Haptic Interface on Measured Data for Epidural Simulation

Author(s):  
Neil Vaughan ◽  
Venketesh N. Dubey ◽  
Michael Y. K. Wee ◽  
Richard Isaacs

This paper presents a haptic device with 3D computer graphics as part of a high fidelity medical epidural simulator development program. The haptic device is used as an input to move the needle in 3D, and also to generate force feedback to the user during insertion. A needle insertion trial was conducted on a porcine cadaver to obtain force data. The data generated from this trial was used to recreate the feeling of epidural insertion in the simulator. The interaction forces have been approximated to the resultant force obtained during the trial representing the force generated by the haptic device. The haptic device is interfaced with the 3D graphics for visualization. As the haptic stylus is moved, the needle moves on the screen and the depth of the needle tip indicates which tissue layer is being penetrated. Different forces are generated by the haptic device for each tissue layer as the epidural needle is inserted. As the needle enters the epidural space, the force drops to indicate loss of resistance.

Author(s):  
Neil Vaughan ◽  
Venketesh N. Dubey ◽  
Michael Y. K. Wee ◽  
Richard Isaacs

A volumetric graphics model of deformable human tissue with layers of varying stiffness was developed. The model uses spring-mass-damper to calculate haptic force feedback from various layers of tissue. A haptic epidural needle insertion simulation is developed with real-time tissue deformation when external forces are exerted. Voxelization is used to fill surface meshes with grids of spring-mass-damper assemblies. The modeled tissues include all the layers traversed during an epidural procedure, including skin, subcutaneous fat, Supraspinous and interspinous ligaments, ligamentum flavum and the epidural space. Tissue is modeled with volumetric information describing the stiffness and density of each layer. Spring-mass-damper modeling enables the calculation of compression and extension of springs between tissue masses, to simulate tissue stretching and relaxation movement. A haptic force feedback device is used to interact with the tissue model with a virtual needle. The resulting simulation gives a different feeling for each tissue layer. The haptic device allows the user to insert a needle though the modeled tissue layers feeling the various physical properties of each tissue layer during needle insertion. Tissues can be viewed in cross-section to see the progress and depth of the needle. Force feedback graphs were produced to compare the force from the operator’s thumb to the resultant force feedback from the device.


Author(s):  
Neil Vaughan ◽  
Venketesh N. Dubey ◽  
Michael Y. K. Wee ◽  
Richard Isaacs

The aim of this study was to measure changing pressures during Tuohy epidural needle insertions for obstetric parturients of various BMI. This has identified correlations between BMI and epidural pressure. Also we investigated links between BMI and the thicknesses and depths of ligaments and epidural space as measured from MRI and ultrasound scans. To date there have been no studies relating epidural pressure and ligament thickness changes with varying Body Mass Indices (BMI). Further goals following measurement of pressure differences between various BMI patients, were to allow a patient-specific epidural simulator to be developed, which has not been achieved before. The trial has also assessed the suitability of our in-house developed wireless pressure measurement device for use in-vivo. Previously we conducted needle insertion trial with porcine for validation of the measurement system. Results showed that for each group average pressures during insertion decrease as BMI increases. Pressure measurements obtained from the patients were matched to tissue thickness measurements from MRI and ultrasound scans. The mean Loss of Resistance (LOR) pressure in each group reduces as BMI increases. Variation in the shape of the pressure graphs was noticed between two epiduralists performing the procedure, suggesting each anaesthetist may have a signature graph shape. This is a new finding which offers potential use in epidural training and assessment. It can be seen that insertions performed by the first epiduralist have a higher pressure range than insertions performed by second epiduralist.


2009 ◽  
Vol 56 (3) ◽  
pp. 820-827 ◽  
Author(s):  
D. Tran ◽  
King-Wei Hor ◽  
A.A. Kamani ◽  
V.A. Lessoway ◽  
R.N. Rohling

2021 ◽  
pp. 1-63
Author(s):  
Jin Lixing ◽  
Duan Xingguang ◽  
Li Changsheng ◽  
Shi Qingxin ◽  
Wen Hao ◽  
...  

