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Search Results: 1 - 10 of 12065 matches for " Magnetic Resonance Imaging "
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Lesion contrast differences in MRI sequences in multiple sclerosis: Correlation to clinical disability  [PDF]
Maija Rossi, Minna Raunio, Pertti Ryymin, Irina Elovaara, Prasun Dastidar
Journal of Biomedical Science and Engineering (JBiSE) , 2013, DOI: 10.4236/jbise.2013.63A041
Abstract:

The purpose of this study was to analyze the lesion brightness (image contrast) in multiple MRI sequences in patients with relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), primary progressive MS (PPMS), and clinically isolated syndrome (CIS); and to correlate the lesion contrast with lesion volumes and neurological disability. MRI ex- amination at 1.5 T was performed on 80 patients with RRMS, SPMS, PPMS, or CIS. The protocol included T1- and T2-weighted spin echo (SE), fluid attenuated inversion recovery (FLAIR), T1-weighted SE with magnetization transfer preparation, and diffusion weighted imaging (DWI). Contrast was measured between MS lesions and normal appearing white matter. Lesion volume was calculated in T1-weighted- and FLAIR-images. All patients were examined neurologically including evaluation of expanded disability status scale (EDSS) score. Lesion contrast correlated with total brain lesion volume (p = 0.000 - 0.040). In patients with low EDSS, three sequences were able to differentiate between CIS and RRMS. SPMS and PPMS were separated by DWI. Lesion contrast correlated with EDSS score on T1-weighted imaging, with or without magnetization transfer preparation. Patient age correlated with lesion contrasts. Contrast measurements seem limited in radiological and clinical diagnosis of MS in reference to disease course, its activity and progression. The differentiation between MS subgroups might improve at 3 T and could help in leading to earlier treatment of the disease.

Clinico-radiological dissociation in multiple sclerosis: Future prospects  [PDF]
Elena Zapata-Arriaza, María Díaz-Sánchez
World Journal of Neuroscience (WJNS) , 2013, DOI: 10.4236/wjns.2013.33019
Abstract:

Magnetic resonance imaging (MRI) has significantly contributed to our capabilities of diagnosis multiple sclerosis (MS) since it is able to detect demyelinating lesions in almost 100% of patients. However, there are modest correlations between irreversible disability and white matter lesion load, as measured by T2-weighted MRI scans, which represents the clinicoradiological paradox of MS. We report the case of a patient with MS and few neurological manifestations despite extensive T2 visible morphologic abnormalities. The use of non-conventional MRI techniques, which are more specific in the analysis of the pathological substrate of demyelinating lesions and normal appearing brain matter (both white and gray matter), might assist us to overcome this limitation of conventional MRI.

Functional brain imaging with use of a new and powerful neuroimaging technique  [PDF]
Mohammad Karimi Moridani
Journal of Biomedical Science and Engineering (JBiSE) , 2009, DOI: 10.4236/jbise.2009.23029
Abstract: Most of the information available on the human brain came from subjects who had sustained major head wounds, or who suffered from various mental disorders. By determining the extent of brain damage, and the nature of the loss of function, it was possible to infer which regions of the brain were responsible for which function. With the development of the imaging techniques of computerised tomography (CT) and magnetic resonance imaging it was possi-ble to be more specific as to the location of damage in brain injured patients. The meas-urement of the electrical signals on the scalp, arising from the synchronous firing of the neu-rons in response to a stimulus, known as elec-troencephalography (EEG), opened up new possibilities in studying brain function in nor-mal subjects. However it was the advent of the functional imaging modalities of positron emis-sion tomography (PET), single photon emission computed tomography (SPECT), functional magnetic resonance imaging (fMRI), and mag-netoencephalography (MEG) that led to a new era in the study of brain function. In this paper the mechanisms of the techniques mentioned above are outlined, together with an assess-ment of their strengths and weaknesses. Then an introduction to the Metabolism and Blood Flow in the Brain is given. This is followed by a more detailed explanation of functional MRI and how such experiments are performed.
The clinicpathologic features and MRI manifestations of the thoracic lumbar tuberculosis  [PDF]
Ruo-Qin Cheng, Hong-Hua Jin, Hua-Min Wang, Jun Zhou
Health (Health) , 2012, DOI: 10.4236/health.2012.412182
Abstract: Objective: To explore the clinicpathologic features and MRI manifestations of the thoracic lumbar tuberculosis by underwenting MRI and pathological examinations. Methods: 34 cases of Thoracic lumbar tuberculosis were collected which underwent MRI examination and confirmed by pathology or treatment of anti-TB drugs, the clinical cure from June 2008 to June 2012 in our hospital. The first MRI was performed on all patients, to determine the MRI findings, and surgical treatment for pathological examination in order to determine the pathological features. Results: 34 patients with 81 vertebral involvement, in which two adjacent vertebral involvement is the common, accounting for 72.25%, vertebral showed uneven long T1, long T2 signal. Intervertebral disc abnormalities accounted for 90.17%, the performance showed long T1, long T2 signal changes in the intervertebral disc damage, often accompanied by disc space narrowing or disappear. Paraspinal abscess accounted for 90.67%, often more than vertebra, up and down across one or more vertebral bodies showed long T1, long T2 signal. The vertebrae were damaged kyphosis or (and) the posterior longitudinal ligament abscess caused by the dural sac and spinal column with pressure accounted for 74.72%. In enhanced scan, vertebrae, intervertebral discs showed heterogeneous enhancement, paraspinal abscess was curved or ring enhancement. The pathological diagnosis may be obvious to confirm the degree of swelling and lesions. Conclusion: By doing the MRI and pathologic examinations, it can determine the clinical and pathological features and MRI findings of spinal tuberculosis patients with Thoracic lumbar spinal tuberculosis, and lay a reliable foundation for the treatment of the subsequent treatment.
Ectopic (heterotopic) pancreas in the mesentery of the jejunum: Imaging findings  [PDF]
Nihal Uslu
Case Reports in Clinical Medicine (CRCM) , 2013, DOI: 10.4236/crcm.2013.24075
Abstract:

