Proposal of Magnetic Actuator for Brush Cytology and Anchoring Function Applicable to Capsule-type Medical Device

Abstract

  In this article, a novel magnetic actuator is proposed for brush cytology done using capsule endoscopy. Its basic structure is a lead screw mechanism consisting of a bolt with a permanent magnet and a lead screw nut. The nut is equipped with a cytology brush and an anchoring mechanism that can stop the capsule in a specific place. When rotating magnetic fields are applied, the turning motion of the bolt due to magnetic torque is converted to the linear motion of the nut, which causes both the brush to project outward and the anchors to extend. If the rotational direction of the magnetic fields is switched periodically, the brush can exhibit a reciprocating motion and scrape the mucus off. To increase the amount of samples collected, an additional small magnet was attached to the brush tip. As a result, this improved brush with induced rotational vibration could drastically enhance the performance of cytology.