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MRI Examination (mri + examination)
Selected AbstractsHigh-resolution MRI Enhances Identification of Lesions Amenable to Surgical Therapy in Children with Intractable EpilepsyEPILEPSIA, Issue 8 2004Monisha Goyal Summary:,Purpose: Many children with refractory epilepsy can achieve better seizure control with surgical therapy. An abnormality on magnetic resonance imaging (MRI), along with corroborating localization by other modalities, markedly increases chances of successful surgical outcome. We studied the impact of high-resolution MRI on the surgical outcome of intractable epilepsy. Methods: High-resolution MRI using four-coil phased surface array was obtained as part of the comprehensive presurgical protocol for children with focal onset intractable seizures evaluated by our epilepsy center during the first half of 2002. Results: Thirteen consecutive children, ages 5 to 18 years, entered this prospective study. For four patients with a lesion on a recent MRI examination with a standard head coil, management did not change with high-resolution MRI. Standard MRI in the other nine patients did not identify a lesion. However, high-resolution MRI with the phased-array surface coil found previously undiagnosed focal abnormalities in five of nine patients. These abnormalities included hippocampal dysplasia, hippocampal atrophy, and dual pathology with frontal cortical dysplasia. In four of nine patients, no identifiable lesion was identified on the high-resolution MRI. All patients underwent invasive monitoring. In three of five patients, newly diagnosed lesions correlated with EEG abnormalities, and resection was performed. Conclusions: In our center, high-resolution MRI identified lesions not detected by standard MRI in more than half the children (56%). Technical advances such as four-coil phased surface array MRI can help identify and better delineate lesions, improving the diagnosis of patients who are candidates for surgical treatment of refractory epilepsy. [source] LPL polymorphism predicts stroke risk in menGENETIC EPIDEMIOLOGY, Issue 3 2002Alanna C. Morrison Abstract Variation in lipid levels has been associated with atherosclerotic vascular disease, including stroke. Genes contributing to interindividual variation in lipid levels may play a role in the etiology of stroke, either through their effects on lipid synthesis and metabolism or through separate pathways. For this reason, we sought to examine the association between polymorphisms in the lipoprotein lipase (LPL) and apolipoprotein E (APOE) genes and subclinical and clinical stroke in the Atherosclerosis Risk in Communities (ARIC) Study. Subclinical stroke was determined by cerebral magnetic resonance imaging (MRI). Subclinical cerebral infarct cases (n = 197) were compared to a stratified random sample identified from individuals participating in the MRI examination (n = 200). Incidence of clinical ischemic stroke was determined by following the ARIC cohort for an average of 7.5 years for potential cerebrovascular events; 218 validated clinical ischemic strokes were identified. A stratified random sample of the ARIC cohort (CRS, n = 964) was used as the comparison group for clinical cases. The LPL S291-carrying genotypes and APOE ,2- and ,4-carrying genotypes were not significantly associated with subclinical or clinical stroke. The LPL X447-containing genotypes were significantly associated with subclinical (odds ratio [OR], 4.32; 95% confidence interval [CI], 1.23,15.15; P = 0.020) and clinical stroke (hazard rate ratio [HRR], 2.57; 95% CI, 1.24,5.34; P = 0.01) in men, both by themselves and after adjustment for multiple stroke risk factors. The LPL S447X polymorphism is significantly associated with subclinical cerebral infarction and incident clinical ischemic stroke in men from a middle-aged American population. This association does not appear to be mediated by triglyceride, high-density lipoprotein (HDL)- and low-density lipoprotein (LDL)-cholesterol levels, or additional stroke risk factors. Genet. Epidemiol. 