A Pneumatic Tactile Ring for Instantaneous Sensory Feedback in Laparoscopic Tumor Localization

Abstract

We aim to achieve intraoperative localization of an early-stage gastric tumor that cannot be visually detected during laparoscopic surgery. In this study, we developed and evaluated a pneumatic tactile ring, which is a clinically applicable tactile device to provide instantaneous feedback from a tactile sensor directly manipulated by a surgeon. It was designed to be worn on the finger of the manipulating hand and to present pressure to the finger pad. It is lightweight, cost-effective, disposable, and sterilizable. We also developed a compact pneumatic drive unit to control the pressure and investigated its fundamental performance. The bandwidth of the pressure control was at least 1.3 Hz with a controllable range of up to 79.7 kPa. Moreover, a psychophysical experiment was performed to obtain the Weber ratio of the pressure and evaluate the effectiveness of the instantaneous tactile feedback of the sensor output through the tactile ring. The Weber ratio was 0.40 at the reference pressure of 22.7 kPa. The provided tactile feedback significantly reduced the absolute localization error and increased participants' confidence in their answers. It was shown that the tactile feedback through the ring is effective in laparoscopic tumor localization.

SuP‐Ring: A pneumatic tactile display with substitutional representation of contact force components using normal indentation

“…For normal element interaction only, the Weber fraction was at least 0.5. This value is slightly higher than the obtained WF of a similar tactile display that also applies pressure to the user's finger 17 . The WF of the tactile device should be constant for reference pressures, as expected in Weber's law.…”

“…We decided to generate the pressure above 15.38 kPa (with the offset values) to achieve better performance of the pneumatic control module. In tissue palpation, the natural tissue probing could involve quasi‐static motions, which usually do not exceed frequencies of 1 Hz 17 . In this study, we also focused on representing the tactile feedback for slow exploring motions, which surgeons could control.…”

“…Regarding the feasibility of SuP‐Ring in surgical applications, the device could be utilised in a disposable manner because of its low‐cost manufacturing. Moreover, the device components were made of biocompatible materials, similar to a tactile ring device, 17 which was confirmed to be capable of sterilisation. Because the device was lightweight and a strap was used to mount the device on the user's finger, the SuP‐Ring has high wearability.…”

“…Fukuda et al. proposed a ring‐type tactile display using pneumatic power 17 . Based on the instantaneous sensory feedback provided by the displays, the surgeon was able to detect the intraoperative tumour.…”

A Review of Pneumatic Actuators Used for the Design of Medical Simulators and Medical Tools

“…Some applications are listed in [48]. Other samples are introduced in [62] where pneumatic actuation is used to provide tactile feedback to achieve intraoperative localization of an early-stage gastric tumor that cannot be visually detected during laparoscopic surgery, or in [63] where a pneumatic actuated haptic glove featuring silicone-made cavities located at the fingertips and the center of the palm of the user make users perceive soft skins with different shape, stiffness, and homogeneity. On the other end of the teleoperation chain, it can be used also for force sensing like in [64] where a force measurement is performed thanks to the air pressure variation inside a pneumatic balloon in contact with an object.…”