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Assessment of brain cognitive functions in patients with vitamin B12 deficiency using resting state functional MRI: A longitudinal study.
Gupta, L, Gupta, RK, Gupta, PK, Malhotra, HS, Saha, I, Garg, RK
Magnetic resonance imaging. 2016;(2):191-6
Abstract
INTRODUCTION The resting state functional MRI (rsfMRI) approach is useful to explore the brain's functional organization in health and disease conditions. In this study, using rsfMRI the alteration in brain due to vitamin B12 deficiency and reversibility of these alterations following therapy was studied. METHODS Thirteen patients with clinical and biochemical evidence of vitamin B12 deficiency were recruited in this study. Fifteen age and sex matched healthy controls were also included. Patients and controls were clinically evaluated using neuropsychological test (NPT). The analysis was carried out using regional homogeneity (ReHo) and low frequency oscillations (LFO) of BOLD signals in resting state. Six patients were also evaluated with rsfMRI and NPT after 6 weeks replacement therapy. RESULTS ReHo values in patients with vitamin B12 deficiency were significantly lower than controls in the entire cerebrum and the brain networks associated with cognition control, i.e., default mode, cingulo-opercular and fronto-parietal network. There was no significant difference using LFO and it did not show significant correlations with NPT scores. ReHo showed significant correlation with NPT scores. All the 6 patients showed increase in ReHo after replacement therapy. CONCLUSION We conclude that brain networks associated with cognition control are altered in patients with vitamin B12 deficiency, which partially recover following six weeks of replacement therapy. This is the first study to evaluate the rsfMRI in the light of clinical neuropsychological evaluation in patients. rsfMRI may be used as functional biomarker to assess therapeutic response in vitamin B12 deficiency patients.
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Small-intestinal length measurement on MR enterography: comparison with in vivo surgical measurement.
Sinha, R, Trivedi, D, Murphy, PD, Fallis, S
AJR. American journal of roentgenology. 2014;(3):W274-9
Abstract
OBJECTIVE The purpose of this study is to assess the feasibility and accuracy of small-bowel length measurement on MR enterography examinations compared with surgical in vivo measurements. SUBJECTS AND METHODS Thirty-one consecutive patients who were undergoing elective laparotomy for Crohn disease were included in the study. These patients underwent a prior MR enterography examination, and true fast imaging with steady-state precession MR enterography images from the examinations were used to measure small-intestinal length. The MR enterography measurement was compared with a surgical measurement to assess accuracy and correlation. RESULTS MR enterography measurements had a significant positive correlation with surgical measurements (r(2) = 0.98; p < 0.001) irrespective of bowel length. The average (± SD) percentage difference between MR enterography and surgical intestinal length measurement was 4.59% ± 0.44%. An average time of 36.5 ± 2.8 minutes was required for bowel length measurement on MR enterography. A significantly longer time was required for measurement of bowel length greater than 300 cm versus shorter bowel length. CONCLUSION Small-bowel length measurements on MR enterography are accurate compared with anatomic measurements. MR enterography can provide an effective noninvasive investigation in planning surgical and nutritional intervention in patients with compromised bowel length.
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Quantitative evaluation of liver function with T1 relaxation time index on Gd-EOB-DTPA-enhanced MRI: comparison with signal intensity-based indices.
