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Jiang Z, Sun W, Xu D, Mei H, Yuan J, Song X, Ma C, Xu H. The feasibility of half-dose contrast-enhanced scanning of brain tumours at 5.0 T: a preliminary study. BMC Med Imaging 2024; 24:88. [PMID: 38615005 PMCID: PMC11016225 DOI: 10.1186/s12880-024-01270-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 04/05/2024] [Indexed: 04/15/2024] Open
Abstract
PURPOSE This study investigated and compared the effects of Gd enhancement on brain tumours with a half-dose of contrast medium at 5.0 T and with a full dose at 3.0 T. METHODS Twelve subjects diagnosed with brain tumours were included in this study and underwent MRI after contrast agent injection at 3.0 T (full dose) or 5.0 T (half dose) with a 3D T1-weighted gradient echo sequence. The postcontrast images were compared by two independent neuroradiologists in terms of the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and subjective image quality score on a ten-point Likert scale. Quantitative indices and subjective quality ratings were compared with paired Student's t tests, and interreader agreement was assessed with the intraclass correlation coefficient (ICC). RESULTS A total of 16 enhanced tumour lesions were detected. The SNR was significantly greater at 5.0 T than at 3.0 T in grey matter, white matter and enhanced lesions (p < 0.001). The CNR was also significantly greater at 5.0 T than at 3.0 T for grey matter/tumour lesions, white matter/tumour lesions, and grey matter/white matter (p < 0.001). Subjective evaluation revealed that the internal structure and outline of the tumour lesions were more clearly displayed with a half-dose at 5.0 T (Likert scale 8.1 ± 0.3 at 3.0 T, 8.9 ± 0.3 at 5.0 T, p < 0.001), and the effects of enhancement in the lesions were comparable to those with a full dose at 3.0 T (7.8 ± 0.3 at 3.0 T, 8.7 ± 0.4 at 5.0 T, p < 0.001). All subjective scores were good to excellent at both 5.0 T and 3.0 T. CONCLUSION Both quantitative and subjective evaluation parameters suggested that half-dose enhanced scanning via 5.0 T MRI might be feasible for meeting clinical diagnostic requirements, as the image quality remains optimal. Enhanced scanning at 5.0 T with a half-dose of contrast agents might benefit patients with conditions that require less intravenous contrast agent, such as renal dysfunction.
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Affiliation(s)
- Zhiyong Jiang
- Department of Radiology, Zhongnan Hospital of Wuhan University, Wuhan, China
- Medical Imaging Department, Shenzhen Ban'an Traditional Chinese Medicine Hospital Group, Shenzhen, China
| | - Wenbo Sun
- Department of Radiology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Dan Xu
- Department of Nuclear Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Hao Mei
- Department of Radiology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | | | - Xiaopeng Song
- United Imaging Healthcare, Shanghai, China
- Wuhan Zhongke Industrial Research Institute, Wuhan, Hubei, China
| | - Chao Ma
- Department of Neurosurgery, Zhongnan Hospital, Wuhan, China.
| | - Haibo Xu
- Department of Radiology, Zhongnan Hospital of Wuhan University, Wuhan, China.
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Golden RK, Sutkus LT, Donovan SM, Dilger RN. Dietary supplementation of 3'-sialyllactose or 6'-sialyllactose elicits minimal influence on cognitive and brain development in growing pigs. Front Behav Neurosci 2024; 17:1337897. [PMID: 38268796 PMCID: PMC10806065 DOI: 10.3389/fnbeh.2023.1337897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 12/21/2023] [Indexed: 01/26/2024] Open
Abstract
Sialylated human milk oligosaccharides (HMO), such as 3'-sialyllactose (3'-SL) and 6'-sialyllactose (6'-SL), are abundant throughout lactation and at much higher concentrations than are present in bovine milk or infant formulas. Previous studies have suggested that sialylated HMO may have neurocognitive benefits in early life. Recent research has focused on infant formula supplementation with key nutrients and bioactives to narrow the developmental gap between formula-fed and breastfed infants. Herein, we investigated the impact of supplemental 3'-SL or 6'-SL on cognitive and brain development at two time-points [postnatal days (PND) 33 and 61]. Two-day-old piglets (N = 75) were randomly assigned to commercial milk replacer ad libitum without or with 3'-SL or 6'-SL (added in a powdered form at a rate of 0.2673% on an as-is weight basis). Cognitive development was assessed via novel object recognition and results were not significant at both time-points (p > 0.05). Magnetic resonance imaging was used to assess structural brain development. Results varied between scan type, diet, and time-point. A main effect of diet was observed for absolute volume of white matter and 9 other regions of interest (ROI), as well as for relative volume of the pons on PND 30 (p < 0.05). Similar effects were observed on PND 58. Diffusion tensor imaging indicated minimal differences on PND 30 (p > 0.05). However, several dietary differences across the diffusion outcomes were observed on PND 58 (p < 0.05) indicating dietary impacts on brain microstructure. Minimal dietary differences were observed from myelin water fraction imaging at either time-point. Overall, sialyllactose supplementation had no effects on learning and memory as assessed by novel object recognition, but may influence temporally-dependent aspects of brain development.
