Visual and tactile feedback for a direct-manipulating tactile sensor in laparoscopic palpation

Needle consideration in umbilical two-port laparoscopic percutaneous extraperitoneal closure for patent processus vaginalis of children: hook-needle or forcep-needle

BACKGROUND

Although umbilical two-port laparoscopic percutaneous extraperitoneal closure for the treatment of processus vaginalis patency of children has been verified to be safe and effective, the improvements of technical skills and instruments have been always on their ways. Recently, forcep-needle has begun to be used. In this study, we compared forcep-needle with hook-needle in this minimal invasive procedure for children suffered from hernia or hydrocele, with the aim to evaluate the instrumental convenience of the two needles.

METHODS

From July 2021 to May 2022, we begun to use hook-needle or forcep-needle in umbilical two-port laparoscopic percutaneous extraperitoneal closure for children suffered from hernia or hydrocele. The hook-needle group included nineteen children and the forcep-needle group included twenty-four ones. The data of the patients age, sex, side, operation time, postoperative hospital-stay, follow-up time, postoperative complications were evaluated. Common silk thread was used to encircle the internal ring preperitoneally.

RESULTS

There were no statistical differences between the two groups for the following items: age, sex, side, operation time, postoperative hospital-stay and postoperative complications (P > 0.05). The follow-up time of the hook-needle group was longer than that of the forcep-one (P = 0.0020). No open transfer happened for all the patients. One hydrocele boy in the hook-needle group reoccurred 1 month postoperatively due to the peritoneal broken. The single pole retreating of the hook-needle accompanied with chaotic movements, while for that of the forcep-needle, the double-arm retreating movements were more orderly. The outer surface of the forcep-needle was smooth without restrain, as for the hook-needle, an inlaid barb held the danger of brokening the peritoneum.

CONCLUSION

In our preliminary experience of umbilical two-port laparoscopic percutaneous extraperitoneal closure using a hook-needle or a forcep-needle, in view of the instrumental convenience and safety, the double-arm and smooth outer surface designs of the forcep-needle contained more spatial orientation perceptions and safety.

A Review on Tactile Displays for Conventional Laparoscopic Surgery

Laparoscopic surgery (LS) is a minimally invasive technique that offers many advantages over traditional open surgery: it reduces trauma, scarring, and shortens recovery time. However, an important limitation is the loss of tactile sensations. Although some progress has been made in robotic-assisted minimally invasive surgery (RMIS) setups, RMIS is still not widely accessible. This review aims to identify which tactile display technologies have been proposed and experimentally validated for the restoration of tactile sensations during conventional laparoscopic surgical tasks. We conducted a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We identified relevant articles published over the past 10 years through a search on Web of science, Scopus, IEEE Xplore Digital, and PubMed repositories. A total of 143 articles met the inclusion criteria and 24 were included in the final review. From the reviewed articles, we classified the proposed tactile displays into two categories based on the use of skin contact: (i) skin tactile displays, which include vibrotactile, skin-indentation, and grip-feedback devices, and (ii) non-contact tactile displays based on visualization tools. This survey aims to contribute to further research in the area of tactile displays for laparoscopic surgery by providing a better understanding of the current state of the art and identifying the remaining challenges.

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

BACKGROUND

Shear force is important for tumour detection and can contribute to minimally invasive surgery (MIS). A popular method uses lateral skin stretch to produce shear force but has some limitations.

METHODS

We have developed a ring-type pneumatic tactile display that employs normal indentation substituted for lateral skin stretch to represent normal and shear feedback, called SuP-Ring. Psychophysical experiments were conducted to evaluate how users perceive the provided feedback and the effectiveness of SuP-Ring in tumour localisation.

RESULTS

The experimental results show that the participants could perceive the provided normal and shear feedback well. Shear feedback enables users to enhance their performance in localising the tumour and normal feedback could contribute to ensuring the safety requirements in MIS.

CONCLUSIONS

The proposed tactile display could be useful for intraoperative tumour localisation and has the potential to be used in a wide variety of applications.

