Expandable Biopsy Needle Sleeve Mechanism
Solution Overview
Problem
Current biopsy devices face challenges in obtaining a large continuous tissue sample due to size limitations of the needle, which can result in repeated insertions causing trauma and sample compromise from fluid interference, and struggle to retain samples without vacuum suction.
Innovation Solution
A biopsy needle with expandable sleeves that allow for increased sample size and a rotating mechanism to assist in cutting and retaining samples, reducing the need for vacuum suction by expanding within a sheath and rotating axially during sampling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If vacuum suction is applied to retain the sample within the needle, then the sample can be retained during retraction, but fluids and small particles are drawn into the needle compromising the sample
Solution Approach 1:
The needle transitions from a collapsed state during insertion to an expanded state during sampling, dynamically changing its internal volume and cross-sectional area. This dynamic expansion creates retention features that hold the sample without requiring vacuum suction, thus preventing fluid and particle contamination while maintaining reliable sample retention.
Solution Approach 2:
The needle's internal geometry parameters change from a small collapsed configuration to a larger expanded configuration with increased radius and cross-sectional area. This parameter change allows the needle to accommodate larger tissue samples and provides internal structures that retain samples mechanically rather than through vacuum, eliminating the harmful effect of fluid suction.
2Quantity of substance
If the needle size is increased to obtain larger tissue samples, then more adequate samples can be taken, but the needle cannot pass through the sheath or delivery device
Solution Approach 1:
The needle is designed with a nested structure where the expanded needle can be collapsed into a compact configuration that fits within the sheath or delivery device. The needle transitions from a large expanded state for sampling to a small collapsed state for delivery, allowing the larger sample-taking capability while maintaining ease of delivery through constrained spaces.
Solution Approach 2:
The needle dynamically changes its size and configuration, transitioning from a collapsed delivery state to an expanded sampling state. This dynamic transformation allows the needle to pass through the sheath in a compact form while expanding to accommodate large tissue samples during the biopsy procedure.
3Quantity of substance
If the needle is extended multiple times to obtain sufficient sample, then adequate tissue can be collected, but increased trauma and multiple small samples are caused
Solution Approach 1:
The needle is pre-configured with expandable features and retention mechanisms that are activated during a single insertion. The expandable structure is prepared in advance to accommodate the full sample in one operation, eliminating the need for repeated insertions and reducing tissue trauma while ensuring adequate sample collection.
Solution Approach 2:
The needle maintains continuous sample retention capability throughout the sampling process through its expanded configuration and internal retention features. This continuous retention prevents sample loss and eliminates the need for multiple discrete sampling actions, allowing adequate tissue collection in a single continuous operation with minimal trauma.
Data Source
AI summary
An apparatus, comprising: a biopsy needle having a distal end and a proximal end, all or a portion of the biopsy needle being movable between a collapsed state and an expanded state; a sheath having a distal end and a proximal end, wherein the biopsy needle in the collapsed state is contained within the sheath, and in the expanded state at least the distal end of the biopsy needle extends from the distal end of the sheath; wherein the biopsy needle is provided with two or more sleeves, which at least partially overlap in the collapsed configuration and which cylindrically expand to provide an increased radius, relative to a radius in the collapsed state, for sampling in the expanded configuration, and wherein a cross section of the distal end of the biopsy needle in the expanded state is a substantially circular cross section.