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Affiliation(s)
- Rebecca K. Golden
- Neuroscience Program, University of Illinois, Urbana, IL, United States
| | - Loretta T. Sutkus
- Neuroscience Program, University of Illinois, Urbana, IL, United States
| | - Sharon M. Donovan
- Department of Food Science and Human Nutrition, University of Illinois, Urbana, IL, United States
- Division of Nutritional Sciences, University of Illinois, Urbana, IL, United States
| | - Ryan N. Dilger
- Neuroscience Program, University of Illinois, Urbana, IL, United States
- Division of Nutritional Sciences, University of Illinois, Urbana, IL, United States
- Department of Animal Sciences, University of Illinois, Urbana, IL, United States
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Antoine LH, Tanner JJ, Mickle AM, Gonzalez CE, Kusko DA, Watts KA, Rumble DD, Buchanan TL, Sims AM, Staud R, Lai S, Deshpande H, Phillips B, Buford TW, Aroke EN, Redden DT, Fillingim RB, Goodin BR, Sibille KT. Greater socioenvironmental risk factors and higher chronic pain stage are associated with thinner bilateral temporal lobes. Brain Behav 2023; 13:e3330. [PMID: 37984835 PMCID: PMC10726852 DOI: 10.1002/brb3.3330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 10/31/2023] [Accepted: 11/02/2023] [Indexed: 11/22/2023] Open
Abstract
INTRODUCTION Previous research indicates ethnic/race group differences in pain and neurodegenerative diseases. Accounting for socioenvironmental factors reduces ethnic/race group differences in clinical and experimental pain. In the current study sample, we previously reported that in individuals with knee pain, ethnic/race group differences were observed in bilateral temporal lobe thickness, areas of the brain associated with risk for Alzheimer's disease, and related dementias. The purpose of the study was to determine if socioenvironmental factors reduce or account for previously observed ethnic/race group differences and explore if a combined effect of socioenvironmental risk and chronic pain severity on temporal lobe cortices is evident. METHODS Consistent with the prior study, the sample was comprised of 147 adults (95 women, 52 men), 45-85 years of age, who self-identified as non-Hispanic Black (n = 72) and non-Hispanic White (n = 75), with knee pain with/at risk for osteoarthritis. Measures included demographics, health history, pain questionnaires, cognitive screening, body mass index, individual- and community-level socioenvironmental factors (education, income, household size, marital and insurance status, and area deprivation index), and brain imaging. We computed a summative socioenvironmental risk index. RESULTS Regression analyses showed that with the inclusion of socioenvironmental factors, the model was significant (p < .001), and sociodemographic (ethnic/race) group differences were not significant (p = .118). Additionally, findings revealed an additive stress load pattern indicating thinner temporal lobe cortices with greater socioenvironmental risk and chronic pain severity (p = .048). IMPLICATIONS Although individual socioenvironmental factors were not independent predictors, when collectively combined in models, ethnic/race group differences in bilateral temporal lobe structures were not replicated. Further, combined socioenvironmental risk factors and higher chronic pain severity were associated with thinner bilateral temporal lobes.
