Feasibility Check: Can Audio Be a Simple Alternative to Force-Based Feedback for Needle Guidance?

2020 ◽  
pp. 24-33
Author(s):  
Alfredo Illanes ◽  
Axel Boese ◽  
Michael Friebe ◽  
Christian Hansen
Keyword(s):  
Needle Guidance ◽  
Simple Alternative

In vitro validation of a 3-dimensional transrectal ultrasound system for prostate biopsiess

2007 ◽  
Vol 30 (4) ◽  
pp. 77
Author(s):  
Derek Cool ◽  
Shi Sherebrin ◽  
Jonathan Izawa ◽  
Joseph Chin ◽  
Aaron Fenster
Keyword(s):  
Prostate Biopsy ◽  
3D Model ◽  
Transrectal Ultrasound ◽  
Surface Topology ◽  
Sufficient Information ◽  
Needle Guidance ◽  
3 Dimensional ◽  
High Incidence ◽  
3D Information

Introduction: Transrectal ultrasound (TRUS) prostate biopsy (Bx) is currently confined to 2D information to both target and record 3D Bx locations. Accurate placement of Bx needles cannot be verified without 3D information, and recording Bx sites in 2D does not provide sufficient information to accurately guide the high incidence of repeat Bx. We have designed a 3D TRUS prostate Bx system that augments the current 2D TRUS system and provides tools for biopsy-planning, needle guidance, and recording of the biopsy core locations entirely in 3D. Methods: Our Bx system displays a 3D model of the patient’s prostate, which is generated intra-procedure from a collection of 2D TRUS images, representative of the particular prostate shape. Bx targets are selected, needle guidance is facilitated, and 3D Bx sites are recorded within the 3D context of the prostate model. The complete 3D Bx system was validated, in vitro, by performing standard ten-core Bx on anatomical phantoms of two patient’s prostates. The accuracy of the needle-guidance, Bx location recording, and 3D model volume and surface topology were validated against a CT gold standard. Results: The Bx system successfully reconstructed the 3D patient prostate models with a mean volume error of 3.2 ± 7.6%. Using the 3D system, needles were accurately guided to the pre-determined targets with a mean error of 2.26 ± 1.03 mm and the 3D locations of the Bx cores were accurately recorded with a mean distance error of 1.47 ± 0.79 mm. Conclusion: We have successfully developed a 3D TRUS prostate biopsy system and validated the system in vitro. A pilot study has been initiated to apply the system clinically.

scholarly journals Personalized medicine for reconstruction of critical-size bone defects – a translational approach with customizable vascularized bone tissue

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Annika Kengelbach-Weigand ◽  
Carolina Thielen ◽  
Tobias Bäuerle ◽  
Rebekka Götzl ◽  
Thomas Gerber ◽  
...  
Keyword(s):  
Personalized Medicine ◽  
Large Scale ◽  
Critical Size ◽  
Therapeutic Option ◽  
Living Organism ◽  
Bone Defects ◽  
Sheep Model ◽  
Simple Alternative ◽  
Translational Approach ◽  
Near Future

AbstractTissue engineering principles allow the generation of functional tissues for biomedical applications. Reconstruction of large-scale bone defects with tissue-engineered bone has still not entered the clinical routine. In the present study, a bone substitute in combination with mesenchymal stem cells (MSC) and endothelial progenitor cells (EPC) with or without growth factors BMP-2 and VEGF-A was prevascularized by an arteriovenous (AV) loop and transplanted into a critical-size tibia defect in the sheep model. With 3D imaging and immunohistochemistry, we could show that this approach is a feasible and simple alternative to the current clinical therapeutic option. This study serves as proof of concept for using large-scale transplantable, vascularized, and customizable bone, generated in a living organism for the reconstruction of load-bearing bone defects, individually tailored to the patient’s needs. With this approach in personalized medicine for the reconstruction of critical-size bone defects, regeneration of parts of the human body will become possible in the near future.

scholarly journals Asymptotic relative submajorization of multiple-state boxes

2021 ◽  
Vol 111 (4) ◽  
Author(s):  
Gergely Bunth ◽  
Péter Vrana
Keyword(s):  
Hypothesis Testing ◽  
Null Hypothesis ◽  
Alternative Hypothesis ◽  
Standard Form ◽  
Point Of View ◽  
State Discrimination ◽  
Simple Alternative ◽  
Multiple State ◽  
Error Probabilities

