Needle Tip Force Research Articles

Haptic Teleoperation of Flexible Needles Combining 3D Ultrasound Guidance and Needle Tip Force Feedback

We present a haptic teleoperation system capable of steering flexible needles under ultrasound imaging toward a target. With respect to similar works, this approach enables intuitive control of the needle motion while providing the user with 3D navigation and needle tip cutting force using a combination of kinesthetic and vibrotactile haptic feedback. The needle is tracked during the insertion using a 3D ultrasound probe. A friction estimation algorithm extracts salient information about the cutting force at the needle tip from a force sensor placed at the needle base. A grounded haptic interface enables natural 6-DoF control of the needle motion while providing kinesthetic feedback, and a wearable cutaneous interface on the forearm provides distributed vibrotactile sensations. We carried out a human subject study to validate the insertion system in a gelatine phantom and compare seven different feedback techniques. The best performance was registered when providing navigation cues through kinesthetic feedback and needle tip cutting force through cutaneous vibrotactile feedback. In this modality, results showed an 87% accuracy improvement with respect to providing no haptic feedback at all.

Ultrasound-guided Needle nerve contact positions detection in Regional Anaesthesia using Needle tip force and Opening injection pressure

Ultrasound imaging guidance has been widely used in peripheral nerve block to guide the anaesthetist to insert the needle and observe injection fluid diffusion. However, needle-nerve contact(NNC) positions visualization is difficult to achieve because of requirement of high image solution and expert. To better guide the anaesthetist to predict the distance from needle to nerve and reduce the needle trauma, we attempted to use Needle tip force(NTF) and Opening injection pressure (OIP) to identify the NNC positions under ultrasound guidance. The relationship between OIP and NNC, NTF and NNC, NTF and OIP is unclear now, and we conducted a prospective, observational study to define the relationship. In this study, we designed a multi-function block needle and built a real-time NTF and OIP measurement which could trace and record NTF and OIP data in the simulator sciatic nerve. NNC positions were divided into three distinct NNC positions: Pre-NNC, First-NNC, Forceful-NNC using ultrasound guidance image. We statistically analysis NTF, OIP in the three NNC positions, and the results indicate the NTF differentiate in three NNC positions(p<0.001), OIP differentiate as well (p<0.001) and the NTF has a highly positive with the OIP in the same NNC positions with Pearson correlation 0.62.

Needle-tissue interaction force study during simulated regional anaesthesia

Needle insertion usually performed with the aid of an Ultrasound (US) image in the regional anaesthesia. Getting the position of the needle tip from US requires the technical expertise and skilled anaesthetist. To detect where the needle tip is around the nerve during the needle insertion, a modified block needle attached with a force sensor is used to feedback the amount of counter force from the needle tip. This paper is to investigate whether needle force under ultrasound guidance can guide anaesthesiologists in identifying the relative position of the needle tip and nerve The goal of our research was to use the visual needle tip force to guide the anaesthetist to detect the relative positions between the needle tip and nerve.

Spatio-temporal deep learning models for tip force estimation during needle insertion

PurposePrecise placement of needles is a challenge in a number of clinical applications such as brachytherapy or biopsy. Forces acting at the needle cause tissue deformation and needle deflection which in turn may lead to misplacement or injury. Hence, a number of approaches to estimate the forces at the needle have been proposed. Yet, integrating sensors into the needle tip is challenging and a careful calibration is required to obtain good force estimates.MethodsWe describe a fiber-optic needle tip force sensor design using a single OCT fiber for measurement. The fiber images the deformation of an epoxy layer placed below the needle tip which results in a stream of 1D depth profiles. We study different deep learning approaches to facilitate calibration between this spatio-temporal image data and the related forces. In particular, we propose a novel convGRU-CNN architecture for simultaneous spatial and temporal data processing.ResultsThe needle can be adapted to different operating ranges by changing the stiffness of the epoxy layer. Likewise, calibration can be adapted by training the deep learning models. Our novel convGRU-CNN architecture results in the lowest mean absolute error of 1.59 pm 1.3,hbox {mN} and a cross-correlation coefficient of 0.9997 and clearly outperforms the other methods. Ex vivo experiments in human prostate tissue demonstrate the needle’s application.ConclusionsOur OCT-based fiber-optic sensor presents a viable alternative for needle tip force estimation. The results indicate that the rich spatio-temporal information included in the stream of images showing the deformation throughout the epoxy layer can be effectively used by deep learning models. Particularly, we demonstrate that the convGRU-CNN architecture performs favorably, making it a promising approach for other spatio-temporal learning problems.

