scholarly journals Monitoring of Biological Changes in Electromechanical Reshaping of Cartilage Using Imaging Modalities

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Seok Jin Hong ◽  
Minseok Lee ◽  
Connie J. Oh ◽  
Sehwan Kim
Keyword(s):  
Minimally Invasive ◽  
Structural Changes ◽  
Thermal Damage ◽  
Imaging Modality ◽  
Local Stress ◽  
Imaging Modalities ◽  
Structural Deformation ◽  
Electrochemical Mechanism ◽  
Tissue Matrix ◽  
Cartilage Reshaping

Electromechanical reshaping (EMR) is a promising surgical technique used to reshape cartilage by direct current and mechanical deformation. It causes local stress relaxation and permanent alterations in the shape of cartilage. The major advantages of EMR are its minimally invasive nature and nonthermal electrochemical mechanism of action. The purpose of this study is to validate that EMR does not cause thermal damage and to observe structural changes in post-EMR cartilage using several imaging modalities. Three imaging modality metrics were used to validate the performance of EMR by identifying structural deformation during cartilage reshaping: infrared thermography was used to sense the temperature of the flat cartilages (16.7°C at 6 V), optical coherence tomography (OCT) was used to examine the change in the cartilage by gauging deformation in the tissue matrix during EMR, and scanning electron microscopy (SEM) was used to show that EMR-treated cartilage is irregularly arranged and the thickness of collagen fibers varies, which affects the change in shape of the cartilage. In conclusion, the three imaging modalities reveal the nonthermal and electromechanical mechanisms of EMR and demonstrate that use of an EMR device is feasible for reshaping cartilage in a minimally invasive manner.

scholarly journals An investigation of the use of transmission ultrasound to guide minimally invasive thermal therapy

2021 ◽  
Author(s):  
Elham Soleimankhani
Keyword(s):  
Minimally Invasive ◽  
Real Time ◽  
Structural Changes ◽  
Imaging Modality ◽  
Thermal Therapy ◽  
Tissue Temperature ◽  
Imaging Method ◽  
Target Tissue ◽  
Acoustic Attenuation ◽  
Real Time Imaging

Minimally Invasive Thermal Therapy (MITT) is an effective way for the treatment of localized cancer and could replace surgery, chemotherapy or radiation. During MITT, high temperatures in the range of 55-95 °C are produced locally in the target tissue or tumour, resulting in localized protein coagulation. A real-time imaging method is required to guide the procedure of thermal therapy. Ideally, this imaging modality should be noninvasive, inexpensive and easily used and interpreted. It is known that acoustic attenuation is sensitive to both the tissue temperature and the structural changes due to protein coagulation (the endpoint of any thermal therapy treatment) during thermal therapy. Transmission ultrasound imaging is a real-time imaging modality which measures the attenuation property of ultrasound. The goal of this work is to demonstrate the potential of ultrasound attenuation imaging during MITT to quantitatively monitor lesion formation dynamics. An important finding of the present study is that the temporal changes in acoustic attenuation during MITT follow a reproducible pattern in albumen phantoms and bovine liver tissue within the range of thermal therapy temperatures. After heating, the measured attenuation remains higher than the initial amount, suggesting that this irreversible increase is a result of the structural change due to protein coagulation.

scholarly journals The macaque brain ONPRC18 template with combined gray and white matter labelmap for multimodal neuroimaging studies of nonhuman primates

2020 ◽  
Author(s):  
Alison R Weiss ◽  
Zheng Liu ◽  
Xiaojie Wang ◽  
William A Liguore ◽  
Christopher D. Kroenke ◽  
...  
Keyword(s):  
White Matter ◽  
Structural Changes ◽  
Diffusion Tensor ◽  
Rhesus Macaques ◽  
Imaging Modality ◽  
Brain Atlas ◽  
Imaging Modalities ◽  
Imaging Data ◽  
Multiple Imaging ◽  
T1 And T2

