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Shams S, Martola J, Cavallin L, Granberg T, Shams M, Aspelin P, Wahlund LO, Kristoffersen-Wiberg M. SWI or T2*: which MRI sequence to use in the detection of cerebral microbleeds? The Karolinska Imaging Dementia Study. AJNR Am J Neuroradiol 2015; 36:1089-95. [PMID: 25698623 DOI: 10.3174/ajnr.a4248] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/16/2014] [Indexed: 12/31/2022]
Abstract
BACKGROUND AND PURPOSE Cerebral microbleeds are thought to have potentially important clinical implications in dementia and stroke. However, the use of both T2* and SWI MR imaging sequences for microbleed detection has complicated the cross-comparison of study results. We aimed to determine the impact of microbleed sequences on microbleed detection and associated clinical parameters. MATERIALS AND METHODS Patients from our memory clinic (n = 246; 53% female; mean age, 62) prospectively underwent 3T MR imaging, with conventional thick-section T2*, thick-section SWI, and conventional thin-section SWI. Microbleeds were assessed separately on thick-section SWI, thin-section SWI, and T2* by 3 raters, with varying neuroradiologic experience. Clinical and radiologic parameters from the dementia investigation were analyzed in association with the number of microbleeds in negative binomial regression analyses. RESULTS Prevalence and number of microbleeds were higher on thick-/thin-section SWI (20/21%) compared with T2*(17%). There was no difference in microbleed prevalence/number between thick- and thin-section SWI. Interrater agreement was excellent for all raters and sequences. Univariate comparisons of clinical parameters between patients with and without microbleeds yielded no difference across sequences. In the regression analysis, only minor differences in clinical associations with the number of microbleeds were noted across sequences. CONCLUSIONS Due to the increased detection of microbleeds, we recommend SWI as the sequence of choice in microbleed detection. Microbleeds and their association with clinical parameters are robust to the effects of varying MR imaging sequences, suggesting that comparison of results across studies is possible, despite differing microbleed sequences.
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Affiliation(s)
- S Shams
- From the Department of Clinical Science, Intervention, and Technology, Division of Medical Imaging and Technology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.) Department of Radiology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.)
| | - J Martola
- From the Department of Clinical Science, Intervention, and Technology, Division of Medical Imaging and Technology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.) Department of Radiology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.)
| | - L Cavallin
- From the Department of Clinical Science, Intervention, and Technology, Division of Medical Imaging and Technology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.) Department of Radiology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.)
| | - T Granberg
- From the Department of Clinical Science, Intervention, and Technology, Division of Medical Imaging and Technology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.) Department of Radiology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.)
| | - M Shams
- From the Department of Clinical Science, Intervention, and Technology, Division of Medical Imaging and Technology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.) Department of Radiology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.)
| | - P Aspelin
- From the Department of Clinical Science, Intervention, and Technology, Division of Medical Imaging and Technology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.) Department of Radiology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.)
| | - L O Wahlund
- Department of Neurobiology, Care Sciences, and Society (L.O.W.), Karolinska Institutet, Stockholm, Sweden Division of Clinical Geriatrics (L.O.W.), Karolinska University Hospital, Stockholm, Sweden
| | - M Kristoffersen-Wiberg
- From the Department of Clinical Science, Intervention, and Technology, Division of Medical Imaging and Technology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.) Department of Radiology (S.S., J.M., L.C., T.G., M.S., P.A., M.K.-W.)
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352
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Bittersohl B, Hosalkar HS, Miese FR, Schibensky J, König DP, Herten M, Antoch G, Krauspe R, Zilkens C. Zonal T2* and T1Gd assessment of knee joint cartilage in various histological grades of cartilage degeneration: an observational in vitro study. BMJ Open 2015; 5:e006895. [PMID: 25667150 PMCID: PMC4322206 DOI: 10.1136/bmjopen-2014-006895] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVES Accurate assessment of cartilage status is increasingly becoming important to clinicians for offering joint preservation surgeries versus joint replacements. The goal of this study was to evaluate the validity of three-dimensional (3D), gradient-echo (GRE)-based T2* and T1Gd mapping for the assessment of various histological severities of degeneration in knee joint cartilage with potential implications for clinical management. METHODS MRI and histological assessment were conducted in 36 ex vivo lateral femoral condyle specimens. The MRI protocol included a 3D GRE multiecho data image combination sequence in order to assess the T2* decay, a 3D double-echo steady-state sequence for assessment of cartilage morphology, and a dual flip angle 3D GRE sequence with volumetric interpolated breathhold examination for the T1Gd assessment. The histological sample analysis was performed according to the Mankin system. The data were then analysed statistically and correlated. RESULTS We observed a significant decrease in the T2* and T1Gd values with increasing grades of cartilage degeneration (p<0.001) and a moderate correlation between T2* (r=0.514)/T1Gd (r=0.556) and the histological grading of cartilage degeneration (p<0.001). In addition, we noted a zonal variation in the T2* and T1Gd values reflecting characteristic zonal differences in the biochemical composition of hyaline cartilage. CONCLUSIONS This study outlines the potential of GRE-based T2* and T1Gd mapping to identify various grades of cartilage damage. Early changes in specific zones may assist clinicians in identifying methods of early intervention involving the targeted joint preservation approach versus moving forward with unicompartmental, bicompartmental or tricompartmental joint replacement procedures. TRIAL REGISTRATION NUMBER DRKS00000729.
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Affiliation(s)
- Bernd Bittersohl
- Medical Faculty, Department of Orthopaedics, University Düsseldorf, Düsseldorf, Germany
| | - Harish S Hosalkar
- Center of Hip Preservation and Children's Orthopaedics, San Diego, California, USA
| | - Falk R Miese
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Düsseldorf, Düsseldorf, Germany
| | - Jonas Schibensky
- Medical Faculty, Department of Orthopaedics, University Düsseldorf, Düsseldorf, Germany
| | | | - Monika Herten
- Medical Faculty, Clinic for Vascular and Endovascular Surgery, University Münster, Münster, Germany
| | - Gerald Antoch
- Medical Faculty, Department of Diagnostic and Interventional Radiology, University Düsseldorf, Düsseldorf, Germany
| | - Rüdiger Krauspe
- Medical Faculty, Department of Orthopaedics, University Düsseldorf, Düsseldorf, Germany
| | - Christoph Zilkens
- Medical Faculty, Department of Orthopaedics, University Düsseldorf, Düsseldorf, Germany
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353
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Mashita T, Kamishina H, Nakamoto Y, Akagi Y, Nakanishi A, Harasaki Y, Ozawa T, Uemura T, Kobatake Y, Shimamura S, Kitamura N, Maeda S, Uzuka Y, Shaw G, Yasuda J. Combination of serum phosphorylated neurofilament heavy subunit and hyperintensity of intramedullary T2W on magnetic resonance imaging provides better prognostic value of canine thoracolumbar intervertebral disc herniation. J Vet Med Sci 2015; 77:433-8. [PMID: 25650056 PMCID: PMC4427744 DOI: 10.1292/jvms.14-0582] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to evaluate the prognostic value of concurrent measurement of serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent measurement of these would provide a more accurate prediction of functional outcome in dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2), deep pain perception and surgical outcome were evaluated with logistic regression analysis after three months for all 94 surgically treated dogs. Sensitivity to predict non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both. Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were significantly correlated with surgical outcome (P<0.05); however, deep pain perception was not (P=0.41). The results of logistic regression analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6 ng/ml, using T2H/L2 value of>0.84 and using both serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%, respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful for predicting long-term outcome in dogs with thoracolumbar IVDH.
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Affiliation(s)
- Tadahisa Mashita
- Maizuru Animal Medical Center, 8-22 Hamamachi, Kyoto; Department of Clinical Veterinary Science, United Graduate School of Veterinary Science, Gifu University, 1-1 Yanagito 509-1193, Japan.
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354
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Ha BC, Jung J, Kwak BK. Susceptibility-weighted imaging for stem cell visualization in a rat photothrombotic cerebral infarction model. Acta Radiol 2015; 56:219-27. [PMID: 24574360 DOI: 10.1177/0284185114525605] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND In cell therapy, magnetic resonance imaging (MRI) has been used to visualize superparamagnetic iron oxide (SPIO)-labeled stem cells homing to a lesion. Improving traceability is to utilize the sequence that maximizes sensitivity to the susceptibility effect of SPIO. PURPOSE To explore the best method by comparing the MRI sequences to visualize mesenchymal stem cells (MSCs) labeled with SPIO. MATERIAL AND METHODS Human bone marrow (hBM)-derived MSCs were labeled by internalization of SPIO nanoparticles. In vitro MRI was performed for the SPIO-labeled hBM-MSCs in tubes with T2-weighted (T2W), T2*-weighted (T2*W), and susceptibility-weighted images (SWI). Contrast-to-noise ratio (CNR) and volumes of dark signal of SPIO-labeled hBM-MSCs were obtained on images of each sequence. Photothrombotic cerebral infarction (PTCI) was induced in eight rats, and 2.5 × 10(5) SPIO-labeled hBM-MSCs were infused through the tail vein on the third day. In vivo MRI of the rat brain was performed using a 3.0 T MRI on the first, third, seventh, and 14th days. CNRspio was obtained on T2W imaging, T2*W imaging, and SWI. The dark signals were compared with the SPIO-positive cells of Prussian blue staining. RESULTS In vitro MRI of 5 × 10(5) SPIO-labeled hBM-MSCs showed the CNR and volume of dark signal to be 63, 517 mm(3) in SWI, 41, 228 mm(3) in T2*W imaging, and 56, 41 mm(3) in T2W imaging, respectively. In vivo MRI showed a dark signal surrounding the high signal intensity of PTCI. Pathologically, the dark signals were matched with SPIO-labeled hBM-MSC in the corresponding rat. The dark signal was most prominent in SWI, then T2*W imaging, and finally in T2W imaging (P <0.05). In SWI, other causes of dark signals were matched with the veins and the choroid plexuses on histopathology. CONCLUSION SWI can visualize SPIO-labeled hBM-MSCs more sensitively, earlier, and with larger size and greater contrast than T2W imaging and T2*W imaging.
