Abstract
Purpose :
To compare the usable image area acquired on nonmydriatic eyes of subjects with and without ocular disease using a prototype widefield (WF) slit-scanning ophthalmoscope (SSO) (ZEISS, Dublin, CA) and two standard commercial nonmydriatic fundus cameras, VISUCAM® 524 (ZEISS, Jena, Germany) and VISUCAM®PRO NM (ZEISS, Jena, Germany).
Methods :
Eighteen (18) nonmydriatic eyes of 9 subjects over 50 years of age were imaged using a ZEISS prototype WF SSO with the macula centered. The system acquires images that subtend a 90° FOV as measured from the cornea. Comparison images were acquired using standard commercial nonmydriatic fundus cameras, VISUCAM 524 and VISUCAMPRO NM. Both VISUCAM 524 and VISUCAMPRO NM acquire images that subtend a 45° FOV. Eight (8) subjects had type 2 diabetes mellitus, 2 eyes had cataracts, and 2 eyes were pseudophakic. The usable image area was evaluated by an expert grader. Regions determined to be poor/unusable in image quality were marked and the remaining portion of the image was defined as usable. For the WF SSO system, the known image distortion was used to convert from area in pixels to area in mm2. VISUCAM 524 and VISUCAMPRO NM were assumed to be distortion free when converting from pixels to area in mm2.
Results :
The usable image area for each device is summarized in Table 1 and Figure 1. For all 18 eyes, the average usable area for WF SSO was 327 mm2, for VISUCAM 524 was 68.5 mm2, and for VISUCAMPRO NM was 60.6 mm2.
Conclusions :
The ZEISS WF SSO provides a larger usable image area than both VISUCAM 524 and VISUCAMPRO NM for nonmydriatic eyes.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.