Needle Steering for Robot-Assisted Insertion into Soft Tissue:A Survey

Needle insertion is a common surgical procedure used in diagnosis and treatment.The needle steering technologies make continuous developments in theoretical and practical aspects along with the in-depth research on needle insertion.It is necessary to summarize and analyze the existing results to promote the future development of theories and applications of needle insertion.Thus,a survey of the state of the art of research is presented on algorithms of needle steering techniques,the surgical robots and devices.Based on the analysis of the needle insertion procedure,the concept of needle steering is defined as a kinematics problem,which is to place the needle at the target and avoid the obstacles.The needle steering techniques,including the artificial potential field method and the nonholonomic model,are introduced to control the needles for improving the accuracy.Based on the quasi-static thinking,the virtual spring model and the cantilever-beam model are developed to calculate the amount of needle deflection and generate the needle path.The phantoms instead of the real tissue are used to verify the models mentioned in most of the experimentations.For the desired needle trajectories,the image-guided robotic devices and some novel needles are presented to achieve the needle steering.Finally,the challenges are provided involving the controllability of the long flexible needle and the properties of soft tissue.The results and investigations can be used for further study on the precision and accuracy of needle insertion.

Comparison of Gluteal Muscle Intramuscular Injection Sites of Japanese Healthy Subjects: Considerations for Optimal Insertion of Injection Needle Length

Long Acting Injectable (LAI) medications for patients with schizophrenia is commonly administered to relieve their symptoms. Through shared decision-making and clinical evidence-based, psychiatrists should systematically offer LAIs to all patients requiring long-term antipsychotic treatment as a first-line treatment. Gluteal intramuscular (IM) injection requires accurate insertion of needles into the specific muscle area, often the outer upper quadrant of the buttocks, in order to achieve the required blood concentration. The purposes of this study were to compare the “Distance from the Epidermis to the Under-Fascia (DEUF)” and “Distance from the Epidermis to the Iliac Bone (DEB)” of the buttocks IM injection sites at the dorsogluteal and ventrogluteal sites among healthy Japanese volunteer subjects, and to identify the optimal insertion injection needle length. The DEUF and DEB at the gluteal regions were measured by ultrasonography. Welch’s one-way analysis of variance was used to compare the DEUF and the DEB at the gluteal IM injection regions. There was no statistically significant difference observed between the right and left mean values of DEUF for Hochstetter and Clark’s point at the ventrogluteal sites, and the Four and Three-way split or Double Cross point at the dorsogluteal sites. However in the DEB, the Hochstetter’s point (P < 0.01) at ventrogluteal site on the right side, and Clark’s point (P < 0.05) were significantly shorter than the Double Cross point at dorsogluteal sites (F = 4.38). The left buttocks Hochstetter’s point was significantly shorter than the Double Cross point (F = 4.38, P < 0.01). These results, however, did not establish a statistically significant difference in the DEUF among injection sites. It was considered that the difference in the DEB depended on muscle volume and thickness in the gluteal injection sites.

Sensitivity of Influential Factors on Needle Insertion Experiments:A Quantitative Analysis on Phantom Deformations and Needle Deflections

High repeatability of needle insertion experiments is essential to the needle-phantom interaction model validation.However,the influential factors governing the accuracy of the phantom and needle deformations have not been systematically studied.In this paper,the impact of influential factors,including phantom characteristic represented by the ratio of DMSO and thawing time(TT),needle properties represented by needle external diameter(NED)and operating factors such as needle insertion velocity(IV),insertion positions(IP)and repeated insertion times(RITs)are analyzed by orthogonal experiment design.The range calculation shows the most sensitive parameters to phantom deformations are RITs,IV and DMSO while the most sensitive parameters to needle deflection are DMSO,TT and NED.By variance analysis,the significant factors on maximum tissue deformation(MTD)are IV,followed by RITs,DMSO and IP.And NED and TT have nearly no significant impact on MTD.The significant sequence on maximum needle deflection(MND)is as follows:DMSO,TT and NED.Results show that,among all impacting factors,phantom deformation is susceptible to both material properties and operative factors while the needle deflection is more susceptible to material properties of the phantom,which can help researchers in related fields to conduct experiments in a more precise manner and better understand the needle-phantom interaction mechanism.

Method with repeated extraction-insertion cycles to im prove the needle insertion accuracy

In order to improve the effectiveness of percutaneous diagnosis and therapies, the needle insertion into the deforming soft and inhomogenous tissue should be accurate. In this study a needle with 6 degrees of freedom force/torque sensor is used to find the relationship between the pathway＇s length and the force. Our experiments show that the method with repeated extraction-insertion cy- cles can make the needle approach the target as much as possible. Meanwhile a method to obtain the appropriaterepeated extraction-insertion cycles is given to drive the needle to execute the repeat- ed cycles efficiently. Experiments and discussions were conducted to preliminarily validate the meth- od.

