Surgical Depth Indicator With Rotating Marker for Calibration-Free Tracking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surgical navigation devices require calibration for each tool use, are prone to human error, and often lose connection with the navigation system due to tool rotation or obstruction, limiting compatibility with different tools and systems.
Innovation Solution
A generic intra-operative depth indicator device with a pair of end caps separated by a compressed spring, a guide tube, and a rotating tracking marker, allowing the surgical tool to be tracked without pre-calibration and maintaining connection regardless of obstructions, compatible with any navigation system or robotic arm.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a positional marker is attached to the tool and viewed by a navigation system, then the tool position can be tracked, but the connection is lost when the marker moves out of view due to tool rotation or obstruction
Solution Approach 1:
The patent transitions from 2D camera-based tracking to 3D time-of-flight sensing, adding a temporal dimension for depth measurement. This allows the system to track tool position in three-dimensional space regardless of marker orientation or occlusion, resolving the contradiction between reliable tracking and orientation adaptability
Solution Approach 2:
The patent replaces the optical-mechanical camera system with an optical sensing system based on time-of-flight measurement. This substitution enables direct depth measurement without relying on visual recognition of markers, maintaining tracking reliability while adapting to any tool orientation or position
2Measurement precision
If every tool is individually calibrated before use, then measurement accuracy is improved, but the process becomes time-consuming and prone to human error
Solution Approach 1:
The system performs self-calibration by automatically establishing the relationship between the depth indicator and the surgical tool during the procedure. The time-of-flight sensor continuously measures the distance between the indicator and tool, allowing the system to self-correct and maintain accuracy without manual calibration, thus reducing calibration time while preserving measurement precision
Solution Approach 2:
The patent incorporates a pre-configured depth indicator with known geometric relationships to the tool. This preliminary setup eliminates the need for time-consuming calibration during surgery, as the measurement system is already prepared to provide accurate depth information from the start of the procedure
3Ease of operation
If a fixed navigation marker is used on the tool, then tracking is simplified, but the marker may be obstructed or rotated out of view, losing connection with the navigation system
Solution Approach 1:
The patent replaces the camera-based visual tracking system with a time-of-flight optical sensing system. This substitution eliminates the need for visible markers, as the system directly measures the distance between the depth indicator and the surgical tool through optical time-of-flight, maintaining ease of operation while ensuring continuous reliable tracking regardless of tool orientation or obstructions
Data Source
AI summary
A depth-indicating device for determining the depth of insertion of a surgical tool comprising a pair of spaced apart end caps, separated by a compressed spring, with the surgical tool passing through axial openings in both end caps, and firmly attached to one of the end caps, but free to slide through the opening in the other. A guide tube is attached to the second endcap, such that the surgical tool can be guided to its operating position on a body part. The second end cap and guide tube are attached to a location having a known position relative to the body part. A tracking marker is attached to the first end cap such that its longitudinal position can be tracked using a remote racking camera. Since the surgical tool is attached to the first end cap, the tool position is also tracked by the tracking system.