Ectopic pancreatic tissue in the mesentery of the jejunum is an entity that is seen very rarely. Most patients are asymptomatic and usually this is an incidental ?nding at autopsy or laparotomy. Most of the cases are clinically silent, but symptoms either might be due to the localization of the ectopic tissue or due to the complications including obstruction or bleeding. Surgery is not indicated unless complications occur, so diagnosis is very important for prevention of unnecessary surgery. Here, we present a case that had ectopic pancreatic tissue in the mesentery of the jejunum. We show the computed tomography and magnetic resonance imaging findings of this patient.

Reliability and sensitivity to change of IW-TSE versus DESS magnetic resonance imaging sequences in the assessment of bone marrow lesions in knee osteoarthritis patients: Longitudinal data from the Osteoarthritis Initiative (OAI) cohort  [PDF]
Jean-Pierre Raynauld, Lukas Martin Wildi, Fran?ois Abram, Thomas Moser, Jean-Pierre Pelletier, Johanne Martel-Pelletier
Journal of Biomedical Science and Engineering (JBiSE) , 2013, DOI: 10.4236/jbise.2013.63A043
Abstract:

Background: Bone marrow lesions (BMLs) are associated with osteoarthritis (OA). We assessed the performance of two commonly used MRI sequences, IW-TSE and DESS, for reliability in the detection of BMLs and sensitivity to estimate change over time. We suggested that the IW-TSE would demonstrate higher sensitivity to change than DESS in the assessment of BML prevalence and change over time. This study was performed using a subset of the Osteoarthritis Initiative (OAI) cohort. Methods: A sub-group of 144 patients was selected from the OAI progression cohort who all had IW-TSE and DESS MRI acquisitions at baseline and 24 months. BMLs were assessed using a semi-quantitative scale in the global knee, medial and lateral compartments, and subregions. Intra-reader reliability was assessed on a subset of 51 patients. Results: Intra-reader reliability was substantial for the global knee ≥ 0.64, medial ≥ 0.70, and lateral ≥ 0.63 compartments for IW-TSE and DESS. The prevalence of BML detected at baseline was only slightly greater for IW-TSE compared to DESS. The mean BML score at baseline was significantly higher (p ≤ 0.006) for the IW-TSE than the DESS. However, mean change at 24 months was similar for both sequences for all regions except the medial compartment (p = 0.034) and medial femur (p = 0.015) where they were significantly higher for DESS than IW-TSE. Moreover, the prevalence of BML change at 24 months was similar in all regions except the global knee (p = 0.047) and the lateral tibial plateau (p = 0.031). Conclusion: This study does not suggest superior sensitivity to change of one sequence over the other for almost all the regions. The only difference is a higher BML mean change over time detected by the DESS sequence in the medial compartment and femur. These data bring into perspective that both sequences seem equivalent regarding their use for the assessment of BML in clinical trials.