AbstractPairs of states, or “boxes” are the basic objects in the resource theory of asymmetric distinguishability (Wang and Wilde in Phys Rev Res 1(3):033170, 2019. 10.1103/PhysRevResearch.1.033170), where free operations are arbitrary quantum channels that are applied to both states. From this point of view, hypothesis testing is seen as a process by which a standard form of distinguishability is distilled. Motivated by the more general problem of quantum state discrimination, we consider boxes of a fixed finite number of states and study an extension of the relative submajorization preorder to such objects. In this relation, a tuple of positive operators is greater than another if there is a completely positive trace nonincreasing map under which the image of the first tuple satisfies certain semidefinite constraints relative to the other one. This preorder characterizes error probabilities in the case of testing a composite null hypothesis against a simple alternative hypothesis, as well as certain error probabilities in state discrimination. We present a sufficient condition for the existence of catalytic transformations between boxes, and a characterization of an associated asymptotic preorder, both expressed in terms of sandwiched Rényi divergences. This characterization of the asymptotic preorder directly shows that the strong converse exponent for a composite null hypothesis is equal to the maximum of the corresponding exponents for the pairwise simple hypothesis testing tasks.

scholarly journals Calendar Spread Exchange Options Pricing with Gaussian Random Fields

Risks ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 77
Author(s):  
Donatien Hainaut
Keyword(s):  
Covariance Structure ◽  
Gaussian Random Fields ◽  
Options Pricing ◽  
Option Prices ◽  
Numerical Illustration ◽  
Simple Alternative ◽  
Asset Values ◽  
Brownian Model ◽  
Exchange Options ◽  
Empirical Covariance

Most of the models leading to an analytical expression for option prices are based on the assumption that underlying asset returns evolve according to a Brownian motion with drift. For some asset classes like commodities, a Brownian model does not fit empirical covariance and autocorrelation structures. This failure to replicate the covariance introduces a bias in the valuation of calendar spread exchange options. As the payoff of these options depends on two asset values at different times, particular care must be taken for the modeling of covariance and autocorrelation. This article proposes a simple alternative model for asset prices with sub-exponential, exponential and hyper-exponential autocovariance structures. In the proposed approach, price processes are seen as conditional Gaussian fields indexed by the time. In general, this process is not a semi-martingale, and therefore, we cannot rely on stochastic differential calculus to evaluate options. However, option prices are still calculable by the technique of the change of numeraire. A numerical illustration confirms the important influence of the covariance structure in the valuation of calendar spread exchange options for Brent against WTI crude oil and for gold against silver.

Comparison of two ultrasound-guided injection techniques targeting the sacroiliac joint region in equine cadavers

2016 ◽  
Vol 29 (05) ◽  
pp. 386-393 ◽  
Author(s):  
Chiara Bergamino ◽  
Ruth Sanders ◽  
Ursula Fogarty ◽  
Antonella Puggioni ◽  
Clodagh Kearney ◽  
...  
Keyword(s):  
Sacroiliac Joint ◽  
Ultra Sound ◽  
Needle Guidance ◽  
Sacroiliac Joints ◽  
Ultrasound Guided ◽  
Joint Region ◽  
Median Distance ◽  
Iodinated Contrast ◽  
Before And After ◽  
Injection Techniques

Summary Objectives: To compare the accuracy and distribution of injectate for cranial (CR) and caudomedial (CM) ultrasound-guided injections of equine sacroiliac joints. Methods: Both sacroiliac joints from 10 lumbo sacropelvic specimens were injected using cranial parasagittal (CR; curved 18 gauge, 25 cm spinal needles) and caudomedial (CM; straight 18 gauge, 15 cm spinal needles) ultrasound-guided approaches. Injectate consisted of 4 ml iodinated contrast and 2 ml methylene blue. Computed tomo-graphical (CT) scans were performed before and after injections. Time for needle guidance and repositioning attempts were recorded. The CT sequences were analysed for accuracy and distribution of contrast. Results: Intra-articular contrast was detected in sacroiliac joints following 15/40 injections. The CR and CM approaches deposited injectate ≤ 2 cm from sacroiliac joint margins following 17/20 and 20/20 injections, respectively. Median distance of closest contrast to the sacroiliac joint was 0.4 cm (interquartile range [IQR]: 1.5 cm) for CR approaches and 0.6 cm (IQR: 0.95 cm) for CM approaches. Cranial injections resulted in injectate contacting lumbosacral intertrans-verse joints 15/20 times. Caudomedial injections were perivascular 16/20 times. Limitations: Safety and efficacy could not be established. Clinical relevance: Cranial and CM ultra-sound-guided injections targeting sacroiliac joints were very accurate for periarticular injection, but accuracy was poor for intra- articular injection. Injectate was frequently found in contact with interosseous sacroiliac ligaments, as well as neurovascular and synovial structures in close vicinity of sacroiliac joints.

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