Beveled needle position and pose estimation based on optical coherence tomography in ophthalmic microsurgery

Abstract

The needle position and pose is essential information in ophthalmic microsurgery. Estimation of these parameters is still an open problem, which hinders the application of various robot-assisted surgeries, such as autonomous injection. This paper presents a method to estimate the position and pose of beveled needle using three-dimensional Optical Coherence Tomography (OCT) image cube. The incomplete 3D point cloud of beveled needle obtained from OCT image cube is used to reconstruct the needle by fitting the projection of needle points based on its geometric features. We demonstrate the applicability of our method in ophthalmic injection surgery using ex vivo pig eyes and evaluate the accuracy of position and pose information using a micromanipulator.

Precision Needle Tip Localization Using Optical Coherence Tomography Images for Subretinal Injection

“…The main goal of the image preprocessing is to segment the needle fragment from tissue in each B-scan image. Based on the needle shadow principle from our previous work [24], [25], the needle and retinal surface can be segmented with dissolution of noise influence in each B-scan image when the needle is still above the retina. The position of the needle points can be calculated from the index of OCT Bscan and pixels position in current OCT B-scan image.…”