Soft Tissue Deformation Modeling in the Procedure of Needle Insertion:A Kriging‑Based Method

The simulation and planning system(SPS)requires accurate and real-time feedback regarding the deformation of soft tissues during the needle insertion procedure.Traditional mechanical-based models such as the finite element method(FEM)are widely used to compute the deformations of soft tissue.However,it is difficult for the FEM or other methods to find a balance between an acceptable image fidelity and real-time deformation feedback due to their complex material properties,geometries and interaction mechanisms.In this paper,a Kriging-based method is applied to model the soft tissue deformation to strike a balance between the accuracy and efficiency of deformation feedback.Four combinations of regression and correlation functions are compared regarding their ability to predict the maximum deformations of ten characteristic markers at a fixed insertion depth.The results suggest that a first order regression function with Gaussian correlation functions can best fit the results of the ground truth.The functional response of the Kriging-based method is utilized to model the dynamic deformations of markers at a series of needle insertion depths.The feasibility of the method is verified by investigating the adaptation to step variations.Compared with the ground truth of the finite element(FE)results,the maximum residual is less than 0.92 mm in the Y direction and 0.31 mm in the X direction.The results suggest that the Kriging metamodel provides real-time deformation feedback for a target and an obstacle to a SPS.

Fuzzy control method to minimize the needle deflection during needle insertion therapy

A fuzzy control algorithm is adopted to help the needle hit the target more accurately. The experimental setup for the needle insertion is built up to validate the algorithm. How the forces dur- ing the insertion make the needle deflect away from the planned path is given, and the normal meth- od correcting the deflection is obtained accordingly. Because the normal method cannot perform well for correction, a fuzzy controller is established. The input module, output module, fuzzification module, defuzzification module and inference engine for the controller are given respectively accord- ing to the fuzzy theory. Our experimental results show that the fuzzy controlling system presenting in the paper can better eliminate the deflection.

Dynamic Soft Tissue Deformation Estimation Based on Energy Analysis

The needle placement accuracy of millimeters is required in many needle-based surgeries. The tissue deformation, especially that occurring on the surface of organ tissue, affects the needle-targeting accuracy of both manual and robotic needle insertions. It is necessary to understand the mechanism of tissue deformation during needle insertion into soft tissue. In this paper, soft tissue surface deformation is investigated on the basis of continuum mechanics, where a geometry model is presented to quantitatively approximate the volume of tissue deformation. The energy-based method is presented to the dynamic process of needle insertion into soft tissue based on continuum mechanics, and the volume of the cone is exploited to quantitatively approximate the deformation on the surface of soft tissue. The external work is converted into potential, kinetic, dissipated, and strain energies during the dynamic rigid needle-tissue interactive process. The needle insertion experimental setup, consisting of a linear actuator, force sensor, needle, tissue container, and a light, is constructed while an image-based method for measuring the depth and radius of the soft tissue surface deformations is introduced to obtain the experimental data. The relationship between the changed volume of tissue deformation and the insertion parameters is created based on the law of conservation of energy, with the volume of tissue deformation having been obtained using image-based measurements. The experiments are performed on phantom specimens, and an energy-based analytical fitted model is presented to estimate the volume of tissue deformation. The experimental results show that the energy-based analytical fitted model can predict the volume of soft tissue deformation, and the root mean squared errors of the fitting model and experimental data are 0.61 and 0.25 at the velocities 2.50 mm/s and 5.00 mm/s. The estimating parameters of the soft tissue surface deformations are proven to be useful for compensating the needle-targeting error in the rigid needle insertion procedure, especially for percutaneous needle insertion into organs.

A medical robot for needle placement therapy in liver cancer

Hepatocellular carcinoma (HCC) is the second most common malignancy in China.As microwave ablation (MWA) is an effective method for liver cancer,a robotic surgical system with ultrasound-directed was designed to assist surgeons on positioning the needles.This robotic system includes a surgical robot with 5 degrees of freedom,a workstation for path-planning and image processing,a conventional 2D ultrasound device,and an electromagnetic (EM) tracking system.Surgery space,clinical operation requirements and optimal mechanical structure are the key factors to be considered in designing a medical robot suitable for use by surgeons.Based on the mechanics of the needle placement robot,we have conducted detailed kinematic analysis,including a combined numerical algorithm and coordinate mapping.Finally,the feasibility of the needle placement robot has been validated by experiment.

A study to investigate needle insertion at Shenshu(BL23) to puncture psoas major muscle

OBJECTIVE： It is unknown whether the psoas major muscle, thought to be a key muscle for treatment of lower back pain, can be punctured at Shenshu（BL23）.METHODS： Twelve dissected specimens were used for studying the needling pathway of BL23 by perpendicularly inserting the depth-measuring blade of a vernier caliper at BL23. Dimensions of psoas muscle were measured. Correlation studies were conducted. In addition, our samples were grouped by gender and underlying medical conditions for analysis.RESULTS： Half（50%） of the needle insertions successfully punctured psoas muscle. The mean depth of needle insertion to puncture psoas muscle（D_（min）） in the group with short-term underlying medical conditions was 38.0 mm（interquartile range 29.0–51.8 mm）, approximately 6 mm deeper than 32.0（29.3–42.5） mm in the group with long-term health problems（P = 0.041）. The cross-sectional area（CSA） of psoas muscle in the former group was on average approximately 1.5 times that of the latter group（P = 0.04）. When the data were analysed by gender, the thickness of psoas muscle in the male group was 19.0（6.5–24.0） mm compared to 19.5（5.8–34.8） mm in the female group（P = 0.02）. The age in the female group（P = 0.04） and the body length of the total group（P = 0.04） negatively correlated to D_（min）.CONCLUSION： Needle insertion at BL23 might be able to puncture psoas muscle. Differences in the CSA of psoas muscle and D_（min） were observed in groups with short-term and long-term underlying medical conditions.