scholarly journals Intraoperative ultrasound plane wave Doppler imaging allows better definition of gliomal infiltration

2021 ◽  
Vol 1 ◽  
pp. 100486
Author(s):  
I. Zemmoura ◽  
G. Lacoin ◽  
J.-P. Remenieras
Keyword(s):  
Plane Wave ◽  
Intraoperative Ultrasound ◽  
Doppler Imaging ◽  
Definition Of

Development of acoustic target strength near-field equation for underwater vehicles

2018 ◽  
Vol 233 (3) ◽  
pp. 714-721
Author(s):  
Jae-Yong Kim ◽  
Suk-Yoon Hong ◽  
Byung-Gu Cho ◽  
Jee-Hun Song ◽  
Hyun-Wung Kwon
Keyword(s):  
Field Equation ◽  
Plane Wave ◽  
Pressure Field ◽  
Near Field ◽  
Target Strength ◽  
Detection Capability ◽  
Weapon Systems ◽  
Active Sonar ◽  
Acoustic Target ◽  
Definition Of

For modern weapon systems, the most important factor in survivability is detection capability. Acoustic target strength is a major parameter of the active sonar equation. The traditional target strength equation used to predict the re-radiated intensity for the far field is derived with a plane-wave assumption. In this study, a near-field target strength equation was derived without a plane-wave assumption for a polygonal plate. The target strength equation for polygonal plates, which is applicable to the near field, is provided by the Helmholtz–Kirchhoff formula that is used as the primary equation for solving the re-radiated pressure field. A generalized definition of the sonar cross section is suggested that is applicable to the near field. In comparison experiments for a cylinder, the target strength equation for polygonal plates in near field was executed to verify the validity and accuracy of the analysis. In addition, an underwater vehicle model was analyzed with the developed near-field equation to confirm various parameter effects such as distance and frequency.

A beamforming method for plane wave Doppler imaging of high flow velocities

2016 ◽  
Author(s):  
Omar Mansour ◽  
Tamie L. Poepping ◽  
James C. Lacefield
Keyword(s):  
Plane Wave ◽  
High Flow ◽  
Doppler Imaging ◽  
Flow Velocities

THE UNIVERSAL EQUATIONS OF MOTION FOR NONLINEAR FIELDS IN DIFFERENT BASES DESCRIBING STRONGLY INTERACTING MANY-BODY SYSTEMS WITH TWO-BODY INTERACTIONS

1995 ◽  
Vol 09 (13n14) ◽  
pp. 1611-1637 ◽  
Author(s):  
J.M. DIXON ◽  
J.A. TUSZYŃSKI
Keyword(s):  
Plane Wave ◽  
Coherent Structures ◽  
Equations Of Motion ◽  
Quantum Field ◽  
Many Body ◽  
Field Equations ◽  
Strongly Interacting ◽  
Highly Nonlinear ◽  
Many Body Systems ◽  
Definition Of

A brief account of the Method of Coherent Structures (MCS) is presented using a plane-wave basis to define a quantum field. It is also demonstrated that the form of the quantum field equations, obtained by MCS, although highly nonlinear for many-body systems with two-body interactions, is independent of the basis of states used for the definition of the field.

scholarly journals Evaluation of Intraoperative Surgical Adjuncts and Resection of Glioblastoma (ELISAR GB): A UK and Ireland, multicentre, prospective observational cohort study

2021 ◽  
Vol 23 (Supplement_4) ◽  
pp. iv6-iv7
Author(s):  
Georgios Solomou ◽  
Ali Gharooni ◽  
Rory J Piper ◽  
Angelos G Kolias ◽  
Daniel M Fountain ◽  
...  
Keyword(s):  
Cohort Study ◽  
Aminolevulinic Acid ◽  
Intraoperative Ultrasound ◽  
Extent Of Resection ◽  
Conclusive Evidence ◽  
Complete Resection ◽  
Awake Surgery ◽  
National Study ◽  
Definition Of ◽  
The Uk

