Development and ex vivo evaluation of a novel suction-based bile duct biopsy device.

Background and Aims: Histologic examination is considered the reference standard for diagnosing cancer. However, bile ducts and other narrow passages in the human body are difficult to biopsy. Current biopsy forceps collect tissue that is directly in front of and perpendicular to the instrument. In bile ducts, this is particularly challenging because angling the forceps is limited by tight spaces. This study presents a novel biopsy device and methodology capable of collecting tissue from areas parallel to the instrument. Methods: We designed a biopsy device featuring a 4-lumen tube that can pass through the biopsy channel of an endoscope. The device includes several key components: a cutting blade, a mechanism to actuate the blade, a vacuum window for suction, and a tissue window for collecting samples. Testing was conducted using a bile duct phantom and a model constructed with porcine tissue. Results: The device was successfully manufactured and tested in a controlled, ex vivo environment. It demonstrated the ability to navigate narrow conduits like bile ducts effectively. In addition, the device was able to suction tissue parallel to the instrument, cut it precisely, and retrieve it for histologic analysis. Conclusions: This newly developed biopsy device offers the ability to obtain tissue samples from areas parallel to the biopsy instrument. The lateral biopsy window significantly expands the surface area for tissue collection, a critical feature for narrow conduits like bile ducts. This advancement is especially important for improving early cancer diagnosis in such areas, where delays can lead to worse prognosis.