US-20260123995-A1 - NAVIGATION SYSTEM, JIG, AND PROGRAM

US20260123995A1US 20260123995 A1US20260123995 A1US 20260123995A1US-20260123995-A1

Abstract

A navigation system includes an acquisition unit configured to acquire information on a position and a posture of a first sensor detected based on a signal of the first sensor, and information on a target attachment position and a target attachment posture of the first sensor with respect to a position and a posture of a second sensor detected based on a signal of the second sensor, the first sensor being inserted into an attachment portion of a first jig, which has a surface having a shape corresponding to a surface of a first bone, in a first orientation predetermined with respect to the first jig, and the second sensor being inserted into an attachment portion of a second jig, which has a surface having a shape corresponding to a surface of a second bone, in a second orientation predetermined with respect to the second jig.

Inventors

Kensuke YAMAUCHI
Masanori HARIYAMA
Nobuhiro YODA

Assignees

TOHOKU UNIVERSITY

Dates

Publication Date: 20260507
Application Date: 20221031

Claims (13)

1 . A navigation system comprising: an acquisition unit configured to acquire information on a position and a posture of a first sensor detected based on a signal of the first sensor, and information on a target attachment position and a target attachment posture of the first sensor with respect to a position and a posture of a second sensor detected based on a signal of the second sensor, the first sensor being inserted into an attachment portion of a first jig, which has a surface having a shape corresponding to a surface of a first bone, in a first orientation predetermined with respect to the first jig, and the second sensor being inserted into an attachment portion of a second jig, which has a surface having a shape corresponding to a surface of a second bone, in a second orientation predetermined with respect to the second jig; a derivation unit configured to derive a first relative position and a first relative posture of the first sensor with respect to the target attachment position and the target attachment posture based on the target attachment position, the target attachment posture, and the position and the posture of the first sensor; an information generation unit configured to generate a three-dimensional coordinate axis image representing the target attachment position and the target attachment posture and a three-dimensional coordinate axis image representing the first relative position and the first relative posture; and a display unit configured to display the three-dimensional coordinate axis image representing the target attachment position and the target attachment posture and the three-dimensional coordinate axis image representing the first relative position and the first relative posture.
2 . The navigation system according to claim 1 , wherein the second jig is a dental splint.
3 . The navigation system according to claim 1 , wherein the information generation unit generates numerical value information representing a difference between the target attachment position and the first relative position, and the display unit further displays the numerical value information.
4 . The navigation system according to claim 1 , wherein the information generation unit generates character information representing a movement direction in which a difference between the target attachment position and the first relative position is reduced, and the display unit further displays the character information.
5 . The navigation system according to claim 1 , wherein the information generation unit generates an image of a line connecting the target attachment position and the first relative position, and the display unit further displays the image of the line.
6 . The navigation system according to claim 1 , wherein the sensors are magnetic sensors.
7 . The navigation system according to claim 1 , wherein the first bone is a skull, and the second bone is a maxilla.
8 . The navigation system according to claim 1 , wherein the acquisition unit acquires information on a position and a posture of the first bone detected based on the signal of the first sensor attached to the first bone and information on a position and a posture of the second bone detected based on the signal of the second sensor attached to the second bone, the derivation unit derives a second relative position and a second relative posture of the second bone with respect to the position of the first bone based on the information on the position and the posture of the first bone and the information on the position and the posture of the second bone, and derives a target relative position and a target relative posture of the second bone with respect to the position and the posture of the first bone based on a movement amount predetermined with respect to an initial value of the second relative position and a rotation amount predetermined with respect to an initial value of the second relative posture, the information generation unit generates a three-dimensional coordinate axis image representing the target relative position and the target relative posture and a three-dimensional coordinate axis image representing the second relative position and the second relative posture, and the display unit displays the three-dimensional coordinate axis image representing the target relative position and the target relative posture and the three-dimensional coordinate axis image representing the second relative position and the second relative posture.
9 . (canceled)
10 . A jig comprising: a first jig including: an attachment portion configured to allow a sensor to be inserted in a predetermined orientation; and a surface having a shape corresponding to a surface of a bone on skull side to be joined; and a second jig including: an attachment portion configured to allow a sensor to be inserted in a predetermined orientation; and a surface having a shape corresponding to a surface shape of a bone on dentition side to be joined.
11 . The jig according to claim 10 , wherein the first jig includes a first of the attachment portions configured to allow a first of the sensors to be inserted in a first orientation predetermined with respect to the first jig, and a first of the surfaces having a shape corresponding to a surface of a first of the bones; and on skull side, the second jig includes a second of the attachment portions configured to allow a second of the sensors to be inserted in a second orientation predetermined with respect to the second jig, and a second of the surfaces having a shape corresponding to a surface shape of a second of the bone on dentition side, and the orientation of the first of the sensors inserted into the first of the attachment portions of the first jig while being joined to the first of the bones on skull side and the orientation of the second of the sensors inserted into the second of the attachment portions of the second jig while being joined to the second of the bones on dentition side are the same orientation.
12 . A non-transitory storage medium storing a program causing a computer to execute procedures comprising: acquiring information on a position and a posture of a first sensor detected based on a signal of the first sensor, and information on a target attachment position and a target attachment posture of the first sensor with respect to a position and a posture of a second sensor detected based on a signal of the second sensor, the first sensor being inserted into an attachment portion of a first jig, which has a surface having a shape corresponding to a surface of a first bone, in a first orientation predetermined with respect to the first jig, and the second sensor being inserted into an attachment portion of a second jig, which has a surface having a shape corresponding to a surface of a second bone, in a second orientation predetermined with respect to the second jig; deriving a first relative position and a first relative posture of the first sensor with respect to the target attachment position and the target attachment posture based on the target attachment position, the target attachment posture, and the position and the posture of the first sensor; generating a three-dimensional coordinate axis image representing the target attachment position and the target attachment posture and a three-dimensional coordinate axis image representing the first relative position and the first relative posture; and displaying the three-dimensional coordinate axis image representing the target attachment position and the target attachment posture and the three-dimensional coordinate axis image representing the first relative position and the first relative posture.
13 . The non-transitory storage medium according to claim 12 , wherein the procedures further comprise: acquiring information on a position and a posture of the first bone detected based on the signal of the first sensor, and information on a position and a posture of the second bone detected based on the signal of the second sensor, the first sensor being inserted into the attachment portion of the first jig, which has the surface having the shape corresponding to the surface of the first bone, in the first orientation predetermined with respect to the first jig, and the second sensor being inserted into the attachment portion of the second jig, which has the surface having the shape corresponding to the surface of the second bone, in the second orientation predetermined with respect to the second jig; deriving a relative position and a relative posture of the second bone with respect to the position of the first bone based on the information on the position and the posture of the first bone and the information on the position and the posture of the second bone, and deriving a target relative position and a target relative posture of the second bone with respect to the position and the posture of the first bone based on a movement amount predetermined with respect to an initial value of the relative position and a rotation amount predetermined with respect to an initial value of the relative posture; generating a three-dimensional coordinate axis image representing the target relative position and the target relative posture and a three-dimensional coordinate axis image representing the relative position and the relative posture; and displaying the three-dimensional coordinate axis image representing the target relative position and the target relative posture and the three-dimensional coordinate axis image representing the relative position and the relative posture.

