Tissue Resector With Cutting Wire and Outer Cannula
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current morcellators used in gynecological surgeries have small inner diameters, limiting the rate of tissue aspiration and prolonging procedures, causing pain and inefficiency in removing uterine polyps and fibroids.
Innovation Solution
A tissue resector system with a cannula and a cutting wire, where the cutting wire is positioned within the cannula, providing a larger cross-sectional area for aspiration, allowing at least 50% of the cannula's area to be open for tissue removal, and can be used with either manual or power-driven instruments.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a power-driven morcellator with an inner cannula and blade is used to remove uterine polyps and fibroids, then tissue can be cut and aspirated, but the small inner diameter of the inner cannula limits the aspiration rate and prolongs the procedure
Solution Approach 1:
The device divides the single cannula into two functional parts: an outer cannula for structural support and an inner cutting element (wire or blade) for tissue sectioning. This segmentation allows the outer cannula to have a larger diameter optimized for aspiration while the inner cutting element performs the morcellation function, thereby increasing the aspiration rate without compromising tissue removal capability.
Solution Approach 2:
The cutting wire or blade is positioned inside the outer cannula, creating a nested configuration where the inner cutting element operates within the larger outer cannula. This nesting allows the outer cannula to provide a larger aspiration lumen while the inner element performs cutting, resolving the contradiction between aspiration rate and tissue removal effectiveness.
2Productivity
If the inner cannula diameter is increased to improve aspiration rate, then tissue removal efficiency improves, but the device complexity and difficulty of insertion increase
Solution Approach 1:
By segmenting the cannula into outer and inner components with distinct functions, the outer cannula can be optimized for large-diameter aspiration while the inner cutting element handles the complex cutting function. This segmentation allows each component to be simpler in its specific function while the overall system achieves high productivity.
Solution Approach 2:
The outer cannula serves multiple functions: providing structural support, enabling aspiration with a large lumen, and guiding the inner cutting element. This multi-functionality reduces the need for additional complex components, thereby increasing aspiration rate without proportionally increasing device complexity.
3Area of stationary object
If a cutting wire within a single cannula is used, then the cross-sectional area for aspiration is increased, but the cutting mechanism becomes more complex compared to a simple rotating blade
Solution Approach 1:
Instead of using a traditional rotating blade that requires complex drive mechanisms, the invention inverts the approach by using a cutting wire that can be advanced and retracted through the cannula. The wire is deployed through the outer cannula, engaged with tissue, and pulled through to complete the cut, then retracted. This inversion simplifies the cutting mechanism while maintaining an large aspiration cross-sectional area.
Solution Approach 2:
The cutting function is extracted from a complex rotating blade mechanism and implemented through a simpler wire that is advanced through the cannula. The wire is deployed from the inner cannula through the outer cannula, engages tissue at the opening, and is pulled through to cut. This extraction of the cutting function to a simpler wire mechanism reduces overall device complexity while maintaining large aspiration area.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system enables faster and more efficient removal of uterine polyps and fibroids, reducing procedure duration and pain by allowing higher aspiration rates and improved tissue collection.
Implementation Method 1
tissue that is introduced (e.g., by suction, etc.) into the opening
Data Source
Figure 1A~5C
Figure 2A~2C
Figure 2D
AI summary
A tissue resector includes an outer cannula with a cutting wire disposed therein. The outer cannula includes an opening that is configured to be associated with a cutting element of the cutting wire in such a way that when tissue is drawn into the opening of the cannula, a cutting element of the cutting wire can be rotated past the opening to engage and cut into and through the tissue. The outer cannula and the cutting wire may also be configured to enable aspiration of the tissue. A tissue resector according to this disclosure may be used with a hand-held, hand-operated rooter.