View clinical trials related to MRI.
Filter by:A magnetic resonance imaging (MRI) examination usually takes 30 to 45 minutes and requires the patient to remain perfectly still during the entire acquisition process to ensure quality. Children under 6 years of age are not very cooperative and sedation is required for this age group. Currently, there are no specific recommendations for sedation for a paediatric MRI examination. In 2018, a retrospective study on the sedation protocol applied at Hôpital Universitaire des Enfants Reine Fabiola (H.U.D.E.R.F.) was conducted. In this protocol, premedication was done with oral midazolam and sedation with iterative boluses of propofol. This study concluded that the protocol in place was effective, but found that image acquisition during the procedure was interrupted in 25% of cases, largely due to involuntary movements of the child. Preoperative stress can be emotionally traumatic for the child and may even extend beyond the perioperative period, hence the importance of premedication. For the most anxious children, non-pharmacological means of premedication are often not sufficient. Moreover, the literature shows that pharmacological premedication is useful in reducing parental separation anxiety and in facilitating induction of anaesthesia. Midazolam is an effective premedication agent with some disadvantages (paradoxical reaction, low compliance of oral intake). Dexmedetomidine is a highly effective α-2 receptor agonist that can also be used as premedication according to the current literature. A report by the Pediatric Sedation Research Consortium (P.S.R.C.) shows that it has a safe profile and an incidence rate of serious adverse events of 0.36% in the paediatric population. Furthermore, administered intranasally, it is non-invasive, painless and has good bioavailability (over 80%). The primary objective is to demonstrate the superiority of intranasal dexmedetomidine over oral midazolam as a premedication for bolus sedation of propofol in terms of the incidence of any event during the MRI procedure requiring temporary or permanent interruption of the examination. The impact of dexmedetomidine on the amount of propofol administered and on the post-sedation period, the impact of external factors on the primary objective, the acceptance of intranasal premedication by the children and the quality of the MRI images will also be analyzed.
Metastatic disease to the bone is a common cause of pain. External beam radiation therapy (EBRT) is the standard palliative treatment BUT pain improvement is observed in 60% to 80%. Combination of hyperthermia (HT) with radiation is strongly compelling. MR is providing accurate, tissue-independent thermometry for intra-procedural guidance of thermal therapy. In this project we aim to combine in an adjuvant setting mild hyperthermia to EBRT for sustained relief of pain in patients with symptomatic bone metastases.
Optimization of magnetic resonance imaging (MRI) protocols on healthy volunteers and voluntary patients. In MRI, a large number of technical parameters (sequence, parameters in sequence, antenna, reconstruction method, etc.) can be changed to optimize the diagnostic quality of the exam. Some optimizations can be performed on participants healthy volunteers, others need to be carried out on images pathological and acquired in voluntary patients.
Since January 2010, a new magnetic resonance imaging scanner (Philips 3T, Achieva) is installed on the Baudot Building in Toulouse hospital. This tool, is completely dedicated to the research. It was installed with sequences RMN supplied by the manufacturer. Imagers also contain an instrumentation susceptible to evolution and/or to adjustment (antennas radio frequency, sheath of gradients, elements of physiological monitoring (for example control of the breath), regulation of the homogeneity of the magnetic field). This MRI scanner and this instrumentation are used for anatomical examinations or for paradigms of cognitiveresearch (for example of detection of intellectual activations following simple stimuli of fingers movement, visual tasks, or of mental processes). The developpement of this equipment is going to favor the emergence of numerous projects and new themes, up to there adressed by other techniques (psychophysics, EEG). To obtain good quality signals and know the practical limits of this imager, it is thus necessary that the researchers doctors, physicists and engineers, can finalize on volunteers' significant number, all the sequences RMN necessary for the use of these tools for the research. These developments are going to get organized around four main axes: 1 the control of the geometrical distortions (generated by the introduction of an object within the magnetic field) 2 Optimization of the parameters of sequences to improve the contrast and the spatial resolution of the obtained images 3 the development of new sequences 4 the feasibility study of the protocols of functional MRI
IRMaGe is a Joint Service Unit (UMS) which provides users of brain exploration equipment (clinical MRI and preclinical, TMS, EEG, NIRS and metabolomics). The methods available on this equipment are intended to evolve according to the most recent discoveries and this protocol aims to frame the developments necessary around clinical MRI for IRMaGe can continue to offer tools at the cutting edge of technology.
