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https://www.readbyqxmd.com/read/29687916/mri-based-wireless-determination-of-the-transfer-function-of-a-linear-implant-introduction-of-the-transfer-matrix
#1
Janot P Tokaya, Alexander J E Raaijmakers, Peter R Luijten, Cornelis A T van den Berg
PURPOSE: We introduce the transfer matrix (TM) that makes MR-based wireless determination of transfer functions (TFs) possible. TFs are implant specific measures for RF-safety assessment of linear implants. The TF relates an incident tangential electric field on an implant to a scattered electric field at its tip that generally governs local heating. The TM extends this concept and relates an incident tangential electric field to a current distribution in the implant therewith characterizing the RF response along the entire implant...
April 24, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29682611/unilateral-renal-tumor-cryoablation-and-contralateral-radical-nephrectomy-of-bilateral-renal-tumors-by-transumbilical-3d-multichannel-laparoendoscopic-single-site-surgery
#2
Guopeng Yu, Ke Zhang, Wenzhi Li, Long Li, Yanliang Zhao, Yiwei Wang, Mingxi Xu, Jun Da, Guoqin Dong, Zhong Wang, Bin Xu
Background: Unilateral renal tumor cryoablation and contralateral radical nephrectomy of bilateral renal tumors were performed by transumbilical three-dimensional (3D) multichannel laparoendoscopic single-site (LESS) surgery, in an attempt to verify the feasibility and safety of the procedure, sum up the operational experience, and evaluate the surgical outcome. Case Presentation: This was a 47-year-old female patient with a body mass index of 27.34 kg/m2 without backache, low back pain, hematuria, urinary urgency, frequent urination, dysuria, and other symptoms...
2018: Journal of Endourology Case Reports
https://www.readbyqxmd.com/read/29680960/a-comparison-of-safety-and-efficacy-of-dexmedetomidine-and-propofol-in-children-with-autism-and-autism-spectrum-disorders-undergoing-magnetic-resonance-imaging
#3
Kamal Abulebda, Ryan Louer, Riad Lutfi, Sheikh Sohail Ahmed
Children with autism and autism spectrum disorders have a high incidence of neurologic comorbidities. Consequently, evaluation with magnetic resonance imaging (MRI) is deemed necessary. Sedating these patients poses several challenges. This retrospective study compared the efficacy and safety of dexmedetomidine to propofol in sedating autistic patients undergoing MRI. There were 56 patients in the dexmedetomidine group and 49 in the propofol group. All of the patients successfully completed the procedure. Recovery and discharge times were significantly lower in the propofol group, while the dexmedetomidine group maintained more stable hemodynamics...
April 21, 2018: Journal of Autism and Developmental Disorders
https://www.readbyqxmd.com/read/29680674/multifunctional-hybrid-nanoconstruct-of-zerovalent-iron-and-carbon-dots-for-magnetic-resonance-angiography-and-optical-imaging-an-in-vivo-study
#4
N Nimi, Ariya Saraswathy, Shaiju S Nazeer, Nimmi Francis, Sachin J Shenoy, Ramapurath S Jayasree
In magnetic resonance imaging (MRI), gadolinium (Gd) complexes are very often used as contrast agents to enhance the signal from soft tissue deformities and vascular anomalies, to improve the accuracy of diagnosis. The safety concern of using Gd complexes in renally compromised patients pose limitations on its application. To overcome this scenario, we introduce a nontoxic zerovalent iron based nanoparticle as a novel contrast agent for MR angiography and a hybrid version of the same to serve as a dual function contrast agent for targeted liver imaging...
April 10, 2018: Biomaterials
https://www.readbyqxmd.com/read/29679498/7t-ultra-high-field-body-mr-imaging-with-an-8-channel-transmit-32-channel-receive-radiofrequency-coil-array
#5
Stefan H G Rietsch, Stephan Orzada, Stefan Maderwald, Sascha Brunheim, Bart W J Philips, Tom W J Scheenen, Mark E Ladd, Harald H Quick
PURPOSE: In this work a combined body coil array with 8 transmit/receive (Tx/Rx) meander elements and with 24 receive-only (Rx) loops (8Tx/32Rx) was developed and evaluated in comparison to an 8-channel transmit/receive body array (8Tx/Rx) based on meander elements serving as the reference standard. METHODS: Systematic evaluation of the RF array was performed on a body-sized phantom. Body imaging at 7T was performed in 6 volunteers in the body regions pelvis, abdomen, and heart...