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Affiliation(s)
- Bon Chul Ha
- Department of Radiology, Chung-Ang University Hospital, Seoul, Republic of Korea
| | - Jisung Jung
- Department of Radiology, Chung-Ang University Hospital, Seoul, Republic of Korea
| | - Byung Kook Kwak
- Department of Radiology, Chung-Ang University Hospital, Seoul, Republic of Korea
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355
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Rodjan F, de Graaf P, van der Valk P, Hadjistilianou T, Cerase A, Toti P, de Jong MC, Moll AC, Castelijns JA, Galluzzi P. Detection of calcifications in retinoblastoma using gradient-echo MR imaging sequences: comparative study between in vivo MR imaging and ex vivo high-resolution CT. AJNR Am J Neuroradiol 2015; 36:355-60. [PMID: 25523593 DOI: 10.3174/ajnr.a4163] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Intratumoral calcifications are very important in the diagnosis of retinoblastoma. Although CT is considered superior in detecting calcification, its ionizing radiation, especially in patients with hereditary retinoblastoma, should be avoided. The purpose of our study was to validate T2*WI for the detection of calcification in retinoblastoma with ex vivo CT as the criterion standard. MATERIALS AND METHODS Twenty-two consecutive patients with retinoblastoma (mean age, 21 months; range, 1-71 months) with enucleation as primary treatment were imaged at 1.5T by using a dedicated surface coil. Signal-intensity voids indicating calcification on T2*WI were compared with ex vivo high-resolution CT, and correlation was scored by 2 independent observers as poor, good, or excellent. Other parameters included the shape and location of the signal-intensity voids. In 5 tumors, susceptibility-weighted images were evaluated. RESULTS All calcifications visible on high-resolution CT could be matched with signal-intensity voids on T2*WI, and correlation was scored as excellent in 17 (77%) and good in 5 (23%) eyes. In total, 93% (25/27) of the signal-intensity voids inside the tumor correlated with calcifications compared with none (0/8) of the signal-intensity voids outside the tumor. Areas of nodular signal-intensity voids correlated with calcifications in 92% (24/26), and linear signal-intensity voids correlated with hemorrhage in 67% (6/9) of cases. The correlation of signal-intensity voids on SWI was better in 4 of 5 tumors compared with T2*WI. CONCLUSIONS Signal-intensity voids on in vivo T2*WI correlate well with calcifications on ex vivo high-resolution CT in retinoblastoma. Gradient-echo sequences may be helpful in the differential diagnosis of retinoblastoma. The combination of funduscopy, sonography, and high-resolution MR imaging with gradient-echo sequences should become the standard diagnostic approach for retinoblastoma.
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Affiliation(s)
- F Rodjan
- From the Departments of Radiology (F.R., P.d.G., M.C.d.J., J.A.C.)
| | - P de Graaf
- From the Departments of Radiology (F.R., P.d.G., M.C.d.J., J.A.C.)
| | | | | | - A Cerase
- Neuroimaging and Neurointerventional Unit (A.C., P.G.)
| | - P Toti
- Pathology (P.T.), Azienda Ospedaliera e Universitaria, Santa Maria alle Scotte, Siena, Italy
| | - M C de Jong
- From the Departments of Radiology (F.R., P.d.G., M.C.d.J., J.A.C.)
| | - A C Moll
- Ophthalmology (A.C.M.), VU University Medical Center, Amsterdam, the Netherlands
| | - J A Castelijns
- From the Departments of Radiology (F.R., P.d.G., M.C.d.J., J.A.C.)
| | - P Galluzzi
- Neuroimaging and Neurointerventional Unit (A.C., P.G.)
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356
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Li XS, Fan HX, Fang H, Song YL, Zhou CW. Value of R2* obtained from T2*-weighted imaging in predicting the prognosis of advanced cervical squamous carcinoma treated with concurrent chemoradiotherapy. J Magn Reson Imaging 2015; 42:681-8. [PMID: 25581675 DOI: 10.1002/jmri.24837] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/11/2014] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND To prospectively investigate the value of R2* in predicting the prognosis of advanced cervical squamous carcinoma treated with concurrent chemoradiotherapy. METHODS Sixty-five patients with biopsy-proven cervical squamous carcinoma were enrolled in our study. All these subjects underwent multi-echo T2*-weighted MR imaging on a 3.0 Tesla MR scanner, and tumor R2* was calculated. The patients were divided into the responders and the nonresponders according to treatment effect. Tumor R2* values of these two groups were compared. The relationship between tumor R2* and prognosis after therapy was analyzed. RESULTS The responder group had lower R2* value than the nonresponder group (P = 0.02). The area under the receiver operating characteristics curve for tumor R2* in discriminating responders from nonresponders was 0.769. A cutoff value of 23.87 Hz for tumor R2* resulted in a sensitivity of 78.3% and a specificity of 67.6%. The low R2* group (≤28.37 Hz) had longer median progression-free survival period and overall survival period (P = 0.01, 0.03). Multivariate analysis showed that tumor R2* was a significant prognostic factor for progression-free survival and overall survival (adjusted hazards ratio = 5.34, 4.78; P = 0.02, 0.01). CONCLUSION R2* value obtained from T2*-weighted imaging, as an imaging biomarker, may be an important predictor for the prognosis of advanced cervical squamous carcinoma treated with concurrent chemoradiotherapy.
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Affiliation(s)
- Xiang Sheng Li
- Department of MRI, Air Force General Hospital, People's Liberation Army, Beijing, China
| | - Hong Xia Fan
- Department of MRI, Air Force General Hospital, People's Liberation Army, Beijing, China
| | - Hong Fang
- Department of MRI, Air Force General Hospital, People's Liberation Army, Beijing, China
| | - Yun Long Song
- Department of MRI, Air Force General Hospital, People's Liberation Army, Beijing, China
| | - Chun Wu Zhou
- Department of Radiology, Cancer Hospital, Chinese Academy of Medical Sciences, Beijing, China
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357
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Larsen B, Luna B. In vivo evidence of neurophysiological maturation of the human adolescent striatum. Dev Cogn Neurosci 2014; 12:74-85. [PMID: 25594607 PMCID: PMC4385446 DOI: 10.1016/j.dcn.2014.12.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 12/17/2014] [Accepted: 12/18/2014] [Indexed: 12/22/2022] Open
Abstract
Maturation of the striatum has been posited to play a primary role in observed increases in adolescent sensation-seeking. However, evidence of neurophysiological maturation in the human adolescent striatum is limited. We applied T2*-weighted imaging, reflecting indices of tissue-iron concentration, to provide direct in vivo evidence of neurophysiological development of the human adolescent striatum. Multivariate pattern analysis (MVPA) of striatal T2*-weighted signal generated age predictions that accounted for over 60% of the sample variance in 10-25 year olds, using both task-related and resting state fMRI. Dorsal and ventral striatum showed age related increases and decreases respectively of striatal neurophysiology suggesting qualitative differences in the maturation of limbic and executive striatal systems. In particular, the ventral striatum was found to show the greatest developmental differences and contribute most heavily to the multivariate age predictor. The relationship of the T2*-weighted signal to the striatal dopamine system is discussed. Together, results provide evidence for protracted maturation of the striatum through adolescence.
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Affiliation(s)
- Bart Larsen
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Center for the Neural Basis of Cognition, Pittsburgh, PA 15213, USA.
| | - Beatriz Luna
- Department of Psychology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Center for the Neural Basis of Cognition, Pittsburgh, PA 15213, USA; Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA
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358
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Belaïch R, Boujraf S, Housni A, Maaroufi M, Batta F, Magoul R, Sqalli T, Errasfa M, Tizniti S. Assessment of hemodialysis impact by Polysulfone membrane on brain plasticity using BOLD-fMRI. Neuroscience 2014; 288:94-104. [PMID: 25522721 DOI: 10.1016/j.neuroscience.2014.11.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 10/21/2014] [Accepted: 11/23/2014] [Indexed: 11/26/2022]
Abstract
PURPOSE Hemodialysis (HD) is considered the most common alternative for overcoming renal failure. Studies have shown the involvement of HD membrane in the genesis of oxidative stress (OS) which has a direct impact on the brain tissue and is expected to be involved in brain plasticity and also reorganization of brain function control. The goal of this paper was to demonstrate the sensitivity of the blood oxygenation level-dependent functional magnetic resonance imaging (BOLD-fMRI) to characterize the OS before and after the HD session. PATIENTS, MATERIALS AND METHODS Twelve male patient-volunteers following chronic HD for more than 6months were recruited among 86 HD-patients. All patients underwent identical assessment immediately before and after the full HD-session. This consisted of full biological assessment, including malondialdehyde (MDA) and total antioxidant activity (TAOA); and brain BOLD-fMRI using the motor paradigm in block-design. RESULTS Functional BOLD-fMRI maps of motor area M1 were obtained from the HD patient before and after the hemodialysis session, important decrease in the intensity of brain activation of the motor area after HD, and important increase of the size of the volume of brain activation were observed, these changes are reflecting brain plasticity that is well correlated to OS levels. Individual patients MDA and TAOA before and after the hemodialysis sessions demonstrated a clear and systematic increase of the OS after HD (P-value=0.03). Correlation of BOLD-fMRI maximal signal intensity and volume of activated cortical brain area behaviors to MDA and total TAOA were close to 1. CONCLUSION OS is systematically increased in HD-patients after the HD-process. Indeed, the BOLD-fMRI shows a remarkable sensitivity to brain plasticity studied cortical areas. Our results confirm the superiority of the BOLD-fMRI quantities compared to the biological method used for assessing the OS while not being specific, and reflect the increase in OS generated by the HD. BOLD-fMRI is expected to be a suitable tool for evaluating the plasticity process evolution in hemodialysis brain patients.
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Affiliation(s)
- R Belaïch
- Department of Biophysics and Clinical MRI Methods, Faculty of Medicine, Fez, Morocco; The Clinical Neuroscience Laboratory, Faculty of Medicine, Fez, Morocco
| | - S Boujraf
- Department of Biophysics and Clinical MRI Methods, Faculty of Medicine, Fez, Morocco; The Clinical Neuroscience Laboratory, Faculty of Medicine, Fez, Morocco.
| | - A Housni
- The Clinical Neuroscience Laboratory, Faculty of Medicine, Fez, Morocco; Department of Radiology and Clinical Imaging, University Hospital of Fez, Fez, Morocco
| | - M Maaroufi
- The Clinical Neuroscience Laboratory, Faculty of Medicine, Fez, Morocco; Department of Radiology and Clinical Imaging, University Hospital of Fez, Fez, Morocco
| | - F Batta
- The Clinical Neuroscience Laboratory, Faculty of Medicine, Fez, Morocco; Department of Nephrology, University Hospital of Fez, Fez, Morocco
| | - R Magoul
- Laboratory of Neuroendocrinology and Nutritional and Climatic Environment, Faculty of Sciences Dhar El Mahraz, University Sidi Mohammed Ben Abdellah, Fez-Atlas, BP 1796, Fez, Morocco
| | - T Sqalli
- Department of Nephrology, University Hospital of Fez, Fez, Morocco
| | - M Errasfa
- Department of Pharmacology, Faculty of Medicine, University of Fez, Fez, Morocco; The Laboratory of Molecular Basis in Human Pathology and Therapeutical Tools, Faculty of Medicine, University of Fez, Fez, Morocco
| | - S Tizniti
- The Clinical Neuroscience Laboratory, Faculty of Medicine, Fez, Morocco; Department of Radiology and Clinical Imaging, University Hospital of Fez, Fez, Morocco
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359
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Alexiou E. Methodologies and Tools Used Today for Measuring Iron Load. THALASSEMIA REPORTS 2014. [DOI: 10.4081/thal.2014.4861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Iron overload is a matter of an extreme clinical importance, in the overall management of Thalassaemia. Magnetic Resonance Imaging (MRI), has evolved in a novel tool for iron quantification during the last decade and it is considered as a validated, accurate and noninvasive method with worldwide distribution. The MRI scanner exploits the intrinsic magnetic properties of the hydrogen nuclei in order to discriminate the tissue characteristics. The presence of iron in a tissue causes a faster dephasing of the protons and a reduction in T2* and T2. R2 and R2* represent the reciprocal of T2 and T2*. In order to measure the signal intensity and quantify iron concentration the Gradient Echo (GRE) T2* and the Spin Echo (SE) T2 sequence are used. There are two broad groups of techniques to quantify the iron. The signal intensity ratio (SIR) methods and the relaxometry methods. The later are sub grouped in the R2 (T2) relaxometry methods with the predominant of this category being the FerriScan® and the R2* (T2*) methods. CMR Gradient Echo T2* pulse sequence is the preferred technique for the quantification of iron in the heart. The R2 and R2* methodologies are both very accurate in predicting the true LIC with high levels of sensitivity and specificity in the range of clinically important LIC thresholds and can be both used over a wide clinical range, individually.