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Affiliation(s)
- Lisa H. Antoine
- Department of PsychologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Jared J. Tanner
- Department of Clinical and Health PsychologyUniversity of FloridaGainesvilleFloridaUSA
| | - Angela M. Mickle
- Pain Research & Intervention Center of ExcellenceUniversity of FloridaGainesvilleFloridaUSA
- Department of Physical Medicine & RehabilitationUniversity of FloridaGainesvilleFloridaUSA
| | - Cesar E. Gonzalez
- Department of PsychologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Daniel A. Kusko
- Department of PsychologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Kristen Allen Watts
- Heersink School of MedicineUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Deanna D. Rumble
- Department of Psychology and CounselingUniversity of Central ArkansasConwayArkansasUSA
| | - Taylor L. Buchanan
- Center for Exercise MedicineUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Andrew M. Sims
- Department of BiostatisticsUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Roland Staud
- Department of MedicineUniversity of FloridaGainesvilleFloridaUSA
| | - Song Lai
- Department of Radiation OncologyUniversity of FloridaGainesvilleFloridaUSA
| | | | - Brandis Phillips
- Department of Accounting & FinanceNorth Carolina A&T State UniversityGreensboroNorth CarolinaUSA
| | - Thomas W. Buford
- Department of Medicine − Division of Gerontology, Geriatrics, and Palliative CareUniversity of Alabama at BirminghamBirminghamAlabamaUSA
- Birmingham/Atlanta Geriatric Research, Education, and Clinical CenterBirmingham VA Medical CenterBirminghamAlabamaUSA
| | - Edwin N. Aroke
- School of NursingUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - David T. Redden
- Department of BiostatisticsUniversity of Alabama at BirminghamBirminghamAlabamaUSA
| | - Roger B. Fillingim
- Pain Research & Intervention Center of ExcellenceUniversity of FloridaGainesvilleFloridaUSA
- Department of Community of Dentistry and Behavioral SciencesUniversity of FloridaGainesvilleFloridaUSA
| | - Burel R. Goodin
- Department of PsychologyUniversity of Alabama at BirminghamBirminghamAlabamaUSA
- Department of AnesthesiologyWashington University, Washington University Pain CenterSt. LouisMissouriUSA
| | - Kimberly T. Sibille
- Pain Research & Intervention Center of ExcellenceUniversity of FloridaGainesvilleFloridaUSA
- Department of Physical Medicine & RehabilitationUniversity of FloridaGainesvilleFloridaUSA
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Kang Y, Chen Y, Fang J, Huang Y, Wang H, Gong Z, Zhan S, Tan W. Performance of a Flexible 12-Channel Head Coil in Comparison to Commercial 16- And 24-Channel Rigid Head Coils. Magn Reson Med Sci 2021; 21:623-631. [PMID: 34544923 PMCID: PMC9618927 DOI: 10.2463/mrms.mp.2021-0084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Purpose: To compare the performance of a 12-channel flexible head coil (HFC12) with commercial 16-channel (HRC16) and 24-channel (HRC24) rigid coils. Methods: The phantom study was performed on a 1.5 T MR scanner with HFC12, HRC16, and HRC24. The SNR and noise correlation matrix of T1WI, T2WI, and diffusion weighted imaging (DWI) were measured. The SNR profiles were created according to the SNR. In addition, 1/g-factors were calculated in different acceleration directions. In the in vivo study, T1WI, T2WI, and DWI were performed in one healthy volunteer with three different coils. The SNR and noise correlation matrix were measured. Results: In the phantom study and in vivo study, the SNR of HFC12 in the transverse, sagittal, and coronal planes was the highest, followed by HRC24, and that of HRC16 was the lowest. The SNR profiles showed that the SNR at the edge of HFC12 was the highest. The mean value of the noise correlation matrix of HFC12 was the highest. The 1/g-factor results showed that HFC12 obtained the best acceleration ability in the head–foot acceleration direction when the reduction factor was set to two. The SNR of HFC12 in most cortices was significantly higher than that of HRC16 and HRC24, except in the occipital cortex. The SNR of HRC24 in the occipital cortex was higher than that of HFC12. Conclusion: The SNR of HFC12 in T1WI, T2WI, and DWI was better than that of the HRC24 and HFC16. The SNR of HFC12 in the cortex was significantly higher than that of the commercial rigid head coil, except in the occipital cortex.
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Affiliation(s)
- YingJie Kang
- Department of Radiology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine
| | - YiLei Chen
- Department of Radiology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine
| | - JieMing Fang
- Department of Diagnostic Radiology, City of Hope Medical Center
| | - YanWen Huang
- Department of Radiology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine
| | - Hui Wang
- Department of Radiology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine
| | - ZhiGang Gong
- Department of Radiology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine
| | - SongHua Zhan
- Department of Radiology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine
| | - WenLi Tan
- Department of Radiology, Shuguang Hospital Affiliated with Shanghai University of Traditional Chinese Medicine
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Comparison of treatment position with mask immobilization and standard diagnostic setup in intracranial MRI radiotherapy simulation. Strahlenther Onkol 2021; 197:614-621. [PMID: 33881558 DOI: 10.1007/s00066-021-01776-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 03/23/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE This study aims to compare the quality of images resulting from magnetic resonance imaging of patients who underwent intracranial MRI simulation using two different setups (treatment position with mask immobilization and standard diagnostic setup). Due to a larger number of channels and lack of mask immobilization in the standard diagnostic setup, we would like to evaluate whether this is an appropriate technique for MRI treatment planning. METHODS In total, 70 patients who underwent MR imaging of the brain at 1.5T were included in the study (48 for 6‑channel flex coil, 22 for 24-channel HNU face bill coil). Contrast-enhanced 3D T1w and T2 FLAIR images were acquired. Images were subjectively compared for artifact appearance and general image quality by three radiographers. Objective comparison of contrast rate, contrast-to-noise ratio, and signal-to-noise ratio was also performed. RESULTS FLAIR and contrast-enhanced 3D T1w images showed various artifacts, such as susceptibility and movement artifacts. There were no statistically significant differences regarding the evaluation of movement artifacts between two coils and two different immobilization methods. There were also no statistically significant differences (p > 0.05) between the 6‑channel flex coil and 24-channel HNU face bill coil regarding qualitative general image quality and objective measures. CONCLUSION There were no statistically significant differences between the occurrence of movement artifacts, overall image quality, and objective image quality in treatment position with mask immobilization and standard diagnostic setup. Based on this result, we can conclude that a standard diagnostic setup is also applicable in intracranial MRI treatment planning with no loss to image quality. Registration of the imaging plans was not performed in this study; therefore, it might still be necessary to perform measurements of tumor delineation matching and geometrical accuracy acceptance in our institution.
