Magnetic Resonance Imaging Changes In Patients Research Articles

MRI of wrist and diffusion tensor imaging of the median nerve in patients with carpal tunnel syndrome.

Diagnosis of carpal tunnel syndrome (CTS) is based on the clinical symptoms and nerve conduction study. Magnetic resonance imaging (MRI) is non-invasive objective tool for assessing the median nerve and carpal tunnel. The purpose of this study was to evaluate MRI changes in patients with CTS, and compare them with healthy subjects. Forty-three CTS patients and 43 age matched control were included and scanned in a 3T MRI scanner. Cross-sectional areas (CSA) of median nerve were measured at the level of distal radio-ulnar joint level (CSA1), proximal row of carpal bone (CSA2), and hook of hamate (CSA3). Flattening ratio (FR) of median nerve, thickness of flexor retinaculum, median nerve signal intensity, and thenar muscles were assessed. Fractional anisotropy (FA), average diffusion coefficient (ADC), and radial diffusivity (RD) of median nerve of CTS patients were obtained from diffusion tensor imaging (DTI) and compared with those of controls. Thirty-three patients (76.7%) were female. Mean duration of the pain was 7.4 ± 2.6 months. The mean CSA1 (13.2 ± 4.2 mm2), CSA2 (12.5 ± 3.5 mm2), and CSA3 (9.2 ± 1.5 mm2) in CTS patients were significantly higher compared to control group: CSA1 (10.15 ± 1.64 mm2), CSA2 (9.38 ± 1.37 mm2), and CSA3 (8.4 ± 0.9 mm2), (P = 0.001 in all). The mean FR of median nerve and thickness of flexor retinaculum were increased in CTS patients. The mean FA was reduced in CTS patients compared to control proximal to carpal tunnel and within the tunnel. Mean ADC and RD values were higher in CTS patients as compared to control for both levels. MRI can detect subtle changes in the median nerve and thenar muscles in CTS and may be useful in equivocal cases and to exclude secondary causes of CTS. DTI shows reduced FA and increased ADC and RD in CTS patients.

Pattern of Lumbar MRI Changes in Patients with Chronic Low Back Pain in a Tertiary Care Center

Introduction: Chronic low back pain (LBP) is a common cause of disability worldwide. Magnetic resonance imaging (MRI) is an excellent non-invasive imaging modality for morphologic evaluation of the lumbar spine in patients with chronic low back pain because of its high contrast resolution and lack of ionizing radiation. This study was done to see the patterns of MRI changes in patients with chronic low back pain in a tertiary care center in Western Nepal. Methods: This was a cross-sectional study conducted on patients presenting with chronic low back pain. Eleven MRI parameters were noted and analyzed. Chi square test and Fisher’s Exact test were employed to see the associations between the various MRI findings. Results: A total of 108 patients were evaluated during the study period. MRI changes were noted in over 95% of the cases. Degenerative changes were the most common cause of low back pain, disc bulge being the most common MRI finding. A significant association was found between radiculopathy and decreased lumbar lordosis and vertebral endplate changes. Conclusion: MRI is an invaluable tool in the evaluation of chronic LBP because of its high resolution and lack of ionizing radiation. Significant MRI findings are noted in most of the cases of chronic LBP, degenerative changes being the most common and ranging from congenital to malignant lesions.

Acute and chronic magnetic resonance imaging of human herpesvirus-6 associated encephalitis

Human herpesvirus-6 (HHV-6) has been associated with central nervous system encephalitis in immunocompetent children. To determine acute and chronic changes on magnetic resonance imaging (MRI) of a series of consecutive pediatric immunocompetent patients diagnosed with HHV-6 associated encephalitis. A retrospective review of acute and chronic MRI findings of immunocompetent children diagnosed with HHV-6 associated encephalitis from 2001-2008 was performed. Diagnosis was established by real time polymerase chain reaction using HHV-6 U77 helicase gene-specific primers on cerebrospinal fluid during the acute phase of illness, excluding other known causes of encephalitis. Seven patients (four girls, ages 9 months-7 years) were diagnosed with HHV-6 associated encephalitis from 2001-2008. MRI abnormalities were present in six of seven patients. Three had bithalamic signal abnormalities on T2 weighted sequences that mimicked metabolic or demyelinating disease. All patients with MRI abnormalities had diffuse signal changes in the brainstem (n =5 ) and/or cerebellum (n =4 ). One patient with diffuse abnormalities in cortical grey and white matter, hippocampus, and cerebellum showed complete resolution of MRI findings after 1 month. Five patients had extensive necrosis of the acutely affected regions on follow up MRI 3 to 16 months post diagnosis. HHV-6 associated encephalitis can occur in immunocompetent children with a myriad of acute and chronic necrotizing changes on MRI. MRI abnormalities were seen predominantly in the thalami, brainstem, and cerebellum; and may be reflective of anatomical viral tropism. HHV-6 should be considered in the differential diagnosis of unexplained MRI changes in patients with encephalitis.