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360
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Noij DP, de Jong MC, Mulders LGM, Marcus JT, de Bree R, Lavini C, de Graaf P, Castelijns JA. Contrast-enhanced perfusion magnetic resonance imaging for head and neck squamous cell carcinoma: a systematic review. Oral Oncol 2014; 51:124-38. [PMID: 25467775 DOI: 10.1016/j.oraloncology.2014.10.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 10/26/2014] [Accepted: 10/29/2014] [Indexed: 12/21/2022]
Abstract
This systematic review gives an extensive overview of the current state of perfusion-weighted magnetic resonance imaging (MRI) for head and neck squamous cell carcinoma (HNSCC). Pubmed and Embase were searched for literature until July 2014 assessing the diagnostic and prognostic performance of perfusion-weighted MRI in HNSCC. Twenty-one diagnostic and 12 prognostic studies were included for qualitative analysis. Four studies used a T2(∗) sequence for dynamic susceptibility (DSC)-MRI, 29 studies used T1-based sequences for dynamic contrast enhanced (DCE)-MRI. Included studies suffered from a great deal of heterogeneity in study methods showing a wide range of diagnostic and prognostic performance. Therefore we could not perform any useful meta-analysis. Perfusion-weighted MRI shows potential in some aspects of diagnosing HNSCC and predicting prognosis. Three studies reported significant correlations between hypoxia and tumor heterogeneity in perfusion parameters (absolute correlation coefficient |ρ|>0.6, P<0.05). Two studies reported synergy between perfusion-weighted MRI and positron emission tomography (PET) parameters. Four studies showed a promising role for response prediction early after the start of chemoradiotherapy. In two studies perfusion-weighted MRI was useful in the detection of residual disease. However more research with uniform study and analysis protocols with larger sample sizes is needed before perfusion-weighted MRI can be used in clinical practice.
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Affiliation(s)
- Daniel P Noij
- Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
| | - Marcus C de Jong
- Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
| | - Lieven G M Mulders
- Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
| | - Johannes T Marcus
- Department of Physics and Medical Technology, VU University Medical Center, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
| | - Remco de Bree
- Department of Otolaryngology - Head and Neck Surgery, VU University Medical Center, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
| | - Cristina Lavini
- Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
| | - Pim de Graaf
- Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
| | - Jonas A Castelijns
- Department of Radiology and Nuclear Medicine, VU University Medical Center, De Boelelaan 1117, PO Box 7057, 1007 MB Amsterdam, The Netherlands.
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361
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Govindarajan ST, Cohen-Adad J, Sormani MP, Fan AP, Louapre C, Mainero C. Reproducibility of T2 * mapping in the human cerebral cortex in vivo at 7 tesla MRI. J Magn Reson Imaging 2014; 42:290-6. [PMID: 25407671 DOI: 10.1002/jmri.24789] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 10/16/2014] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND To assess the test-retest reproducibility of cortical mapping of T2 * relaxation rates at 7 Tesla (T) MRI. T2 * maps have been used for studying cortical myelo-architecture patterns in vivo and for characterizing conditions associated with changes in iron and/or myelin concentration. METHODS T2 * maps were calculated from 7T multi-echo T2 *-weighted images acquired during separate scanning sessions on 8 healthy subjects. The reproducibility of surface-based cortical T2 * mapping was assessed at different depths of the cortex; from pial surface (0% depth) towards gray/white matter boundary (100% depth), across cortical regions and hemispheres, using coefficients of variation (COVs = SD/mean) between each couple (scan-rescan) of average T2 * measurements. RESULTS Average cortical T2 * was significantly different among 25%, 50%, and 75% depths (analysis of variance, P < 0.001). Coefficient of variations were very low within cortical regions, and whole cortex (average COV = 0.83-1.79%), indicating a high degree of reproducibility in T2 * measures. CONCLUSION Surface-based mapping of T2 * relaxation rates as a function of cortical depth is reproducible and could prove useful for studying the laminar architecture of the cerebral cortex in vivo, and for investigating physiological and pathological states associated with changes in iron and/or myelin concentration.
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Affiliation(s)
| | - Julien Cohen-Adad
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA.,Institute of Biomedical Engineering, Polytechnique Montreal, Montreal, QC, Canada
| | | | - Audrey P Fan
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA.,Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Céline Louapre
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Caterina Mainero
- Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA.,Harvard Medical School, Boston, Massachusetts, USA
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362
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Romanenko K, Jin L, Madsen LA, Pringle JM, O’Dell LA, Forsyth M. Anisotropic MRI Contrast Reveals Enhanced Ionic Transport in Plastic Crystals. J Am Chem Soc 2014; 136:15638-45. [PMID: 25312993 DOI: 10.1021/ja508290z] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Konstantin Romanenko
- Institute
for Frontier Materials, Deakin University, Waurn Ponds Campus, 75 Pigdons Road, Geelong, Victoria 3220, Australia
| | - Liyu Jin
- ARC
Centre of Excellence for Electromaterials Science, Deakin University, Burwood Campus, 221 Burwood Highway, Burwood, Victoria 3125, Australia
- Department
of Materials Engineering, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
| | - Louis A. Madsen
- Department
of Chemistry and Macromolecules and Interfaces Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Jennifer M. Pringle
- Institute
for Frontier Materials, Deakin University, Waurn Ponds Campus, 75 Pigdons Road, Geelong, Victoria 3220, Australia
- ARC
Centre of Excellence for Electromaterials Science, Deakin University, Burwood Campus, 221 Burwood Highway, Burwood, Victoria 3125, Australia
| | - Luke A. O’Dell
- Institute
for Frontier Materials, Deakin University, Waurn Ponds Campus, 75 Pigdons Road, Geelong, Victoria 3220, Australia
| | - Maria Forsyth
- Institute
for Frontier Materials, Deakin University, Waurn Ponds Campus, 75 Pigdons Road, Geelong, Victoria 3220, Australia
- ARC
Centre of Excellence for Electromaterials Science, Deakin University, Burwood Campus, 221 Burwood Highway, Burwood, Victoria 3125, Australia
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Abstract
This review describes and discusses the rationale, technique, applications, and impact of cardiovascular magnetic resonance (CMR) T2* imaging, principally in the assessment of iron loading within the heart, and highlights how this robust imaging strategy has transformed disease outcome.Until recently, no simple noninvasive measurement was available to reliably indicate severe cardiac iron loading before the development of overt cardiac dysfunction or heart failure. Consequently, the majority of patients with transfusion-dependent anemias, such as β-thalassemia major, died prematurely of cardiovascular complications of severe iron overload.The magnetic properties of particulate iron disrupt magnetic field homogeneity in the CMR environment and consequently influence the CMR parameter T2*, which describes signal decay relating to both field inhomogeneity and loss of spin coherence. There is a direct relationship between T2* and myocardial iron concentration, enabling this to be used to identify and quantify myocardial iron load. Single breath-hold gradient-echo sequences in which a single midventricular short-axis myocardial slice is acquired at multiple echo times enables a myocardial T2* value to be measured from the rate of exponential decay. The application of T2* CMR to assessing cardiac iron loading is rapid, reproducible, extensively validated, and now widely performed. Data have highlighted the profound predictive power of this imaging technique and moreover its ability to inform management strategies such that, over a relatively short duration, outcome has been dramatically improved, and the disease course in β-thalassemia major transformed.
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364
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Trachtenberg JE, Vo TN, Mikos AG. Pre-clinical characterization of tissue engineering constructs for bone and cartilage regeneration. Ann Biomed Eng 2014; 43:681-96. [PMID: 25319726 DOI: 10.1007/s10439-014-1151-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/06/2014] [Indexed: 12/16/2022]
Abstract
Pre-clinical animal models play a crucial role in the translation of biomedical technologies from the bench top to the bedside. However, there is a need for improved techniques to evaluate implanted biomaterials within the host, including consideration of the care and ethics associated with animal studies, as well as the evaluation of host tissue repair in a clinically relevant manner. This review discusses non-invasive, quantitative, and real-time techniques for evaluating host-materials interactions, quality and rate of neotissue formation, and functional outcomes of implanted biomaterials for bone and cartilage tissue engineering. Specifically, a comparison will be presented for pre-clinical animal models, histological scoring systems, and non-invasive imaging modalities. Additionally, novel technologies to track delivered cells and growth factors will be discussed, including methods to directly correlate their release with tissue growth.
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Affiliation(s)
- Jordan E Trachtenberg
- Department of Bioengineering, Rice University, MS 142, P.O. Box 1892, Houston, TX, 77251-1892, USA
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365
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Hesper T, Hosalkar HS, Bittersohl D, Welsch GH, Krauspe R, Zilkens C, Bittersohl B. T2* mapping for articular cartilage assessment: principles, current applications, and future prospects. Skeletal Radiol 2014; 43:1429-45. [PMID: 24643762 DOI: 10.1007/s00256-014-1852-3] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 02/08/2014] [Accepted: 02/17/2014] [Indexed: 02/02/2023]
Abstract
With advances in joint preservation surgery that are intended to alter the course of osteoarthritis by early intervention, accurate and reliable assessment of the cartilage status is critical. Biochemically sensitive MRI techniques can add robust biomarkers for disease onset and progression, and therefore, could be meaningful assessment tools for the diagnosis and follow-up of cartilage abnormalities. T2* mapping could be a good alternative because it would combine the benefits of biochemical cartilage evaluation with remarkable features including short imaging time and the ability of high-resolution three-dimensional cartilage evaluation-without the need for contrast media administration or special hardware. Several in vitro and in vivo studies, which have elaborated on the potential of cartilage T2* assessment in various cartilage disease patterns and grades of degeneration, have been reported. However, much remains to be understood and certain unresolved questions have become apparent with these studies that are crucial to the further application of this technique. This review summarizes the principles of the technique and current applications of T2* mapping for articular cartilage assessment. Limitations of recent studies are discussed and the potential implications for patient care are presented.