Crohn's disease (CD) is a chronic inflammatory bowel disease (IBD) that can dramatically affect the quality of life of patients. Due to its transmural nature (involvement of the entire thickness of the intestinal wall), it naturally progresses to intestinal destruction (stenosis, fistula) which requires intestinal resection in approximately half of patients during their follow-up. The long-term goal for patients is to maintain a normal life, that is, without symptoms and without intestinal destruction. For this, the short and medium term therapeutic objectives have evolved in recent years. Clinical remission is not a sufficient goal since it has failed to alter the natural history of the disease. The current objective to be achieved is the combination of clinical remission and endoscopic mucosal healing since it is associated with a reduced risk of progression (reappearance of symptoms, hospitalization, intestinal resection). Fecal calprotectin, better accepted than colonoscopy, is a non-invasive biomarker of endoscopic inflammatory activity in CD. The CALM study recently showed that close follow-up with clinical and biological evaluation (assays of CRP and fecal calprotectin), called "tight control", associated with therapeutic intensification in the absence of clinical or biological remission, was associated with a better rate of endoscopic mucosal healing at 1 year than follow-up based solely on symptoms. Thus, the "CALM" strategy is considered to be the current benchmark. Transmural healing evaluated by MRI is also a promising objective associated with a reduced risk of progression (reappearance of symptoms, hospitalization, bowel resection). In addition, it could prevent intestinal destruction. A recent study by our team suggested that calprotectin (mucosal assessment) and MRI (transmural assessment) may be complementary and be a better therapeutic goal. We hypothesize that a "CALM + MRI" strategy concomitantly targeting transmural healing would be superior to the "CALM" strategy alone in maintaining clinical remission without corticosteroids in patients with CD treated with biotherapies.
3 d scan sequence can realize continuous thin layer scanning, the thinnest layer thickness of 0.5 mm, to reduce the effects of partial volume effect and improve the spatial resolution image, the other 3 d sequence can according to need to multiplanar reconstruction based on the original image, the image of the watch is no longer limited to a fixed plane, and can avoid repeated scanning, reducing overall inspection time. Initially, 3D MRI uses gradient echo sequences (3D-GRE). Although the scan time of 3D-GRE is acceptable and has a high spatial resolution, the contrast between tissues is poor. In recent years, is voxel 3D fast spin-echo sequence (3D-FSE) has become an alternative 3D scanning sequence. Compared with the 3D-GRE sequence, 3D-FSE has better-intertissued contrast. However, there are still some problems in the application of 3D sequence in clinical practice. On the one hand, although 3D sequence reduces the overall scanning time, it increases the single scanning time, so it is easy to produce motion artifacts. On the other hand, although many studies have demonstrated the diagnostic efficacy of 3D sequences in the diagnosis of common intraarticular structural injuries, especially in the diagnosis of knee cartilage injuries, the diagnostic value of 3D sequences is comparable to that of conventional 2D-FSE sequences, but the evidence on whether 3D sequences can replace 2D sequences is still insufficient. Recently, a new fast signal acquisition technology -- Compressed Sensing (Compressed Sensing) technology has been gradually applied to many kinds of MRI sequences, and its application in 3D sequences can greatly shorten the single scan time. In this study, Modulated Flip Angle Technique in Refocused Imaging with Extended Echo was applied by United Imaging Co., Ltd. (Compressed Sensing) Train, 3D-Matrix), which is a fast self-selected echo sequence based on variable turn Angle technology, and its single scan time can be shortened to 5 minutes. 3 d sequence to more systematic evaluation on sports injury of knee joint application value, the investigators will study from within the bony structure of knee joint injury, joint structure damage and injury of the surrounding support structure aspects to discuss the diagnosis effect, and with arthroscopy for the gold standard to evaluate the accuracy of the 3 d structure within the sequence in the diagnosis of knee joint injury.
Patients who have agreed to participate in the study will complete the MRI protocol as part of routine care, to which a maximum of four additional 25-minute sequences will be added. MRI of routine care includes at least the following sequences: - 3D T1 TFE (2 minutes) - T2 TSE (2 minutes) - 3D FLAIR (3 minutes) The sequences added by the research lasting 25 minutes are: - SWI QSM 1.0iso 8 echoes (10 minutes) - SWI QSM 1.0iso 8 echoes CS 6 (7 minutes) - SWI QSM 1.0iso 8 echoes CS 9 (5 minutes) - SWI QSM 1.0iso 8 echoes CS 12 (3 minutes)
This is a phase II randomized trial, where patients with histologically proven squamous cell carcinoma of oropharynx that have primary tumor (T3 - T4) in place, treated with curative intent chemoradiation, will be randomized to systematic mid-treatment MRI-based radiotherapy adaptation vs. standard of care. The primary objective is to compare patient-rated dysphagia (as assessed by the MD Anderson Dysphagia Inventory composite score at 6 months post-treatment in patients undergoing routine mid-treatment MR-guided radiotherapy adaptation vs. in patients receiving the current standard of care.
About 20 to 30% of patients treated for cancer will have brain metastases. These brain metastases are found more frequently in patients with lung cancer, breast cancer or melanoma. The prognosis of these patients is unfavorable but prolonged survival can be obtained with the local and systemic treatments currently available. Brain MRI is the gold standard for evaluating brain metastases but has limitations in therapeutic evaluation, partially offset by PET imaging of amino acid metabolism. Our work aims to compare the performance of PET-DOPA with standard MRI for the detection of brain metastases (≥ 5mm) in lung cancer, breast cancer and melanoma; and to characterize these lesions using dynamic acquisitions obtained with a digital PET camera with high spatial resolution. Having better knowledge of the metabolic characteristics of newly discovered brain metastases, the objective of subsequent studies will be to better assess the per- or post-therapeutic efficacy of radiotherapy and the various systemic therapies available (chemotherapy, targeted therapy, immunotherapy).