Kamimura, K, Fukukura, Y, Yoneyama, T, Takumi, K, Tateyama, A, Umanodan, A, Shindo, T, Kumagae, Y, Ueno, S, Koriyama, C, et al
Journal of magnetic resonance imaging : JMRI. 2014;(4):884-9
Abstract
PURPOSE To evaluate whether the reduction rate of T1 relaxation time of the liver (T1 relaxation time index) before and 20 minutes after gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) injection has the potential to serve as an magnetic resonance imaging (MRI)-based liver function test in comparison with signal intensity-based indices. MATERIALS AND METHODS Ninety-nine patients with suspected liver lesions underwent Gd-EOB-DTPA-enhanced MRI. T1 maps using 3D T1-weighted gradient-echo volumetric interpolated examination with two different flip angles were also performed before and 20 minutes after Gd-EOB-DTPA administration. T1 relaxation time index was compared with four signal intensity-based indices in terms of the ability to discriminate Child-Pugh A (CPA) and Child-Pugh B (CPB) from normal liver function (NLF), and in terms of its correlation with indocyanine green (ICG) clearance. RESULTS Twenty-four patients were classified as NLF, 64 patients were classified as CPA, and 11 were classified as CPB group. The T1 relaxation time index was significantly lower for CPA (0.62 ± 0.08 vs. 0.68 ± 0.07, P = 0.021) and CPB (0.55 ± 0.15 vs. 0.68 ± 0.07, P < 0.001) than for NLF. All signal intensity-based indices showed significant differences only when comparing NLF and CPB. The correlation coefficient with ICG clearance was the highest for T1 relaxation time index (r = -0.605, P < 0.001). CONCLUSION The T1 relaxation time index has the potential to serve as an MRI-based liver function test, and is most strongly correlated with ICG clearance among the Gd-EOB-DTPA MRI-based indices investigated.
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Fluctuations in eGFR in relation to unenhanced and enhanced MRI and CT outpatients.
Azzouz, M, Rømsing, J, Thomsen, HS
European journal of radiology. 2014;(6):886-892
Abstract
OBJECTIVE To study fluctuations in estimated glomerular filtration rate (eGFR) in relation to contrast medium (CM) enhanced magnetic resonance imaging (MRI) and computed tomography (CT) compared to control groups in outpatients. MATERIALS AND METHODS eGFR was determined right before the imaging procedure and three days later at the department or at the patient's home. The iodine-based and gadolinium-based contrast media were the same as used for all other examinations at the department. RESULTS A total of 716 patients completed the study. There was a statistically significant, but not clinically relevant rise in eGFR after three days in all four groups. The average eGFR variation was 4.8 ml/min/1.73 m(2). There were large variations in eGFR between the two measurements in 45.8% of the patients as they had a change greater than ± 10 ml/min/1.73 m(2). Only three patients fulfilled the contrast-induced nephropathy (CIN) requirement when the definition s-creatinine ≥ 44 μmol/l (0.5mg/dl) was used. CONCLUSIONS eGFR in outpatients undergoing MRI or CT did vary independently of whether the patient received contrast or not. The findings probably reflect the natural variations in s-creatinine levels. This should be taken into consideration when CIN is studied.
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MR characterization of hepatic storage iron in transfusional iron overload.
Tang, H, Jensen, JH, Sammet, CL, Sheth, S, Swaminathan, SV, Hultman, K, Kim, D, Wu, EX, Brown, TR, Brittenham, GM
Journal of magnetic resonance imaging : JMRI. 2014;(2):307-16
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Abstract
PURPOSE To quantify the two principal forms of hepatic storage iron, diffuse, soluble iron (primarily ferritin), and aggregated, insoluble iron (primarily hemosiderin) using a new MRI method in patients with transfusional iron overload. MATERIALS AND METHODS Six healthy volunteers and 20 patients with transfusion-dependent thalassemia syndromes and iron overload were examined. Ferritin- and hemosiderin-like iron were determined based on the measurement of two distinct relaxation parameters: the "reduced" transverse relaxation rate, RR2 , and the "aggregation index," A, using three sets of Carr-Purcell-Meiboom-Gill (CPMG) datasets with different interecho spacings. Agarose phantoms, simulating the relaxation and susceptibility properties of tissue with different concentrations of dispersed (ferritin-like) and aggregated (hemosiderin-like) iron, were used for validation. RESULTS Both phantom and in vivo human data confirmed that transverse relaxation components associated with the dispersed and aggregated iron could be separated using the two-parameter (RR2 , A) method. The MRI-determined total hepatic storage iron was highly correlated (r = 0.95) with measurements derived from biopsy or biosusceptometry. As total hepatic storage iron increased, the proportion stored as aggregated iron became greater. CONCLUSION This method provides a new means for noninvasive MRI determination of the partition of hepatic storage iron between ferritin and hemosiderin in iron overload disorders.
