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MRI Evaluation (mri + evaluation)
Selected AbstractsDark lumen magnetic resonance enteroclysis in combination with mri colonography for whole bowel assessment in patients with Crohn's disease: First clinical experienceINFLAMMATORY BOWEL DISEASES, Issue 4 2005Andreas G Schreyer MD Abstract Background: Magnetic resonance enteroclysis (MRE) is a recently introduced imaging technique that assesses the small bowel with similar sensitivity and specificity as the fluoroscopically performed conventional enteroclysis. Magnetic resonance imaging colonography (MRC) seems to be a promising technique for polyp assessment in the colon. In this feasibility study, we evaluated the combination of small bowel MRI with unprepared MRC as an integrative diagnostic approach of the whole bowel in patients with Crohn's disease. Methods: Thirty patients with known Crohn's disease were prospectively examined. No particular colonic preparation was applied. Applying the dark lumen technique in all patients, MRE and MRC were performed within 1 session using an integrative examination protocol. T2-weighted and contrast-enhanced T1-weighted sequences were acquired. Inflammation assessment (grades 0 to 2) of the colon was compared with conventional colonoscopy in 29 patient and with surgery in 1 patient. The entire colon was graded fair to good distended in all patients. In 11 of 210 evaluated colonic segments, feces hindered an adequate intraluminal bowel assessment. Twenty-three of 30 patients had complete colonoscopy as the gold standard. In 7 patients, complete colonoscopy could not be performed because of an inflamed stenosis. Results: Correct grading of colonic inflammation was performed with 55.1% sensitivity and 98.2% specificity in all segments. Considering only more extensive inflammation (grade 2), the sensitivity of MRC increased to 70.2% with a specificity of 99.2%. Conclusions: The combination of MRE and MRC could improve the diagnostic value of abdominal MRI evaluation in patients with Crohn's disease. However, MRC can not replace conventional colonoscopy in subtle inflammation assessment. [source] Cardiac MRI evaluation of nonischemic cardiomyopathiesJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 3 2010Christopher J. François MD Abstract The purpose of this manuscript is to review the major MRI findings in patients with nonischemic cardiomyopathies. Cardiac MRI has become an integral part in the diagnosis and management of patients with nonischemic cardiomyopathies. Findings on cardiac MRI studies can help distinguish between different types of cardiomyopathies and can provide valuable diagnostic and prognostic information. J. Magn. Reson. Imaging 2010;31:518,530. © 2010 Wiley-Liss, Inc. [source] Central Pontine Signal Changes in Wilson's Disease: Distinct MRI Morphology and Sequential Changes with De-Coppering TherapyJOURNAL OF NEUROIMAGING, Issue 4 2007Sanjib Sinha DM ABSTRACT BACKGROUND AND PURPOSE Reports of central pontine myelinolysis (CPM)-like changes in Wilson's disease (WD) and its sequential changes are exceptional. The aim was to study the MRI characteristics of CPM-like changes in WD and the serial changes. METHODS Among the 121 patients of WD, twenty (M:F:9:11, age at onset: 14.2 ± 4.6 years) had features similar to CPM. All had progressive neuropsychiatric form of WD. All except five were on de-coppering treatment. None had acute deterioration or hepatic failure. Ten patients underwent repeat studies. RESULTS Twenty patients with CPM-like changes manifested with characteristic phenotype of WD. Three distinct patterns of CPM-like changes were observed: (a) characteristic round shape -7, (b) "bisected" -9, and (c) "trisected" -4. Only one had signal changes suggesting extra-pontine myelinolysis. All patients had contiguous involvement of midbrain. Serial MRI evaluation in 10 patients, at mean interval period of 17.4 ± 13.2 months, revealed complete reversal in one, partial improvement in five, and no change in three. Clinical and MRI improvement occurred pari passu, except in one. CONCLUSIONS CPM-like changes in WD are perhaps under-recognized and are distinct from the commonly known "osmotic demyelination." It is potentially reversible similar to other MRI features of WD. [source] Assessment of blood volume, vessel size, and the expression of angiogenic factors in two rat glioma models: a longitudinal in vivo and ex vivo studyNMR IN BIOMEDICINE, Issue 10 2008Samuel Valable Abstract Assessment of angiogenesis may help to determine tumor grade and therapy follow-up. In vivo imaging methods for non-invasively monitoring microvasculature evolution are therefore of major interest for tumor management. MRI evaluation of blood volume fraction (BVf) and vessel size index (VSI) was applied to assess the evolution of tumor microvasculature in two rat models of glioma (C6 and RG2). The results show that repeated MRI of BVf and VSI , which involves repeated injection of an iron-based MR contrast agent , does not affect either the physiological status of the animals or the accuracy of the MR estimates of the microvascular parameters. The MR measurements were found to correlate well with those obtained from histology. They indicate that microvascular