Needle Insertion Task Research Articles

Cutaneous Force Feedback as a Sensory Subtraction Technique in Haptics.

A novel sensory substitution technique is presented. Kinesthetic and cutaneous force feedback are substituted by cutaneous feedback (CF) only, provided by two wearable devices able to apply forces to the index finger and the thumb, while holding a handle during a teleoperation task. The force pattern, fed back to the user while using the cutaneous devices, is similar, in terms of intensity and area of application, to the cutaneous force pattern applied to the finger pad while interacting with a haptic device providing both cutaneous and kinesthetic force feedback. The pattern generated using the cutaneous devices can be thought as a subtraction between the complete haptic feedback (HF) and the kinesthetic part of it. For this reason, we refer to this approach as sensory subtraction instead of sensory substitution. A needle insertion scenario is considered to validate the approach. The haptic device is connected to a virtual environment simulating a needle insertion task. Experiments show that the perception of inserting a needle using the cutaneous-only force feedback is nearly indistinguishable from the one felt by the user while using both cutaneous and kinesthetic feedback. As most of the sensory substitution approaches, the proposed sensory subtraction technique also has the advantage of not suffering from stability issues of teleoperation systems due, for instance, to communication delays. Moreover, experiments show that the sensory subtraction technique outperforms sensory substitution with more conventional visual feedback (VF).

Haptic Sensitivity in Compliance Evaluation in a Tool-Wielding Paradigm

This paper describes a methodology for establishing standardized tests of haptic sensitivity in a tool-wielding paradigm. A haptic-needle was developed to study compliance differentiation in a needle-insertion task, using a psychophysics experimental protocol. The relationship of applied force and position as a function of perceived tissue compliance was obtained from the recorded data. The Just-Noticeable-Difference (JND) for tissue compliance discrimination with the haptic needle was calculated. Results showed that the JND increased as compliance of the tissue increased. Compliance differentiation was easier when the layers of tissue were more different in compliance. These common trends suggest that the proposed methodology is valid and the haptic performance of human subjects can be quantified.

Perception and Action in Teleoperated Needle Insertion.

We studied the effect of delay on perception and action in contact with a force field that emulates elastic soft tissue with a rigid nonlinear boundary. Such a field is similar to forces exerted on a needle during teleoperated needle insertion. We found that delay causes motor underestimation of the stiffness of this nonlinear soft tissue, without perceptual change. These experimental results are supported by simulation of a simplified mechanical model of the arm and neural controller, and a model for perception of stiffness, which is based on regression in the force-position space. In addition, we show that changing the gain of the teleoperation channel cancels the motor effect of delay without adding perceptual distortion. We conclude that it is possible to achieve perceptual and motor transparency in virtual one-dimensional remote needle insertion task.

Influences of haptic communication on a shared manual task

With the advent of new haptic feedback devices, researchers are giving serious consideration to the incorporation of haptic communication in collaborative virtual environments. For instance, haptic interactions based tools can be used for medical and related education whereby students can train in minimal invasive surgery using virtual reality before approaching human subjects. To design virtual environments that support haptic communication, a deeper understanding of humans′ haptic interactions is required. In this paper, human′s haptic collaboration is investigated. A collaborative virtual environment was designed to support performing a shared manual task. To evaluate this system, 60 medical students participated to an experimental study. Participants were asked to perform in dyads a needle insertion task after a training period. Results show that compared to conventional training methods, a visual-haptic training improves user′s collaborative performance. In addition, we found that haptic interaction influences the partners′ verbal communication when sharing haptic information. This indicates that the haptic communication training changes the nature of the users′ mental representations. Finally, we found that haptic interactions increased the sense of copresence in the virtual environment: haptic communication facilitates users′ collaboration in a shared manual task within a shared virtual environment. Design implications for including haptic communication in virtual environments are outlined.

Haptic sensitivity in needle insertion: the effects of training and visual aid

This paper describes an experiment conducted to measure haptic sensitivity and the effects of haptic training with and without visual aid. The protocol for haptic training consisted of a needle insertion task using dual-layer silicon samples. A visual aid was provided as a multimodal cue for the haptic perception task. Results showed that for a group of novices (subjects with no previous experience in needle insertion), training with a visual aid resulted in a longer time to task completion, and a greater applied force, during post-training tests. This suggests that haptic perception is easily overshadowed, and may be completely replaced, by visual feedback. Therefore, haptic skills must be trained differently from visuomotor skills.

