TY - JOUR
T1 - A machine vision method for automated alignment of fundus imaging systems
AU - Moscaritolo, Michele
AU - Knezevich, Frederick P.
AU - Zimmer-Galler, Ingrid
AU - Jampel, Henry
AU - Zeimer, Ran
PY - 2010/11
Y1 - 2010/11
N2 - ■ BACKGROUND AND OBJECTIVE: To report a method to track the pupil in three axes simultaneously prior to imaging the fundus. ■ PATIENTS AND METHODS: The system is based on parallax optical alignment to detect the center of the pupil. The system consists of two cameras acquiring pupil images from two distinct directions and an operator-supervised algorithm to derive the coordinates of the pupil center and output of commands to drive a three-axes computer-controlled stage. The system was tested in a cohort of 45 individuals 61 ± 15 years of age, 26 with and 19 without glaucoma. The tracking was performed without pharmacologic pupil dilation. ■ RESULTS: The variability of the pupil center determination (assessed by the standard deviation) was ± 0.19 and ± 0.33 mm for the vertical and horizontal directions, respectively. The processing time of the algorithm was 0.75 msec. The tracking converged to within a preset tolerance of ± 0.5 mm in 45 of the 45 eyes. ■ CONCLUSION: Image acquisition and processing of pupil images can be used to align fundus imaging systems rapidly, accurately, and with minimal operator intervention.
AB - ■ BACKGROUND AND OBJECTIVE: To report a method to track the pupil in three axes simultaneously prior to imaging the fundus. ■ PATIENTS AND METHODS: The system is based on parallax optical alignment to detect the center of the pupil. The system consists of two cameras acquiring pupil images from two distinct directions and an operator-supervised algorithm to derive the coordinates of the pupil center and output of commands to drive a three-axes computer-controlled stage. The system was tested in a cohort of 45 individuals 61 ± 15 years of age, 26 with and 19 without glaucoma. The tracking was performed without pharmacologic pupil dilation. ■ RESULTS: The variability of the pupil center determination (assessed by the standard deviation) was ± 0.19 and ± 0.33 mm for the vertical and horizontal directions, respectively. The processing time of the algorithm was 0.75 msec. The tracking converged to within a preset tolerance of ± 0.5 mm in 45 of the 45 eyes. ■ CONCLUSION: Image acquisition and processing of pupil images can be used to align fundus imaging systems rapidly, accurately, and with minimal operator intervention.
UR - http://www.scopus.com/inward/record.url?scp=79953247247&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79953247247&partnerID=8YFLogxK
U2 - 10.3928/15428877-20100929-05
DO - 10.3928/15428877-20100929-05
M3 - Article
C2 - 20954644
AN - SCOPUS:79953247247
SN - 1542-8877
VL - 41
SP - 607
EP - 613
JO - Ophthalmic Surgery Lasers and Imaging
JF - Ophthalmic Surgery Lasers and Imaging
IS - 6
ER -