20 % of all intracranial tumours . Magneticresonanceimaging (MRI) is the modality of choice for the investigation of meningiomas, providing superior contrast differentiation and usually the ability to differentiate between intra- and extra-axial lesions. In addition to MRI, computed tomography (CT) has a useful role in specific cases where there is calcifi- cation and adjacent changes to the calvarium. Although typ- ical meningiomas have characteristic imaging features, there are multiple atypical variants that may be diagnostically chal- lenging and the value of MRI in predicting WHO grades in meningiomas is limited. A number of benign and malignant pathologies may also mimic some of the features of meningi- omas. It is important for the radiologist to have an understand- ing of the typical and atypical features of meningiomas to aid their recognition and suggestion of a correct diagnosis. The typical and atypical imaging appearance of meningiomas is discussed.
Due to their well-differentiated nature, pineocytomas can be indistinguishable from the normal pineal parenchyma. They are well-circumscribed and unencapsulated tumours that arise and expand from the pineal gland, producing the characteristic “explosion” of normal pineal calcifications towards the periphery (Fig. 1) . On magneticresonanceimaging (MRI), pineocytomas usually have low to interme- diate signal on T1-weighted images and intermediate to high signal on T2-weighted images (Fig. 2). These lesions typi- cally show prominent contrast enhancement (Fig. 2). Occa- sionally cystic or partially cystic pineocytomas are seen, which demonstrate internal or nodular wall enhancement on post-contrast imaging [10, 11]. Pineal apoplexy can occur in rare circumstances.
MagneticResonanceImaging (MRI) is a safe and painless way for your doctor to look at your abdomen and small intestines. The test uses radio waves and a magnetic field to take pictures. The pictures can help your doctor find out more about the problems you are having.
Safe Considerations in Magnetic Resonance Imaging (MRI) Safe Considerations in M Imaging (MRI) agnetic Resonance BJ J Abdullah, FRCR, SI Bux, MRad & D Chien*, PhD, Department of Radiology, University[.]
Thank you for your interest in the Mills-Peninsula MRI Technologist Program. This program for registered technologists (radiographers) is a full-time course of study and takes place over a period of 34 weeks. The program is offered every 7-8 months. The curriculum encompasses all principles of magneticresonanceimaging technology and includes 173 hours of didactic instruction and 640 hours of supervised clinical experience. The program is based on the parameters suggested by the Joint Review Commission on Education in Radiologic Technology (JRCERT), the Association of Educators in Radiological Sciences (AERS), and the American Society of Radiologic Technologists (ASRT).
Background: The Lisfranc joint has complex structures, and articular surfaces overlap on conventional X-ray radiographs. Hence, there is no available auxiliary examination for diagnosing related injuries. At present, few studies on the imaging of Lisfranc ligaments have been reported, and related imaging data are rare. Therefore, no imaging reference can be used for related diagnosis and repair operations. This study aims to observe and describe the morphology and structure of Lisfranc ligaments using magneticresonanceimaging (MRI), in order to provide imaging reference for the diagnosis and repair of Lisfranc joint injuries.
Case presentation: We encountered a 48-year-old man who presented with HS in the summer season. During admission, he had a high body temperature and was in coma and shock. Then, he developed rhabdomyolysis syndrome, acute kidney and liver damage, electrolyte imbalance, and acid – base balance disorders, and his D- dimer level was elevated. After several days of anti-shock treatment, the patient ’ s level of consciousness improved. However, he experienced a decline in vision. Cerebral magneticresonanceimaging (MRI) showed symmetrical lesions in the bilateral posterior limb of the internal capsule, putamen, external capsule, insula, and subcortical white matter, and cerebral magneticresonance venography (MRV) showed the development of CVT. Therefore, anti-coagulation treatment was provided. After timely clinical intervention, the symptoms of the patient gradually improved.
This article discusses the basic concepts of MagneticResonanceImaging (MRI) with the intention to introduce the subject to uninitiated. The MRI technique is a powerful noninvasive probe of the body’s internal anatomy. In MAI, the images are produced not by X-rays, but through the use of non-ionizing radio waves that stimulate transitions between spin states of nuclei in a magnetic field when passed through the body. The time required for the nucleus to return to equilibrium gives information about the environment of that nucleus. In this way tissue abnormalities can be determined in vivo. This article covers the basis of MRI phenomena, the concept of magnetic moment of the sample, NMR exalation and emission and the equipment necessary to observe these NMR properties. The primary agents used to increase tissue contrast in MRI are also mentioned. Finally the importance and prospects of this technique in Pakistan have been discussed (JPMA 41: 259, 1991).