Cystic Hygroma of the Neck: Ultrasound Findings  [PDF]
Marco Di Serafino, Carmela Mercogliano, Rosa Severino, Francesco Lisanti, Francesco Esposito, Rosario Rocca, Rosaria Abate, Tonino Cavallo
Open Journal of Radiology (OJRad) , 2016, DOI: 10.4236/ojrad.2016.62018
Abstract: This is a report of a case of cystic hygroma of the neck in a female child. Cystic hygroma is a rare congenital malformation of the lymphatic system, most frequently detected in the head and neck region. Ultrasound is considered as being the first level study to investigate a suspected mass suggestive of cystic hygroma. The Authors describe the main diagnostic ultrasound features for this type of lymphatic lesion.
Efficacy of Magnetic Resonance Imaging in BIRADS 3, 4 and 5 Patients Detected on Full Field Digital Mammography: Our Experience  [PDF]
Atul Patil, Samadhan Pawar, Raj Nagarkar, Bhargav Gaikwad
Open Journal of Clinical Diagnostics (OJCD) , 2019, DOI: 10.4236/ojcd.2019.91003
Abstract:

Aim of the study: To perform Dynamic contrast enhanced MRI of breast in patients with positive findings (BIRADS 3, 4 and 5) detected on screening mammography; to correlate the findings of digital mammography and contrast enhanced MRI of breast with histopathological examinations. Settings and Design: A prospective observation study was conducted at a single centre, i.e. HCG Manavata Cancer Centre. Materials and Methods: Screening mammography was performed on patients with age > 40 years and on patients with age 35 - 40 years having positive family history. The positive mammography was reported and the lesions classified according to BIRADS criteria for mammography. Results: Mammographic examination of the breast lesions yielded an overall sensitivity of 97.67% and a specificity of 85.71%. In our study we combined both morphologic and dynamic parameters and its modification into BIRADS category for lesion classification. The sensitivity of MRI examinations was 97.67% while the specificity was 71.43%. Spiculated margins were encountered only in malignant lesions (p = 0.0006). Statistical correlation was obtained between the pathologically proven benign and malignant lesions regarding their enhancement pattern with p value of <0.001. Conclusion: As per the results, dynamic contrast MRI had high sensitivity but limited specificity. We did not find any significant difference between FFDM and MRI in terms of diagnostic accuracy. The use of DWI showed high specificity at cut off point of ADC value0.85 mm2/s. Thus, DWI can

MRI of the Bladder in Patients Suspected of Bladder Tumors  [PDF]
Karen Lind Gandrup, J?rgen Nordling, Henrik S. Thomsen
Open Journal of Radiology (OJRad) , 2014, DOI: 10.4236/ojrad.2014.42028
Abstract: Objective: To prospectively evaluate the use of MRI for the detecting of bladder tumors and the T- stage using T2W, T1W and diffusion-weighted images (DWI). Material and methods: Twenty-eight consecutive patients (21 men, 7 women; age range, 20 - 82 years; mean age, 62.8 years) suspected of bladder tumors underwent MRI, flexible cystoscopy and transurethral resection (TURB). The presence of bladder tumor was confirmed by histopathology in 21 patients; 18 patients had pTa, one pT1 and two pT2. The images were reviewed by two uroradiologists. They assigned the presence of a bladder tumor and whether the tumor was non-muscle invasive (Ta and T1) or muscle- invasive (T2, T3 or T4). Results: Compared to the histopathological results, the accuracy for identifying a bladder tumor was 60.7% and 53.7% for reviewer A and B, respectively. The sensitivity and specificity were 66.7%/61.9% and 57.1%/42.9%. Positive predictive values were 82.6%/ 76.5%. The overall staging was correct in 47.6%/52.5%, but improved on stage-by-stage up to 50%/66.7%. The agreement between the reviewers was moderate in the detecting, staging and location of the tumor (Kappa = 0.47 - 0.57). Conclusion: A simple MRI using no contrast media, but DWI, cannot replace flexible cystoscopy in the detection of new or recurrent bladder tumors.


Brain MRI Findings in Infantile Spasm: Outcome Correlations in a Patient Cohort  [PDF]
Alireza Khatami, Erick Sell, Mohamed Aggag, Elka Miller
Open Journal of Medical Imaging (OJMI) , 2016, DOI: 10.4236/ojmi.2016.63008
Abstract: Background: Infantile spasm is a type of pediatric seizure often associated with a negative prognosis. The aim of this study was to evaluate the role of Magnetic Resonance Imaging (MRI) in categorization and neurodevelopmental outcomes in children with infantile spasm. Materials and Methods: A retrospective study of the clinical charts and MRI findings of infants diagnosed with infantile spasm between December 2007 and February 2014. Results: A total of 26 children (16 males; 1.6/1) were included: 8 of unknown etiology and 18 with a genetic/structural-metabolic causes. Unknown etiology cases revealed normal brain MRI in 5/8 (62.5%). In the genetic/ structural-metabolic group, only 2/18 (11.1%) had normal imaging. Abnormal imaging findings significantly correlated with genetic/structural-metabolic infantile spasm which had unfavorable neurodevelopmental outcome. Conclusion: Neuroimaging conveys substantial information to the further categorization of children with infantile spasm, providing not only relevant information of the underlying cause but also the prediction of the neurodevelopmental outcome.
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