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Nakai R, Azuma T, Nakaso Y, Sawa S, Demura T. Development of a dynamic imaging method for gravitropism in pea sprouts using clinical magnetic resonance imaging system. PLANT BIOTECHNOLOGY (TOKYO, JAPAN) 2020; 37:437-442. [PMID: 33850431 PMCID: PMC8034701 DOI: 10.5511/plantbiotechnology.20.1020a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 10/20/2020] [Indexed: 05/17/2023]
Abstract
Although magnetic resonance imaging (MRI) is a useful technique, only a few studies have investigated the dynamic behavior of small subjects using MRI owing to constraints such as experimental space and signal amount. In this study, to acquire high-resolution continuous three-dimensional gravitropism data of pea (Pisum sativum) sprouts, we developed a small-bore MRI signal receiver coil that can be used in a clinical MRI and adjusted the imaging sequence. It was expected that such an arrangement would improve signal sensitivity and improve the signal-to-noise ratio (SNR) of the acquired image. All MRI experiments were performed using a 3.0-T clinical MRI scanner. An SNR comparison using an agarose gel phantom to confirm the improved performance of the small-bore receiver coil and an imaging experiment of pea sprouts exhibiting gravitropism were performed. The SNRs of the images acquired with a standard 32-channel head coil and the new small-bore receiver coil were 5.23±0.90 and 57.75±12.53, respectively. The SNR of the images recorded using the new coil was approximately 11-fold higher than that of the standard coil. In addition, when the accuracy of MR imaging that captures the movement of pea sprout was verified, the difference in position information from the optical image was found to be small and could be used for measurements. These results of this study enable the application of a clinical MRI system for dynamic plant MRI. We believe that this study is a significant first step in the development of plant MRI technique.
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Affiliation(s)
- Ryusuke Nakai
- Kokoro Research Center, Kyoto University, 46 Shimoadachi-cho, Yoshida Sakyo-ku, Kyoto 606-8501, Japan
| | - Takashi Azuma
- Graduate School of Medicine, Kyoto University, 54 Shogoinkawahara-cho, Sakyo-ku, Kyoto 606-8397, Japan
| | - Yosuke Nakaso
- Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Shinichiro Sawa
- Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-0862, Japan
| | - Taku Demura
- Graduate School of Science and Technology, Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara 630-0192, Japan
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Machado-Rivas F, Jaimes C, Kirsch JE, Gee MS. Image-quality optimization and artifact reduction in fetal magnetic resonance imaging. Pediatr Radiol 2020; 50:1830-1838. [PMID: 33252752 DOI: 10.1007/s00247-020-04672-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 03/09/2020] [Accepted: 03/31/2020] [Indexed: 11/28/2022]
Abstract
Fetal MRI allows for earlier and better detection of complex congenital anomalies. However, its diagnostic utility is often limited by technical barriers that introduce artifacts and reduce image quality. The main determinants of fetal MR image quality are speed of acquisition, spatial resolution and signal-to-noise ratio (SNR). Imaging optimization is a challenge because a change to improve one scan parameter often leads to worsening of another. Moreover, the recent introduction of fetal MRI on 3-tesla (T) scanners to achieve better SNR can amplify some technical issues. Motion, banding artifacts and aliasing artifacts impact the quality of fetal acquisitions at any field strength. High specific absorption rate (SAR) and artifacts from inhomogeneities in the radiofrequency field are important limitations of high-field-strength imaging. We discuss technical barriers that impact image quality and are important limitations to prenatal MRI diagnosis, and propose solutions to improve image quality and reduce artifacts.
