Image-guided navigation devices, adapters and systems with optical distance sensor based markerless registration, depth detection, image-guided prediction and training models

A method for calibrating a system for an optical distance sensor-equipped imaging device, comprising:

• providing a lens assembly having a lens assembly proximal end and a lens assembly distal end the lens assembly comprises a housing mechanically couplable to the lens assembly proximal end wherein the lens assembly contains a continuous illumination path for transmitting light from the lens assembly proximal end to the lens assembly distal end and a continuous optical path relaying a field of view at the lens assembly distal end to an eyepiece at the lens assembly proximal end, and a sensor assembly disposed within the housing comprising an optical distance sensor operable to receive a distance-sensing light in a first optical distance wavelength band within a field-of-view via an optical path of the lens assembly, wherein the lens assembly disposed comprises a time-of-flight sensor operable to determine a distance based on a time delay or a phase shift between an emitted distance-sensing light and a returned distance-sensing light and is further operable to receive distance-sensing light in a first wavelength band within the field of view via the optical path of the lens assembly, and further wherein an illumination interface is provided that is operable to deliver time-of-flight illumination within the first wavelength band into the illumination path of the lens assembly;
• providing a calibration fixture device comprising a target portion with a plurality of fiducial markers of known geometry distributed along a surface of known geometry;
• providing at least one processing circuit operable to receive raw values from a time-of-flight sensor, positioning the lens assembly such that a calibration fixture target portion is positioned within the field of view of the time-of-flight sensor;
• computing and storing a three-dimensional mapping function for mapping one or more aligned raw values obtained from the time of flight sensor to a corresponding physical three-dimensional coordinate relative to a reference position on the lens assembly;
• using the three-dimensional mapping function to compute a calibration target surface geometry using the raw values received from the time of flight sensor;
• computing a plurality of error metrics by spatially correlating a computed calibration target surface geometry with a known calibration target surface geometry and computing their discrepancy;
• comparing the plurality of error metrics to a corresponding plurality of predetermined acceptance criteria;
• and
• conditioning the operability of the optical distance sensor-equipped imaging device for taking geometric measurements of targets disposed within a lens assembly field of view on the acceptability of the error metrics.

A guidance system comprising:

• a housing;
• a lens assembly disposed within the housing having a lens assembly proximal end and a lens assembly distal end wherein the lens assembly contains a continuous illumination path for transmitting light from the lens assembly proximal end to the lens assembly distal end and a continuous optical path relaying a field of view at the lens assembly distal end to an eyepiece at the lens assembly proximal end;
• an assembly disposed within the housing comprising a time-of-flight sensor operable to determine a distance based on a time delay or a phase shift between an emitted distance-sensing light and a returned distance-sensing light, wherein a time-of-flight sensor is operable to receive distance-sensing light in a first wavelength band within the field of view via the optical path of the lens assembly;
• an illumination interface disposed within the housing, wherein the illumination interface is operable to deliver time-of-flight illumination within the first wavelength band into the illumination path of the lens assembly;
• a calibration fixture device, the calibration fixture comprising a target portion with a plurality of fiducial markers of known geometry distributed along a surface of known geometry;
• at least one processing circuit operable to receive raw values from the time-of-flight sensor;
• at least one display operable to receive and render data from the processing circuit;
• and
• a processor operable to compute and store a three-dimensional mapping function for mapping one or more aligned raw values obtained from the time of flight sensor to a corresponding physical three-dimensional coordinate relative to a reference position on the lens assembly, wherein the guidance system is used to measure three-dimensional locations of a plurality of target points visible within the field of view of the lens assembly.

A computer-implemented method of training a model for pre-procedure preparation, comprising:

• a. obtaining a training dataset comprising
• i. pre-procedure scans,
• ii. intra-procedure depth maps and visible-light images acquired through an optical distance sensor-equipped imaging device, and
• iii. procedure plans and associated outcomes;
• b. training a machine learning model to learn a mapping from the pre-procedure scans and the intra-procedure depth maps to one or more planning outputs selected from:
• recommended target locations, recommended trajectories, safety margins, and risk scores;
• and
• c. storing parameters of trained machine learning model operable to infer the planning outputs from a new pre-procedure scan.

An arthroscopic guidance system, comprising:

• a. an arthroscope having a rod-lens optical path, an illumination channel, and an instrument channel;
• b. an optical distance sensor optically coupled to the rod-lens optical path and operable to generate a depth map of an intra-articular field of view;
• c. a visible-light imaging sensor optically coupled to the rod-lens optical path;
• and
• d. a processing circuit operable to register the depth map to a pre-procedure scan of a joint and to display a navigation view including at least one planned tunnel trajectory overlaid relative to articular surfaces.