Abstract This paper presents a novel parallel architecture with seven active degrees of freedom (DOFs) for general-purpose haptic devices. The prime features of the proposed mechanism are partial decoupling, large dexterous working area, and fixed actuators. The detailed processes of design, modeling, and optimization are introduced and the performance is simulated. After that, a mechanical prototype is fabricated and tested. Results of the simulations and experiments reveal that the proposed mechanism possesses excellent performances on motion flexibility and force feedback. This paper aims to provide a remarkable solution of the general-purpose haptic device for teleoperation systems with uncertain mission in complex applications.


2021 ◽  
Author(s):  
Mine Sarac ◽  
Duke Loke ◽  
Max Evans ◽  
Olivia Chong ◽  
James Saunders ◽  
...  

2003 ◽  
Vol 99 (6) ◽  
pp. 1387-1390 ◽  
Author(s):  
Philipp Lirk ◽  
Christian Kolbitsch ◽  
Guenther Putz ◽  
Joshua Colvin ◽  
Hans Peter Colvin ◽  
...  

Background Cervical and high thoracic epidural anesthesia and analgesia have gained increasing importance in the treatment of painful conditions and as components of anesthetics for cardiac and breast surgery. In contrast to the hanging-drop technique, the loss-of-resistance technique is thought to rely on the penetration of the ligamentum flavum. However, the exact morphology of the ligamentum flavum at different vertebral levels remains controversial. Therefore, the aim of this study was to investigate the incidence and morphology of cervical and high thoracic ligamentum flavum mid-line gaps in embalmed cadavers. Methods Vertebral column specimens were obtained from 52 human cadavers. On each dissected level, ligamentum flavum mid-line gaps were recorded and evaluated with respect to shape and size. Results The following variations were encountered: complete fusion in the mid-line, mid-line fusion with a gap in the caudal part, mid-line gap, and mid-line gap with widened caudal end. The incidence of mid-line gaps at the following levels was: C3-C4: 66%, C4-C5: 58%, C5-C6: 74%, C6-C7: 64%, C7-T1: 51%, Th1-Th2: 21%, Th2-Th3: 11%, Th3-Th4: 4%, Th4-Th5: 2%, and Th5-Th6: 2%. The mean width of mid-line gaps was 1.0 +/- 0.3 mm. Conclusions In conclusion, the present study shows that gaps in the ligamenta flava are frequent at cervical and high thoracic levels but become rare at the T3/T4 level and below, such that one cannot always rely on the ligamentum flavum as a perceptible barrier to epidural needle placement at these levels.


2018 ◽  
Vol 67 (12) ◽  
pp. 922-930 ◽  
Author(s):  
H. Bomberg ◽  
N. Paquet ◽  
A. Huth ◽  
S. Wagenpfeil ◽  
P. Kessler ◽  
...  

Author(s):  
Yiyun Wang ◽  
Hongbing Li

In lumbar puncture surgeries, force and position information throughout the insertion procedure is vital for needle tip localization, because it reflects different tissue properties. Especially in pediatric cases, the changes are always insignificant for surgeons to sense the crucial feeling of loss of resistance. In this study, a robot system is developed to tackle the major clinical difficulties. Four different control algorithms with intention recognition ability are applied on a novel lumbar puncture robot system for better human–robot cooperation. Specific penetration detection based on force and position derivatives captures the feeling of loss of resistance, which is deemed crucial for needle tip location. Kinematic and actuation modeling provides a clear description of the hardware setup. The control algorithm experiment compares the human–robot cooperation performance of proposed algorithms. The experiment also dictates the clear role of designed penetration detection criteria in capturing the penetration, improving the success rate, and ensuring operational safety.


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