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Comparison of intraoperative fluorescence and MRI image guided neuronavigation in malignant brain tumours, a prospective controlled study.
Eljamel, S, Petersen, M, Valentine, R, Buist, R, Goodman, C, Moseley, H, Eljamel, S
Photodiagnosis and photodynamic therapy. 2013;(4):356-61
Abstract
INTRODUCTION MBT carry poor prognosis and more than 80% of MBT recur locally within 2 cm of the resection margin because of inadequate surgical removal. A number of techniques have been implemented in recent years to improve surgical removal of MBT with variable success. We examined two methods commonly used to resect MBT to establish which one offered the best chances of gross total removal; MRI guided technology and ALA-induced fluorescence. PATIENTS AND METHODS Twenty consecutive patients diagnosed with MBT were included in this study. They were given 20mg ALA per kg body weight 3h before anaesthesia orally mixed in water. Surgery was planned using preoperative enhanced MPR age images. Surgery was executed using the Stealth Station image guidance system and ALA-induced fluorescence microsurgical techniques. During surgery the intensity of fluorescence was graded into red, pink or blue. The intensity of fluorescence was also measured using pulsed 405 nm laser and a compact spectrometer using a touch probe directly placed on the tissue. The extent of tumour invasion was assessed intraoperatively using standard white light, blue light and spectroscopic measurements. Postoperative enhanced MRI was used to assess the extent of resection and the volume of residual tumour was measured. RESULTS There were six newly diagnosed GBM, eight recurrent GBM, one oligodendroglioma (ODG) and five metastases (MET). On enhanced MRI, the mean diameter of new GBM, recurrent GBM, ODG and MET was 2.3 cm, 2.3 cm, 1.5 cm, and 2.3 cm respectively. Under the blue light, the mean diameter of new GBM, recurrent GBM, ODG and MET was 2.9 cm, 3 cm, 1.5 cm and 2.3 cm respectively. The results of quantitative measurements of fluorescence ratios revealed that red fluorescence corresponded to 5.9-11.6 (solid tumour on histology), and pink fluorescence measured 0.8-1.9 (infiltrating edge of tumour on histology). When we compared the maximum tumour diameter of GBM we found on average it was 10mm wider on spectroscopy compared to standard white light microscopy and 6mm wider than what the enhanced MRI demonstrated. CONCLUSIONS Fluorescence technology revealed that GBMs are wider than the enhanced MRI had demonstrated, while MET enhanced MRI was similar in size to fluorescence. Furthermore, solid tumour can be identified intraoperatively and can be measured using fluorescence and spectroscopy techniques and it can be removed safely. Infiltrating tumour can also be identified intraoperatively using this technology and can be removed in non-eloquent areas to maximise surgical resection.
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Clinical MRI for iron detection in Parkinson's disease.
Rossi, M, Ruottinen, H, Soimakallio, S, Elovaara, I, Dastidar, P
Clinical imaging. 2013;(4):631-6
Abstract
We studied nonheme iron in Parkinson's disease (PD) using clinically available MRI in 36 patients and 21 healthy volunteers. The subjects underwent thorough clinical investigation, including 3-T MRI. Quantitative R2* was able to reflect symptoms of PD. In addition, the clinically used susceptibility-weighted imaging differentiated between controls and patients, whereas T2-weighted imaging did not. Disease-related changes were present not only in substantia nigra but also in globus pallidus. Such changes are associated with neurodegeneration, reflecting the severity of motor impairment.
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Magnetization transfer imaging demonstrates a distributed pattern of microstructural changes of the cerebral cortex in amyotrophic lateral sclerosis.