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Affiliation(s)
- Tobias Hesper
- Department of Orthopaedics Medical Faculty, University Düsseldorf, Düsseldorf, Germany
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366
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Yang XZ, Ni J, Cui LY. Multifocal hemosiderin depositions on T2*-weighted magnetic resonance imaging in a patient with pathology-proven systemic diffuse large B-cell lymphoma. BMC Neurol 2014; 14:184. [PMID: 25252760 PMCID: PMC4180546 DOI: 10.1186/s12883-014-0184-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Accepted: 09/11/2014] [Indexed: 12/26/2022] Open
Abstract
Background Intracranial hemorrhage in central nervous system lymphoma is extremely rare. T2*-weighted gradient-echo magnetic resonance imaging is of particularly use in detecting silent hemorrhage as hypointense signals due to the deposition of paramagnetic hemosiderin or mineralization. Multifocal hemosiderin depositions caused by chronic silent hemorrhage have not yet been identified in patients with central nervous system involvement of systemic lymphoma. We present an unexpected radiographic feature on T2*-weighted gradient-echo magnetic resonance imaging in a patient with central nervous system involvement of pathologically confirmed systemic diffuse large B-cell lymphoma. Case presentation A 56-year-old woman presented with lower extremities weakness and progressive cognitive decline for four months. Conventional brain magnetic resonance imaging demonstrated multiple lesions with hypointensities on T1-weighted images and hyperintensities on T2-weighted images and fluid attenuated inversion recovery in both hemispheres. She was then transferred to our hospital. Neurological examination showed impaired cognitive functions. Contrast-enhanced magnetic resonance imaging revealed irregular spotty enhancement within the lesions. T2*-weighted gradient-echo magnetic resonance imaging revealed diffuse hemosiderin depositions with hypointensities mostly adjacent to the cortex, which are not compatible with the lesions visualized on T1-weighted images. Whole body positron emission tomography/computed tomography scanning showed multiple hyper-metabolic foci in the pelvic cavity and the spleen. The pathological diagnosis of the biopsy specimen was consistent with diffuse large B-cell lymphoma. Conclusion This is the first report of pathologically confirmed case of CNS involvement of systemic diffuse large B-cell lymphoma with multifocal silent hemosiderin depositions detected by T2*-weighted gradient-echo magnetic resonance imaging. Even though uncommon, our report offers an insight that CNS lymphoma could present with multifocal silent hemosiderin depositions on T2*-weighted gradient-echo magnetic resonance imaging. Further studies were expected for exploring the association between this radiologic feature and systemic lymphoma and their underlying mechanisms.
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367
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Fei X, Li S, Gao S, Wei L, Wang L. Application safety evaluation of the radio frequency identification tag under magnetic resonance imaging. Biomed Eng Online 2014; 13:129. [PMID: 25187420 PMCID: PMC4175226 DOI: 10.1186/1475-925x-13-129] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 08/30/2014] [Indexed: 11/29/2022] Open
Abstract
Background Radio Frequency Identification(RFID) has been widely used in healthcare facilities, but it has been paid little attention whether RFID applications are safe enough under healthcare environment. The purpose of this study is to assess the effects of RFID tags on Magnetic Resonance (MR) imaging in a typical electromagnetic environment in hospitals, and to evaluate the safety of their applications. Methods A Magphan phantom was used to simulate the imaging objects, while active RFID tags were placed at different distances (0, 4, 8, 10 cm) from the phantom border. The phantom was scanned by using three typical sequences including spin-echo (SE) sequence, gradient-echo (GRE) sequence and inversion-recovery (IR) sequence. The quality of the image was quantitatively evaluated by using signal-to-noise ratio (SNR), uniformity, high-contrast resolution, and geometric distortion. RFID tags were read by an RFID reader to calculate their usable rate. Results RFID tags can be read properly after being placed in high magnetic field for up to 30 minutes. SNR: There were no differences between the group with RFID tags and the group without RFID tags using SE and IR sequence, but it was lower when using GRE sequence.Uniformity: There was a significant difference between the group with RFID tags and the group without RFID tags using SE and GRE sequence. Geometric distortion and high-contrast resolution: There were no obvious differences found. Conclusions Active RFID tags can affect MR imaging quality, especially using the GRE sequence. Increasing the distance from the RFID tags to the imaging objects can reduce that influence. When the distance was longer than 8 cm, MR imaging quality were almost unaffected. However, the Gradient Echo related sequence is not recommended when patients wear a RFID wristband.
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Affiliation(s)
| | | | | | | | - Lihong Wang
- Information Management Office, Xuanwu Hospital Capital Medical University, No, 45 Changchun Street, Beijing 100053, China.
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368
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Gupta H, Paul P, Kumar N, Baxi S, Das DP. One pot synthesis of water-dispersible dehydroascorbic acid coated Fe3O4 nanoparticles under atmospheric air: Blood cell compatibility and enhanced magnetic resonance imaging. J Colloid Interface Sci 2014; 430:221-8. [DOI: 10.1016/j.jcis.2014.05.043] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 05/12/2014] [Accepted: 05/17/2014] [Indexed: 11/25/2022]
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369
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Survival analysis in patients with newly diagnosed primary glioblastoma multiforme using pre- and post-treatment peritumoral perfusion imaging parameters. J Neurooncol 2014; 120:361-70. [PMID: 25098699 DOI: 10.1007/s11060-014-1560-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 07/21/2014] [Indexed: 10/24/2022]
Abstract
The objective of this study was to evaluate if peritumoral (PT) perfusion parameters obtained from dynamic susceptibility weighted contrast enhanced perfusion MRI can predict overall survival (OS) and progression free survival (PFS) in patients with newly diagnosed glioblastoma multiforme (GBM). Twenty-eight newly diagnosed GBM patients, who were treated with resection followed by concurrent chemoradiation and adjuvant chemotherapy, were included in this study. Evaluated perfusion parameters were pre- and post-treatment PT relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF). Proportional hazard analysis was used to assess the relationship OS, PFS and perfusion parameters. Kaplan-Meier survival estimates and log-rank test were used to characterize and compare the patient groups with high and low perfusion parameter values in terms of OS and PFS. Pretreatment PT rCBV and rCBF were not associated with OS and PFS whereas there was statistically significant association of both posttreatment PT rCBV and rCBF with OS and posttreatment rCBV with PFS (association of PFS and posttreatment rCBF was not statistically significant). Neither the Kaplan-Meier survival estimates nor the log-rank test demonstrated any differences in OS between high and low pretreatment PT rCBV values and rCBF values; however, high and low post-treatment PT rCBV and rCBF values did demonstrate statistically significant difference in OS and PFS. Our study found posttreatment, not pretreatment, PT perfusion parameters can be used to predict OS and PFS in patients with newly diagnosed GBM.
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370
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Ellingson AM, Nagel TM, Polly DW, Ellermann J, Nuckley DJ. Quantitative T2* (T2 star) relaxation times predict site specific proteoglycan content and residual mechanics of the intervertebral disc throughout degeneration. J Orthop Res 2014; 32:1083-9. [PMID: 24788830 PMCID: PMC4136382 DOI: 10.1002/jor.22633] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 03/28/2014] [Indexed: 02/04/2023]
Abstract
Degeneration alters the biochemical composition of the disc, affecting the mechanical integrity leading to spinal instability. Quantitative T2* MRI probes water mobility within the macromolecular network, a potentially more sensitive assessment of disc health. We determined the relationship between T2* relaxation time and proteoglycan content, collagen content, and compressive mechanics throughout the degenerative spectrum. Eighteen human cadaveric lumbar (L4-L5) discs were imaged using T2* MRI. The T2* relaxation time at five locations (nucleous pulposus or NP, anterior annulus fibrosis or AF, posterior AF, inner AF, and outer AF) was correlated with sulfated-glycosaminoglycan (s-GAG) content, hydroxyproline content, and residual stress and strain at each location. T2* relaxation times were significantly correlated with s-GAG contents in all test locations and were particularly strong in the NP (r = 0.944; p < 0.001) and inner AF (r = 0.782; p < 0.001). T2* relaxation times were also significantly correlated with both residual stresses and excised strains in the NP (r = 0.857; p < 0.001: r = 0.816; p < 0.001), inner AF (r = 0.535; p = 0.022: r = 0.516; p = 0.028), and outer AF (r = 0.668; p = 0.002: r = 0.458; p = 0.041). These strong correlations highlight T2* MRI's ability to predict the biochemical and mechanical health of the disc. T2* MRI assessment of disc health is a clinically viable tool showing promise as a biomarker for distinguishing degenerative changes.
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Affiliation(s)
- Arin M. Ellingson
- Department of Biomedical Engineering, University of Minnesota, Nils Hasselmo Hall, Room 7-105, 312 Church Street S.E., Minneapolis, Minnesota
| | - Tina M. Nagel
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota
| | - David W. Polly
- Department of Orthopaedic Surgery, University of Minnesota, Minneapolis, Minnesota
| | - Jutta Ellermann
- Department of Radiology, Center for Magnetic Resonance Research, University of Minnesota, Minneapolis, Minnesota
| | - David J. Nuckley
- Department of Biomedical Engineering, University of Minnesota, Nils Hasselmo Hall, Room 7-105, 312 Church Street S.E., Minneapolis, Minnesota,Department of Physical Medicine and Rehabilitation, University of Minnesota, Minneapolis, Minnesota,Orthopaedic Biomechanics Laboratory, University of Minnesota, Minneapolis, Minnesota
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371
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Pilapong C, Sitthichai S, Thongtem S, Thongtem T. Smart magnetic nanoparticle-aptamer probe for targeted imaging and treatment of hepatocellular carcinoma. Int J Pharm 2014; 473:469-74. [PMID: 25089503 DOI: 10.1016/j.ijpharm.2014.07.036] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 07/09/2014] [Accepted: 07/25/2014] [Indexed: 12/21/2022]
Abstract
We report herein the development of a smart magnetic nanoparticle-aptamer probe, or theranostic nanoprobe, which can be used for targeted imaging and as a drug carrier for hepatocellular carcinoma treatment. The theranostic nanoprobe combines the delivery potential of a non-toxic cellulose derivative polymer, specific capability of cancer-specific molecule (DNA-based EpCAM aptamer) and the imaging capability of magnetic iron oxide nanoparticles. Our proof-of-concept design demonstrates efficient in vitro MR imaging of the cancer cells, and enhanced delivery of an anticancer drug into the cancer cells with comparable treatment efficacy.
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Affiliation(s)
- Chalermchai Pilapong
- Center of Excellence for Molecular Imaging (CEMI), Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand.
| | - Sudarat Sitthichai
- Department of Physics and Material Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Somchai Thongtem
- Department of Physics and Material Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Titipun Thongtem
- Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
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372
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Stephenson E, Nathoo N, Mahjoub Y, Dunn JF, Yong VW. Iron in multiple sclerosis: roles in neurodegeneration and repair. Nat Rev Neurol 2014; 10:459-68. [PMID: 25002107 DOI: 10.1038/nrneurol.2014.118] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
MRI and histological studies have shown global alterations in iron levels in the brains of patients with multiple sclerosis (MS), including increases in the iron stored by macrophages and microglia. Excessive free iron can be toxic, and accumulation of iron in MS has generally been thought to be detrimental. However, iron maintains the integrity of oligodendrocytes and myelin, and facilitates their regeneration following injury. The extracellular matrix, a key regulator of remyelination, might also modulate iron levels. This Review highlights key histological and MRI studies that have investigated changes in iron distribution associated with MS. Potential sources of iron, as well as iron regulatory proteins and the detrimental roles of excessive iron within the CNS, are also discussed, with emphasis on the importance of iron within cells for oxidative metabolism, proliferation and differentiation of oligodendrocytes, and myelination. In light of the beneficial and detrimental properties of iron within the CNS, we present considerations for treatments that target iron in MS. Such treatments must balance trophic and toxic properties of iron, by providing sufficient iron levels for remyelination and repair while avoiding excesses that might overwhelm homeostatic mechanisms and contribute to damage.