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Affiliation(s)
- Fedel Machado-Rivas
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St., Boston, MA, 02114, USA.,Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Camilo Jaimes
- Department of Radiology, Harvard Medical School, Boston, MA, USA.,Department of Radiology, Boston Children's Hospital, Boston, MA, USA
| | - John E Kirsch
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St., Boston, MA, 02114, USA.,Department of Radiology, Harvard Medical School, Boston, MA, USA
| | - Michael S Gee
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St., Boston, MA, 02114, USA. .,Department of Radiology, Harvard Medical School, Boston, MA, USA.
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Kim B, Chang Y, Choi HJ, Park KS, Yang JU, Kim E, Park SH. Development of a Stereotactic Radiosurgery Frame Adapter for a Multichannel MRI Coil. Stereotact Funct Neurosurg 2020; 99:159-166. [PMID: 33242875 DOI: 10.1159/000510476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/27/2020] [Indexed: 11/19/2022]
Abstract
BACKGROUND The usage of multichannel brain MRI coils, which have several advantages over single-channel brain coils used for stereotactic radiosurgery (SRS), requires a frame adapter device to fit the frames inside the multichannel brain coils. However, such a frame adapter has not been developed until now. OBJECTIVE to develop an SRS frame adapter for multichannel MRI coils and verify the geometrical accuracy and signal-to-noise ratio (SNR) of the MR images obtained using multichannel MRI coils. METHODS We fabricated an SRS frame adapter for a 48-channel MRI coil using a three-dimensional (3D) printer. Furthermore, we obtained phantom and human-brain MR images with a 3.0 Tesla MRI scanner using multi- and single-channel coils. Computed tomography (CT) phantom images were also obtained as reference. We compared the coordinate errors of the multi- and single-channel coils to evaluate the geometrical accuracy. Two neurosurgeons measured the coordinates. In addition, we compared the SNR differences between multi- and single-channel coils using the T1- and T2-weighted brain images. RESULTS For the CT coordinate measurements, the correlation coefficient r = 1 and p < 0.001 with respect to the 3 axes (Δx, Δy, and Δz) and 3D errors (Δr) showed no interpersonal differences between the 2 neurosurgeons. The results obtained using the T1-weighted images showed that a multichannel coil had smaller coordinate errors in Δx, Δy, Δz, and Δr than that observed in case of a single-channel coil (p < 0.001). In case of the SNR measurements, most of the brain areas showed higher SNRs when using a multichannel coil compared with that observed when using a single-channel coil in the T1- and T2-weighted images. CONCLUSION Compared with single-channel coils, the use of multichannel MRI coils with a newly developed frame adapter is expected to ensure successful SRS treatments with improved geometrical accuracy and SNR.
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Affiliation(s)
- Byungmok Kim
- Department of Medical & Biological Engineering, Kyungpook National University, Daegu, Republic of Korea.,Department of Neurosurgery, Kyungpook National University Hospital, Daegu, Republic of Korea
| | - Yongmin Chang
- Department of Molecular Medicine, Kyungpook National University School of Medicine, Daegu, Republic of Korea.,Department of Radiology, Kyungpook National University Hospital, Daegu, Republic of Korea
| | - Hea Jung Choi
- Department of Medical & Biological Engineering, Kyungpook National University, Daegu, Republic of Korea
| | - Ki-Su Park
- Department of Neurosurgery, Kyungpook National University Hospital, Daegu, Republic of Korea.,Department of Neurosurgery, Kyungpook National University School of Medicine, Daegu, Republic of Korea
| | - Ji-Ung Yang
- Department of Medical & Biological Engineering, Kyungpook National University, Daegu, Republic of Korea
| | - Eunji Kim
- Department of Medical & Biological Engineering, Kyungpook National University, Daegu, Republic of Korea
| | - Seong-Hyun Park
- Department of Neurosurgery, Kyungpook National University Hospital, Daegu, Republic of Korea, .,Department of Neurosurgery, Kyungpook National University School of Medicine, Daegu, Republic of Korea,
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Kashani N, Khan N, Ospel JM, Wei XC. MRI Head Coil Malfunction Producing Artifacts Mimicking Malformation of Cortical Development in Pediatric Epilepsy Work-Up. AJNR Am J Neuroradiol 2020; 41:1538-1540. [PMID: 32616579 DOI: 10.3174/ajnr.a6639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 05/12/2020] [Indexed: 11/07/2022]
Abstract
We recently observed a type of MR imaging artifact that consistently mimics an abnormal appearance of the cerebral cortex, leading to initial misinterpretation and repeat scans. The artifact is caused by malfunction of part of the multichannel phased array head coil and is manifested by irregularity of cortical surface and gray-white matter junctions. The presence of such an artifact can be confirmed by assessing the background noise of the MR images and checking the coil element status on the MR imaging operator console.