AB0723 Evaluation of MRI Changes in Patients with Ankylosing Spondylitis and their Correlation with Clinical and Functional Impairment at Different Disease Duration

BackgroundAnkylosing spondylitis (AS) is a chronic inflammatory rheumatic disease. Magnetic resonance imaging (MRI) is currently used not only to facilitate early diagnosis of the AS, but also to monitor the...

Spondyloarthritis-related and degenerative MRI changes in the axial skeleton - an inter- and intra-observer agreement study

BackgroundThe Back Pain Cohort of Southern Denmark (BaPa Cohort) was initiated with the aim of evaluating the clinical relevance of magnetic resonance imaging (MRI) in the diagnosis of early spondyloarthritis (SpA). In order to facilitate the collection of MRI data for this study, an electronic evaluation form was developed including both SpA-related and degenerative axial changes. The objective of the current study was to assess the intra- and inter-observer agreement of the MRI changes assessed.MethodsThree radiologists evaluated 48 MRI scans of the whole spine and the sacroiliac joints from a subsample of the BaPa Cohort, consisting of patients with non-specific low back pain and patients with different stages of SpA features. The spine was evaluated for SpA-related and degenerative MRI changes and the SIJ for SpA-related changes. Inter- and intra-observer agreements were calculated with kappa statistics. In the interpretation of the kappa coefficient, the standards for strength of agreement reported by Landis and Koch were followed.ResultsA total of 48 patients, 40% men and mean age of 31 years (range 18 – 40 years), were evaluated once by all three readers and re-evaluated by two of the readers after 4-12 weeks. For MRI changes in the spine, substantial to almost perfect observer agreement was found for the location and the size of vertebral signal changes and for disc degeneration and disc contour. For the sacroiliac joints, substantial or almost perfect observer agreement was found for the grading of bone marrow oedema and fatty marrow deposition, the depth of bone marrow oedema and for subchondral sclerosis. Global assessment of the SpA diagnosis had substantial to almost perfect observer agreements.ConclusionThe acceptable agreement for key MRI changes in the spine and sacroiliac joints makes it possible to use these MRI changes in the BaPa Cohort study and other studies investigating MRI changes in patients with non-specific low back pain and suspected SpA.

A longitudinal MRI study in children with Rasmussen syndrome

The aim of this study was to identify the presence of any neuroimaging patterns of Rasmussen syndrome using magnetic resonance imaging (MRI). This was a prospective study evaluating brain MRIs in seven children with neuropathologically proven Rasmussen syndrome. All patients were unresponsive to conventional antiepileptics; five patients subsequently underwent functional hemispherectomy, and two patients underwent cortical resection. Three to eight (mean = 4.7) MRIs per patient were performed, and neuropathologic examination of the brain was available. Serial MRIs were obtained between 12 months before and 9 months after the onset of epilepsia partialis continua. The most common region of initial MRI signal change was the frontocentral region (six patients). Three patterns of neuroimaging abnormalities were observed as follows: (1) normal MRI followed by increased signal intensity with progressive cortical atrophy over time, (2) initial increased focal signal intensity followed by decrease in spatial extent and degree of signal intensity; (3) initially increased signal intensity without further changes on follow-up scans. This observation suggests three possible distinct patterns of MRI changes in patients with Rasmussen syndrome and that the differences in these neuroimaging patterns may reflect inherent differences in the pathogenesis of Rasmussen syndrome.