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Affiliation(s)
- Erin Stephenson
- Hotchkiss Brain Institute and the Department of Clinical Neurosciences, University of Calgary, Health Medical Research Centre, Room 187, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
| | - Nabeela Nathoo
- Hotchkiss Brain Institute and the Department of Clinical Neurosciences, University of Calgary, Health Medical Research Centre, Room 187, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
| | - Yasamin Mahjoub
- Hotchkiss Brain Institute and the Department of Clinical Neurosciences, University of Calgary, Health Medical Research Centre, Room 187, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
| | - Jeff F Dunn
- Hotchkiss Brain Institute and the Department of Clinical Neurosciences, University of Calgary, Health Medical Research Centre, Room 187, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
| | - V Wee Yong
- Hotchkiss Brain Institute and the Department of Clinical Neurosciences, University of Calgary, Health Medical Research Centre, Room 187, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
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Alomair OI, Smith MT, Brereton IM, Galloway GJ, Kurniawan ND. Current developments in MRI for assessing rodent models of multiple sclerosis. FUTURE NEUROLOGY 2014. [DOI: 10.2217/fnl.14.33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
ABSTRACT: MRI is a key radiological imaging technique that plays an important role in the diagnosis and characterization of heterogeneous multiple sclerosis (MS) lesions. Various MRI methodologies such as conventional T 1/T 2 contrast, contrast agent enhancement, diffusion-weighted imaging, magnetization transfer imaging and susceptibility weighted imaging have been developed to determine the severity of MS pathology, including demyelination/remyelination and brain connectivity impairment from axonal loss. The broad spectrum of MS pathology manifests in diverse patient MRI presentations and affects the accuracy of patient diagnosis. To study specific pathological aspects of the disease, rodent models such as experimental autoimmune encephalomyelitis, virus-induced and toxin-induced demyelination have been developed. This review aims to present key developments in MRI methodology for better characterization of rodent models of MS.
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Affiliation(s)
- Othman I Alomair
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
- College of Applied Medical Science, King Saud University, Riyadh, Saudi Arabia
| | - Maree T Smith
- School of Pharmacy, The University of Queensland, Brisbane, Queensland, Australia
- Centre for Integrated Preclinical Drug Development, The University of Queensland, Brisbane, Queensland, Australia
| | - Ian M Brereton
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
| | - Graham J Galloway
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
| | - Nyoman D Kurniawan
- Centre for Advanced Imaging, University of Queensland, Brisbane, Queensland, Australia
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374
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Kranz PG, Amrhein TJ, Provenzale JM. Spontaneous brain parenchymal hemorrhage: an approach to imaging for the emergency room radiologist. Emerg Radiol 2014; 22:53-63. [PMID: 24894555 DOI: 10.1007/s10140-014-1245-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 05/26/2014] [Indexed: 01/14/2023]
Abstract
Spontaneous intracranial hemorrhage is a neurological emergency commonly encountered by the emergency radiologist. This article reviews the approach to spontaneous brain parenchymal hemorrhage, including common causes and the role of various neuroimaging modalities in the diagnostic workup. We emphasize the need for a primary survey directed at conveying information needed for emergent clinical management of the patient and a secondary survey directed at identifying the etiology of the hemorrhage.
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Affiliation(s)
- Peter G Kranz
- Department of Radiology, Duke University Medical Center, Durham, NC, USA,
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375
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Stüber C, Morawski M, Schäfer A, Labadie C, Wähnert M, Leuze C, Streicher M, Barapatre N, Reimann K, Geyer S, Spemann D, Turner R. Myelin and iron concentration in the human brain: A quantitative study of MRI contrast. Neuroimage 2014; 93 Pt 1:95-106. [DOI: 10.1016/j.neuroimage.2014.02.026] [Citation(s) in RCA: 435] [Impact Index Per Article: 43.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 01/25/2014] [Accepted: 02/25/2014] [Indexed: 12/28/2022] Open
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376
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McDevitt JL, Mouli SK, Tyler PD, Li W, Nicolai J, Procissi D, Ragin AB, Wang YA, Lewandowski RJ, Salem R, Larson AC, Omary RA. MR imaging enables measurement of therapeutic nanoparticle uptake in rat N1-S1 liver tumors after nanoablation. J Vasc Interv Radiol 2014; 25:1288-94. [PMID: 24854392 DOI: 10.1016/j.jvir.2014.03.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 03/28/2014] [Accepted: 03/30/2014] [Indexed: 12/01/2022] Open
Abstract
PURPOSE To test the hypothesis that magnetic resonance (MR) imaging can quantify intratumoral superparamagnetic iron oxide (SPIO) nanoparticle uptake after nanoablation. MATERIALS AND METHODS SPIO nanoparticles functionalized with doxorubicin were synthesized. N1-S1 hepatomas were successfully induced in 17 Sprague-Dawley rats distributed into three dosage groups. Baseline tumor R2* values (the reciprocal of T2*) were determined using 7-tesla (T) MR imaging. After intravenous injection of SPIO nanoparticles, reversible electroporation (1,300 V/cm, 8 pulses, 100-μs pulse duration) was applied. Imaging of rats was performed to determine tumor R2* values after the procedure, and change in R2* (ΔR2*) was calculated. Inductively coupled plasma mass spectrometry was used to determine intratumoral iron (Fe) concentration after the procedure, which served as a proxy for SPIO nanoparticle uptake. Mean tumor Fe concentration [Fe] and ΔR2* for each subject were assessed for correlation with linear regression, and mean [Fe] for each dosage group was compared with analysis of variance. RESULTS ΔR2* significantly correlated with tumor SPIO nanoparticle uptake after nanoablation (r = 0.50, P = .039). On average, each 0.1-ms(-1) increase in R2* corresponded to a 0.1394-mM increase in [Fe]. There was no significant difference in mean SPIO nanoparticle uptake among dosage groups (P = .57). CONCLUSIONS Intratumoral SPIO nanoparticle uptake after nanoablation can be successfully quantified noninvasively with 7-T MR imaging. Imaging can be used as a method to estimate localized drug delivery after nanoablation.
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Affiliation(s)
| | - Samdeep K Mouli
- Department of Radiology, Northwestern University, Chicago, Illinois
| | - Patrick D Tyler
- Department of Radiology, Northwestern University, Chicago, Illinois
| | - Weiguo Li
- Department of Radiology, Northwestern University, Chicago, Illinois
| | - Jodi Nicolai
- Department of Radiology, Northwestern University, Chicago, Illinois
| | - Daniele Procissi
- Department of Radiology, Northwestern University, Chicago, Illinois
| | - Ann B Ragin
- Department of Radiology, Northwestern University, Chicago, Illinois
| | | | - Robert J Lewandowski
- Department of Radiology, Northwestern University, Chicago, Illinois; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois
| | - Riad Salem
- Department of Radiology, Northwestern University, Chicago, Illinois; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois
| | - Andrew C Larson
- Department of Radiology, Northwestern University, Chicago, Illinois; Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois; Department of Biomedical Engineering, Northwestern University, Evanston, Illinois
| | - Reed A Omary
- Department of Radiology and Radiological Sciences, Vanderbilt School of Medicine, 1611 21st Avenue South, CCC-1106 MCN, Nashville, TN 37232.
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Cerebral staging of lung cancer: is one single contrast-enhanced T1-weighted three-dimensional gradient-echo sequence sufficient? Neuroradiology 2014; 56:621-7. [PMID: 24829164 DOI: 10.1007/s00234-014-1366-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Accepted: 04/08/2014] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Gadolinium-enhanced magnetic resonance imaging (MRI) is the gold standard for cerebral staging in thoracic oncology. We hypothesize that a minimalist examination, consisting of a single contrast-enhanced T1-weighted three-dimensional gradient-echo sequence (CE 3D-GRE), would be sufficient for the cerebral staging of nonsymptomatic lung cancer patients. METHODS Seventy nonsymptomatic patients (50 % men; 62 years ± 10.2) referred for cerebral staging of a lung cancer were retrospectively included. All underwent a standard 3 T MRI examination with T1, FLAIR, T2* GRE, diffusion, and CE 3D-GRE sequences, for a total examination time of 20 min. The sole CE 3D-GRE (acquisition time: 6 min) was extracted and blindly interpreted by two radiologists in search of brain metastases. Hemorrhagic features of potential lesions and relevant incidental findings were also noted. Discrepant cases were reviewed by a third reader. The full MRI examination and follow-up studies were used as a reference to calculate sensitivity and specificity of the sole CE 3D-GRE. RESULTS Thirty-eight point six percent (27 out of 70) of the patients had brain metastases. Performances and reader's agreement with the sole CE 3D-GRE sequence were excellent for the diagnosis of brain metastases (sensitivity=96.3 %, specificity=100 %, κ=0.91) and incidental findings (sensitivity=85.7 %, specificity=100 %, κ=0.62) but insufficient for the identification of hemorrhages within the metastases (sensitivity=33.3 %, specificity=85.7 %, κ=0.47). CONCLUSIONS In the specific case of lung cancer, cerebral staging in nonsymptomatic patients can be efficiently achieved with a minimalistic protocol consisting of a single CE 3D-GRE sequence, completed if positive with a T2* sequence for hemorrhagic assessment, thus halving appointment delays.
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Ellermann J, Ziegler C, Nissi MJ, Goebel R, Hughes J, Benson M, Holmberg P, Morgan P. Acetabular Cartilage Assessment in Patients with Femoroacetabular Impingement by Using T2* Mapping with Arthroscopic Verification. Radiology 2014; 271:512-23. [DOI: 10.1148/radiol.13131837] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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379
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Habibollahi P, Waldron T, Heidari P, Cho HS, Alcantara D, Josephson L, Wang TC, Rustgi AK, Mahmood U. Fluorescent Nanoparticle Imaging Allows Noninvasive Evaluation of Immune Cell Modulation in Esophageal Dysplasia. Mol Imaging 2014. [DOI: 10.2310/7290.2014.00003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Peiman Habibollahi
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
| | - Todd Waldron
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
| | - Pedram Heidari
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
| | - Hoon Sung Cho
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
| | - David Alcantara
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
| | - Lee Josephson
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
| | - Timothy C. Wang
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
| | - Anil K. Rustgi
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
| | - Umar Mahmood
- From the Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA; Division of Gastroenterology, Departments of Medicine and Genetics, Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA; and Division of Digestive and Liver Diseases, Department of Medicine, and Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY
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380
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Tang MY, Chen TW, Zhang XM, Huang XH. GRE T2∗-weighted MRI: principles and clinical applications. BIOMED RESEARCH INTERNATIONAL 2014; 2014:312142. [PMID: 24987676 PMCID: PMC4009216 DOI: 10.1155/2014/312142] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 03/19/2014] [Indexed: 12/20/2022]
Abstract
The sequence of a multiecho gradient recalled echo (GRE) T2*-weighted imaging (T2*WI) is a relatively new magnetic resonance imaging (MRI) technique. In contrast to T2 relaxation, which acquires a spin echo signal, T2* relaxation acquires a gradient echo signal. The sequence of a GRE T2*WI requires high uniformity of the magnetic field. GRE T2*WI can detect the smallest changes in uniformity in the magnetic field and can improve the rate of small lesion detection. In addition, the T2* value can indirectly reflect changes in tissue biochemical components. Moreover, it can be used for the early diagnosis and quantitative diagnosis of some diseases. This paper reviews the principles and clinical applications as well as the advantages and disadvantages of GRE T2*WI.