&lt;italic&gt;In-Vivo&lt;/italic&gt; Tissue Identification on Mice Using a Fiber Optical Tip Force Sensing Needle

This paper presents in-vivo tissue identification on mice by our recently developed novel fiber optical tip force sensing needle. The needle can directly measure the axial force required to penetrate a tissue at its tip, which can then be used for in-vivo identification of tissues. Both ex-vivo and in-vivo tissue experiments were carried out on 32 mice. Ex-vivo tissue insertions were conducted on dead mice to study the influence of time of death on needle tip force, body temperature change, and the results of tissue identification. The in-vivo experiments focused on the difference in tissue identification from the ex-vivo experiments. In addition, a tip penetration force database of mouse tissues was established through dissected mice within one minute of death. By means of this database, experiments for tissue identification were carried out. Results show that the tip force sensing needle has the capacity to identify the organs during needle insertions.

Estimation of the friction force during the needle insertion using the disturbance observer and the recursive least square

Needle insertion can be performed with the aid of an ultrasound (US) image. Detecting the position of a needle in a US image requires considerable technical expertise. To detect whether the needle has reached the target, the physician usually relies on physically sensing the amount of force being fed back from the tip of the needle to their fingertip. The goal of our research was to develop a force visualization system to assist physicians by providing them with a visual representation of the needle tip force. In this paper, we elucidated the characteristics of the force during the needle insertion, and designed the friction force estimation method. Needle tip force is difficult to estimate directly. The total insertion force acting on the needle was defined by adding the needle tip force to the friction force of the needle surface. Therefore, we proposed a method of estimating the change in the friction force by measuring the total insertion force during needle insertion using recursive least square method and a disturbance observer. The needle tip and friction forces were modeled on the basis of the results of in vitro experiments used pork back ribs. The experiments performed using the coaxial needle. This needle could measure the total insertion force and the needle tip force separately in real time. The validity of the designed estimator was evaluated by using the force values obtained by using a coaxial needle. As a result, the estimated friction force and measured friction force were found to be qualitatively consistent. However, a slight error was observed.

Coaxial Needle Insertion Assistant With Enhanced Force Feedback

Many medical procedures involving needle insertion into soft tissues, such as anesthesia, biopsy, brachytherapy, and placement of electrodes, are performed without image guidance. In such procedures, haptic detection of changing tissue properties at different depths during needle insertion is important for needle localization and detection of subsurface structures. However, changes in tissue mechanical properties deep inside the tissue are difficult for human operators to sense, because the relatively large friction force between the needle shaft and the surrounding tissue masks the smaller tip forces. A novel robotic coaxial needle insertion assistant, which enhances operator force perception, is presented. This one-degree-of-freedom cable-driven robot provides to the operator a scaled version of the force applied by the needle tip to the tissue, using a novel design and sensors that separate the needle tip force from the shaft friction force. The ability of human operators to use the robot to detect membranes embedded in artificial soft tissue was tested under the conditions of 1) tip force and shaft force feedback, and 2) tip force only feedback. The ratio of successful to unsuccessful membrane detections was significantly higher (up to 50%) when only the needle tip force was provided to the user.

Novel needle cutting edge geometry for end‐cut biopsy

To introduce and determine the biopsy length performance of the novel enhanced cutting edge (ECE) needle tip design, which contains high inclination angles that allow for more efficient tissue cutting. ECE and regular two-plane symmetric needle tip's biopsy performance and cutting force are compared over a series of needle insertion experiments into bovine liver under varying levels of internal needle vacuum. An earlier developed needle tip force model is also applied. From these experiments and force model, the effect of needle tip geometry and vacuum on biopsy performance and force is studied. Biopsy sample length is on average 22%, 30%, and 49% longer for ECE needles compared to that of regular needles for the internal pressures of 0, -33.9, and -67.7 kPa, respectively. For ECE needles the vacuum level of -67.7 kPa produces on average biopsy lengths that are 41%, 31%, 29%, 45%, and 42% longer compared to no vacuum for two-plane needle tip bevel angles of 10°, 15°, 20°, 25°, and 30°, respectively. The force results show the ECE needle can be inserted with less initial insertion force than the regular two-plane needle for needles where the needle tip is fully contacting the tissue upon insertion. Vacuum is also showed to help lower insertion forces. The novel ECE needle tip design outperforms the regular two-plane symmetric needle by yielding longer biopsy samples and lower insertion forces, thereby demonstrating the benefits of needle geometries that contain higher inclination angles. The use of vacuum further improves the ECE needle tip biopsy sample length and lowers insertion forces.