22:233,242, 2002. © 2002 Wiley-Liss, Inc. [source] Time-resolved contrast-enhanced MR angiography of intracranial lesionsJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2008Zhitong Zou MD Abstract Purpose To determine if contrast-enhanced (CE) MRI of intracranial lesions benefits from time-resolved MR angiography (MRA) during contrast agent injection. Materials and Methods For 126 patients with suspected intracranial lesions undergoing routine CE MRI at 3.0T (N = 88) or 1.5T (N = 38), time-resolved CE MRA (three-dimensional [3D] time-resolved imaging of contrast kinetics [TRICKS]) was performed during injection of the routine gadolinium (Gd) dose of 0.1 mmol/kg. Time to peak (TTP) enhancement of lesions as well as time to internal carotid artery (ICA), middle cerebral artery (MCA), superior sagittal sinus (SSS), and jugular vein enhancement were measured. Source and maximum intensity projection (MIP) images were reviewed to delineate the spatial relationship of lesions and the vasculature. Results In 61 patients (48%), additional important findings were detected on time-resolved MRA that were not seen on the routine CE protocol, including aneurysms (N = 6), arteriovenous malformations (N = 7), ICA stenoses (N = 2), vascular anomalies (N = 18), and relationships between lesions and vessels (N = 28). In addition, tumor TTP correlated with glioma grade (r = 0.87) and discriminated epithelial from nonepithelial meningiomas (P = 2.6 × 10,5). MRA added eight minutes to the total exam time. Conclusion Time-resolved MRA performed during contrast agent injection adds information to the routine brain CE MRI examination of intracranial lesions with only a small time penalty and no additional risk to the patient. J. Magn. Reson. Imaging 2008. © 2008 Wiley-Liss, Inc. [source] Intracranial Vasculitis and Multiple Abscesses in a Pregnant WomanJOURNAL OF NEUROIMAGING, Issue 3 2001Mutlu Cihangiroglu ABSTRACT Cerebral vasculitis is an unusual disorder with many causes. Infectious causes of cerebral vasculitis are predominantly bacterial or viral in nature. Purulent bacterial vasculitis is most often a complication of severe bacterial meningitis. The patient is a 25-year-old African American female, 25 weeks pregnant, who presented to the neurology service after a consult and referral from an outside hospital. She had a 1-month history of right sixth nerve palsy. Initial workup included a negative lumber puncture and a noninfused magnetic resonance imaging (MRI). Three days later, the patient developed right-sided migraine headaches and right third nerve palsy. The angiogram revealed diffuse irregularity and narrowing of the petrous, cavernous, and supraclinoid portions of the internal carotid and right middle cerebral arteries. Shortly thereafter, an MRI examination revealed diffuse leptomeningeal enhancement and abscess and a right parietal subdural empyema. Infectious vasculitis secondary to purulent meningitis has a rapidly progressive course and presents with cranial nerve palsy with involvement of the cavernous sinus. Although the association of this disease with pregnancy has not been established, it should be recognized that the early imaging studies may be negative or discordant and follow-up imaging might be necessary. [source] Case of localized scleroderma associated with osteomyelitisTHE JOURNAL OF DERMATOLOGY, Issue 1 2010Eiji MUROI Abstract We report a 4-year-old girl presenting with progressive linear scleroderma affecting the right leg. Biopsy specimen disclosed typical histopathological findings of localized scleroderma. Right leg magnetic resonance imaging (MRI) showed high signal areas on T2 -weighted images on the subcutaneous fatty tissue, muscles and bone marrow, suggesting that skin inflammation extended to the bone marrow. Oral corticosteroid therapy was instituted with improvement of both skin sclerosis and MRI findings. Our observations suggest that MRI examination should be considered in patients with localized scleroderma to evaluate the extension of the inflammation. [source] Muscle magnetic resonance imaging shows distinct diagnostic patterns in Welander and tibial muscular dystrophyACTA NEUROLOGICA SCANDINAVICA, Issue 2 2004I. Mahjneh Objectives , This is a report on a retrospective muscle magnetic resonance imaging (MRI) study on 11 patients affected by Welander distal myopathy (WDM) and 22 patients with tibial muscular dystrophy (TMD) carried out in order to define the pattern and characteristics of muscle involvement. Results , WDM patients showed involvement of gastrocnemius, soleus, tibial anterior (TA) and extensor digitorum longus (EDL), as well as hamstrings and hip adductor muscles. TMD patients showed involvement of the TA and EDL muscles, and in some patients also hamstring and posterior compartment muscles of the legs. Some patients showed asymmetry of