Description

TECHNICAL FIELD The present invention relates to a navigation system, a jig, and a program. BACKGROUND ART As image processing technology advances, it has become common to perform preoperative planning (three-dimensional simulation) prior to surgery. For example, in orthognathic surgery, a surgeon may separate a maxilla (Le Fort I bone fragment) from a skull. The surgeon accurately moves the maxilla to a target relative position with respect to a position of the skull, and fixes the maxilla to the skull again at the target relative position. In preoperative planning of such orthognathic surgery, a skull model and a maxilla model of a patient are moved and rotated on a screen of a display unit of a planning device (information processing device), and the target relative position of the maxilla with respect to an actual position of the skull is examined by a planner (doctor) for a purpose of achieving good occlusion and aesthetic facial appearance of the patient. Navigation surgery is one of methods for reflecting a result of a target relative position of preoperative planning in actual surgery. In optical navigation surgery, a position of a surgical instrument is detected in real time by distance measurement using infrared rays reflected by a reflector attached to the surgical instrument. Further, it has been studied to apply magnetic (electromagnetic (EM) ) navigation surgery to paranasal sinus surgery, catheter treatment, and the like. In magnetic navigation surgery, a position of a surgical instrument (non-magnetic) is detected in real time by a magnetic tracking system based on an output of a magnetic sensor attached to the surgical instrument (see Non Patent Document 1). Patent Document 1 discloses a surgical system that executes optical or magnetic navigation in craniomaxillofacial surgery. Patent Document 2 discloses an optical maxillary alignment system using a mouthpiece type target and a camera. CITATION LIST Patent Documents Patent Document 1: US 2017/0000505Patent Document 2: US 2009/0220122 Non Patent Document Non Patent Document 1:“magnetic three-dimensional measurement system AURORA”, [online], Aug. 2, 2022, Advanced Systems Co., Ltd., [searched on Aug. 2, 2022], Internet <URL:http://www.asco.jp/02aurora.htm> SUMMARY OF INVENTION Technical Problem However, Patent Document 1 discloses a position detection reference module having a complicated shape as a detection reference module used in a magnetic navigation system. There is a problem that the position detection reference module having such a complicated shape interferes with surgery. In addition, the position detection reference module having a shape exposed to the outside detects a position away from an actual position of a bone as a position of the bone. Therefore, there is a problem that even if the bone is accurately moved to the position guided by the navigation system, the position is not an accurate target position, and thus a surgeon cannot align the position of the bone with the accurate target position. Further, in Patent Document 1, the position detection reference module for detecting a position of a bone fragment to be moved is attached to a cutting guide for cutting and separating a jaw bone from a skull. When such a cutting guide is used, there is a problem that it takes time and effort to align an upper jaw and a lower jaw, and it is difficult to visually dispose a sensor at a target attachment position determined in preoperative planning because there is no noticeable mark in the bone for alignment in many cases. Therefore, it is not preferable that the position detection reference module be attached to the cutting guide. In Patent Document 2, a maxilla is aligned using a mouthpiece type dental splint (mouthpiece). In such alignment surgery, a maxilla and a mandible are preferably integrated. However, a shape of a target having four light sources for alignment is a shape exposed to the outside from the dental splint, similar to the position detection reference module of Patent Document 1, so that the distance measurement using a camera can be performed. Therefore, the target not only obstructs the surgery, but also the target is away from the position of the dentition, and thus bones may not be accurately aligned with each other. In addition, the target is exposed to the outside from the dental splint, and thus the position of the target as an origin of the alignment may be shifted, and it is difficult to accurately align the bones. In Patent Document 2, surgeons and caregivers may be crowded around the head of a patient. In such a case, in an optical navigation surgery using a reflector exposed to the outside of the dental splint as in Patent Document 2, optical shielding may occur due to a surgeon or the like. That is, infrared rays reflected by the reflector attached to a surgical instrument may be shielded by the surgeon or the like. When the optical shielding occurs, the infrared rays cannot be used for the distance meas