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Affiliation(s)
- Meng Yue Tang
- Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China
| | - Tian Wu Chen
- Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China
| | - Xiao Ming Zhang
- Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China
| | - Xiao Hua Huang
- Sichuan Key Laboratory of Medical Imaging, Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan 637000, China
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381
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Biercevicz AM, Murray MM, Walsh EG, Miranda DL, Machan JT, Fleming BC. T2 * MR relaxometry and ligament volume are associated with the structural properties of the healing ACL. J Orthop Res 2014; 32:492-9. [PMID: 24338640 PMCID: PMC3946219 DOI: 10.1002/jor.22563] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 11/19/2013] [Indexed: 02/04/2023]
Abstract
Our objective was to develop a non-invasive magnetic resonance (MR) method to predict the structural properties of a healing anterior cruciate ligament (ACL) using volume and T2 * relaxation time. We also compared our T2 *-based structural property prediction model to a previous model utilizing signal intensity, an acquisition-dependent variable. Surgical ACL transection followed by no treatment (i.e., natural healing) or bio-enhanced ACL repair was performed in a porcine model. After 52 weeks of healing, high-resolution MR images of the ACL tissue were collected. From these images, ligament volumes and T2 * maps were established. The structural properties of the ligaments were determined via tensile testing. Using the T2 * histogram profile, each ligament voxel was binned based on its T2 * value into four discrete tissue sub-volumes defined by specific T2 * intervals. The linear combination of the ligament sub-volumes binned by T2 * value significantly predicted maximum load, yield load, and linear stiffness (R(2) = 0.92, 0.82, 0.88; p < 0.001) and were similar to the previous signal intensity based method. In conclusion, the T2 * technique offers a highly predictive methodology that is a first step towards the development of a method that can be used to assess ligament healing across scanners, studies, and institutions.
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Affiliation(s)
- Alison M. Biercevicz
- Department of Orthopaedics, Warren Alpert Medical School, Brown University/Rhode Island Hospital, Providence, RI
| | - Martha M. Murray
- Department of Orthopaedic Surgery, Boston Children's Hospital, Boston, MA
| | - Edward G. Walsh
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, RI
| | - Danny L. Miranda
- Department of Orthopaedics, Warren Alpert Medical School, Brown University/Rhode Island Hospital, Providence, RI
| | - Jason T. Machan
- Department of Orthopaedics, Warren Alpert Medical School, Brown University/Rhode Island Hospital, Providence, RI,Biostatistics, Rhode Island Hospital, Providence, RI
| | - Braden C. Fleming
- Department of Orthopaedics, Warren Alpert Medical School, Brown University/Rhode Island Hospital, Providence, RI,School of Engineering, Brown University, Providence, RI 02903
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Poulin É, Lebel R, Croteau É, Blanchette M, Tremblay L, Lecomte R, Bentourkia M, Lepage M. Optimization of the reference region method for dual pharmacokinetic modeling using Gd-DTPA/MRI and (18) F-FDG/PET. Magn Reson Med 2014; 73:740-8. [PMID: 24604379 DOI: 10.1002/mrm.25151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 01/07/2014] [Accepted: 01/08/2014] [Indexed: 11/06/2022]
Abstract
PURPOSE The combination of MRI and positron emission tomography (PET) offers new possibilities for the development of novel methodologies. In pharmacokinetic image analysis, the blood concentration of the imaging compound as a function of time, [i.e., the arterial input function (AIF)] is required for MRI and PET. In this study, we tested whether an AIF extracted from a reference region (RR) in MRI can be used as a surrogate for the manually sampled (18) F-FDG AIF for pharmacokinetic modeling. METHODS An MRI contrast agent, gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA) and a radiotracer, (18) F-fluorodeoxyglucose ((18) F-FDG), were simultaneously injected in a F98 glioblastoma rat model. A correction to the RR AIF for Gd-DTPA is proposed to adequately represent the manually sampled AIF. A previously published conversion method was applied to convert this AIF into a (18) F-FDG AIF. RESULTS The tumor metabolic rate of glucose (TMRGlc) calculated with the manually sampled (18) F-FDG AIF, the (18) F-FDG AIF converted from the RR AIF and the (18) F-FDG AIF converted from the corrected RR AIF were found not statistically different (P>0.05). CONCLUSION An AIF derived from an RR in MRI can be accurately converted into a (18) F-FDG AIF and used in PET pharmacokinetic modeling.
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Affiliation(s)
- Éric Poulin
- Centre d'imagerie moléculaire de Sherbrooke, Département de médecine nucléaire et radiobiologie, Université de Sherbrooke, Sherbrooke, Canada
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383
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Iron and atherosclerosis: nailing down a novel target with magnetic resonance. J Cardiovasc Transl Res 2014; 7:533-42. [PMID: 24590608 DOI: 10.1007/s12265-014-9551-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 02/14/2014] [Indexed: 12/21/2022]
Abstract
Iron is an essential mineral in many proteins and enzymes in human physiology, with limited means of iron elimination to maintain iron balance. Iron accrual incurs various pathological mechanisms linked to cardiovascular disease. In atherosclerosis, iron catalyzes the creation of reactive oxygen free radicals that contribute to lipid modification, which is essential to atheroma formation. Inflammation further fuels iron-related pathologic processes associated with plaque progression. Given iron's role in atherosclerosis development, in vivo detection techniques sensitive iron are needed for translational studies targeting iron for earlier diagnosis and treatment. Magnetic resonance imaging is uniquely able to quantify iron in human tissues noninvasively and without ionizing radiation, offering appealing for longitudinal and interventional studies. Particularly intriguing is iron's complementary biology vs. calcium, which is readily detectable by computed tomography. This review summarizes the role of iron in atherosclerosis with considerable implications for novel diagnostic and therapeutic approaches.
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384
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Ning N, Zhang L, Gao J, Zhang Y, Ren Z, Niu G, Dai Y, Wu EX, Guo Y, Yang J. Assessment of iron deposition and white matter maturation in infant brains by using enhanced T2 star weighted angiography (ESWAN): R2* versus phase values. PLoS One 2014; 9:e89888. [PMID: 24587101 PMCID: PMC3934963 DOI: 10.1371/journal.pone.0089888] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Accepted: 01/26/2014] [Indexed: 11/26/2022] Open
Abstract
Background and Purpose Iron deposition and white matter (WM) maturation are very important for brain development in infants. It has been reported that the R2* and phase values originating from the gradient-echo sequence could both reflect the iron and myelination. The aim of this study was to investigate age-related changes of R2* and phase value, and compare their performances for monitoring iron deposition and WM maturation in infant brains. Methods 56 infants were examined by enhanced T2 star weighted angiography (ESWAN) and diffusion tensor imaging in the 1.5T MRI system. The R2* and phase values were measured from the deep gray nuclei and WM. Fractional anisotropy (FA) values were measured only in the WM regions. Correlation analyses were performed to explore the relation among the two parameters (R2* and phase values) and postmenstrual age (PMA), previously published iron concentrations as well as FA values. Results We found significantly positive correlations between the R2* values and PMA in both of the gray nuclei and WM. Moreover, R2* values had a positive correlation with the iron reference concentrations in the deep gray nuclei and the FA in the WM. However, phase values only had the positive correlation with PMA and FA in the internal capsule, and no significant correlation with PMA and iron content in the deep gray nuclei. Conclusions Compared with the phase values, R2* may be a preferable method to estimate the iron deposition and WM maturation in infant brains.
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Affiliation(s)
- Ning Ning
- Radiology Department of The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
- Nuclear Medicine Department of The Second Affiliate Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
| | - Lei Zhang
- Radiology Department of The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
- Radiology Department of Baoji Center Hospital, Baoji, Shaanxi, People’s Republic of China
| | - Jie Gao
- Radiology Department of The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
| | - Yumiao Zhang
- Radiology Department of The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
| | - Zhuanqin Ren
- Radiology Department of Baoji Center Hospital, Baoji, Shaanxi, People’s Republic of China
| | - Gang Niu
- Radiology Department of The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
| | - Yongming Dai
- Radiology Department of The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
| | - Ed X. Wu
- Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, People’s Republic of China
| | - Youmin Guo
- Radiology Department of The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
| | - Jian Yang
- Radiology Department of The First Affiliated Hospital, Xi’an Jiaotong University, Xi’an, Shaanxi, People’s Republic of China
- * E-mail:
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385
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Nöth U, Volz S, Hattingen E, Deichmann R. An improved method for retrospective motion correction in quantitative T2* mapping. Neuroimage 2014; 92:106-19. [PMID: 24508652 DOI: 10.1016/j.neuroimage.2014.01.050] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 01/24/2014] [Accepted: 01/27/2014] [Indexed: 12/12/2022] Open
Abstract
A new method for motion correction of T2*-weighted data and resulting quantitative T2* maps is presented. For this method, additional data sets with a reduced number of phase encoding steps covering the k-space centre are acquired. Motion correction is based on a 3-step procedure: (1) calculation of improved input data sets with reduced artefact levels from the original data, (2) creation of a target data set free of movement artefacts on the basis of the improved input data sets, and (3) fitting of original data to the target data set, yielding an optimum combination of acquired k-space data which suppresses lines affected by movement. The method was tested on healthy subjects performing pre-trained movement. Motion correction was successful unless the same k-space line was affected by movement in all data sets acquired on a specific subject. The method was applied to patients suffering from subarachnoid haemorrhage (group 1) or tumours (group 2) with accompanying edema in the brain. Motion correction improved the interpretability of T2*-weighted patient data and resulting quantitative T2* maps considerably by allowing a clear delineation between ventricle and edema and a clear localisation of haemorrhage (group 1) or a clear delineation of tumour accompanying edema (group 2) which was not possible in data affected by movement.