A tactile sensor using the acoustic reflection principle for assessing the contact force component in laparoscopic tumor localization

PURPOSE

Localization of an early stage gastric tumor is easily performed in conventional open surgery, whereas it is a difficult procedure in minimally invasive surgery (MIS). A tactile sensor could allow precise resection of the tumor in laparoscopic surgery. The safety of medical tools should be ensured in MIS. Moreover, boundary conditions such as a double-ended beam without a supporting rigid base during tissue palpation were hardly considered. Thus, we suppose that it is informative to assess the normal force and shear force for practical tumor detection considering the boundary condition.

METHODS

In this study, a tactile sensor with normal and shear force measurement functions using the acoustic reflection principle was developed for gastric tumor detection in MIS. The developed tactile sensor was tested using an artificial phantom of the stomach without a supporting rigid base to evaluate the force response of the sensor in intraoperative tumor localization.

RESULTS

The developed sensor is safe for human tissue and can be sterilized. The experimental results show that the developed tactile sensor has the capability to measure normal and shear forces. In the gastric tumor detection test, the shear force of the sensor was more stable and highly responsive to the tumor position than the normal force, which is greatly affected by the bending of the tissue during the operation.

CONCLUSIONS

A two-axis tactile sensor using the acoustic reflection principle was assembled for tissue palpation in MIS. The results showed that the developed sensor is suitable for tumor detection, indicating that the shear force information of the developed sensor is more useful in MIS for early stage gastric tumor localization.

Haptic Intracorporeal Palpation Using a Cable-Driven Parallel Robot: A User Study

OBJECTIVE

Intraoperative palpation is a surgical gesture jeopardized by the lack of haptic feedback which affects robotic minimally invasive surgery. Restoring the force reflection in teleoperated systems may improve both surgeons' performance and procedures' outcome.

METHODS

A force-based sensing approach was developed, based on a cable-driven parallel manipulator with anticipated seamless and low-cost integration capabilities in teleoperated robotic surgery. No force sensor on the end-effector is used, but tissue probing forces are estimated from measured cable tensions. A user study involving surgical trainees (n = 22) was conducted to experimentally evaluate the platform in two palpation-based test-cases on silicone phantoms. Two modalities were compared: visual feedback alone and both visual + haptic feedbacks available at the master site.

RESULTS

Surgical trainees' preference for the modality providing both visual and haptic feedback is corroborated by both quantitative and qualitative metrics. Hard nodules detection sensitivity improves (94.35 ± 9.1% vs 76.09 ± 19.15% for visual feedback alone), while also exerting smaller forces (4.13 ± 1.02 N vs 4.82 ± 0.81 N for visual feedback alone) on the phantom tissues. At the same time, the subjective perceived workload decreases.

CONCLUSION

Tissue-probe contact forces are estimated in a low cost and unique way, without the need of force sensors on the end-effector. Haptics demonstrated an improvement in the tumor detection rate, a reduction of the probing forces, and a decrease in the perceived workload for the trainees.

SIGNIFICANCE

Relevant benefits are demonstrated from the usage of combined cable-driven parallel manipulators and haptics during robotic minimally invasive procedures. The translation of robotic intraoperative palpation to clinical practice could improve the detection and dissection of cancer nodules.

Softness sensing probe with multiple acoustic paths for laparoscopic surgery

PURPOSE

Surgeon's tactile sense is restricted during laparoscopic surgery. We aim to develop a softness sensing probe for endometriosis. Identification of the boundary of the lesion through a tactile sensor during laparoscopic surgery can provide an appropriate cut line, reducing excessive cut.

METHOD

We expand our acoustic reflection-based sensing to the proposed probe, which has three force-sensing points to measure the softness of the object. The compensation of the sensor posture with the three sensor outputs was additionally proposed. This sensor has a simple structure and no electrical elements in the part inserted into the body. The sensing principle was verified using the theoretical analysis. Fundamental experiment to make the estimation model and evaluation test with the simulated environment were conducted.

RESULT

The fundamental experiment showed that different softness can be estimated and that leave-one-out cross-validation resulted that the root-mean-square-error of the softness estimation was 31.5 kPa within the range of 7.5° in the probe posture. Samples which have similar softness as normal and lesioned uterus were used for the evaluation test using laparoscopic box trainer and a general trocar. Six participants operated the sensor, and the results showed that the samples were significantly discriminated by the softness estimated.

