TR-ROP).
Results
In total, 1,222 prematures at risk were screened (mean BW 1395 g, SD ±507 g; mean GA 30 wks, SD ±3 wks). The overall incidence
of CR-ROP was 27.6% (71.8% mild = stage 1 to 3 without plus disease, 15.7% prethreshold = type-1 ROP according to ETROP, 12.5%
threshold according to ICROP). Zone I disease was present in 3.3%, zone II disease in 76.5%, and zone III disease in 20.2%.
According to ETROP, 95 infants were type-1 or type-2 ROP; 67.4% type-1 ROP, and 32.6% type-2 ROP. Of all 1,222 infants, 3.5%
received treatment. Following ETROP (not applied in the study), 5.3% would have been treated. The sensitivity for detecting
STR-ROP was 100%, and the positive predictive value for TR-ROP 82.4% (28/34) at the time of the first referral (28 infants,
≤ stage 3+ in zone I or II).
Conclusion
All TR-ROP was detected in time, showing the potential of our telemedical screening program. The overall incidence of CR-ROP
was comparable to ROP incidences reported in other West European countries.
Keywords Retinopathy of prematurity (ROP) - Wide-field digital imaging (WFDI) - RetCam 120 - Telemedicine - Sensitivity - Positive predictive value
Support: Bayerische Sparkassenstiftung, München, Germany; Bayerische Landesstiftung, München, Germany; Deutsche Forschungsgemeinschaft
(DFG Lo 457/4-1,2), and Iris Medical, Mountain View, CA, USA
The authors do not have any financial interest in the RetCam120 or Massie Laboratories, Pleasanton, CA 94588, USA or Clarity
Medical Systems Inc, Pleasanton, CA 94588, USA
C: (925)-519-6655, www.claritymsi.com
Parts of the contents were presented at the Annual Meetings 2003 and 2007 of the Association for Research in Vision and Ophthalmology
ARVO, at the Annual Meeting of the European Paediatric Ophthalmological Society EPOS 2003, at the Annual Meeting 2004 of the
German Ophthalmological Society DOG, and at the World Ophthalmology Congresses WOC 2006 and 2008