Abstract
Purpose :
In vitreoretinal surgery, surgeons manipulate sharp surgical instruments in close proximity to the retina, with the potential for unintentional tissue-instrument interactions causing tissue damage. The principles of collision avoidance may be applied to ophthalmic surgery in order to minimize the potential for tissue damage. Accurate assessment of the position of the surgical instruments and intraocular tissues is requisite.
Methods :
Tracking of surgical instruments and intraocular tissues may be performed via two approaches; optical tracking via surgical stereo cameras to track the retina, and electromagnetic sensing to track the surgical instrument. A rigid registration of the two reference systems allows for the determination of the distance between the tip of the instrument and the retina. We created a virtual and navigable three-dimensional environment, generated in real time, for the visualization of distances. We assessed the accuracy of a registered optical-electromagnetic tracking system in measuring distance in real time. The evaluation of the algorithm has been performed at the macroscale with a tracking volume size of 46x56x30 cm.
Results :
With an exemplar chosen ground truth distance of 15cm, the optical tracker detected distances with an average accuracy of 97.15%, with a mean absolute error of 4.28mm and a standard deviation of 1.5mm. The registered camera-sensor system showed an average distance detection accuracy of 92.84%, with a mean absolute error of 1.07 cm and a standard deviation of 1.068cm.
Conclusions :
These data indicate that this approach has the potential to provide reliable real-time surgical guidance by assessing surgical instrument positional data relative to intraocular tissues. Experiments at the microscale using a surgical microscope will yield additional data on the potential utility of this approach in the microsurgical environment.
This is a 2021 ARVO Annual Meeting abstract.