Investigating the needle dynamic response during insertion into soft tissue

2009 ◽  
Vol 224 (4) ◽  
pp. 531-540 ◽  
Author(s):  
T Alja'afreh
Keyword(s):  
Soft Tissue ◽  
Ex Vivo ◽  
Surgical Techniques ◽  
Needle Insertion ◽  
Limiting Factor ◽  
Minimally Invasive Surgical ◽  
Soft Tissue Motion ◽  
Insertion Process ◽  
Tissue Motion

This paper investigates the effect of the needle velocity on soft-tissue motion ex vivo and in vivo. In many needle-based intervention procedures, which are common minimally invasive surgical techniques, the needle can be assumed to be rigid and the tissue deforms and displaces considerably as the needle moves forwards to its target. This paper presents an energy-based fracture mechanics approach to show that the increasing needle velocity can reduce tissue motion during the insertion process. The main feature of this paper is that it extends the proposed approach to model the insertion dynamics, whereas most of the literature treats needle insertion as a quasi-static process. Ex-vivo test results on lamb heart samples show that the force required to initiate penetration decreases with increasing needle velocity up to a critical velocity, above which the rate-independent penetration force of the underlying tissue becomes the limiting factor. In-vivo tests show that increased needle velocity results in reduced force and displacement for needle insertion into the heart. Results indicate that automated insertion could substantially improve performance in some applications.

A Six-Degree-of-Freedom Acoustic Transducer for Rotation and Translation Measurements Across the Knee

1990 ◽  
Vol 112 (4) ◽  
pp. 371-378 ◽  
Author(s):  
T. P. Quinn ◽  
C. D. Mote
Keyword(s):  
Soft Tissue ◽  
External Rotation ◽  
Worst Case ◽  
Mechanical Coupling ◽  
Acoustic Transducer ◽  
Transducer Design ◽  
Cadaver Specimen ◽  
Soft Tissue Motion ◽  
Tissue Motion

An acoustic transducer design to measure the relative translations and rotations across the knee with no mechanical coupling between the tibia and femur is presented. Platforms attached to femoral and tibial tracking fixtures hold acoustic sources and receivers, respectively. The distance from each source to each receiver is measured by the acoustic transit time and the translations and rotations across the knee joint are computed. For rotations less than 30 deg around the expected operating position, the resolution of the transducer is 0.3 deg; for translations less than 1.5 cm around the expected operating position, the resolution is 0.03 cm. Theoretical error analysis using a Monte Carlo method shows that the uncertainty in the measurement depends on the relative position of the sources and receivers. The analysis predicts the worst case resolution of the transducer as 0.09 cm in translation and 0.6 deg in rotation when the receiver platform is translated 8.0 cm parallel to the source platform. The transducer and fixturing system are demonstrated on a cadaver specimen for applied anterior force and applied internal-external rotation. Errors due to (soft tissue) motion of the transducer relative to the bone during in vivo measurements are assessed on the cadaver specimen. For internal-external rotation the error due to soft tissue motion is a maximum of 0.5 cm in translation and 1.8 deg in rotation. For applied anterior force the error due to soft tissue motion is a maximum of 0.16 cm in translation and 2.7 deg in rotation.

Using MR Imaging and X-Ray Fluoroscopy to Quantify the Effects of Soft-Tissue Artifact on Measurement of Knee-Joint Kinematics

2009 ◽  
Author(s):  
Massoud Akbarshahi ◽  
Justin W. Fernandez ◽  
Anthony Schache ◽  
Richard Baker ◽  
Marcus G. Pandy
Keyword(s):  
Soft Tissue ◽  
Knee Joint ◽  
Soft Tissues ◽  
Surgical Techniques ◽  
Joint Kinematics ◽  
Segmental Motion ◽  
Coordinate Systems ◽  
Knee Joint Kinematics ◽  
Soft Tissue Artifact

The ability to accurately measure joint kinematics in vivo is of critical importance to researchers in the field of biomechanics [1]. Applications range from the quantitative evaluation of different surgical techniques, treatment methods and/or implant designs, to the development of computer-based models capable of simulating normal and pathological musculoskeletal conditions [1,2]. Currently, non-invasive marker-based three dimensional (3D) motion analysis is the most commonly used method for quantitative assessment of normal and pathological locomotion. The accuracy of this technique is influenced by movement of the soft tissues relative to the underlying bones, which causes inaccuracies in the determination of segmental anatomical coordinate systems and tracking of segmental motion. The purpose of this study was to quantify the errors in the measurement of knee-joint kinematics due solely to soft-tissue artifact (STA) in healthy subjects. To facilitate valid inter-subject comparisons of the kinematic data, relevant anatomical coordinate systems were defined using 3D bone models generated from magnetic resonance imaging (MRI).