Efficacy of image-guided action is controlled by perception

to be published in the Journal of Vision Researchers on human perception have devised a number of methods for measuring perceived location and using it to assess perceptually guided action. Such work has primarily been performed in space accessible by reaching and walking. Here we use the same approach to assess perceptually guided action in very near space, specifically, in the applied context of ultrasound-guided surgical manipulation. Our approach measured the ultrasound user’s perception of the location of a target independently from assessing the action employed to reach it. Experiments were conducted with the Sonic Flashlight (SF), a visualization device that creates a virtual in situ image, and conventional ultrasound (CUS), which displays the image on a screen displaced from the target. Two studies determined subjects’ perception of target location with a triangulation-by-pointing task. Depth perception with the SF was comparable to direct vision, while the CUS caused considerable underestimation of target depth. Binocular depth information in the SF was shown to significantly contribute to its superiority. A third experiment tested subjects in an ultrasound-guided needle insertion task. With direct visualization of the target, subjects performed insertions faster and more accurately by using the SF rather than CUS. Furthermore, the trajectory analysis showed that insertions with the SF generally went directly to the target along the desired path, while the CUS led to an arc-shaped deviation from the ideal path, as predicted by the previously measured underestimation of target depth. Ongoing research is further examining the time-course of learning with the two devices, measuring precise trajectories for needle insertion. This work extends the demonstration of the perception/action linkage to near space and provides a very practical application for such research. In particular, different image methods, which lead to different percepts, will lead to actions with differential efficacy.

Perception and Action in Simulated Telesurgery.

We studied the effect of delay on perception and action in contact with a force field that emulates elastic soft tissue with a specific rigid nonlinear boundary. Such field is similar to forces exerted on a needle during teleoperated needle insertion tasks. We found that a nonlinear boundary region causes both psychometric and motor overestimation of stiffness, and that delay causes motor but not psychometric underestimation of the stiffness of this nonlinear soft tissue. In addition we show that changing the teleoperation channel gain reduces and can even cancel the motor effect of delay.

Vascular Access: Comparison of US Guidance with the Sonic Flashlight and Conventional US in Phantoms

To prospectively evaluate whether ultrasonography (US)-guided vascular access can be learned and performed faster with the sonic flashlight than with conventional US and to demonstrate sonic flashlight-guided vascular access in a cadaver. Institutional review board approval and oral and written informed consent were obtained. The sonic flashlight replaces the standard US monitor with a real-time US image that appears to float beneath the skin and is displayed where it is scanned. In studies 1 and 2, participants performed sonic flashlight-guided needle insertion tasks in vascular phantoms. In study 1, 16 participants (nine women, seven men) with no US experience performed 60 simulated vascular access trials with sonic flashlight or conventional US guidance. With analysis of variance (ANOVA) and power-curve fitting, improvement with practice rate and mean differences between techniques and tasks were examined. In study 2, 14 female nurses (mean age, 50.1 years) proficient with conventional US performed simulated vascular access trials on three tasks with the sonic flashlight and conventional US. With random assignment, half the participants used the sonic flashlight first and half used conventional US first. Mean performance with each technique and that with each task were compared by using ANOVA. In study 3, feasibility of sonic flashlight guidance for access to internal jugular and basilic veins was demonstrated in a cadaver. For study 1, learning rates (ie, decrease in access time over trials) did not differ for vascular access with sonic flashlight and conventional US. Overall, participants achieved faster vascular access times with sonic flashlight guidance (P < .007). In study 2, participants performed procedures faster overall with the sonic flashlight (P < .02) and found the sonic flashlight easier to use. In study 3, sonic flashlight-guided vascular access was gained in the cadaver. Learning and performance of vascular access were significantly faster with the sonic flashlight than with conventional US, and vascular access could be gained in a cadaver; the sonic flashlight is ready for clinical trials.

