Bone surface registration method for covered cartilage

Abstract

The invention aims to provide a bone surface registration method for a covered cartilage, so as to improve the registration accuracy. Specifically, the method comprises the following steps: the firstbone surface point set S1 of a to-be-registered bone surface sample point in an image coordinate system and the second bone surface point set S2 of the to-be-registered bone surface sample point in aworld coordinate system are obtained respectively; then the cartilage surface point cloud S3 of a to-be-registered bone auxiliary sample point in the world coordinate system is obtained by a positionsensor; next the first bone surface point set S1 and the cartilage surface point cloud S3 are registered to obtain an initial rotation matrix R1 and an initial translation vector T1; the second bone surface point set S2 and the cartilage surface point cloud S3 are registered to obtain a corrected rotation matrix R2 and a corrected translation vector T2; and finally, according to the initial rotation matrix R1, the initial translation vector T1, the corrected rotation matrix R2 and the correct translation vector T2, obtaining the following mapping relationship between the image coordinate system and the world coordinate system: the rotation matrix R=R2R1, and the translation vector T=R2T1+T2.

Description

technical field [0001] The invention belongs to the field of medical technology, and in particular relates to a registration method for bone surfaces covering cartilage in orthopedic surgery. Background technique [0002] Registration technique is the process of finding the optimal spatial transformation. Surgical navigation systems widely use registration technology to obtain the spatial mapping relationship between point sets, lines, surfaces or volumes. The registration subject usually changes according to the application scenario, including but not limited to between point sets, between point sets and surfaces, between high-dimensional features, between images, and so on. In the process of surgical navigation, it is usually necessary to obtain the coordinates of the target (organ, bone, muscle tissue, etc.) Get the coordinates of the target in the image coordinate system. [0003] The traditional bone surface registration method is as follows: collect the coordinates ...

AI Technical Summary

Problems solved by technology

It is not difficult to see that the two sets of point sets do not represent the same target, but two entities with close spatial positions. This difference will introduce errors for accurate registration; on the other hand, from the perspective of the local bone surface, the lack of obvious features And the marker points that can be accurately positioned, the selection of sample points naturally has errors, and it is difficult to accurately select only a small number of so-called sample point pairs for calculation

Images