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Affiliation(s)
- N Kashani
- From the Department of Radiology (N. Kashani. N. Khan, J.M.O.), University of Calgary, Calgary, Alberta, Canada
| | - N Khan
- From the Department of Radiology (N. Kashani. N. Khan, J.M.O.), University of Calgary, Calgary, Alberta, Canada
| | - J M Ospel
- From the Department of Radiology (N. Kashani. N. Khan, J.M.O.), University of Calgary, Calgary, Alberta, Canada
| | - X-C Wei
- Diagnostic Imaging (X.-C.W.), Alberta Children's Hospital, Calgary, Alberta, Canada.
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10
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Nagtegaal SH, van Lier AL, den Boer AA, Kramer MC, Fanetti G, Eppinga WS, Philippens ME, Verhoeff JJ, Seravalli E. Does an immobilization mask have added value during planning magnetic resonance imaging for stereotactic radiotherapy of brain tumours? Phys Imaging Radiat Oncol 2020; 13:7-13. [PMID: 33458301 PMCID: PMC7807597 DOI: 10.1016/j.phro.2020.02.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 02/13/2020] [Accepted: 02/21/2020] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE When using an immobilization mask, a magnetic resonance imaging (MRI) head receive coil cannot be used and patients may experience discomfort during the examination. We therefore wish to assess the added value of an immobilization mask during all MRI scans intended for cranial stereotactic radiotherapy (SRT) planning. MATERIALS AND METHODS An MRI was acquired with and without a thermoplastic immobilization mask in ten patients eligible for SRT. A planning computed tomography (CT) scan was also made, to which the two MRIs were independently registered. Additionally, the MRI without immobilization was registered to the MRI in mask. On each sequence, gross tumour volume (GTV), the right eye, brain stem and chiasm were delineated. The absolute differences in centre-of-gravity coordinates and Dice coefficients of the volumes of the delineated structures between the two MRIs were compared. RESULTS Differences in GTV volume between the two MRIs were low, with median Dice coefficients between 0.88 and 0.91. Similarly, the median absolute differences in centre-of-gravity coordinates between the GTVs, organs at risk and landmarks delineated on the two MRIs were within 0.5 mm. The 95% confidence intervals of the median absolute differences in the three GTV coordinates was within 1 mm, which corresponds to the target volume safety margin used to account for possible errors during the SRT treatment chain. CONCLUSIONS The effect of scanning a patient without the immobilization mask falls within acceptable bounds of error for the geometrical accuracy of the SRT treatment chain. Consequently, placing the head in treatment position during all MRI scans for patients undergoing radiotherapy of brain metastasis is deemed unnecessary.
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Affiliation(s)
| | | | - Anne A. den Boer
- UMC Utrecht, Department of Radiation Oncology, Utrecht, The Netherlands
| | | | - Giuseppe Fanetti
- Centro di Riferimento Oncologico di Aviano (CRO) IRCCS, Aviano, Italy
| | | | | | | | - Enrica Seravalli
- UMC Utrecht, Department of Radiation Oncology, Utrecht, The Netherlands
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Li Y, Chen Q, Wei Z, Zhang L, Tie C, Zhu Y, Jia S, Xia J, Liang D, He Q, Zhang X, Liu X, Zhang B, Zheng H. One-Stop MR Neurovascular Vessel Wall Imaging With a 48-Channel Coil System at 3 T. IEEE Trans Biomed Eng 2019; 67:2317-2327. [PMID: 31831406 DOI: 10.1109/tbme.2019.2959030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE The purpose of this article was to build a radio frequency (RF) coil system to achieve high vessel wall image quality with coverage extending from the aortic arch to the intracranial vessels. METHODS A 48-channel coil system was built and characterized at a 3 tesla (T) Magnetic Resonance Imaging (MRI) scanner (uMR 790, Shanghai United Imaging Healthcare, Shanghai, China). The coil's performance was compared with a commercially available 36-channel coil system. By human studies, signal-to-noise ratio (SNR) units were evaluated and g-factors were calculated in the transverse planes of the brain and neck regions. RESULTS The SNR was increased by at least 28% in the brain region and up to fourfold in the neck region. The average g-factor with the acceleration factor, R = 3, was lowered by 21% in the transverse plane of the neck region. Intracranial and carotid arterial wall images with an isotropic spatial resolution of 0.63 mm were acquired within 7.7 minutes and thoracic aorta wall images with an isotropic spatial resolution of 1.1 mm were acquired within 2.7 minutes with the 48-channel coil system. The vessel wall can be more clearly visualized with the 48-channel coil system compared with the 36-channel coil system. CONCLUSION A 48-channel coil system was developed and demonstrated superior performance for vessel wall imaging at the intracranial and cervical carotid arteries compared with a commercial 36-channel coil. SIGNIFICANCE The 48-channel coil system is potentially useful for clinical diagnostics, especially when attempting to diagnose ischemic stroke.