Psychophysical Evaluation of In-Situ Ultrasound Visualization

We present a novel psychophysical method for evaluating ultrasonography based on Real-Time Tomographic Reflection (RTTR), in comparison to Conventional Ultrasound (CUS). The method measures the user's perception of the location of an ultrasound-imaged target independently from assessing the action employed to reach it. Three experiments were conducted with the Sonic Flashlight (SF), an RTTR device, and CUS. The first two experiments determined subjects' perception of target location with a triangulation-by-pointing task. Depth perception with the SF was comparable to direct vision, while CUS caused considerable underestimation of target depth. Binocular depth information in the SF was shown to significantly contribute to its superiority. The third experiment tested subjects in an ultrasound-guided needle insertion task. Because the SF provides visualization of the target at its actual location, subjects performed insertions faster and more accurately by using the SF rather than CUS. Furthermore, the trajectory analysis showed that insertions with the SF generally went directly to the target along the desired path, while CUS often led to a large deviation from the correct path consistent with the observed underestimation of target depth. These findings lend great promise to the use of RTTR-based imaging in clinical practice and provide precise means of assessing efficacy.

SU‐FF‐T‐03: Design and Quantitative Analysis of a Novel Brachytherapy Robot

Purpose: To design a novel brachytherapy robot and compare its static manipulability characteristics to two well‐known robotic manipulators: the Puma560 and the Stanford Arm. Method and Materials: The open‐source 3‐D Slicer program was used to model the prostate from clinical CT data. Workspace dimensions were determined and applied to the design of a new robot. The robot was modeled mathematically using the modified Denavit and Hartenberg representation of robotic manipulators. The static force and velocity manipulability ellipsoids were calculated for all three robots in several different poses using the Robot Toolbox for Matlab® (P.I. Corke, CSIRO, Australia, 2002). The force and velocity transformation ratios were computed and compared for similar poses. A small transformation ratio indicates the robot is sensitive to errors in control tasks, but not well‐suited for actuation tasks. The manipulability measure was also calculated. The manipulability measure is a quantitation of the range‐of‐motion of a robot in a given pose. Results: The calculations show the brachytherapy robot can implant a needle with a good balance of force and velocity with a high percentage of the maximum values. The Puma560 is relatively balanced, however most transformation ratios are less than 10% of the maximum. The Stanford Arm is not well balanced in both configurations studied. The Stanford Arm's transformation ratios are also relatively low percentages of the maximum. The manipulability measures for the brachytherapy robot were between 1.6 and 5 times higher than the other robots. Conclusion: Several robots have been developed for brachytherapy implantations. None have provided quantitative comparisons to other robots. Here, static manipulability calculations compare different robots with a specific pose (initial task‐oriented configuration). Our brachytherapy robot has balanced transformation ratios and also shows a high degree of manipulability. Initial calculations show that this robot is well configured for needle insertion tasks.

How to Approach Medical Negligence in Order to Avoid it

Conventional needle insertion training relies on medical dummies that simulate surface anatomy and internal structures such as veins or arteries. These dummies offer an interesting space to augment with useful information to assist training practices, namely, internal anatomical structures (subclavian artery and vein, internal jugular vein and carotid artery) along with target point, desired inclination, position and orientation of the needle. However, limited research has been conducted on Optical See-Through Augmented Reality (OST-AR) interfaces for training needle insertion, especially for central venous catheterization (CVC). In this work we introduce PIÑATA, an interactive tool to explore the benefits of OST-AR in CVC training using a dummy of the upper torso and neck; andexplore if PIÑATA complements conventional training practices.. Our design contribution also describes the observation and co-design sessions used to collect user requirements, usability aspects and user preferences. This was followed by a comparative study with 18 participants - attending specialists and medical residents - that performed needle insertion tasks for CVC with PIÑATAand the conventional training system. The performance was objectively measured by task completion time and number of needle insertion errors. A correlation was found between the task completion time in the two training methods, suggesting the concurrent validity of our OST-AR tool. An inherent difference in the task completion time (p =0.040) and in the number of errors (p = 0.036) between novices and experts proved the construct validity of the new tool. The qualitative answers of the participants also suggest its face and content validity, a high acceptability rate and a medium perceived workload. Finally, the result of semi-structured interviews with these 18 participants revealed that 14 of them considered that PIÑATA can complement the conventional training system, especially due to the visibility of the vessels inside the simulator. 13 agreed that OST-AR adoption in these scenarios is likely, particularly during early stages of training. Integration with ultrasound information was highlighted as necessary future work. In sum, the overall results show that the OST-AR tool proposed can complement the conventional training of CVC.