Cosottini, M, Pesaresi, I, Piazza, S, Diciotti, S, Belmonte, G, Battaglini, M, Ginestroni, A, Siciliano, G, De Stefano, N, Mascalchi, M
AJNR. American journal of neuroradiology. 2011;(4):704-8
Abstract
BACKGROUND AND PURPOSE To date, damage of the cerebral cortex neurons in ALS was investigated by using conventional MR imaging and proton MR spectroscopy. We explored the capability of MTI to map the microstructural changes in cerebral motor and extramotor cortices of patients with ALS. MATERIALS AND METHODS Twenty patients with ALS and 17 age-matched healthy controls were enrolled. A high-resolution 3D SPGR sequence with and without MT saturation pulses was obtained on a 1.5T scanner to compute MTR values. Using the FMRIB Software Library tools, we automatically computed the MTR of the cerebral cortex GM in 48 regions of the entire cerebral cortex derived from the standard Harvard-Oxford cortical atlas. RESULTS The MTR values were significantly lower in patients with ALS than in healthy controls in the primary motor cortex (precentral gyrus), nonprimary motor areas (superior and middle frontal gyri and superior parietal lobe), and some extramotor areas (frontal pole, planum temporale, and planum polare). No correlation was found between regional MTR values and the severity of clinical deficits or disease duration. CONCLUSIONS MTI analysis can detect the distributed pattern of microstructural changes of the GM in the cerebral cortex of patients with ALS with involvement of both the motor and extramotor areas.
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Lymphotropic nanoparticle-enhanced magnetic resonance imaging (LNMRI) identifies occult lymph node metastases in prostate cancer patients prior to salvage radiation therapy.
Ross, RW, Zietman, AL, Xie, W, Coen, JJ, Dahl, DM, Shipley, WU, Kaufman, DS, Islam, T, Guimaraes, AR, Weissleder, R, et al
Clinical imaging. 2009;(4):301-5
Abstract
Twenty-six patients with prostate cancer status post-radical prostatectomy who were candidates for salvage radiation therapy (SRT) underwent lymphotropic nanoparticle enhanced MRI (LNMRI) using superparamagnetic nanoparticle ferumoxtran-10. LNMRI was well tolerated, with only two adverse events, both Grade 2. Six (23%) of the 26 patients, previously believed to be node negative, tested lymph node positive by LNMRI. A total of nine positive lymph nodes were identified in these six patients, none of which were enlarged based on size criteria.
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MR spectroscopy (MRS) and magnetisation transfer imaging (MTI), lesion load and clinical scores in early relapsing remitting multiple sclerosis: a combined cross-sectional and longitudinal study.
Bellmann-Strobl, J, Stiepani, H, Wuerfel, J, Bohner, G, Paul, F, Warmuth, C, Aktas, O, Wandinger, KP, Zipp, F, Klingebiel, R
European radiology. 2009;(8):2066-74
Abstract
The purpose of this study was to correlate magnetic resonance imaging (MRI)-based lesion load assessment with clinical disability in early relapsing remitting multiple sclerosis (RRMS). Seventeen untreated patients (ten women, seven men; mean age 33.0 +/- 7.9 years) with the initial diagnosis of RRMS were included for cross-sectional as well as longitudinal (24 months) clinical and MRI-based assessment in comparison with age-matched healthy controls. Conventional MR sequences, MR spectroscopy (MRS) and magnetisation transfer imaging (MTI) were performed at 1.5 T. Lesion number and volume, MRS and MTI measurements for lesions and normal appearing white matter (NAWM) were correlated to clinical scores [Expanded Disability Status Scale (EDSS), Multiple Sclerosis Functional Composite (MSFC)] for monitoring disease course after treatment initiation (interferon beta-1a). MTI and MRS detected changes [magnetisation transfer ratio (MTR), N-acetylaspartate (NAA)/creatine ratio] in NAWM over time. EDSS and lesional MTR increases correlated throughout the disease course. Average MTR of NAWM raised during the study (p < 0.05) and correlated to the MSFC score (r = 0.476, p < 0.001). At study termination, NAA/creatine ratio of NAWM correlated to the MSFC score (p < 0.05). MTI and MRS were useful for initial disease assessment in NAWM. MTI and MRS correlated with clinical scores, indicating potential for monitoring the disease course and gaining new insights into treatment-related effects.