Clinical Applications Of Functional MRI Research Articles

Neurofunctional and microstructural features of the brain in patients with nutritional obesity according to special magnetic resonance imaging techniques (literature review)

Background. Obesity is a chronic disease characterized by excessive accumulation of adipose tissue in the body, manifested by an increase in body weight by 20 percent or more of the average values. Obesity is becoming an increasingly significant public health problem. Assessment of the functional pathology of the brain provides more information about the pathogenetic changes leading to metabolic disorders. Modern methods of neuroimaging make it possible to obtain information about the initial functional changes in the brain according to the data of intracerebral connectivity - functional connectivity between its individual structures.Objective. The study of modern literature data on functional disorders of brain connectivity in patients with obesity, including those with eating disorders.Materials and methods. A systematic review of studies published in foreign and domestic literature has been carried out. Articles were searched using the PubMed database and Elibrary.Results. The problem of functional and microstructural studies of the brain in obesity is covered in sufficient detail in Western English-language literature. Nevertheless, it must be stated that at the moment there are practically no articles on the subject under study in domestic scientific publications. However, it should be noted that in the foreign literature there are rare data on neuroimaging of the brain in the aspect of neural network connectivity, studies in obesity with concomitant somatic pathology, for example, in type II diabetes, and other disorders of the endocrine system. There are relatively few data where correlations would be made with the age and gender of patients, concomitant mental disorders, which emphasizes the relevance of the issue.At the subsequent stages of the joint development of endocrinology, psychiatry and radiation diagnostics, the use of modern MRI techniques will help with the choice of target structures for stereotaxic correction of the described pathology. The clinical application of functional MRI will help to reveal the pathogenesis of various types of obesity at the neurofunctional levels with further prediction and analysis of the development of the disease, while the inconsistency and inconsistency of the currently obtained results of studies of the pathogenesis of alimentary obesity in terms of the pathology of functional connectivity based on fMRI, the absence clinical application of special MRI techniques substantiate the need to continue scientific research in this direction

Progress of clinical application of functional MRI in the localization of brain language area

For surgical operation in the functional area in the brain, it's commonly demanded to resect the lesion to the maximal extent on the basis of preserve the normal neural function, thus the precise localization of functional area is extremely important. As for the advantages of being widely available, easy to grasp and non-invasive, the functional MRI (fMRI) has come into wide use, while the application of language fMRI is still in the initial stage. It's important to choose appropriate fMRI task according to the individual condition of the subject, the commonly-adopted tasks include verb generation, picture naming, word recognition, word generation, etc. However, the effectiveness of using fMRI to localize language area is not totally satisfactory, adopting multiple task is an effective approach to improve the sensitivity of this technique. The application of resting state fMRI in the localization of language area and the further research of the role of fMRI in localizing the Chinese language area are the important future directions.

Clinical applications of functional MRI.

Clinical applications of functional MRI.

Clinical applications of functional MRI in epilepsy

The role of functional MRI (fMRI) in the presurgical evaluation of patients with intractable epilepsy is being increasingly recognized. Real-time fMRI is an easily performable diagnostic technique in the clinical setting. It has become a noninvasive alternative to intraoperative cortical stimulation and the Wada test for eloquent cortex mapping and language lateralization, respectively. Its role in predicting postsurgical memory outcome and in localizing the ictal activity is being recognized. This review article describes the biophysical basis of blood-oxygen-level-dependent (BOLD) fMRI and the methodology adopted, including the design, paradigms, the fMRI setup, and data analysis. Illustrative cases have been discussed, wherein the fMRI results influenced the seizure team's decisions with regard to diagnosis and therapy. Finally, the special issues involved in fMRI of epilepsy patients and the various challenges of clinical fMRI are detailed.

Clinical application of functional MRI for memory using emotional enhancement: Deficit and recovery with limbic encephalitis

Although some functional MRI memory studies show reliable neural activity in the hippocampus and mesial temporal lobe (MTL), most typically report results from group studies. However, fMRI memory probes need to be robust enough to show MTL activity in individual patients to be helpful in diagnosis and treatment planning. We present the case of a patient with non-paraneoplastic limbic encephalitis who had severe anterograde amnesia with subsequent recovery to illustrate a fMRI probe of MTL activity that is easily administered to neurological patients. The task uses emotionally positive and affiliative stimuli to elicit responsivity in the amygdala–hippocampus region. In this patient, weak bilateral hippocampal activation was observed in the acute stage that increased after recovery, paralleling findings on structural MRI and neuropsychological memory assessment. This case study demonstrates that using emotional stimuli to enhance memory responsivity may be an effective way to visualize clinical changes in individual patients.