Activity of MK1775, a selective Wee1 inhibitor, alone or in combination with gemcitabine, in sarcomas.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. 10084-10084
Author(s):  
Jenny Kreahling ◽  
Damon R. Reed ◽  
Parastou Foroutan ◽  
Gary Martinez ◽  
Robert Gillies ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Death ◽  
Soft Tissue ◽  
Soft Tissue Sarcoma ◽  
Therapeutic Efficacy ◽  
Ex Vivo ◽  
Apoptotic Cell ◽  
Apoptotic Cell Death ◽  
Primary Therapy

10084 Background: Sarcomas consist of more than 50 subtypes of mesenchymal tumors. Doxorubicin alone or in combination has been the primary therapy for treatment of sarcomas; however, the response rates are suboptimal in many of the more common adult subtypes of soft tissue sarcoma. Accordingly, new agents are needed for the treatment of this heterogeneous group of diseases. Wee1 is a critical component of the G2/M cell cycle checkpoint control and mediates cell cycle arrest by regulating the phosphorylation of CDC2. Methods: MK1775 treatment of multiple sarcoma preclinical models at clinically relevant concentrations leads to unscheduled entry into mitosis and initiation of apoptotic cell death. In our current study we have investigated the therapeutic efficacy of MK1775 in sarcoma cell lines, patient-derived tumor explants ex vivo and in vivo in a xenograft model of osteosarcoma both alone and in combination with gemcitabine. Results: In patient-derived bone and soft tissue sarcoma samples ex vivo treatments show MK1775 in combination with gemcitabine causes significant apoptotic cell death suggesting that this treatment may represent a novel approach in the treatment of sarcomas. The cytotoxic effect of Wee1 inhibition on sarcoma cells appears to be independent of p53 mutational status. Furthermore, in a patient-derived osteosarcoma xenograft mouse model we show the therapeutic efficacy of MK1775 in vivo by utilizing magnetic resonance imaging (MRI) and diffusion MRI methods. Our data shows MK1775 in combination with gemcitabine dramatically slows tumor growth, increases apoptotic cell death and increases CDC2 activity. Cell viability, a clinically established prognostic indicator of survival, was lowest with the combination and very low in animals treated with MK1775 alone. This was mainly due to increased mineralization of the tumors. Caspase-3 was increased in MK1775 treated animals by immunohistochemistry as well. Conclusions: These results together with the promising safety profile of MK1775 strongly suggest that this drug can be used as a potential therapeutic agent alone or in combination with gemcitabine in the treatment of both adult as well as pediatric sarcoma patients.

scholarly journals Real-time soft tissue motion estimation for lung tumors during radiotherapy delivery

2013 ◽  
Vol 40 (9) ◽  
pp. 091713 ◽  
Author(s):  
Joerg Rottmann ◽  
Paul Keall ◽  
Ross Berbeco
Keyword(s):  
Soft Tissue ◽  
Motion Estimation ◽  
Real Time ◽  
Lung Tumors ◽  
Soft Tissue Motion ◽  
Tissue Motion

Soft tissue motion tracking with application to tablet-based incision planning in laser surgery

2016 ◽  
Vol 11 (12) ◽  
pp. 2325-2337 ◽  
Author(s):  
Andreas Schoob ◽  
Max-Heinrich Laves ◽  
Lüder Alexander Kahrs ◽  
Tobias Ortmaier
Keyword(s):  
Soft Tissue ◽  
Laser Surgery ◽  
Motion Tracking ◽  
Soft Tissue Motion ◽  
Tissue Motion

scholarly journals Stereo vision-based tracking of soft tissue motion with application to online ablation control in laser microsurgery