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Stieb S, Elgohari B, Fuller CD. Repetitive MRI of organs at risk in head and neck cancer patients undergoing radiotherapy. Clin Transl Radiat Oncol 2019; 18:131-139. [PMID: 31341989 PMCID: PMC6630152 DOI: 10.1016/j.ctro.2019.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 04/16/2019] [Accepted: 04/16/2019] [Indexed: 02/07/2023] Open
Abstract
First review on MRI changes in head and neck organs at risk during radiotherapy. Focus on dynamics in salivary gland, muscle and bone in the head and neck region. Pointing out the limitations in implementing MRI in guiding radiation therapy.
With emerging technical advances like real-time MR imaging during radiotherapy (RT) with an integrated MR linear accelerator, it will soon be possible to analyze changes in the organs at risk (OARs) during radiotherapy without additional effort for the patients. Until then, patients have to undergo additional MR imaging and often without the same immobilization devices as used for radiotherapy. Consequently, studies with repetitive MRI during the course of radiotherapy are rare, with low patient numbers and with the challenge of registration between the different MR sequences and the varying imaging time points. This review focuses on studies with at least two MRIs, one before and another either during or post-RT, in order to report on RT-induced changes in normal tissues and their correlation with toxicity. We therefore included clinical studies published in English until March 2019, with repetitive MRI of OARs in head and neck cancer patients receiving external beam radiotherapy. OARs analyzed were salivary glands, musculoskeletal structures and bones. MR sequences used included T1, T2, dynamic contrast enhanced (DCE) imaging, diffusion-weighted imaging (DWI), DIXON and MR sialography.
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Affiliation(s)
- Sonja Stieb
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Baher Elgohari
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.,Department of Clinical Oncology and Nuclear Medicine, Mansoura University, Mansoura, Egypt
| | - Clifton David Fuller
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Okazaki T, Niwa T, Suzuki K, Shibukawa S, Imai Y. Age related signal changes of the pituitary stalk on thin-slice magnetic resonance imaging in infants. Brain Dev 2019; 41:327-333. [PMID: 30514608 DOI: 10.1016/j.braindev.2018.11.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 10/24/2018] [Accepted: 11/19/2018] [Indexed: 01/31/2023]
Abstract
PURPOSE Signals of some brain regions change along with development in T1-weighted imaging (T1WI) in infants. This study aimed to assess the association of the signal intensity of the pituitary stalk on thin-slice T1WI with infant age. METHODS This retrospective study was performed in 89 infants (gestational age [GA], 25-41 weeks; postmenstrual age [PMA], 36-46 weeks; chronological age [CA], 4-141 days) without intracranial abnormalities. The signal ratio of the pituitary stalk/pons on thin-slice T1WI was calculated, and its correlations with GA, PMA, and CA were assessed. Additionally, the signal ratio of the anterior pituitary gland/pons was calculated, and its correlation with that of the pituitary stalk was assessed. The signal intensity and distribution of the pituitary stalk were visually rated, and their correlations with GA, PMA, and CA were assessed. RESULTS The signal ratio of the pituitary stalk was significantly positively correlated with GA (P < 0.001) and negatively correlated with CA (P < 0.001), but was not correlated with PMA. Stepwise multiple regression revealed that CA was independently associated with the signal ratio of the pituitary stalk (P < 0.001). GA was significantly higher (P < 0.05) and CA was significantly lower (P < 0.05) in infants with a high signal intensity and wide distribution of high signal intensity of the pituitary stalk. CONCLUSIONS The signal intensity of the pituitary stalk on T1WI was negatively correlated with CA in infants, which might be related to postnatal changes in the pars tuberalis of the pituitary stalk after birth in infants.
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Affiliation(s)
- Takashi Okazaki
- Department of Radiology, Tokai University School of Medicine, 143 Shimokasuya, Isehara 259-1193, Japan
| | - Tetsu Niwa
- Department of Radiology, Tokai University School of Medicine, 143 Shimokasuya, Isehara 259-1193, Japan.
