Research factors that influence on rotational operation of endovascular treatment devices

Abstract

In endovascular therapy, guidewires and catheters are maneuvered manually, which often results in injury to blood vessels. One of the causes is that the behavior of the device differs from the operator's expectation. To avoid injuring blood vessels, the relationship between the input and output angles of the guidewire tip must be defined clearly. We have fabricated an experimental device that can give data on guidewire strain energy (deformation) and load individually. We defined the load index as the sum of the product of the load and arc length of the guidewire where the load is applied. The guidewire rotation angle when the guidewire was subjected to a 1° manipulation (φ001) and a 180° manipulation (φ180) were investigated. Based on the result of that measurement, we created a response surface for φ001 and φ180. The ratio of the first-order term of the load index to that of the strain energy on the response surface of φ001 and φ180 was 14.25 and 2.42, respectively. Results showed that the load index has a significant effect on both φ001 and φ180. If the strain energy and load index of the guidewire in a vessel can be estimated from intraoperative images, the input angle and output angle of the tip required to rotate the guidewire in the vessel can be predicted from the response surface in the present study. This will contribute to reducing the possibility of incorrect guidewire operation caused by the inexperience of a surgeon.