2017 ◽  
Vol 40 ◽  
pp. 80-95 ◽  
Author(s):  
Andreas Schoob ◽  
Dennis Kundrat ◽  
Lüder A. Kahrs ◽  
Tobias Ortmaier
Keyword(s):  
Soft Tissue ◽  
Stereo Vision ◽  
Laser Microsurgery ◽  
Soft Tissue Motion ◽  
Tissue Motion

scholarly journals SipA Activation of Caspase-3 Is a Decisive Mediator of Host Cell Survival at Early Stages of Salmonella enterica Serovar Typhimurium Infection

2017 ◽  
Vol 85 (9) ◽  
Author(s):  
Anne McIntosh ◽  
Lynsey M. Meikle ◽  
Michael J. Ormsby ◽  
Beth A. McCormick ◽  
John M. Christie ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Actin Polymerization ◽  
Caspase 3 ◽  
Ex Vivo ◽  
Cell Types ◽  
Laser Scanning Microscopy ◽  
Limiting Factor ◽  
Dual Function ◽  
Content Type

ABSTRACT Salmonella invasion protein A (SipA) is a dual-function effector protein that plays roles in both actin polymerization and caspase-3 activation in intestinal epithelial cells. To date its function in other cell types has remained largely unknown despite its expression in multiple cell types and its extracellular secretion during infection. Here we show that in macrophages SipA induces increased caspase-3 activation early in infection. This activation required a threshold level of SipA linked to multiplicity of infection and may be a limiting factor controlling bacterial numbers in infected macrophages. In polymorphonuclear leukocytes, SipA or other Salmonella pathogenicity island 1 effectors had no effect on induction of caspase-3 activation either alone or in the presence of whole bacteria. Tagging of SipA with the small fluorescent phiLOV tag, which can pass through the type three secretion system, allowed visualization and quantification of caspase-3 activation by SipA-phiLOV in macrophages. Additionally, SipA-phiLOV activation of caspase-3 could be tracked in the intestine through multiphoton laser scanning microscopy in an ex vivo intestinal model. This allowed visualization of areas where the intestinal epithelium had been compromised and demonstrated the potential use of this fluorescent tag for in vivo tracking of individual effectors.

scholarly journals Soft Tissue Motion Influences Skeletal Loads During Impacts

2008 ◽  
Vol 36 (2) ◽  
pp. 71-75 ◽  
Author(s):  
John H. Challis ◽  
Matthew T.G. Pain
Keyword(s):  
Soft Tissue ◽  
Soft Tissue Motion ◽  
Tissue Motion

scholarly journals Soft Tissue Motion during Impacts: Their Potential Contributions to Energy Dissipation

2002 ◽  
Vol 18 (3) ◽  
pp. 231-242 ◽  
Author(s):  
Matthew T.G. Pain ◽  
John H. Challis
Keyword(s):  
Soft Tissue ◽  
Muscle Tension ◽  
Force Plate ◽  
Soft Tissue Deformation ◽  
Skin Marker ◽  
Frequency Components ◽  
Distinct Frequency ◽  
Soft Tissue Motion ◽  
Kinetics Of ◽  
Tissue Motion

The aims of this study were to quantify intrasegmental motion using an array of 28 surface-mounted markers to examine frequency and amplitude measurements of the intrasegmental motion to calculate forces and energy transfer; and to show that the underlying muscles are a major contributor to the skin marker motion. One participant performed 27 trials under three conditions in which his forearm was struck against a solid object fixed to a force plate while the locations of the markers were recorded at 240 Hz. For impacts with equal peak forces, the muscle tension significantly affected the amount of intrasegmental motion. Tensing the arm reduced the intrasegmental motion by 50%. The quadrilateral sectors defined by the markers changed in area by 11% with approximately equal motion in the vertical and horizontal direction. The maximum linear marker motion was 1.7 cm. The intrasegmental motion had distinct frequency components around 14 and 20 Hz. Soft tissue deformation could account for 70% of the energy lost from the forearm during these impacts. The study has demonstrated the important role that intrasegment soft tissue motion can have on the kinetics of an impact.

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