evolution differs significantly between the two glioma models, in good agreement with expression of angiogenic factors (vascular endothelial growth factor, angiopoietin-2) and with activities of matrix metalloproteinases, also assessed in this study. These MRI methods thus provide considerable potential for assessing the response of gliomas to anti-angiogenic and anti-vascular agents, in preclinical studies as well as in the clinic. Furthermore, as differences between the fate of tumor microvasculature may underlie differences in therapeutic response, there is a need for preclinical study of several tumor models. Copyright © 2008 John Wiley & Sons, Ltd. [source] Gd(III)-EPTPAC16, a new self-assembling potential liver MRI contrast agent: in vitro characterization and in vivo animal imaging studies,NMR IN BIOMEDICINE, Issue 4 2008Suzana Torres Abstract The recently reported amphiphilic chelate, [Gd(EPTPAC16)(H2O)]2,, forms supramolecular aggregates in aqueous solution by self-assembly of the monomers with a relaxometrically determined critical micellar concentration (CMC) of 0.34,mM. The effect of sonication on the aggregate size was characterized by dynamic light scattering and relaxometry, indicating the presence of premicellar aggregates and an overall decrease in aggregate size and polydispersity upon sonication, slightly below the CMC. {[153Sm](EPTPAC16)(H2O)}2, radiotracer was evaluated in vivo from , scintigraphy and biodistribution in Wistar rats. It was found to depend strongly on the sample concentration, below or above the CMC, and its sonication, in a way that correlates with the effect of the same factors on the size of the aggregates formed in solution. Below CMC, the very large aggregates of the [153Sm]3+ -labeled chelate were persistently and mainly taken up by the lungs, and also by the macrophage-rich liver and spleen. Sonication of this solution led to loss of the lung uptake. Above CMC, the metal chelate was mainly taken up by the liver, with very little uptake by the spleen and lungs. In vivo, dynamic contrast-enhanced (DCE)-MRI evaluation of the micellar [Gd(EPTPAC16)(H2O)]2, compound in Wistar rats showed a persistent hepatic positive-contrast effect in T1 -weighted images, qualitatively similar to the clinically established GdIII -based hepatobiliary-selective agents. No enhancement effect was observed in the lungs because of the scarcity of mobile protons in this organ, despite the scintigraphic evidence of significant lung retention of the [153Sm]3+ -labeled chelate at concentrations below the CMC. Copyright © 2007 John Wiley & Sons, Ltd. [source] Smaller pituitary volume in adult patients with obsessive,compulsive disorderPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2009Murad Atmaca md Aims:, Another structure in the obsessive,compulsive disorder (OCD) circuit may be the pituitary gland because of the fact that limbic,hypothalamic,pituitary,adrenal (LHPA) axis abnormality has been reported in patients with OCD. There has been only one prior study, however, concerning pituitary volumetry, in which the sample was a pediatric group. The purpose of the present study was therefore to investigate this in an adult OCD patient group using magnetic resonance imaging (MRI). Methods:, Pituitary volume was measured in 23 OCD patients and the same number of healthy control subjects. Volumetric measurements were made on T1-weighted coronal MRI, with 2.40-mm-thick slices, at 1.5 T, and were done blindly. Results:, A statistically significantly smaller pituitary volume was found in OCD patients compared to healthy controls (age and intracranial volume as covariates). With regard to gender and diagnosis, there was a significant difference in pituitary gland volume (F = 4.18, P < 0.05). In addition, post-hoc analysis indicated near-significant difference in men with OCD as compared with women with OCD (P = 0.07) and significant difference between control men and control women (F = 10.96, P < 0.001). Conclusions:, Taking into consideration that the prior study found decreases in pituitary volume in pediatric patients with OCD as compared with healthy control subjects, future large MRI studies should investigate pituitary size longitudinally, with a careful characterization of hypothalamo-pituitary-adrenal (HPA) function in conjunction with anatomic MRI evaluation. [source] Response measurement after intraarterial chemoradiation in advanced head and neck carcinomaCANCER, Issue 8 2006Magnetic resonance imaging, evaluation under general anesthesia? Abstract BACKGROUND The objectives of this prospective trial were to evaluate the diagnostic accuracy and predictive value of magnetic resonance imaging (MRI) and to use MRI evaluation under general anesthesia (EGA) 6 to 8 weeks after chemoradiation to determine local control. METHODS Eighty-two consecutive patients with advanced-stage squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or supraglottic larynx were treated with selective targeted chemoradiation. All patients who completed treatment and survived had a minimum follow-up of 3 years. MRI and EGA were performed from 6 to 8 weeks after treatment. Posttreatment MRI findings were compared with pretreatment MRI findings and were graded for risk of local recurrence/residual