Endoscopic Mucosal Resection Device Cap Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional endoscopic mucosal resection techniques face challenges in effectively removing pedunculated and sessile polyps without damaging surrounding tissue or muscle layers, often resulting in complications like perforation, bleeding, and incomplete tissue removal.
Innovation Solution
A resection device with a cap assembly featuring a resection loop channel and track system that allows for precise capture and cauterization of tissue, ensuring only the affected tissue is removed while minimizing damage to deeper layers, using a cap assembly with a working channel and resection loop track that can pivot and accommodate a resection loop for parallel alignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional EMR techniques are used to remove sessile polyps, then the polyps can be removed, but the muscularis layer may be damaged causing perforation
Solution Approach 1:
The cap assembly is divided into multiple components: a first cap with a resection loop channel, a second cap with a resection loop track, and a flared section. This segmentation allows each component to perform a specific function - the track guides the loop wire, the flared section captures tissue, and the channel allows loop passage - thereby enabling precise control of the resection depth to avoid damaging the muscularis layer while effectively removing sessile polyps
Solution Approach 2:
The resection loop track acts as an intermediary mechanism between the operator's control and the tissue resection process. The track constrains the loop wire to move in a controlled manner, ensuring that the loop closes at a precise location within the cap assembly. This intermediary structure enables accurate control of resection depth, preventing penetration into the muscularis layer while still achieving complete removal of the polyp tissue
2Manufacturing precision
If the wire loop cut is made deeper to ensure complete tissue removal, then more cancerous tissue is removed, but the muscularis layer may be injured causing perforation
Solution Approach 1:
The cap assembly is pre-configured with a resection loop track that defines the exact path and depth of the loop wire closure. Before the resection occurs, the track is already in place to guide the loop wire to close at a specific location that ensures adequate tissue clearance (more than 2 mm of cancerous tissue removal) while stopping before reaching the muscularis layer. This preliminary structuring of the cutting path eliminates the need to guess the appropriate depth during the procedure
Solution Approach 2:
The invention replaces the conventional free-moving wire loop system with a constrained system where the loop wire travels through a defined track. This mechanical substitution transforms the uncontrolled depth penetration issue into a controlled process where the track's geometry dictates the exact resection depth, ensuring consistent and safe tissue removal without risking perforation of the muscularis layer
3Object-affected harmful factors
If the wire loop cut is made shallower to avoid muscularis layer injury, then perforation is prevented, but not enough cancerous tissue is removed requiring additional procedures
Solution Approach 1:
The resection loop track is pre-designed with specific geometric dimensions that guarantee adequate resection depth. The track's shape and position within the cap assembly are calculated to ensure that when the loop wire closes along the track, it removes more than 2 mm of cancerous tissue while stopping before reaching the muscularis layer. This preliminary design eliminates the need for additional procedures by ensuring complete tissue removal in a single procedure
Solution Approach 2:
The resection loop track creates a precise copy or replica of the desired resection path. By molding the track with the exact geometry needed for safe and complete resection, the system reproduces the ideal cutting trajectory every time, ensuring consistent removal of adequate tissue depth without varying into dangerous or insufficient cuts that would require repeat procedures
4Ease of operation
If saline solution is injected to raise sessile polyps, then the polyps can be grasped more easily, but the procedure complexity increases
Solution Approach 1:
The invention extracts the grasping function from the conventional EMR process. Instead of requiring saline injection to lift the polyp for grasping, the cap assembly's flared section and resection loop track directly capture and secure the sessile polyp as it is suctioned into the cap. The polyp is grasped by the geometry of the cap itself, eliminating the need for the additional saline injection step and simplifying the overall procedure
Data Source
Figure 1A~1C
Figure 2A~2B
Figure 2C~2D
AI summary
The resection device includes an elongate member (508) having a proximal end, a distal end, and a lumen extending from the proximal end to the distal end. The device further includes a cap assembly (100) configured to be coupled to the distal end of the elongate member, The cap assembly may include a first cap (102)defining a resection loop channel (204) and a distal end having a first opening. The assembly may further include a second cap (104)configured to receive a portion of the first cap. The second cap includes a distal end having a second opening. A distal portion of the first cap and a distal portion of the second cap may cooperate to define a resection loop track (112) for receiving a resection loop (402).