Study of sleeve inner diameter to suppress backward heating for microwave surgical energy device

In modern surgery, microwave surgical energy devices are used for hemostasis and anastomosis. However, elongated heating region called backward heating distributes around the feeding line, and potentially causes undesirable heating to non-targeted, normal tissue. In order to suppress the backward heating, we considered use of a sleeve with microwave device. Large sleeve inner diameter is required to use the sleeve effectively. However, small sleeve inner diameter is preferable for use in surgery. In this study, numerical analyses were performed to investigate the optimum sleeve inner diameter. The results indicated over 4 mm inner diameter could suppress the backward heating.