ABSTRACTMacaques are the most common nonhuman primate (NHP) species used in neuroscience research. With the advancement of many neuroimaging techniques, new studies are beginning to apply multiple types of in vivo magnetic resonance imaging (MRI), such as structural imaging (sMRI) with T1 and T2 weighted contrasts alongside diffusion weighed (DW) imaging. In studies involving rhesus macaques, this approach can be used to better understand micro-structural changes that occur during development, in various disease states or with normative aging. However, many of the available rhesus brain atlases have been designed for only one imaging modality, making it difficult to consistently define the same brain regions across multiple imaging modalities in the same subject. To address this, we created a brain atlas from 18 adult rhesus macaques that includes co-registered templates constructed from images frequently used to characterize macroscopic brain structure (T2/SPACE and T1/MP-RAGE), and a diffusion tensor imaging (DTI) template. The DTI template was up-sampled from 1 mm isotropic resolution to resolution match to the T1 and T2-weighted images (0.5 mm isotropic), and the parameter map was derived for fractional anisotropy (FA). The labelmap volumes delineate 57 gray matter regions of interest (ROIs; 36 cortical regions and 21 subcortical structures), as well as 74 white matter tracts. Importantly, the labelmap overlays both the structural and diffusion templates, enabling the same regions to be consistently identified across imaging modalities. A specialized condensed version of the labelmap ROIs are also included to further extend the usefulness of this tool for imaging data with lower spatial resolution, such as functional MRI (fMRI) or positron emission tomography (PET). Graphical Abstract

scholarly journals An investigation of the use of transmission ultrasound to guide minimally invasive thermal therapy

2021 ◽  
Author(s):  
Elham Soleimankhani
Keyword(s):  
Minimally Invasive ◽  
Real Time ◽  
Structural Changes ◽  
Imaging Modality ◽  
Thermal Therapy ◽  
Tissue Temperature ◽  
Imaging Method ◽  
Target Tissue ◽  
Acoustic Attenuation ◽  
Real Time Imaging

Minimally Invasive Thermal Therapy (MITT) is an effective way for the treatment of localized cancer and could replace surgery, chemotherapy or radiation. During MITT, high temperatures in the range of 55-95 °C are produced locally in the target tissue or tumour, resulting in localized protein coagulation. A real-time imaging method is required to guide the procedure of thermal therapy. Ideally, this imaging modality should be noninvasive, inexpensive and easily used and interpreted. It is known that acoustic attenuation is sensitive to both the tissue temperature and the structural changes due to protein coagulation (the endpoint of any thermal therapy treatment) during thermal therapy. Transmission ultrasound imaging is a real-time imaging modality which measures the attenuation property of ultrasound. The goal of this work is to demonstrate the potential of ultrasound attenuation imaging during MITT to quantitatively monitor lesion formation dynamics. An important finding of the present study is that the temporal changes in acoustic attenuation during MITT follow a reproducible pattern in albumen phantoms and bovine liver tissue within the range of thermal therapy temperatures. After heating, the measured attenuation remains higher than the initial amount, suggesting that this irreversible increase is a result of the structural change due to protein coagulation.

scholarly journals Impact of the COVID-19 pandemic on the selection of chest imaging modalities and reporting systems: a survey of Italian radiologists

2021 ◽  
Author(s):  
Andrea Borghesi ◽  
Nicola Sverzellati ◽  
Roberta Polverosi ◽  
Maurizio Balbi ◽  
Elisa Baratella ◽  
...  
Keyword(s):  
Continuing Education ◽  
Reporting System ◽  
Imaging Modality ◽  
Diagnostic Technique ◽  
Imaging Modalities ◽  
Chest Imaging ◽  
Reporting Systems ◽  
Imaging Approach ◽  
Narrative Report ◽  
Selection Of

Abstract Purpose Chest imaging modalities play a key role for the management of patient with coronavirus disease (COVID-19). Unfortunately, there is no consensus on the optimal chest imaging approach in the evaluation of patients with COVID-19 pneumonia, and radiology departments tend to use different approaches. Thus, the main objective of this survey was to assess how chest imaging modalities have been used during the different phases of the first COVID-19 wave in Italy, and which diagnostic technique and reporting system would have been preferred based on the experience gained during the pandemic. Material and Methods The questionnaire of the survey consisted of 26 questions. The link to participate in the survey was sent to all members of the Italian Society of Medical and Interventional Radiology (SIRM). Results The survey gathered responses from 716 SIRM members. The most notable result was that the most used and preferred chest imaging modality to assess/exclude/monitor COVID-19 pneumonia during the different phases of the first COVID-19 wave was computed tomography (51.8% to 77.1% of participants). Additionally, while the narrative report was the most used reporting system (55.6% of respondents), one-third of participants would have preferred to utilize structured reporting systems. Conclusion This survey shows that the participants’ responses did not properly align with the imaging guidelines for managing COVID-19 that have been made by several scientific, including SIRM. Therefore, there is a need for continuing education to keep radiologists up to date and aware of the advantages and limitations of the chest imaging modalities and reporting systems.

scholarly journals Accuracy of Commonly-Used Imaging Modalities in Assessing Left Atrial Appendage for Interventional Closure: Review Article