CONCLUSION

The experimental results showed that the sensor can estimate the softness while compensating the posture and discriminate model samples of normal and lesioned uterus in the simulated environment, indicating the possibility of boundary identification between normal and lesioned tissues during laparoscopic surgery of endometriosis.

An Acquaintance with An Aging Society

Low birth rates and higher life expectancy have been ravaging Japanese society. This article summarizes some of the latest medical knowledge and assistive activities, with a nod toward one nonprofit organization’s efforts to deliver better home healthcare to the elderly through housing and technologies, in the world’s first super-aging society. The response to the transforming society requires a combination of familiar customs and new technologies that create a favorable environment for mobility and continuous learning that are key to elderly health. As other countries will face similar issues, further international interdisciplinary knowledge-building will be necessary to face the challenges of super-aging societies.

An Application of Deep Learning to Tactile Data for Object Recognition under Visual Guidance

Drawing inspiration from haptic exploration of objects by humans, the current work proposes a novel framework for robotic tactile object recognition, where visual information in the form of a set of visually interesting points is employed to guide the process of tactile data acquisition. Neuroscience research confirms the integration of cutaneous data as a response to surface changes sensed by humans with data from joints, muscles, and bones (kinesthetic cues) for object recognition. On the other hand, psychological studies demonstrate that humans tend to follow object contours to perceive their global shape, which leads to object recognition. In compliance with these findings, a series of contours are determined around a set of 24 virtual objects from which bimodal tactile data (kinesthetic and cutaneous) are obtained sequentially and by adaptively changing the size of the sensor surface according to the object geometry for each object. A virtual Force Sensing Resistor array (FSR) is employed to capture cutaneous cues. Two different methods for sequential data classification are then implemented using Convolutional Neural Networks (CNN) and conventional classifiers, including support vector machines and k-nearest neighbors. In the case of conventional classifiers, we exploit contourlet transformation to extract features from tactile images. In the case of CNN, two networks are trained for cutaneous and kinesthetic data and a novel hybrid decision-making strategy is proposed for object recognition. The proposed framework is tested both for contours determined blindly (randomly determined contours of objects) and contours determined using a model of visual attention. Trained classifiers are tested on 4560 new sequential tactile data and the CNN trained over tactile data from object contours selected by the model of visual attention yields an accuracy of 98.97% which is the highest accuracy among other implemented approaches.

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

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.

DNN-Based Assistant in Laparoscopic Computer-Aided Palpation

Tactile sensory input of surgeons is severely limited in minimally invasive surgery, therefore manual palpation cannot be performed for intraoperative tumor detection. Computer-aided palpation, in which tactile information is acquired by devices and relayed to the surgeon, is one solution for overcoming this limitation. An important design factor is the method by which the acquired information is fed back to the surgeon. However, currently there is no systematic method for achieving this aim, and it is possible that a badly implemented feedback mechanism could adversely affect the performance of the surgeon. In this study, we propose an assistance algorithm for intraoperative tumor detection in laparoscopic surgery. Our scenario is that the surgeon manipulates a sensor probe, makes a decision based on the feedback provided from the sensor, while simultaneously, the algorithm analyzes the time series of the sensor output. Thus, the algorithm assists the surgeon in making decisions by providing independent detection results. A deep neural network model with three hidden layers was used to analyze the sensor output. We propose methods to input the time series of the sensor output to the model for real-time analysis, and to determine the criterion for detection by the model. This study aims to validate the feasibility of the algorithm by using data acquired in our previous psychophysical experiment. There, novice participants were asked to detect a phantom of an early-stage gastric tumor through visual feedback from the tactile sensor. In addition to the analysis of the accuracy, signal detection theory was employed to assess the potential detection performance of the model. The detection performance was compared with that of human participants. We conducted two types of validation, and found that the detection performance of the model was not significantly different from that of the human participants if the data from a known user was included in the model construction. The result supports the feasibility of the proposed algorithm for detection assistance in computer-aided palpation.