Forceps-type mini-positron emission tomography (mini-PET) has been proposed as an intraoperative device for examining metastatic lymph nodes in the treatment of esophageal cancer. Although this forceps-type mini-PET detects cancer by radiation measurement, the scissor-like tip of the device affects the measurement accuracy. Therefore, to improve the detection sensitivity of the forceps-type mini-PET without depending on the operator, we fabricated a forceps tip mechanism using a parallel-link for parallel opening and closing motions, and verified the parallel motion and the force required for opening and closing. Consequently, we confirmed parallel motion from the opening and closing widths of the tip detectors. In addition, we confirmed that the forces required for opening and closing were significantly smaller than those required for the conventional mechanism.

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