Objective: To make effective comparison between the images of magneticresonanceimaging (MRI) is stroke is superior to computed tomography for the diagnosis of acute ischemia. To make effective analysis and comparison between the patients to treated the stroke with rt-PA and not treated with rt-PA. To explore the role advanced neuro-Imaging in acute stroke treatment. Methods: The Present study was conducted with 70 patients, age between 18years and above presenting to emergency department of Uppal neuro hospital Amritsar Punjab with a history of acute ischemic from October 2018 to March 2019. All patients were examined using 32 slices CT and 1.5T MRI Scanner also. Results: acute ischemic stroke patients caused by various reasons like acute ischemic stroke caused by high blood pressure (HBP) 65.0%, and diabetes (DIA) 20.0%,over weight 8%,heart disease 5% in above 70 case. Conclusion: acute ischemic stroke leading cause of death and disability worldwide, especially young adults and lifelong disability is common in those who survive. MRI and CT is well characterized of the extent and various types of stroke and hemorrhages in AIS patients. The present study data is indicated 65.0 % majority of AIS patients is suffered by high blood pressure and high sugar and alcoholism. To make effective analysis and comparison between the patients to treat the stroke with t-PA and not treat with t-PA. There is a role between advanced imaging in acute stroke treatment
Some of the first images of the body produced with magneticresonanceimaging (MRI) were of the breast . However, by the mid-1980s most investigators had concluded that there was little clinical utility for MRI in detecting or diagnosing breast cancer. The application of contrast agents to breast imaging, first published by Heywang and colleagues , changed that thinking and revealed that breast cancers, in comparison with normal breast tissue, were enhanced significantly with standard gadolinium contrast agents. Heywang’s reports were followed closely by those of Kaiser and Zeitler , who also found contrast-enhanced magneticresonance images useful in breast cancer diagnosis but by using a very different technique. Whereas Heywang and colleagues acquired one pre-contrast and two post-contrast sequences of a single breast, permitting high spatial resolution with a three-dimensional gradient echo technique, Kaiser and Zeitler obtained one pre-contrast and multiple post-contrast images of both breasts, permitting high temporal resolution.
Background: Magneticresonanceimaging is one of the diagnostic tools that uses magnetic particles as contrast agents. It is noninvasive methodology which provides excellent spatial resolution. Although magneticresonanceimaging offers great temporal and spatial resolution and rapid in vivo images acquisition, it is less sensitive than other methodologies for small tissue lesions, molecular activity or cellular activities. Thus, there is a desire to develop contrast agents with higher efficiency. Contrast agents are known to shorten both T1 and T2. Gadolinium based contrast agents are examples of T1 agents and iron oxide contrast agents are examples of T2 agents. In order to develop high relaxivity agents, gadolinium or iron oxide-based contrast agents can be synthesized via conjugation with targeting ligands or functional moiety for specific interaction and achieve accumulation of contrast agents at disease sites.
Cardiomyopathy is a frequent cause of early mortality in Alström patients. While the syndrome remains incom- pletely understood, consistent findings were found throughout this patient group, which may give insights into the underlying cardiac pathology. There was no fluid or fatty infiltration of the myocardium in any patient and all displayed patchy left and right ventricular fibrosis and impaired left and right ventricular function, to varying degrees. Cardiac magneticresonanceimaging not only provides pathological insights, but gives the opportunity to detect early functional changes, track the natural his- tory and progression of the disease, and assess the influ- ence of therapeutic interventions, as well as guide referral for transplantation in this challenging group.
Initial experiments outlined in this work illustrate the feasibil- ity of using plasmas for magneticresonance, even with very simple fluorescent tubes. The efficiency of the current plasma setup is much lower than that of an equivalently-sized copper conductor element. However, this is unsurprising given that an off-the-shelf lighting tube has been used as the plasma element. Significant improvements in the plasma performance can be anticipated if a custom-built tube is manufactured. The diameter of the tube can be reduced substantially reducing the power required to ionize the gas, and the gas pressure can also be adjusted. If the plasma pressure and electron density are increased then the plasma cur- rent increases, but the collision frequency increases which increases losses in the plasma, and so a compromise would have to be determined. Alternative plasma sources such as cold cathode fluorescent lamps (CCFLs) may be more appropriate since they do not require electrode heating to form the plasma. The geometry of the tube can also be improved: in the current implementation the plasma tube is fed from one end, effectively producing an electrical monopole. Symmetric central feeding of a two-tube element in a ‘‘dipole arrangement” would produce a field more suitable for MRI. Finally, a more efficient surfatron can certainly be designed, since in the current configuration only a small fraction of the elec- tric field passes through the plasma: for example Fig. 4a shows that at input powers up to " 100 W, the plasma is not fully ignited.
