Siyang Zuo

MRI-Compatible Rigid and Flexible Outer Sheath Device with Pneumatic Locking Mechanism for Minimally Invasive Surgery

To reduce the invasiveness of surgery, we developed an outer sheath device using a flexible toothed link and pneumatic locking mechanism that works with flexible devices used in minimally invasive surgery. The outer sheath can be switched between flexible and rigid modes, and the angle of its tip can be controlled by a nylon wire. All parts of this device are made of plastic and are MRI-compatible. We manufactured a sheath prototype, 300 mm long, with a 20-mm outer diameter, and an 8-mm inner diameter. Experiment results showed that the outer sheath can protect tissues from high insertion force and secure the path for flexible devices. It can follow a curved path with a reasonable radius.

Developing essential rigid-flexible outer sheath to enable novel multi-piercing surgery

We have developed a new generation device called rigid-flexible outer sheath with multi-piercing surgery (MPS) to solve the issues of tissue closure, triangulation, and platform stability in natural orifice transluminal endoscopic surgery (NOTES), and the problems of restricted visual field, organ damage, and removing a resected organ from body in needlescopic surgery (NS). The shape of the flexible outer sheath can be selectively locked by a novel pneumatic shapelocking mechanism. Major features include four directional flexion at the distal end, four working channels, and suction and water jet functions. The insertion part of the prototype is 330 mm long with a 25 mm maximum outer diameter. The outer sheath system has successfully preformed in vivo experiment using a swine on partial gastrectomy. The advanced outer sheath system has shown great promise for solving NOTES and NS issues.

Nonmetallic rigid-flexible outer sheath with pneumatic shapelocking mechanism and double curvature structure

Single port access (SPA) surgery is a laparoscopic procedure using only one transumbilical-placed port. Natural orifice transluminal endoscopic surgery (NOTES) offers the possibility of surgery without visible scars. To address the access and stability problems in SPA and NOTES, we developed a device called rigid-flexible outer sheath. This sheath can be switched between flexible and rigid modes by a novel pneumatic shapelocking mechanism, and it has a double curvature structure that enables it to flex in four directions at the distal end and three directions on the rigid-flexible shaft. The insertion part of the prototype is 300 mm long with a 20 mm outer diameter, and the part is equipped with four working channels. In vivo experiments using a swine show that the outer sheath has high potential for solving access and stability problems. We expect that the outer sheath will be useful for SPA and NOTES.

Nonmetallic Guide Sheath with Negative Pressure Shapelocking Mechanism for Minimally Invasive Image-Guided Surgery

To address the access and stability problems in endoscopic surgery, we developed a device called rigid–flexible outer sheath. This sheath can be switched between flexible and rigid modes by a novel pneumatic shapelocking mechanism, and it has a double curvature structure that enables it to flex in four directions at the distal end and three directions on the rigid–flexible shaft. The prototype is 300 mm long with a 20 mm outer diameter, and equipped with four working channels. All parts of this device are made of plastic and are MRI-compatible. Insertion performance in a phantom experiment was evaluated in an open MRI environment. The experimental results showed that the outer sheath could follow a curved path, and that the sheath was compatible with an MRI environment. This means the outer sheath should be useful in surgery with MRI guidance.

MRI Compatible Rigid-flexible Outer Sheath Device Using Pneumatic Locking Mechanism for Endoscopic Treatment

To reduce the invasiveness of surgery, we developed an outer sheath device using flexible toothed link and vacuum pressure locking mechanism for flexible devices in endoscopic surgery. The outer sheath can be switched to flexible mode and rigid mode. Furthermore, the angle of its forward part can be controlled using nylon wire. All of the parts of this device are made by plastic so that it has excellent compatibility with MRI. We manufacture a prototype of sheath with 20mm in the outer diameter, 8mm in the inner diameter and 300mm long. The experiment showed that our mechanism could switch flexible mode and rigid mode, and the outer sheath was sufficient to fix its shape by our mechanism.

Nonmagnetic Rigid and Flexible Outer Sheath with Pneumatic Interlocking Mechanism for Minimally Invasive Surgical Approach

We developed a nonmagnetic rigid and flexible outer sheath with pneumatic interlocking mechanism using flexible toothed links and a wire-driven bending distal end. The outer sheath can be switched between rigid and flexible modes easily depending on surgical scenes, and the angle of its distal end can be controlled by three nylon wires. All components of flexible parts are made of MRI-compatible nonmagnetic plastics. We manufactured the device with 300-mm long, 16-mm outer diameter, 7-mm inner diameter and 90-mm bending distal end. Holding power of the device in rigid mode was maximum 3.6 N, which was sufficient for surgical tasks in body cavity. In vivo experiment using a swine, our device performed smooth insertion of a flexible endoscope and a biopsy forceps into reverse side of the liver, intestines and spleen with a curved path. In conclusion, our device shows availability of secure approach of surgical instruments into deep cavity.