disease on a 4-point scale. The diagnosis of treatment failure was based on tissue biopsies, which were obtained during EGA or later during follow-up. The predictive value of MRI was analyzed by using a Cox proportional hazards model. RESULTS Only 1 patient with MRI Grade 0 or 1 findings (discrete mass < 10 mm; n = 62 patients) had residual disease 6 to 8 weeks after treatment that was detected during EGA. In 5 patients with MRI findings of Grade 2a and 2b (mass > 10 mm; n = 20 patients), residual disease was detected. After 2 years, 23 patients had a local failure (28%). Twelve local failures were found among 62 patients who had MRI findings of Grade 0 and 1. Posttreatment MRI emerged as an independent predictive factor (hazard ratio, 3.0; P = .014) for local control. CONCLUSIONS Posttreatment MRI studies provided predictive information on local control in addition to pretreatment predictors. In patients with focal masses < 10 mm, the combination of response evaluation under general anesthesia and posttreatment MRI from 6 to 8 weeks after chemoradiation hardly provided more information on the local control than posttreatment MRI alone. Cancer 2006. © 2006 American Cancer Society. [source] Role of endoscopic surgery in the management of selected malignant epithelial neoplasms of the naso-ethmoidal complexHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 12 2007Piero Nicolai MD Abstract Background. This study reviews the outcome of patients with adenocarcinoma (AC) and squamous cell carcinoma (SCC) of the naso-ethmoidal complex treated by endoscopic surgery. Methods. Sixteen patients underwent a purely endoscopic excision of AC (n = 12) or SCC (n = 4) at 2 university hospitals. All patients were prospectively followed by endoscopic and MRI evaluations. Results. The tumor originated from the ethmoid in 13 cases and the nasal fossa in 3. Lesions were staged as follows: 5 T1, 10 T2, and 1 T3. Adjuvant radiotherapy was delivered in 7 cases. Follow-up (range, 28,70 months; mean, 47.25) was available for all patients. One patient died for brain metastases 28 months after surgery. Another patient required salvage craniofacial resection and radiotherapy for recurrent AC. Five-year disease-specific and disease-free survival rates were 93.3% and 87.0%, respectively. Conclusions. In selected T1-T2 lesions of the naso-ethmoidal complex, endoscopic surgery seems to offer a satisfactory alternative to external procedures. © 2007 Wiley Periodicals, Inc. Head Neck, 2007 [source] Incidence and Severity of Epidural Fibrosis after Back Surgery: An Endoscopic StudyPAIN PRACTICE, Issue 1 2010FIPP, Hemmo A. Bosscher MD Abstract Background: Epidural fibrosis has been implicated in the etiology of persistent pain after back surgery (Failed Back Surgery Syndrome [FBSS]). Using spinal endoscopy to view the lumbosacral epidural cavity, the incidence, severity, and appearance of epidural fibrosis was evaluated in patients with FBSS. Methods: A prospective cohort observational study using epidural endoscopy was done involving 78 patients with persistent pain after back surgery. Patients were evaluated prospectively for the presence of epidural fibrosis and fibrosis was rated using a 4-level grading system based on appearance and resistance to epiduroscope advancement. The incidence of fibrosis detected by epiduroscopy vs. the incidence as reported in magnetic resonance imaging (MRI) studies for the same patients were compared. Results: As diagnosed with epiduroscopy, 83.3% of all patients with persistent pain after back surgery had severe (grade 3 or 4) epidural fibrosis, while 91.0% had significant (grade 2, 3, or 4) fibrosis. In patients who had undergone more extensive surgery, severe fibrosis was present in 91.1% and significant fibrosis in 95.6%. Using MRI, epidural fibrosis was diagnosed only in 16.1% of these patients. All patients with severe epidural fibrosis had a filling defect on epidurography. Concordant pain was present in 84.3% of patients and depended on the severity of fibrosis. Results were statistically evaluated using analysis of frequencies and t -test. P < 0.05 was considered statistically significant. Conclusions: Epiduroscopy demonstrates that the prevalence of severe epidural fibrosis after FBSS is substantially higher than is generally reported in MRI evaluations. Severe epidural fibrosis is an underlying pathology in most patients with FBSS. [source] Surgical and radiotherapy treatment of a spinal cord ependymoma in a dogAUSTRALIAN VETERINARY JOURNAL, Issue 1-2 2006H. UENO A 4-year-old Beagle dog was presented for investigation of a left pelvic limb gait abnormality. Neurolocalisation indicated a lumbar (L2 to L5) spinal cord lesion. On magnetic resonance imaging (MRI), an intramedullary mass was demonstrated at L3. The mass was partially removed under general anaesthesia and a diagnosis of ependymoma was made on histological examination. The dog was treated with postoperative orthovoltage x-ray radiation (total dose; 44 Gy given in 11 fractions over a 4 week period) combined with low dose carbo-platin (25 mg/m2). The dog was alive 16 months after surgery without further neurological deficits. No further tumour growth was detected on subsequent MRI evaluations. [source] | ||||||||||