April 21, 2018: Medical Physics
https://www.readbyqxmd.com/read/29673691/laparoscopic-inguinal-ligament-suspension-with-uterine-preservation-for-pelvic-organ-prolapse-a-retrospective-cohort-study
#6
Chunbo Li, Huimin Shu, Zhiyuan Dai
OBJECTIVE: To introduce an alternative surgical technique of laparoscopic inguinal ligament suspension (LILS) with uterine preservation and evaluate its efficacy and safety for patients with severe pelvic organ prolapse (POP). METHODS: Between June 2014 and December 2015, 35 patients with symptomatic stage III or IV were treated by LILS with uterine preservation. The perioperative parameters including surgical time, blood loss, hospital stay and complications were recorded...
April 16, 2018: International Journal of Surgery
https://www.readbyqxmd.com/read/29671007/additional-value-of-contrast-enhanced-ultrasonography-for-fusion-guided-percutaneous-biopsies-of-focal-liver-lesions-prospective-feasibility-study
#7
Hyo-Jin Kang, Jung Hoon Kim, Sang Min Lee, Hyun Kyung Yang, Su Joa Ahn, Joon Koo Han
PURPOSE: To determine the value of CEUS for real-time, fusion-guided, percutaneous biopsies of focal liver lesions. MATERIALS AND METHODS: Institutional review board approval and written informed consents were obtained for this study. Forty patients with focal liver lesions identified on CT/MRI were prospectively enrolled. For biopsy planning, real-time fusion of CT/MRI with USG (USG-Fusion) was performed, and subsequently real-time CEUS was fused with CT/MRI (CEUS-Fusion)...
April 18, 2018: Abdominal Radiology
https://www.readbyqxmd.com/read/29652301/-the-results-of-an-open-comparative-retrospective-trial-of-the-course-of-multiple-sclerosis-during-treatment-with-infibeta-and-other-interferon-beta-bioanalogues-and-glatiramer-acetate
#8
F A Khabirov, T I Khaybullin, E V Granatov, S R Shakirzianova, N N Babicheva, O S Kochergina, E F Rakhmatullina, G M Akhmedova, L A Averyanova, M A Yakupov, Zh F Sabirov
AIM: To evaluate the efficacy and safety of the interferon beta-1b bioanalogue 'infibeta' in the treatment of multiple sclerosis (MS) in comparison with other interferon beta bioanalogues and the generic drug glatiramer acetate. MATERIAL AND METHODS: The data of 500 patients with MS treated with different disease-modifying drugs were analyzed. Patients of group 1 (n=95) received infibeta; group 2 (n=108) interferon beta-1b; group 3 (n=83) genfaxon-44; group 4 (n=109) sinnovex; group 5 (n=105) aksoglatiran FS...
2018: Zhurnal Nevrologii i Psikhiatrii Imeni S.S. Korsakova
https://www.readbyqxmd.com/read/29652234/computer-assisted-planning-for-the-insertion-of-stereoelectroencephalography-electrodes-for-the-investigation-of-drug-resistant-focal-epilepsy-an-external-validation-study
#9
Vejay N Vakharia, Rachel Sparks, Roman Rodionov, Sjoerd B Vos, Christian Dorfer, Jonathan Miller, Daniel Nilsson, Martin Tisdall, Stefan Wolfsberger, Andrew W McEvoy, Anna Miserocchi, Gavin P Winston, Aidan G O'Keeffe, Sebastien Ourselin, John S Duncan
OBJECTIVE One-third of cases of focal epilepsy are drug refractory, and surgery might provide a cure. Seizure-free outcome after surgery depends on the correct identification and resection of the epileptogenic zone. In patients with no visible abnormality on MRI, or in cases in which presurgical evaluation yields discordant data, invasive stereoelectroencephalography (SEEG) recordings might be necessary. SEEG is a procedure in which multiple electrodes are placed stereotactically in key targets within the brain to record interictal and ictal electrophysiological activity...
April 13, 2018: Journal of Neurosurgery
https://www.readbyqxmd.com/read/29651017/effects-of-different-doses-of-granulocyte-colony-stimulating-factor-mobilization-therapy-on-ischemic-cardiomyopathy
#10
Rongchong Huang, Haichen Lv, Kang Yao, Lei Ge, Zhishuai Ye, Huaiyu Ding, Yiqi Zhang, Hao Lu, Zheyong Huang, Shuning Zhang, Yunzeng Zou, Junbo Ge
G-CSF mobilization might be beneficial to ICM, but the relationship between effect/safety and the dosage of G-CSF remains unclear. In this study, 24 pigs were used to build ICM models and were randomized into four groups. Four weeks later, different dosages of G-CSF were given daily by subcutaneous injection for 5 days. Another 4 weeks later, all the animals were sacrificed. Electrocardiography, coronary arteriography, left ventriculography, transthoracic echocardiography, cardiac MRI, and SPECT, histopathologic analysis, and immunohistochemistry techniques were used to evaluate left ventricular function and myocardial infarct size...