Abstract Aims Extent of resection is associated with better survival in patients with glioblastoma. Numerous surgical adjuncts can be used to achieve maximal safe resection - including fluorescence-guidance with 5-aminolevulinic acid (5-ALA), neuronavigation, intraoperative ultrasound (IoUS), intra-operative MRI (iMRI), tractography, electrophysiological monitoring and awake surgery. We evaluated the availability, use and operative aim and success associated with these adjuncts. Method This is a prospective cohort study of 27 of 31 neurosurgical centres in the UK and Ireland from 6 January to 19 March 2020. Consecutive cases were identified through neuro-oncology multidisciplinary meetings. Eligible cases included adults with a supratentorial histopathologically confirmed glioblastoma with pre/post-operative reported T1-weighted MRI with contrast deemed suitable for resection. Outcomes included the availability and usage of surgical adjuncts, and the percentage of operations that achieved their aim of complete resection, defined as complete resection of enhancing tumour (CRET) on post-operative T1-MRI. We present the initial descriptive statistics from this national study. Results 232 patients with glioblastoma were included. In 142 patients (61.2%) the surgical aim was CRET. 5-ALA and neuronavigation were available in all centres (Figure 1). The most commonly used neurosurgical adjunct was neuronavigation (88.2%) (Figure 2). The proportion of patients receiving 5-ALA in CRET and debulking-only groups was 65.0% and 48.9%, respectively. 35 different combinations of adjuncts were found in total, with 13 unique combinations only used in one instance (Figures 1 & 2). CRET was achieved in 69/142 (45.8%) patients in which was the aim. 9/90 (10%) patients in the debulking-only group achieved CRET, of which 7/9 (77.8%) had received 5-ALA. Of the three most frequently used combination of adjuncts for patients deemed feasible for CRET, the most successful in terms of achieving CRET was the combined use of neuronavigation, 5-ALA and IoUS, with post-operative CRET at 47.4% (Figure 3). Conclusion ELISAR-GB has collated prospective data to demonstrate the current use of intraoperative adjuncts in the UK and Ireland. There is marked heterogeneity with regards to combinations of adjuncts used. A CRET of 47% is lower than would be expected compared to previously published literature, possibly due to a more stringent definition of complete resection in this study. Based on these early descriptive results, there is no clear combination of adjuncts that shows superiority and use of 5-ALA does not always result in CRET when it is the surgical aim. Of interest, 5-ALA is being used for operations that do not aim for complete resection, a change in indication. The FUTURE GB trial will provide more conclusive evidence on the efficacy of surgical adjuncts to maximise extent of resection.

In vivo out-of-plane Doppler imaging based on ultrafast plane wave imaging

2013 ◽  
Author(s):  
Bruno-Felix Osmanski ◽  
Gabriel Montaldo ◽  
Mathias Fink ◽  
Mickael Tanter
Keyword(s):  
Plane Wave ◽  
Doppler Imaging ◽  
Out Of Plane ◽  
Wave Imaging

Combined perfusion and doppler imaging using plane-wave nonlinear detection and microbubble contrast agents

2014 ◽  
Vol 61 (12) ◽  
pp. 1988-2000 ◽  
Author(s):  
Charles Tremblay-Darveau ◽  
Ross Williams ◽  
Laurent Milot ◽  
Matthew Bruce ◽  
Peter N. Burns
Keyword(s):  
Plane Wave ◽  
Contrast Agents ◽  
Doppler Imaging ◽  
Microbubble Contrast Agents ◽  
Nonlinear Detection

scholarly journals Discrete or diffuse intramedullary tumor? Contrast-enhanced intraoperative ultrasound in a case of intramedullary cervicothoracic hemangioblastomas mimicking a diffuse infiltrative glioma: technical note and case report

2015 ◽  
Vol 39 (2) ◽  
pp. E17 ◽  
Author(s):  
Ignazio G. Vetrano ◽  
Francesco Prada ◽  
Ilaria F. Nataloni ◽  
Massimiliano Del Bene ◽  
Francesco Dimeco ◽  
...  
Keyword(s):  
Intraoperative Ultrasound ◽  
Technical Note ◽  
Complete Resection ◽  
Intramedullary Tumor ◽  
Neurosurgical Procedures ◽  
Diffuse Astrocytoma ◽  
Intramedullary Tumors ◽  
Contrast Enhanced ◽  
Definition Of ◽  
Intradural Space

Hemangioblastomas are benign, highly vascularized intramedullary lesions that may also extend into the intradural space. Surgery represents the standard therapy, with the goal of obtaining complete resection even at the risk of neurological morbidity. MRI is the gold standard for diagnosis and assessment of intramedullary tumors. Nevertheless, sometimes MRI may not accurately differentiate between different types of intramedullary tumors, in particular if they are associated with syringes or intra- and peritumoral cysts. This could subsequently affect surgical strategies. Intraoperative ultrasound (ioUS) has become in the last few years a very useful tool for use during neurosurgical procedures. Various ioUS modalities such as B-mode and Doppler have been applied during neurosurgical procedures. On the other hand, the use of contrast-enhanced ultrasound (CEUS) is not yet well defined and standardized in this field. We report a case of a young patient harboring a cervicothoracic intramedullary tumor, for which the preoperative neuroradiologi-cal diagnosis was in favor of a diffuse astrocytoma with nodular components whereas ioUS demonstrated 3 distinct intramedullary nodules. CEUS showed highly vascularized lesions, compatible with hemangioblastomas. These findings, particularly those obtained with CEUS, allowed better definition of the lesions for diagnosis, enhanced understanding of the physiopathological aspects, and permitted the localization of all 3 nodules, thus limiting spinal cord manipulation and allowing complete resection of the lesions, with an uneventful postoperative neurological course. To the best of our knowledge, this is the first report of the use of intraoperative CEUS in a case of intramedullary hemangioblastoma.

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