muscle involvement. Conclusion , We conclude that muscle MRI examination proved to be very useful in the determination of the exact pattern of muscle involvement in WDM and TMD. Clinical testing using the Medical Research Council scale is not sensitive enough to establish the pattern of muscle involvement in focal muscle diseases. [source] Cerebral MRI findings in a cohort of ex-preterm and control adolescentsACTA PAEDIATRICA, Issue 6 2009Zoltan Nagy Abstract Aim: Newborn infants were entered between 1988 and 1993 into a prospective, long-term, follow-up study. We aimed to investigate how the outcome of preterm-born individuals on cerebral magnetic resonance imaging (MRI) compared to that reported on similar cohorts internationally. Methods: The 74 ex-preterm (12.38,17.7 years, 51% girls) and 69 control participants (12.18,16.47 years, 53% girls) underwent a MRI examination on a 1.5T scanner. Two experienced neuroradiologists examined the T1- and T2-weigthed images first independently and then in consensus without knowledge of group adherence. Results: Only 21 (4 controls) of the 143 sets of scans showed any abnormalities. All but one of these were of mild extent. Among the ex-preterm adolescents two showed only incidental findings while the other 15 had either gliosis or white matter loss. Eleven subjects had white matter loss, seven of which had no other abnormalities. Four subjects had gliosis, three of which had no other abnormalities. The extent, severity or frequency of injury was not related to being born small for gestational age. Conclusion: Although the rate of structural abnormalities was higher in the group of adolescents born preterm, this rate was well below that reported from other centres around the world. We attribute this to the minimally invasive neonatal care and to different social structures in Sweden compared to that of other reports on similar cohorts. [source] Patterns of intraneural ganglion cyst descentCLINICAL ANATOMY, Issue 3 2008Robert J. Spinner Abstract On the basis of the principles of the unifying articular theory, predictable patterns of proximal ascent have been described for fibular (peroneal) and tibial intraneural ganglion cysts in the knee region. The mechanism underlying distal descent into the terminal braches of the fibular and tibial nerves has not been previously elucidated. The purpose of this study was to demonstrate if and when cyst descent distal to the articular branch-joint connection occurs in intraneural ganglion cysts to understand directionality of intraneural cyst propagation. In Part I, the clinical records and MRIs of 20 consecutive patients treated at our institution for intraneural ganglion cysts (18 fibular and two tibial) arising from the superior tibiofibular joint were retrospectively analyzed. These patients underwent cyst decompression and disconnection of the articular branch. Five of these patients developed symptomatic cyst recurrence after cyst decompression without articular branch disconnection which was done elsewhere prior to our intervention. In Part II, five additional patients with intraneural ganglion cysts (three fibular and two tibial) treated at other institutions without disconnection of the articular branch were compared. These patients in Parts I and II demonstrated ascent of intraneural cyst to differing degrees (12 had evidence of sciatic nerve cross-over). In addition, all of these patients demonstrated previously unrecognized MRI evidence of intraneural cyst extending distally below the level of the articular branch to the joint of origin: cyst within the proximal most portions of the deep fibular and superficial fibular branches in fibular intraneural ganglion cysts and descending tibial branches in tibial intraneural ganglion cysts. The patients in Part I had complete resolution of their cysts at follow-up MRI examination 1 year postoperatively. The patients in Part II had intraneural recurrences postoperatively within the articular branch, the parent nerve, and the terminal branches, although in three cases they were subclinical. The authors demonstrate that cyst descent distal to the take-off of the articular branch to the joint of origin occurs regularly in patients with fibular and tibial intraneural ganglion cysts. The authors believe that parent terminal branch descent follows ascent up the articular branch from an affected joint of origin. This mechanism for bidirectional flow explains cyst within terminal branches