Functional MR imaging of the female pelvis

Recent developments in MR techniques have magnified the roles and potential of MRI in the female pelvis. This article reviews the techniques and clinical applications of functional MRI (fMRI) of the female pelvis, including cine MRI, diffusion-weighted MRI (DWI), and dynamic contrast-enhanced (DCE)-MRI. Cine MRI is a useful tool for evaluating uterine contractility, including sustained contraction and peristalsis, in a variety of conditions and gynecologic disorders, and for evaluating pelvic-floor weakness. DWI can demonstrate abnormal signals in pathologic foci based on differences in molecular diffusion. It also enables the quantitative evaluation of the apparent diffusion coefficient (ADC), which may be useful for distinguishing malignant from benign tissues and monitoring therapeutic outcome. DCE-MRI has the potential to improve tumor detection and local staging, and can also provide quantitative information about perfusion of the tumor, which may be useful for both monitoring therapeutic effects and predicting therapeutic outcome. Understanding the roles played by functional MR techniques in the female pelvic region is beneficial not only for determining clinical applications, but also for developing further investigations with MRI.

Special Session on Clinical Application of Functional MRI

Special Session on Clinical Application of Functional MRI

Aplicação clínica da RM funcional. Avaliação de funções motoras e fluência verbal.

In this article we reviewed some examples of our experience in clinical applications of functional MRI (fMRI) in the motor and verbal fluency tasks evaluation. Seventeen patients with supratentorial cerebral pathology (5 arteriovenous malformations--AVMs, 2 meningiomas, 1 tuberculoma, 1 cortical tuberoma, 1 DNET, 2 cerebral metastases, 3 gliomas and 2 patients with mesial temporal sclerosis and medically intractable epilepsy--lateralization of language) and three healthy subjects were studied on a 1.5 T system (Signa GE) using a blood oxygen level-dependent (BOLD)--sensitive multi-slice EPI technique. Different paradigms for localization of the motor (hand/foot) and verbal fluency sensorimotor cortex were tested and selected for each pathology. In healthy subjects motor activation elicited BOLD signal changes in the sensorimotor cortex, permitting identification of primary motor and sensory cortical areas and focal activation of different cortical areas by a verbal fluency task. Twelve motor studies were performed and in 6 RMF results demonstrated the localization of motor hand areas near the lesion, and in nine studies of verbal fluency 6 activation were adjacent to the lesion. The studies were performed prior to neurosurgical procedures, contributed to therapeutical decisions and proved to be a valuable non invasive method of cortical mapping for preoperative planning.

Prospects for progress in diagnostic imaging

Abstract. Potchen EJ (Michigan State University, Michigan, USA). Prospects for progress in diagnostic imaging (Internal Medicine in the 21st Century). J Intern Med 2000; 247: 411–424.New fast‐imaging MRI systems designed specifically for cardiac magnetic resonance enable new applications of noninvasive vascular imaging. The use of functional MRI and diffusion tensor imaging to map brain function and structure offers a new dimension to an understanding of the human condition. Clinical applications of functional MRI will influence many specialties including surgery, education, and rehabilitation. Functional imaging has the potential to visualize the regional concentration of specific proteins. This imaging at the level of molecules may be possible by use of a contrast material whose signal is changed by local enzymatic activity.The three‐dimensional digital data collected in modern imaging techniques allow for virtual endoscopy in the respiratory, alimentary, and cardiovascular systems. Virtual endoscopy may replace many of the more invasive diagnostic methods in the near future. The measurement of clinical decision‐making through observer performance studies better informs both the physician and the patient on how to improve upon the quality of clinical practice. These prospects for progress reinforce diagnostic imaging as a cornerstone in medical informatics. The history of creating images used in medicine reveals the invention of diagnostic tools which may provide new information but premature use can result in improper application of a poorly understood technology. Research into the use of new technology may be as important as the technology itself in improving the human condition.

Basic Principles and Clinical Application of Functional MRI

Basic Principles and Clinical Application of Functional MRI

Functional MRI: Background and clinical applications

Functional MRI is gaining wider acceptance as a clinical tool that can be used for a variety of clinical indications. The goal of this article is to introduce the reader to functional MRI as a technique and present some clinical applications of functional MRI.