April 12, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29645347/does-the-introduction-of-prostate-multiparametric-mri-into-active-surveillance-of-localised-prostate-cancer-improve-patient-re-classification
#11
R J Bryant, B Yang, Y Philippou, K Lam, M Obiakor, J Ayers, V Chiocchia, F Gleeson, R MacPherson, C Verrill, P Sooriakumaran, F C Hamdy, S F Brewster
OBJECTIVES: To determine whether replacement of protocol-driven repeat prostate biopsy (PB) with multiparametric magnetic resonance imaging (mpMRI) +/- targeted repeat prostate biopsy (TB) in evaluating men on active surveillance (AS) for low-volume low- to intermediate-risk prostate cancer (PCa) altered the likelihood or time to treatment, or reduced the number of repeat biopsies required to trigger treatment. PATIENTS AND METHODS: 445 patients underwent AS from 2010-2016 at our institution with median follow-up of 2...
April 12, 2018: BJU International
https://www.readbyqxmd.com/read/29643169/safety-and-feasibility-evaluation-of-tourniquets-for-total-knee-replacement-safe-tkr-study-protocol
#12
Peter Dh Wall, Imran Ahmed, Andrew Metcalfe, Andrew J Price, Kate Seers, Charles E Hutchinson, Helen Parsons, Jane Warwick, Bushra Rahman, Jaclyn Brown, Martin Underwood
INTRODUCTION: This study is designed to determine whether a full randomised controlled trial (RCT) examining the clinical effectiveness and safety of total knee replacement surgery with or without a tourniquet is warranted and feasible. METHOD AND ANALYSIS: Single centre, patient-blinded and assessor-blinded RCT. A computer-generated randomisation service will allocate 50 participants into one of two trial treatments, surgery with or without a tourniquet. The primary objective is to estimate recruitment, crossovers and follow-up of patients...
April 10, 2018: BMJ Open
https://www.readbyqxmd.com/read/29642961/preoperative-magnetic-resonance-imaging-diagnostic-features-of-uterine-leiomyosarcomas-a-systematic-review
#13
Helen Kaganov, Alex Ades, David Stuart Fraser
OBJECTIVES: There are no current established pathognomonic diagnostic features for uterine leiomyosarcomas in the pre- or perioperative setting. Recent inadvertent upstaging of this rare malignancy during laparoscopic morcellation of a presumed fibroid has prompted widespread debate among clinicians regarding the safety of current surgical techniques for management of fibroids. This study aims to conduct a systematic review investigating significant diagnostic features in magnetic resonance imaging (MRI) of uterine leiomyosarcomas...
April 12, 2018: International Journal of Technology Assessment in Health Care
https://www.readbyqxmd.com/read/29623539/registration-of-3d-freehand-ultrasound-to-a-bone-model-for-orthopedic-procedures-of-the-forearm
#14
Matija Ciganovic, Firat Ozdemir, Fabien Pean, Philipp Fuernstahl, Christine Tanner, Orcun Goksel
PURPOSE: For guidance of orthopedic surgery, the registration of preoperative images and corresponding surgical plans with the surgical setting can be of great value. Ultrasound (US) is an ideal modality for surgical guidance, as it is non-ionizing, real time, easy to use, and requires minimal (magnetic/radiation) safety limitations. By extracting bone surfaces from 3D freehand US and registering these to preoperative bone models, complementary information from these modalities can be fused and presented in the surgical realm...
April 5, 2018: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/29621414/magnetic-field-direction-differentially-impacts-the-growth-of-different-cell-types
#15
Xiaofei Tian, Dongmei Wang, Meng Zha, Xingxing Yang, Xinmiao Ji, Lei Zhang, Xin Zhang
Magnetic resonance imaging (MRI) machines have horizontal or upright static magnetic field (SMF) of 0.1-3 T (Tesla) at sites of patients and operators, but the biological effects of these SMFs still remain elusive. We examined 12 different cell lines, including 5 human solid tumor cell lines, 2 human leukemia cell lines and 4 human non-cancer cell lines, as well as the Chinese hamster ovary cell line. Permanent magnets were used to provide 0.2-1 T SMFs with different magnetic field directions. We found that an upward magnetic field of 0...