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Affiliation(s)
- Ulrike Nöth
- Brain Imaging Center (BIC), Goethe University Frankfurt, Schleusenweg 2-16, D-60528 Frankfurt am Main, Germany.
| | - Steffen Volz
- Brain Imaging Center (BIC), Goethe University Frankfurt, Schleusenweg 2-16, D-60528 Frankfurt am Main, Germany
| | - Elke Hattingen
- Department of Neuroradiology, Goethe University Frankfurt, Schleusenweg 2-16, D-60528 Frankfurt am Main, Germany
| | - Ralf Deichmann
- Brain Imaging Center (BIC), Goethe University Frankfurt, Schleusenweg 2-16, D-60528 Frankfurt am Main, Germany
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386
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Carson SM, Martin MB. Effective Iron Chelation Practice for Patients With β-Thalassemia Major. Clin J Oncol Nurs 2014; 18:102-11. [DOI: 10.1188/14.cjon.102-111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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387
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Ciura VA, Romero JM. Nontraumatic Acute Intraparenchymal Hemorrhage: Algorithm for Workup and Differential Diagnosis. Semin Roentgenol 2014; 49:112-26. [DOI: 10.1053/j.ro.2013.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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388
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Automatic mapping extraction from multiecho T2-star weighted magnetic resonance images for improving morphological evaluations in human brain. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2014; 2013:202309. [PMID: 24379892 PMCID: PMC3863404 DOI: 10.1155/2013/202309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 10/23/2013] [Accepted: 10/24/2013] [Indexed: 11/17/2022]
Abstract
Mapping extraction is useful in medical image analysis. Similarity coefficient mapping (SCM) replaced signal response to time course in tissue similarity mapping with signal response to TE changes in multiecho T2-star weighted magnetic resonance imaging without contrast agent. Since different tissues are with different sensitivities to reference signals, a new algorithm is proposed by adding a sensitivity index to SCM. It generates two mappings. One measures relative signal strength (SSM) and the other depicts fluctuation magnitude (FMM). Meanwhile, the new method is adaptive to generate a proper reference signal by maximizing the sum of contrast index (CI) from SSM and FMM without manual delineation. Based on four groups of images from multiecho T2-star weighted magnetic resonance imaging, the capacity of SSM and FMM in enhancing image contrast and morphological evaluation is validated. Average contrast improvement index (CII) of SSM is 1.57, 1.38, 1.34, and 1.41. Average CII of FMM is 2.42, 2.30, 2.24, and 2.35. Visual analysis of regions of interest demonstrates that SSM and FMM show better morphological structures than original images, T2-star mapping and SCM. These extracted mappings can be further applied in information fusion, signal investigation, and tissue segmentation.
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389
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Habibollahi P, Waldron T, Heidari P, Cho HS, Alcantara D, Josephson L, Wang TC, Rustgi AK, Mahmood U. Fluorescent nanoparticle imaging allows noninvasive evaluation of immune cell modulation in esophageal dysplasia. Mol Imaging 2014; 13:1-11. [PMID: 24824854 PMCID: PMC4255710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023] Open
Abstract
Esophageal tumors provide unique challenges and opportunities for developing and testing surveillance imaging technology for different tumor microenvironment components, including assessment of immune cell modulation, with the ultimate goal of promoting early detection and response evaluation. In this context, accessibility through the lumen using a minimally invasive approach provides a means for repetitive evaluation longitudinally by combining fluorescent endoscopic imaging technology with novel fluorescent nanoparticles that are phagocytized by immune cells in the microenvironment. The agent we developed for imaging is synthesized from Feraheme (ferumoxytol), a Food and Drug Administration-approved monocrystaline dextran-coated iron oxide nanoparticle, which we conjugated to a near-infrared fluorochrome, CyAL5.5. We demonstrate a high level of uptake of the fluorescent nanoparticles by myeloid-derived suppressor cells (MDSCs) in the esophagus and spleen of L2Cre;p120ctnflox/flox mice. These mice develop esophageal dysplasia leading to squamous cell carcinoma; we have previously demonstrated that dysplastic and neoplastic esophageal lesions in these mice have an immune cell infiltration that is dominated by MDSCs. In the L2Cre;p120ctnflox/flox mice, evaluation of the spleen reveals that nearly 80% of CD45+ leukocytes that phagocytized the nanoparticle were CD11b+Gr1+ MDSCs. After dexamethasone treatment, we observed concordant decreased fluorescent signal from esophageal lesions during fluorescent endoscopy and decreased CyAL5.5-fluorescent-positive immune cell infiltration in esophageal dysplastic lesions by fluorescence-activated cell sorting analysis. Our observations suggest that this translatable technology may be used for the early detection of dysplastic changes and the serial assessment of immunomodulatory therapy and to visualize changes in MDSCs in the esophageal tumor microenvironment.
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390
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Goubran M, Rudko DA, Santyr B, Gati J, Szekeres T, Peters TM, Khan AR. In vivo normative atlas of the hippocampal subfields using multi-echo susceptibility imaging at 7 Tesla. Hum Brain Mapp 2013; 35:3588-601. [PMID: 24339427 DOI: 10.1002/hbm.22423] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 10/16/2013] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVES To generate a high-resolution atlas of the hippocampal subfields using images acquired from 7 T, multi-echo, gradient-echo MRI for the evaluation of epilepsy and neurodegenerative disorders as well as investigating R2* (apparent transverse relaxation rate) and quantitative volume magnetic susceptibility (QS) of the subfields. EXPERIMENTAL DESIGN Healthy control subjects (n=17) were scanned at 7 T using a multi-echo gradient-echo sequence and susceptibility-weighted magnitude images, R2* and QS maps were reconstructed. We defined a hippocampal subfield labeling protocol for the magnitude image produced from the average of all echoes and assessed reproducibility through volume and shape metrics. A group-wise diffeomorphic registration procedure was used to generate an average atlas of the subfields for the whole subject cohort. The quantitative MRI maps and subfield labels were then warped to the average atlas space and used to measure mean values of R2* and QS characterizing each subfield. PRINCIPAL OBSERVATIONS We were able to reliably label hippocampal subfields on the multi-echo susceptibility images. The group-averaged atlas accurately aligns these structures to produce a high-resolution depiction of the subfields, allowing assessment of both quantitative susceptibility and R2* across subjects. Our analysis of variance demonstrates that there are more apparent differences between the subfields on these quantitative maps than the normalized magnitude images. CONCLUSION We constructed a high-resolution atlas of the hippocampal subfields for use in voxel-based studies and demonstrated in vivo quantification of susceptibility and R2* in the subfields. This work is the first in vivo quantification of susceptibility values within the hippocampal subfields at 7 T.
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Affiliation(s)
- Maged Goubran
- Imaging Research Laboratories, Robarts Research Institute, Western University, London, Ontario, Canada; Biomedical Engineering, Western University, London, Ontario, Canada
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391
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Zhang C, Chaudhary N, Gemmete JJ, Elias A, Song J, Thompson BG, Galban C, Xi G, Pandey AS. Correlation of thrombus formation on 7 T MRI with histology in a rat carotid artery side wall aneurysm model. J Neurointerv Surg 2013; 6:780-4. [DOI: 10.1136/neurintsurg-2013-011032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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392
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Yang H, Zou L, Zhang S, Gong M, Zhang D, Qi Y, Zhou S, Diao X. Feasibility of MR imaging in evaluating breast cancer lymphangiogenesis using Polyethylene glycol-GoldMag nanoparticles. Clin Radiol 2013; 68:1233-40. [DOI: 10.1016/j.crad.2013.06.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 06/02/2013] [Accepted: 06/26/2013] [Indexed: 01/21/2023]
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393
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Yu S, Qiu J, Zhang J, Pan L, Xing S, Zhang L. Detection of intratumoral susceptibility signals using T2*-weighted gradient echo MRI in patients with clear cell renal cell carcinoma. PLoS One 2013; 8:e79597. [PMID: 24265780 PMCID: PMC3827137 DOI: 10.1371/journal.pone.0079597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 09/24/2013] [Indexed: 01/20/2023] Open
Abstract
Objective To retrospectively evaluate whether T2*-weighted imaging can be used to grade clear cell renal cell carcinomas (ccRCC) based on intratumoral susceptibility signals (ISSs). Materials and Methods MR imaging from 37 patients with pathologically-proven ccRCCs was evaluated. ISSs on T2*WI were classified as linear or conglomerated linear structures (type I) and dot-like or patchy foci (type II). Two radiologists assessed the likelihood of the presence of ISS, dominant structure of ISS and ratio of ISS area to tumor area. Results were analyzed by nonparametric Mann-Whitney test. Results ISSs were seen in all patients except for four patients with low-grade ccRCCs and two patients with high-grade ccRCCs. There was no significant difference of the likelihood of the presence of ISS between low- and high-grade ccRCCs. More type I ISSs and less type II ISSs were predictive of low-grade tumors, whereas more conspicuity type II ISSs correlated with higher occurrence of high-grade tumors (P<0.05). The ratio of ISS area to tumor area was also significantly higher for the high-grade group (1.27±0.79) than that for the low-grade group (0.81±0.40) (P<0.05). Conclusion ISSs on T2*-weighted gradient-echo MR images can help grade ccRCCs before operations.
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Affiliation(s)
- Shengnan Yu
- Department of Radiology, The First People's Hospital of Changzhou, Changzhou, Jiangsu, China
| | - Jianguo Qiu
- Department of Radiology, The First People's Hospital of Changzhou, Changzhou, Jiangsu, China
- * E-mail:
| | - Jinggang Zhang
- Department of Radiology, The First People's Hospital of Changzhou, Changzhou, Jiangsu, China
| | - Liang Pan
- Department of Radiology, The First People's Hospital of Changzhou, Changzhou, Jiangsu, China
| | - Shijun Xing
- Department of Radiology, The First People's Hospital of Changzhou, Changzhou, Jiangsu, China
| | - Lijun Zhang
- Department of Radiology, The First People's Hospital of Changzhou, Changzhou, Jiangsu, China
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394
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Abstract
STUDY DESIGN Experimental correlation study design to quantify features of disc health, including signal intensity and distinction between the annulus fibrosus and nucleus pulposus, with T2* magnetic resonance imaging (MRI) and correlate with the functional mechanics in corresponding motion segments. OBJECTIVE Establish the relationship between disc health assessed by quantitative T2* MRI and functional lumbar mechanics. SUMMARY OF BACKGROUND DATA Degeneration leads to altered biochemistry in the disc, affecting the mechanical competence. Clinical routine MRI sequences are not adequate in detecting early changes in degeneration and fails to correlate with pain or improve patient stratification. Quantitative T2* relaxation time mapping probes biochemical features and may offer more sensitivity in assessing disc degeneration. METHODS Cadaveric lumbar spines were imaged using quantitative T2* mapping, as well as conventional T2-weighted MRI sequences. Discs were graded by the Pfirrmann scale, and features of disc health, including signal intensity (T2* intensity area) and distinction between the annulus fibrosus and nucleus pulposus (transition zone slope), were quantified by T2*. Each motion segment was subjected to pure moment bending to determine range of motion (ROM), neutral zone (NZ), and bending stiffness. RESULTS T2* intensity area and transition zone slope were significantly correlated with flexion ROM (P = 0.015; P = 0.002), ratio of NZ/ROM (P = 0.010; P = 0.028), and stiffness (P = 0.044; P = 0.026), as well as lateral bending NZ/ROM (P = 0.005; P = 0.010) and stiffness (P = 0.022; P = 0.029). T2* intensity area was also correlated with lateral bending ROM (P = 0.023). Pfirrmann grade was only correlated with lateral bending NZ/ROM (P = 0.001) and stiffness (P = 0.007). CONCLUSION T2* mapping is a sensitive quantitative method capable of detecting changes associated with disc degeneration. Features of disc health quantified with T2* predicted altered functional mechanics of the lumbar spine better than traditional Pfirrmann grading. This new methodology and analysis technique may enhance the assessment of degeneration and enable greater patient stratification for therapeutic strategies. LEVEL OF EVIDENCE N/A.