2018 ◽  
Vol 7 (11) ◽  
pp. 441 ◽  
Author(s):  
Ramez Morcos ◽  
Haider Al Taii ◽  
Priya Bansal ◽  
Joel Casale ◽  
Rupesh Manam ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Transesophageal Echocardiography ◽  
Left Atrial ◽  
Left Atrial Appendage ◽  
Imaging Modality ◽  
Three Dimensional ◽  
Atrial Appendage ◽  
Imaging Modalities ◽  
Three Dimensional Printing ◽  
Dimensional Printing

Periprocedural imaging assessment for percutaneous Left Atrial Appendage (LAA) transcatheter occlusion can be obtained by utilizing different imaging modalities including fluoroscopy, magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound imaging. Given the complex and variable morphology of the left atrial appendage, it is crucial to obtain the most accurate LAA dimensions to prevent intra-procedural device changes, recapture maneuvers, and prolonged procedure time. We therefore sought to examine the accuracy of the most commonly utilized imaging modalities in LAA occlusion. Institutional Review Board (IRB) approval was waived as we only reviewed published data. By utilizing PUBMED which is an integrated online website to list the published literature based on its relevance, we retrieved thirty-two articles on the accuracy of most commonly used imaging modalities for pre-procedural assessment of the left atrial appendage morphology, namely, two-dimensional transesophageal echocardiography, three-dimensional transesophageal echocardiography, computed tomography, and three-dimensional printing. There is strong evidence that real-time three-dimensional transesophageal echocardiography is more accurate than two-dimensional transesophageal echocardiography. Three-dimensional computed tomography has recently emerged as an imaging modality and it showed exceptional accuracy when merged with three-dimensional printing technology. However, real time three-dimensional transesophageal echocardiography may be considered the preferred imaging modality as it can provide accurate measurements without requiring radiation exposure or contrast administration. We will present the most common imaging modality used for LAA assessment and will provide an algorithmic approach including preprocedural, periprocedural, intraprocedural, and postprocedural.

scholarly journals Imaging of Fibrosis in Chronic Pancreatitis

2022 ◽  
Vol 12 ◽  
Author(s):  
Yasunobu Yamashita ◽  
Reiko Ashida ◽  
Masayuki Kitano
Keyword(s):  
Chronic Pancreatitis ◽  
Magnetic Resonance ◽  
Imaging Modality ◽  
Magnetic Resonance Cholangiopancreatography ◽  
Imaging Modalities ◽  
Diagnostic Tools ◽  
Diagnostic Modality ◽  
Magnetic Resonance Imaging Mri ◽  
Initial Imaging ◽  
Eus Elastography

Chronic pancreatitis (CP) describes long-standing inflammation of the pancreas, which leads to irreversible and progressive inflammation of the pancreas with fibrosis. CP also leads to abdominal pain, malnutrition, and permanent impairment of exocrine/endocrine functions. However, it is difficult to assess CP pathologically, and imaging modalities therefore play an important role in the diagnosis and assessment of CP. There are four modalities typically used to assess CP. Pancreatic duct features are assessed with magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP). However, ERCP is a rather invasive diagnostic modality for CP, and can result in adverse events such as post-ERCP pancreatitis. Computed tomography (CT) is often the most appropriate initial imaging modality for patients with suspected CP, and has high diagnostic specificity. However, CT findings typically only appear in advanced stages of CP, and it is difficult to detect early CP. Endoscopic ultrasonography (EUS) provides superior spatial resolution compared with other imaging modalities such as CT and magnetic resonance imaging (MRI), and is considered the most reliable and efficient diagnostic modality for pancreatic diseases. The EUS-based Rosemont classification plays an important role in diagnosing CP in clinical practice. Evaluation of tissue stiffness can be another option to assess the diagnosis and progression of CP, and MRI and EUS can be used to assess CP not only with imaging, but also with elasticity measurement. MR and EUS elastography are expected to provide new alternative diagnostic tools for assessment of fibrosis in CP, which is difficult to evaluate pathologically.

Experimental Investigation on Grinding Temperature of Titanium Alloy

2014 ◽  
Vol 1027 ◽  
pp. 127-130 ◽  
Author(s):  
Bing Jun Hao ◽  
Zhi Gang Dong ◽  
Ren Ke Kang ◽  
Huan Wang ◽  
Ke Cao
Keyword(s):  
Titanium Alloy ◽  
Structural Changes ◽  
Thermal Damage ◽  
Elevated Temperatures ◽  
Chemical Properties ◽  
Grinding Temperature ◽  
Physical And Chemical Properties ◽  
Machine Material ◽  
Physical And Chemical ◽  
And Chemical Properties

