Advantage and Core Benefit
- Improved surgical efficiency: insertion of the sheath into the stenosis after balloon dilation greatly facilitates the subsequent insertion and placement of the drainage stent, thus significantly improving surgical efficiency
- Applicability for other uses: not only for endoscopic bile duct drainage (ERBD), but also for endoscopic ultrasound-assisted gallbladder drainage (EUS-BD), which is also expected to prevent bile leakage after dilation.
- Combination of existing technologies: can be easily created by combining existing balloon catheter and sheath technologies, which are also advantageous in terms of development costs.
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Background and Technology
As pancreatic and cholangiocarcinoma progresses, the bile ducts become narrowed, resulting in cholangiectasis, which reduces bile flow and causes jaundice and cholangitis. Endoscopic bile duct drainage (ERBD) for bile duct stricture involves the placement of a stent in the bile duct using an endoscope. The standard procedure for stenting is generally as follows: (1) balloon catheter is reached to the stenosis; (2) the tip of the balloon catheter is used to break through the stenosis and inflate the balloon to widen it; (3) the balloon is deflated and removed, and a stent is inserted and placed in the stenosis. However, when the balloon is removed and the stent is inserted in step (3) of this procedure, restenosis of the dilated stenosis often occurs, making it difficult to break through the stent in many cases (see figure).
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The researchers therefore devised a new surgical device, the sheath-loaded dilated balloon catheter, which prevents restenosis by simultaneously inserting a sheath into the dilated stenosis after balloon dilatation and squeezing the balloon. This device, which greatly facilitates the insertion and placement of stents for drainage, can be fabricated using a combination of existing balloon catheter and sheath technology (right-hand figure).
Furthermore, this sheath-loaded dilated balloon catheter can be applied for ultrasound endoscopic gallbladder drainage. By pushing the entire sheath into the gallbladder while dilated with the balloon catheter and implanting the sheath, it is expected to improve safety by preventing bile leakage after dilation.
Sheath-loaded dilated balloon catheter
- (1) Balloon dilatation (2) Insertion of the sheath into the area to be drained as soon as the balloon is deflated (3-4) Smooth placement of the stent through the sheath.
Patent & Publication
Pending in Japan
Patent & Publication
Kato et al., Digestive Endoscopy, 2022 Mar;34(3): e34-e35
Kato et al., Digestive Endoscopy Open. 2024 Apr; 4(1): e303
Researcher
Dr. Akihisa Kato (Nagoya City University)
Expectations
We wish to collaborate with medical device development companies that develop balloon catheters and sheaths. Specifically, we would like to develop a product that combines a sheath with a balloon catheter with the following structure
- The sheath should have a strength and structure that is resistant to twisting, especially if it has a mesh structure
- The inner diameter of the sheath should be 6.0 or 7.5 Fr, suitable for balloon loading
- The tip of the sheath should be of a construction suitable for indwelling for a period while passing through a dilated stenosis
Clinical evaluation and support can be provided by the University. Web meetings with the researchers regarding the invention/project are also possible.
Project No.WL-04828