Seven per cent of the MRI examinations analysed in our study were inappropriate. In another study of 3,367 hospitals, the use of outpatient imaging varied widely, possibly indicat- ing overuse. Low imaging volume, a rural setting, for-profit ownership and non-teaching hospitals were more likely to report the highest use. Lack of details about patients ’ clinical data was reported to be one of the limitations of the study . Another report concerning outpatient CT and MRI scans revealed a 70-fold difference between hospitals in the frequen- cy of scans ordered for a specific indication . There was also a study about outpatient MRIs at a university hospital referred by primary care physicians. It revealed 23 per cent of the 175 examinations to be inappropriate. Most of the inap- propriate examinations were in the group of shoulder and lumbar spine MRIs . In another study, referrals for MRI examinations from various hospitals and clinics performing MRI in the area of Stockholm, Sweden, were surveyed. Nine per cent of the MRIs were deemed inappropriate .
played out between excitation and acquisition of the NMR signal, before the signal has completely decayed . Approximately 70% of the body comprises water, and 99.98% of naturally occurring hydrogen nuclei are the 1 H isotope. 1 H also has the highest NMR sensitivity of any nucleus , so clinical MRI usually images 1 H nuclei in water molecules. 1 H nuclei in macromolecular structures or in membranes can also be imaged indirectly using magnetization transfer techniques or directly at higher magnetic field strengths, using special MRI acquisition protocols. Nuclei found in low concentrations in the human body can be imaged using MRI techniques if a compound containing those nuclei can be introduced as a contrast agent in the region of the body that needs to be imaged. These MRI imaging techniques can be used for specific targeting and cellular imaging to evaluate response to therapies. Such an example is that of fluorine ( 19 F) MRI. The 19 F nuclei exist in high concentrations in the bone and teeth but in concentrations below the MRI detection limit in normal wet tissue. The lack of any background signal from most of the body provides 19 F MRI with a potentially extremely high contrast-to-noise ratio and specificity. The 19 F nucleus has a 100% natural abundance and resonates at a frequency that is 94% of that of 1 H. Its NMR sensitivity is 83% of that of 1 H, its SNR being about 89% of 1 H per nucleus. For 19 F MRI to produce an image quality similar to that of 1 H MRI, the agent requires a high density of 19 F nuclei in the molecule in addition to a high concentration of the molecule in the tissue of interest .
resonanceimaging (MRI), and magneticresonance spec- troscopy (MRS) have been widely used to monitor struc- tural, functional, and molecular changes in cancer tissues both clinically and pre-clinically [2–12]. PET and SPECT use radiotracers to image and measure the biological activity at targeted site, and are generally considered as molecular imaging modalities. However, despite exqui- site sensitivity they are beset by poor resolution and the application of nuclear radiation may preclude their use for repetitive measurements in a short time period. Opti- cal imaging has been used to image specific molecular features of cancer by employing molecular targeted con- trast agents [7, 13]. Studies have suggested that optical based method can provide early information of treatment efficacy [14, 15]. However, requirement of the optical probe insertion in tissue limits its repetitive use, and also it is not suitable for studying parts of tissue that are dis- tant from the probe.
to microhaemorrhages, may reveal brain microhaem- orrhages in patients with cerebral malaria [10, 11]. Imported malaria differs from malaria cases in endemic regions regarding several aspects. Affected patients are mainly adults with no or waning prior anti-malarial immunity . Asymptomatic chronic parasitaemia is rare, as are coinfections such as bacteraemia and nutri- ent deficiencies . Due to the absence of these factors, returning travellers with malaria form a more homogene- ous population in which to investigate cerebral involve- ment by magneticresonance imagin (MRI) without a confounding effect.
Magneticresonanceimaging (MRI) is a modality capable of providing excellent contrast for soft tissues, yet it provides very little information about bone, which, by contrast, can be seen clearly in CT images. This project attempts to remedy this limitation by expanding the visualisation capability of MRI to include details of skull boundary. The potential benefits of this advance include the accurate co-registration of MRI and CT or MRI and MRI image data, as used in frameless surgery planning; the avoidance of harmful radiation, a problem encountered in CT skull visualisation; modelling of electrical conductivity in the head; and cranioplasty planning. In addition, the method developed wiU potentially be helpful for the measurement of brain volume, especially small changes in voxel size, which is used in the quantitative assessment of changes in neurological diseases. Skull edge detection is made difticult due to the partial volume effect, strong edges between muscle and scalp, the thin appearance of the skull in the temporal region and strong edges near the superior sagittal sinus.