Search results for "Resonance"
showing 10 items of 6625 documents
Video-Assisted Navigation for Adjustment of Image-Guidance Accuracy to Slight Brain Shift
2015
Background Information supplied by an image-guidance system can be superimposed on the operating microscope oculars or on a screen, generating augmented reality. Recently, the outline of a patient's head and skull, injected in the oculars of a standard operating microscope, has been used to check the registration accuracy of image guidance. Objective To propose the use of the brain surface relief and superficial vessels for real-time intraoperative visualization and image-guidance accuracy and for intraoperative adjustment for brain shift. Methods A commercially available image-guidance system and a standard operating microscope were used. Segmentation of the brain surface and cortical bloo…
Can Early Postoperative O-(2-18FFluoroethyl)-l-Tyrosine Positron Emission Tomography After Resection of Glioblastoma Predict the Location of Later Tu…
2019
Objective Glioblastoma inevitably recurs despite aggressive therapy. Therefore, it would be helpful to predict the location of tumor recurrence from postoperative imaging to customize further treatment. O-(2-18Ffluoroethyl)- l -tyrosine (FET) positron emission tomography (PET) might be a helpful technique, because tumor tissue can be differentiated from normal brain tissue with high specificity. Methods Thirty-two consecutive patients with perioperative and follow-up imaging data available were included. On postoperative FET-PET, the tumor/normal brain (TTB) ratio around the resection cavity borders was measured. Increased TTB ratios were recorded and anatomically correlated with the site o…
Rektumkarzinom: Behandeln wir zu häufig neoadjuvant? Vorschläge zu einer selektiveren, MRT-basierten Indikation
2006
The present-day optimised surgery (concept of total mesorectal excision) with quality assurance by standardized pathologic examination, advances in radiotherapy and the possibilities of high-spatial-resolution MR imaging require reconsideration of pros and contras of neoadjuvant therapy and respective data. According to the resulting new proposal neoadjuvant long-course radiochemotherapy is indicated for patients with 1) fixed questionably R0 resectable tumors, 2) mobile tumors with the MRT finding of tumor involving the mesorectal fascia or 1 mm or less from it, 3) low rectal tumors extending below the levator origin and invading beyond the muscularis propria. If a high risk of local recur…
Functional MRI and motor behavioral changes obtained with constraint-induced movement therapy in chronic stroke
2011
Background: The clinical benefits of intensive stroke rehabilitation vary individually. We used multimodal functional imaging to assess the relationship of clinical gain and imaging changes in patients with chronic stroke whose voluntary motor control improved after constraint-induced movement therapy (CIMT). Methods: Eleven patients (37.6 ± 36.8 months from stroke) were studied by functional MRI (fMRI), transcranial magnetic stimulation (TMS), and behavioral assessment of hand motor control (Wolf Motor Function Test) before and after 2 weeks of CIMT. Individual and group-level changes in imaging and behavioral parameters were investigated. Results: Increase in fMRI activation in the sen…
Morphologische und funktionelle Evaluation pulmonaler Gefäßanomalien mittels schneller MR-Techniken
2002
Purpose: To evaluate breath-hold MR techniques for morphologic and functional assessment of vascular abnormalities of the pulmonary vasculature. Patients and Methods: 13 patients aged 11 to 60 years with different vascular abnormalities of the pulmonary vasculature (5 patients with 16 arteriovenous malformations, 8 patients with partial anomalous pulmonary venous return) underwent MR imaging at 1.5 T. For morphological assessment, a contrast-enhanced 3D MR angiography (ce-MRA) was performed after a timing run. Segmented cine- and velocity-encoded GRE sequences were used for delineation of associated cardiac septal defects and for determination of systemic left-to-right or intrapulmonary shu…
The Sum of ST-Segment Elevation Is the Best Predictor of Microvascular Obstruction in Patients Treated Successfully by Primary Percutaneous Coronary …
2010
Introduction and objectives The usefulness of ST-segment elevation resolution (STR) for predicting epicardial reperfusion is well established. However, it is still not clear how ST-segment changes are related to microvascular obstruction (MVO) observed by cardiovascular magnetic resonance (CMR) after primary percutaneous coronary intervention (pPCI) for ST-segment elevation myocardial infarction (STEMI). Methods The study involved 85 consecutive patients admitted for a first STEMI and treated by pPCI who had a patent infarct-related artery. An ECG was recorded on admission and 90 min and 6, 24, 48 and 96 h after pPCI. Thereafter, STR and the sum of ST-segment elevation (sumSTE) in all leads…
Comparative ergonomic workflow and user experience analysis of MRI versus fluoroscopy-guided vascular interventions: an iliac angioplasty exemplar ca…
2014
A methodological framework is introduced to assess and compare a conventional fluoroscopy protocol for peripheral angioplasty with a new magnetic resonant imaging (MRI)-guided protocol. Different scenarios were considered during interventions on a perfused arterial phantom with regard to time-based and cognitive task analysis, user experience and ergonomics. Three clinicians with different expertise performed a total of 43 simulated common iliac angioplasties (9 fluoroscopic, 34 MRI-guided) in two blocks of sessions. Six different configurations for MRI guidance were tested in the first block. Four of them were evaluated in the second block and compared to the fluoroscopy protocol. Relevant…
Transcranial Magnetic Resonance-Guided Focused Ultrasound Surgery for Brain Tumor Ablation: Are We Ready for This Challenging Treatment?
2018
The treatment of high-grade gliomas (HGGs) remains a challenge for modern therapy. The prognosis for these patients has been poor. The median patient survival after diagnosis has been ∼1 year with surgery and/or radiotherapy and temozolomide.1 The need for a histological diagnosis of tumor tissue in each case and the importance of decompression in symptomatic patients are well established, and extensive surgical resection has been shown to significantly prolong survival. Several factors play a role in the prognosis of patients with HGG, including age, performance status using the Karnofsky performance scale, and the extent of resection.2, 3 At present, the standard therapy for HHG consists …
Traumatic lumbar disc extrusion mimicking spinal epidural hematoma: Case report and literature review
2020
Background: Because the neurological presentation of spinal epidural hematomas (SEH) is often not specific, they may be misdiagnosed as acute lumbar disk herniations. Here, we present a case in which a traumatic disc extrusion mimicked an epidural hematoma and reviewed the appropriate literature. Case Description: A 27-year-old male sustained a high-energy fall. The lumbar MRI scan showed a L4-S1 ventral medium/high signal intensity mass on the T1- and high signal intensity lesion on T2-weighted images; the original diagnosis was spinal epidural hematoma. However, at surgery, consisting of a left L4 and L5 hemilaminectomy with L4-L5 and L5-S1 laminotomy, an extruded lumbar disc was encount…
Clinical and radiological outcome of arthrocentesis followed by autologous blood injection for treatment of chronic recurrent temporomandibular joint…
2017
Background This study was conducted to evaluate the functional outcome and MRI findings of arthrocentsis followed by autologous blood injection (ABI) into the joint space for management of chronic recurrent TMJ dislocation. Material and methods Total ten patients with bilateral chronic recurrent condylar dislocation were included in the study. Arthrocentesis of both TMJ was performed on each patient, followed by the injection of 2 ml of autologous blood into the superior joint compartment and 1 ml onto the outer surface of the joint capsule. Preoperative and postoperative assessment included; thorough history, clinical examination of TMJ, maximal mouth opening, frequency of dislocation, TMJ…