of the fibular and tibial nerves and is dependent on pressure fluxes and resistances. This new pattern is consistent with principles previously described in a unified (articular) theory, is generalizable to other intraneural ganglion cysts arising from joints, and has important implications for pathogenesis and treatment of these intraneural cysts. Clin. Anat. 21:233,245, 2008. © 2008 Wiley-Liss, Inc. [source] Effect of the preliminary hydration on gastric emptying time for water in healthy volunteersACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2009T. UMENAI Background: International guidelines allow healthy patients to drink clear liquid up to 2 h before general anesthesia. Recently, MRI measurements have been used for tracking gastric volume in humans. Hence, we used MRI to examine the gastric emptying rate of water in healthy volunteers with or without prior water loading. Methods: Fifteen healthy volunteers were enrolled. The participants had MRI examinations on separate days under two different protocols: The preliminary hydration protocol (group H) and the water restriction protocol (group R). After the intake of water, MR imaging was performed every 10 min for 60 min. The gastric content was outlined as area of interest (AOI), and the AOI area of each slice was summated to calculate the volume of gastric contents. Results: The 50% reduction time of gastric volume in group R and group H was 18±9 and 16±8 min (mean±SD), respectively. There were no significant changes between the two groups. Conclusion: The gastric emptying time for water evaluated with MRI was not affected by preliminary hydration, which shows the safety of repeated oral hydrations in the pre-operative period. [source] Intraparenchymal myofibromatosis of the brain in an adult: report of an unusual caseNEUROPATHOLOGY, Issue 3 2010Hua-liang Xiao An unusual case of intraparenchymal myofibromatosis of the brain occurring in a 29-year-old woman is described. Preoperative CT and MRI examinations revealed two well-circumscribed nodular masses localized in the wall of the left lateral ventricle and right temporal lobe, respectively. Both masses were completely resected, and the patient remains disease-free 2 years post-surgery. Histopathologically, the lesions were characterized by stratification. From outer to inner, there was a reactive glial component, lamellated well-differentiated muscle-like cells, densely compact collagen fibers and cellular tumor with nodular and hemangiopericytoma-like patterns, respectively. The myofibroblastic nature of this tumor was verified by immunohistochemical staining and ultrastructural analysis. Intraparenchymal myofibromatosis may be confused with, and should be distinguished from, meningioma, myopericytoma, solitary fibrous tumor, leiomyoma and inflammatory myofibroblastic tumor for accurate diagnosis and optimal treatment. [source] Non-invasive tracking of avian development in vivo by MRINMR IN BIOMEDICINE, Issue 4 2009Bianca Hogers Abstract Conventional microscopic techniques, to study embryonic development, require large numbers of embryos and are invasive, making follow-up impossible. We explored the use of in vivo MRI to study embryonic development, in general, and cardiovascular development in particular, over time. Wild-type quail embryos (n,=,11) were imaged at embryonic days 3, 5, 7, 9, and 11, covering the main time course of embryonic heart development. On each imaging day cardiac morphology was evaluated and embryonic length was measured. MRI-embryos as well as control embryos (n,=,11) were sacrificed at day 11 and scored for external malformations, while embryonic wet weight and stage were determined. In addition, venous clipped embryos (n,=,4), known to develop cardiovascular malformations, were scanned at regular intervals and sacrificed at day 9 for histological analysis ex vivo. We were able to follow heart development of individual quail embryos inside their shell non-invasively over time, with sufficient detail to study cardiac morphology in vivo. We did not find any adverse effect of the repeated MRI examinations on morphology, length, or weight. Prenatally diagnosed malformations, like ventricular septal defects and aortic arch interruptions were confirmed by histology. In conclusion, micro-MRI can be used to evaluate in vivo early embryonic development and to diagnose cardiovascular malformations prenatally. Copyright © 2008 John Wiley & Sons, Ltd. [source] | |||||||||||||