April 5, 2018: Electromagnetic Biology and Medicine
https://www.readbyqxmd.com/read/29614554/-effect-of-foam-sclerotherapy-for-the-treatment-of-oropharyngeal-venous-malformation
#16
C Q Niu, H Jiang, S Y Zhou, G Shen, H B Li, J Zhang
Objective: To evaluate the safety and efficacy of foam sclerotherapy with polidocanol for the treatment of venous malformation in the oropharynx. Methods: The clinical data of 21 children with venous malformation in the oropharynx treated by foam sclerotherapy were retrospectively analyzed. There were 10 males and 11 females, ranging in age from 1 month to 13 years, with a median age of 2.3 years. MRI was performed in all children, and the diagnosis was further confirmed by radiography. After general anesthesia, the oropharynx was exposed by opening device...
March 7, 2018: Zhonghua Er Bi Yan Hou Tou Jing Wai Ke za Zhi, Chinese Journal of Otorhinolaryngology Head and Neck Surgery
https://www.readbyqxmd.com/read/29609452/experiences-of-magnetic-resonance-imaging-scanning-in-patients-with-pacemakers-or-implantable-cardioverter-defibrillators
#17
Donghoon Han, Si-Hyuck Kang, Youngjin Cho, Il-Young Oh
Background/Aims: Despite the U.S. Food and Drug Adminstration approving a magnetic resonance imaging (MRI)-conditional pacemaker system in 2011, many physicians remain reluctant to perform MRI scanning in patients with cardiac implantable electronic devices. Herein, we aimed to evaluate the real-world safety of MRI in these patients. Methods: This single-center retrospective study examined the interrogation data and outcomes of patients with pacemakers or implantable cardioverter defibrillators who underwent MRI...
April 4, 2018: Korean Journal of Internal Medicine
https://www.readbyqxmd.com/read/29605700/stereoelectroencephalography-guided-radiofrequency-thermocoagulation-for-hypothalamic-hamartomas-preliminary-evidence
#18
Peng-Hu Wei, Yang An, Xiao-Tong Fan, Yi-He Wang, Yan-Feng Yang, Lian-Kun Ren, Yong-Zhi Shan, Guo-Guang Zhao
BACKGROUND: The use of magnetic resonance imaging (MRI)-guided ablation methods, such as laser interstitial thermal therapy and MRI-guided radiofrequency thermocoagulation (RF-TC), poses a risk of mistreatment in patients with nonepileptic hypothalamic hamartoma (HH). Using stereoelectroencephalography (SEEG)-guided RF-TC could solve this problem; however, there are no reports on the efficacy of this technique. Thus, we examined the safety and efficacy of this method. METHODS: This retrospective study was conducted in 9 consecutive patients with HH treated between August 2015 and July 2017...
March 30, 2018: World Neurosurgery
https://www.readbyqxmd.com/read/29605361/combined-nd-yag-laser-and-bleomycin-sclerotherapy-under-the-same-anesthesia-for-cervicofacial-venous-malformations-a-safe-and-effective-treatment-option
#19
Stacie Gregory, Patricia E Burrows, Herodotos Ellinas, Michael Stadler, Robert H Chun
INTRODUCTION: Extensive cervicofacial venous malformations (VM) pose significant challenges to a patient's quality of life (altered breathing, dysphagia, dysarthria). Treatment options include: 1) Surgical debulking; 2) Sclerotherapy; 3) laser therapy; or 4) Combined modalities. Recent studies have demonstrated the importance of multimodality and multidisciplinary management of these patients. However, no studies have described combined single anesthetic laser and sclerotherapy treatment...
May 2018: International Journal of Pediatric Otorhinolaryngology
https://www.readbyqxmd.com/read/29605121/an-audit-of-clinical-practice-referral-patterns-and-appropriateness-of-clinical-indications-for-brain-mri-examinations-a-single-centre-study-in-ghana
#20
A D Piersson, G Nunoo, P N Gorleku
INTRODUCTION: The aim of this study was to investigate current brain MRI practice, pattern of brain MRI requests, and their appropriateness using the American College of Radiology (ACR) Appropriateness Criteria. MATERIAL AND METHODS: We used direct observation and questionnaires to obtain data concerning routine brain MRI practice. We then retrospectively analyzed (i) demographic characteristics, (ii) clinical history, and (iii) appropriateness of brain MRI requests against published criteria...
May 2018: Radiography
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