Prospects for progress in diagnostic imaging.

New fast-imaging MRI systems designed specifically for cardiac magnetic resonance enable new applications of noninvasive vascular imaging. The use of functional MRI and diffusion tensor imaging to map brain function and structure offers a new dimension to an understanding of the human condition. Clinical applications of functional MRI will influence many specialties including surgery, education, and rehabilitation. Functional imaging has the potential to visualize the regional concentration of specific proteins. This imaging at the level of molecules may be possible by use of a contrast material whose signal is changed by local enzymatic activity. The three-dimensional digital data collected in modern imaging techniques allow for virtual endoscopy in the respiratory, alimentary, and cardiovascular systems. Virtual endoscopy may replace many of the more invasive diagnostic methods in the near future. The measurement of clinical decision-making through observer performance studies better informs both the physician and the patient on how to improve upon the quality of clinical practice. These prospects for progress reinforce diagnostic imaging as a cornerstone in medical informatics. The history of creating images used in medicine reveals the invention of diagnostic tools which may provide new information but premature use can result in improper application of a poorly understood technology. Research into the use of new technology may be as important as the technology itself in improving the human condition.

Magnetic resonance in the assessment of renal function.

The kidneys are the most important organs to maintain homeostasis. In the assessment of renal functional disorders laboratory tests offer only indirect hints on location of the disease; radionuclide nephrography is hampered by low spatial resolution and radiologic methods provide only limited quantitative information. The MRI technique with fast pulse sequences and renally eliminated contrast agent has the capability of combining both anatomic and functional information. This article gives an overview on functional MRI of the kidneys with its possibilities and limitations. The clinical application of functional MRI allows a better understanding of some pathologic conditions such as urinary tract obstruction, renal insufficiency, effects of extracorporeal shock wave lithotripsy, different states of hydration, effects of drugs, vascular disorders, and effects of transplantation.

Clinical applications of functional MRI in neuropsychiatry.

Clinical neuroimaging is due for yet another sea change as functional neuroimaging becomes increasingly powerful and available. Functional magnetic resonance imaging (fMRI) is perhaps the most promising of the emerging techniques. The following review helps us understand the physics, strengths, limitations, and promise of fMRI. The authors are all affiliated with the Brain Imaging Center at McLean Hospital and with the Departments of Neurology (Dr. Levin) and Psychiatry (Dr. Renshaw) at Harvard Medical School.

L-2 Clinical applications of functional MRI

Categorical encoding is crucial for mastering large bodies of related sensory-motor experiences, but what is its neural substrate? In an effort to respond to this question, recent single-unit recording studies in the macaque lateral prefrontal cortex (LPFC) have demonstrated two characteristic forms of neural encoding of the sequential structure of the animal’s sensory-motor experience. One population of neurons encodes the specific behavioral sequences. A second population of neurons encodes the sequence category (e.g. ABAB, AABB or AAAA) and does not differentiate sequences within the category (Shima, K., Isoda, M., Mushiake, H., Tanji, J., 2007. Categorization of behavioural sequences in the prefrontal cortex. Nature 445, 315–318.). Interestingly these neurons are intermingled in the lateral prefrontal cortex, and not topographically segregated. Thus, LPFC may provide a neurophysiological basis for sensorimotor categorization. Here we report on a neural network simulation study that reproduces and explains these results. We model a cortical circuit composed of three layers (infragranular, granular, and supragranular) of 5 * 5 leaky integrator neurons with a sigmoidal output function, and we examine 1000 such circuits running in parallel. Crucially the three layers are interconnected with recurrent connections, thus producing a dynamical system that is inherently sensitive to the spatiotemporal structure of the sequential inputs. The model is presented with 11 four-element sequences following Shima et al. We isolated one subpopulation of neurons each of whose activity predicts individual sequences, and a second population that predicts category independent of the specific sequence. We argue that a richly interconnected cortical circuit is capable of internally generating a neural representation of category membership, thus significantly extending the scope of recurrent network computation. In order to demonstrate that these representations can be used to create an explicit categorization capability, we introduced an additional neural structure corresponding to the striatum. We showed that via cortico-striatal plasticity, neurons in the striatum could produce an explicit representation both of the identity of each sequence, and its category membership.