Titanium alloy has been widely used in aeronautics and astronautics industry owing to its unique combinations of properties. The unique physical and chemical properties of titanium alloy make it a typical difficult-to-machine material. The elevated temperatures at the machining zones may cause thermal damage, residual stress and micro-structural changes in the surface layer of titanium alloy during grinding. In this study, grinding experiments were performed on the titanium alloy, and the grinding temperature was experimentally tested with the grindable thermocouples. The effects of the grinding parameters on the grinding temperature were analyzed. The grinding temperature rises with the increase of grinding speed and grinding depth.

scholarly journals Structural deformation and host–guest properties of doubly-reduced cycloparaphenylenes, [n]CPPs2− (n = 6, 8, 10, and 12)

2020 ◽  
Vol 11 (35) ◽  
pp. 9395-9401 ◽  
Author(s):  
Zheng Zhou ◽  
Zheng Wei ◽  
Tobias A. Schaub ◽  
Ramesh Jasti ◽  
Marina A. Petrukhina
Keyword(s):  
Structural Changes ◽  
Structural Deformation ◽  
Size Dependent

The series of doubly-reduced cycloparaphenylenes (CPPs) with increasing dimensions and flexibility shows the size-dependent structural changes and enhanced host abilities.

scholarly journals Suprapubic penetrating abdominal trauma - defining peritoneal breach and choices in operative intervention

2019 ◽  
Vol 2019 (11) ◽  
Author(s):  
Michael J Papanikolas ◽  
Anik Sarkar ◽  
Shivanthi Kandiah ◽  
Navin Niles
Keyword(s):  
Minimally Invasive ◽  
Abdominal Trauma ◽  
Operative Intervention ◽  
Organ Injury ◽  
Imaging Modalities ◽  
Abdominal Organ ◽  
Penetrating Abdominal Trauma ◽  
Stab Injury ◽  
Laparoscopic Techniques ◽  
Invasive Management

Abstract Penetrating abdominal trauma is an uncommon cause of presentation to emergency departments in Australia and is frequently associated with the clinical need for emergent operative intervention. Advances in imaging modalities, improved laparoscopic techniques and structured approaches to resuscitation in trauma have now allowed potential minimally invasive management of such injuries, avoiding laparotomy and therefore defining peritoneal breach; the major determinant of intra-abdominal organ injury in this setting is critical. We present the case of a self-inflicted stab injury to the suprapubic region in an otherwise healthy man and describe the combination of imaging and operative modalities used to define peritoneal breach in this case which successfully reduced the patient’s morbidity by avoiding non-therapeutic laparotomy.

scholarly journals Volar Plating: Imaging Modalities for the Detection of Screw Penetration

2019 ◽  
Vol 08 (06) ◽  
pp. 520-530
Author(s):  
Minke Bergsma ◽  
Katharina Denk ◽  
Job N. Doornberg ◽  
Michel P. J. van den Bekerom ◽  
Gino M. M. J. Kerkhoffs ◽  
...  
Keyword(s):  
Distal Radius ◽  
Imaging Modality ◽  
Distal Radius Fractures ◽  
Imaging Modalities ◽  
In Vivo Studies ◽  
Volar Plating ◽  
Radius Fractures ◽  
Level Of Evidence ◽  
Additional Imaging ◽  
Screw Penetration

Abstract Background Volar plating for distal radius fractures exposes the risk of extensor tendon rupture, mechanical problems, and osteoarthritis due to protruding screws. Purposes The purpose of this review was to identify the best intraoperative diagnostic imaging modality to identify dorsal and intra-articular protruding screws in volar plating for distal radius fractures. Methods The Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were followed for this review. In vitro and in vivo studies that analyzed the reliability, efficacy, and/or accuracy of intraoperatively available imaging modalities for the detection of dorsal or intra-articular screw protrusion after volar plating for distal radius fractures were included. Results Described additional imaging modalities are additional fluoroscopic views (pronated views, dorsal tangential view [DTV], radial groove view [RGV], and carpal shoot through [CST] view), three-dimensional (3D) and rotational fluoroscopies, and ultrasound (US). For detection of dorsal screw penetration, additional fluoroscopic views show better results than conventional views. Based on small (pilot) studies, US seems to be promising. For intra-articular screw placement, 3D or 360 degrees fluoroscopy shows better result than conventional views. Conclusion Based on this systematic review, the authors recommend the use of at least one of the following additional imaging modalities to prevent dorsal protruding screws: CST view, DTV, or RGV. Tilt views are recommended for intra-articular assessment. Of all additional fluoroscopic views, the DTV is most studied and proves to be practical and time efficient, with higher efficacy, accuracy, and reliability compared with conventional views. Level of Evidence The level of evidence is Level III.

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