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395
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Docampo J, Gonzalez N, Bravo F, Sarroca D, Morales C, Bruno C. Susceptibility-weighted angiography of intracranial blood products and calcifications compared to gradient echo sequence. Neuroradiol J 2013; 26:493-500. [PMID: 24199808 DOI: 10.1177/197140091302600501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 08/20/2013] [Indexed: 01/24/2023] Open
Abstract
This study evaluated the sensitivity of susceptibility-weighted angiography (SWAN) compared with gradient echo (GRE) sequence in the depiction of haemorrhagic and calcium lesions by virtue of correlation analysis between the number, area and contrast index. The study included 21 patients (15 women, 6 men; age range 18 to 80 years) in whom intracranial haemorrhage or calcifications were previously diagnosed with CT and/or MR. GRE and SWAN sequences were performed as part of a conventional Brain MR study using a 3T scanner. Pathologic findings were: cavernoma (n=8), chronic intraparenchymal haemorrhage (n=5), petechial bleeding (n=3), parenchymal calcifications (n=2), sequelae of haemorrhagic contusion focus (n=1), post-surgical glioma (n=1) and venous angioma (n=1). In eight patients, more lesions were found in the SWAN sequence than in GRE. In the measurement of the largest area, in all cases the measured area was larger in the SWAN sequence than in GRE. The SWAN sequence was reported to have shown higher contrast between the lesion and the healthy white matter than in GRE. The SWAN sequence is more sensitive than GRE in the identification of cerebral haemorrhage and calcifications. The SWAN sequence also obtained significantly larger images than with GRE, and a higher contrast difference between the lesion and the healthy parenchyma.
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Affiliation(s)
- Jorge Docampo
- Fundación Científica del Sur; Lomas de Zamora, Argentina -
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396
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Absinta M, Sati P, Gaitán MI, Maggi P, Cortese ICM, Filippi M, Reich DS. Seven-tesla phase imaging of acute multiple sclerosis lesions: a new window into the inflammatory process. Ann Neurol 2013; 74:669-78. [PMID: 23813441 PMCID: PMC3812397 DOI: 10.1002/ana.23959] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 04/15/2013] [Accepted: 05/28/2013] [Indexed: 12/27/2022]
Abstract
OBJECTIVE In multiple sclerosis (MS), accurate, in vivo characterization of dynamic inflammatory pathological changes occurring in newly forming lesions could have major implications for understanding disease pathogenesis and mechanisms of tissue destruction. Here, we investigated the potential of ultrahigh-field magnetic resonance imaging (MRI; 7T), particularly phase imaging combined with dynamic contrast enhancement, to provide new insights in acute MS lesions. METHODS Sixteen active MS patients were studied at 7T. Noncontrast, high-resolution T2* magnitude and phase scans, T1 scans before/after gadolinium contrast injection, and dynamic contrast-enhanced (DCE) T1 scans were acquired. T2*/phase features and DCE pattern were determined for acute and chronic lesions. When possible, 1-year follow-up 7T MRI was performed. RESULTS Of 49 contrast-enhancing lesions, 44 could be analyzed. Centrifugal DCE lesions appeared isointense or hypointense on phase images, whereas centripetal DCE lesions showed thin, hypointense phase rims that clearly colocalized with the initial site of contrast enhancement. This pattern generally disappeared once enhancement resolved. Conversely, in 43 chronic lesions also selected for the presence of hypointense phase rims, the findings were stable over time, and the rims were typically thicker and darker. These considerations suggest different underlying pathological processes in the 2 lesion types. INTERPRETATION Ultrahigh-field MRI and, especially, phase contrast, are highly sensitive to tissue changes in acute MS lesions, which differ from the patterns seen in chronic lesions. In acute lesions, the hypointense phase rim reflects the expanding inflammatory edge and may directly correspond to inflammatory byproducts and sequelae of blood-brain barrier opening.
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Affiliation(s)
- Martina Absinta
- Translational Neuroradiology Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD; Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
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397
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Pablico-Lansigan MH, Hickling WJ, Japp EA, Rodriguez OC, Ghosh A, Albanese C, Nishida M, Van Keuren E, Fricke S, Dollahon N, Stoll SL. Magnetic nanobeads as potential contrast agents for magnetic resonance imaging. ACS NANO 2013; 7:9040-8. [PMID: 24047405 DOI: 10.1021/nn403647t] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Metal-oxo clusters have been used as building blocks to form hybrid nanomaterials and evaluated as potential MRI contrast agents. We have synthesized a biocompatible copolymer based on a water stable, nontoxic, mixed-metal-oxo cluster, Mn8Fe4O12(L)16(H2O)4, where L is acetate or vinyl benzoic acid, and styrene. The cluster alone was screened by NMR for relaxivity and was found to be a promising T2 contrast agent, with r1 = 2.3 mM(-1) s(-1) and r2 = 29.5 mM(-1) s(-1). Initial cell studies on two human prostate cancer cell lines, DU-145 and LNCap, reveal that the cluster has low cytotoxicity and may be potentially used in vivo. The metal-oxo cluster Mn8Fe4(VBA)16 (VBA = vinyl benzoic acid) can be copolymerized with styrene under miniemulsion conditions. Miniemulsion allows for the formation of nanometer-sized paramagnetic beads (~80 nm diameter), which were also evaluated as a contrast agent for MRI. These highly monodispersed, hybrid nanoparticles have enhanced properties, with the option for surface functionalization, making them a promising tool for biomedicine. Interestingly, both relaxivity measurements and MRI studies show that embedding the Mn8Fe4 core within a polymer matrix decreases r2 effects with little effect on r1, resulting in a positive T1 contrast enhancement.
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Affiliation(s)
- Michele H Pablico-Lansigan
- Department of Chemistry, Georgetown University , 37th and O Streets NW, Washington, D.C. 20057, United States
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398
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A comparison of CT/CT angiography and MRI/MR angiography for imaging of vertebrobasilar dolichoectasia. Clin Neuroradiol 2013; 24:347-53. [PMID: 24132554 DOI: 10.1007/s00062-013-0261-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Accepted: 09/24/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE Vertebrobasilar dolichoectasia (VBD) is a rare dilatative arteriopathy predominantly affecting the basilar artery (BA) and vertebral arteries. Until today, the value of computed tomography (CT)/CT angiography (CTA) compared with magnetic resonance imaging (MRI)/time-of-flight MR angiography (TOF-MRA) has not been studied systematically. METHODS We (1) compare CTA and TOF-MRA according to the established criteria (diameter at the mid-pons level, height, and lateral position), (2) explore the value of further CTA- and TOF-MRA-derived measures (maximum transverse diameter and length), as well as (3) explore the value of further non-contrast-enhanced MRI sequences such as T1, fluid-attenuated inversion recovery, and T2* for a detailed characterization of VBD in a series of 18 patients. RESULTS Comparison of CTA and TOF-MRA revealed very good consistency of the measured diameter (Pearson's r = 0.994, p = 0.01) and the noted height of the BA (Kendall's tau = 1.0, p = 0.001). The same held true for the maximum transverse diameter (Pearson's r = 0.988, p = 0.01) and length of the BA (Pearson's r = 0.986, p = 0.01). In contrast to this, there was a lower agreement concerning the lateral position (Kendall's tau = 0.866, p = 0.01). In comparison with the diameter at the mid-pons level, the maximum transverse diameter was significantly larger (p = 0.002). Luminal thrombus was detected equally well by CTA and TOF-MRA. CT was useful to detect small circumscribed calcifications, whereas MRI was advantageous to demonstrate perifocal brainstem edema. CONCLUSIONS We could demonstrate a substantial comparability of CT/CTA and MRI/TOF-MRA in the diagnosis of VBD. The maximum transverse diameter and length may be useful when an endovascular treatment is considered. Taking into account the different informative value of both techniques, it may be worth to perform both imaging procedures.
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399
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Reginold W, Lang AE, Marras C, Heyn C, Alharbi M, Mikulis DJ. Longitudinal quantitative MRI in multiple system atrophy and progressive supranuclear palsy. Parkinsonism Relat Disord 2013; 20:222-5. [PMID: 24239142 DOI: 10.1016/j.parkreldis.2013.10.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 09/20/2013] [Accepted: 10/01/2013] [Indexed: 12/15/2022]
Abstract
OBJECTIVE MRI has been used in parkinsonism to assess atrophy, tissue water diffusivity, and mineral deposition but usually at a single time-point. However, multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) are progressive diseases. This study assessed the value of longitudinal MRI in characterizing the time course of the degenerative process. METHODS Two serial MRIs (mean 23 months apart) were retrospectively analyzed in 12 MSA, 6 PSP, and 18 age and sex matched controls. Assessment included selected cross-sectional areas, regional apparent diffusion coefficient (ADC) and gradient echo (GRE) intensity ratios of the lateral ventricles, caudate, putamen, middle cerebellar peduncle, pons and midbrain. RESULTS On follow-up imaging, there was a larger ADC increase in the putamen in PSP over time compared to controls (p = 0.02). In MSA there was greater volume loss in the pons over time compared to controls (p = 0.002). In MSA the changes in middle cerebellar peduncle ADC were correlated with motor symptom severity according to the Unified Parkinson's Disease Rating Scale Part III (p = 0.005). CONCLUSIONS Evidence of progressive neurodegeneration can be observed on MRI in MSA and PSP within two years consisting of increasing putaminal ADC in PSP and pontine atrophy in MSA.
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Affiliation(s)
- William Reginold
- Morton and Gloria Shulman Movement Disorders Centre and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Canada; Department of Medical Imaging, Toronto Western Hospital, the Joint Department of Medical Imaging, and The University of Toronto, Canada.
| | - Anthony E Lang
- Morton and Gloria Shulman Movement Disorders Centre and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Canada; Department of Medicine (Neurology), University of Toronto, Canada.
| | - Connie Marras
- Morton and Gloria Shulman Movement Disorders Centre and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Canada; Department of Medicine (Neurology), University of Toronto, Canada.
| | - Chris Heyn
- Department of Medical Imaging, Toronto Western Hospital, the Joint Department of Medical Imaging, and The University of Toronto, Canada.
| | - Mohammed Alharbi
- Department of Medical Imaging, Toronto Western Hospital, the Joint Department of Medical Imaging, and The University of Toronto, Canada.
| | - David J Mikulis
- Department of Medical Imaging, Toronto Western Hospital, the Joint Department of Medical Imaging, and The University of Toronto, Canada.
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400
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Fussell D, Young RJ. Role of MRI perfusion in improving the treatment of brain tumors. ACTA ACUST UNITED AC 2013. [DOI: 10.2217/iim.13.50] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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