| | - Keiji Suzuki
- Department of Pediatrics, Tokai University School of Medicine, 143 Shimokasuya, Isehara 259-1193, Japan
| | - Shuhei Shibukawa
- Department of Radiology, Tokai University Hospital, 143 Shimokasuya, Isehara 259-1193, Japan
| | - Yutaka Imai
- Department of Radiology, Tokai University School of Medicine, 143 Shimokasuya, Isehara 259-1193, Japan
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Agnew ZK, Banissy MJ, McGettigan C, Walsh V, Scott SK. Investigating the Neural Basis of Theta Burst Stimulation to Premotor Cortex on Emotional Vocalization Perception: A Combined TMS-fMRI Study. Front Hum Neurosci 2018; 12:150. [PMID: 29867402 PMCID: PMC5962765 DOI: 10.3389/fnhum.2018.00150] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Accepted: 04/04/2018] [Indexed: 12/01/2022] Open
Abstract
Previous studies have established a role for premotor cortex in the processing of auditory emotional vocalizations. Inhibitory continuous theta burst transcranial magnetic stimulation (cTBS) applied to right premotor cortex selectively increases the reaction time to a same-different task, implying a causal role for right ventral premotor cortex (PMv) in the processing of emotional sounds. However, little is known about the functional networks to which PMv contribute across the cortical hemispheres. In light of these data, the present study aimed to investigate how and where in the brain cTBS affects activity during the processing of auditory emotional vocalizations. Using functional neuroimaging, we report that inhibitory cTBS applied to the right premotor cortex (compared to vertex control site) results in three distinct response profiles: following stimulation of PMv, widespread frontoparietal cortices, including a site close to the target site, and parahippocampal gyrus displayed an increase in activity, whereas the reverse response profile was apparent in a set of midline structures and right IFG. A third response profile was seen in left supramarginal gyrus in which activity was greater post-stimulation at both stimulation sites. Finally, whilst previous studies have shown a condition specific behavioral effect following cTBS to premotor cortex, we did not find a condition specific neural change in BOLD response. These data demonstrate a complex relationship between cTBS and activity in widespread neural networks and are discussed in relation to both emotional processing and the neural basis of cTBS.
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Affiliation(s)
- Zarinah K Agnew
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom.,Otolaryngology-Head & Neck Surgery Clinic, University of California, San Francisco, San Francisco, CA, United States
| | - Michael J Banissy
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom.,Department of Psychology, Goldsmiths, University of London, London, United Kingdom
| | | | - Vincent Walsh
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom
| | - Sophie K Scott
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom
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15
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Li C, Huang B, Zhang R, Ma Q, Yang W, Wang L, Wang L, Xu Q, Feng J, Liu L, Zhang Y, Huang R. Impaired topological architecture of brain structural networks in idiopathic Parkinson's disease: a DTI study. Brain Imaging Behav 2018; 11:113-128. [PMID: 26815739 DOI: 10.1007/s11682-015-9501-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Parkinson's disease (PD) is considered as a neurodegenerative disorder of the brain central nervous system. But, to date, few studies adopted the network model to reveal topological changes in brain structural networks in PD patients. Additionally, although the concept of rich club organization has been widely used to study brain networks in various brain disorders, there is no study to report the changed rich club organization of brain networks in PD patients. Thus, we collected diffusion tensor imaging (DTI) data from 35 PD patients and 26 healthy controls and adopted deterministic tractography to construct brain structural networks. During the network analysis, we calculated their topological properties, and built the rich club organization of brain structural networks for both subject groups. By comparing the between-group differences in topological properties and rich club organizations, we found that the connectivity strength of the feeder and local connections are lower in PD patients compared to those of the healthy controls. Furthermore, using a network-based statistic (NBS) approach, we identified uniformly significantly decreased connections in two modules, the limbic/paralimbic/subcortical module and the cognitive control/attention module, in patients compared to controls. In addition, for the topological properties of brain network topology in the PD patients, we found statistically increased shortest path length and decreased global efficiency. Statistical comparisons of nodal properties were also widespread in the frontal and parietal regions for the PD patients. These findings may provide useful information to better understand the abnormalities of brain structural networks in PD patients.
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Affiliation(s)
- Changhong Li
- Center for the Study of Applied Psychology, Key Laboratory of Mental Health and Cognitive Science of Guangdong Province, School of Psychology, Brain Study Institute, South China Normal University, Guangzhou, 510631, China
| | - Biao Huang
- Department of Radiology, Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, China.
| | - Ruibin Zhang
- Center for the Study of Applied Psychology, Key Laboratory of Mental Health and Cognitive Science of Guangdong Province, School of Psychology, Brain Study Institute, South China Normal University, Guangzhou, 510631, China
| | - Qing Ma
- Center for the Study of Applied Psychology, Key Laboratory of Mental Health and Cognitive Science of Guangdong Province, School of Psychology, Brain Study Institute, South China Normal University, Guangzhou, 510631, China
| | - Wanqun Yang
- Department of Radiology, Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, China
| | - Lijuan Wang
- Department of Neurology, Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, China
| | - Limin Wang
- Department of Neurology, Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, China
| | - Qin Xu
- Center for the Study of Applied Psychology, Key Laboratory of Mental Health and Cognitive Science of Guangdong Province, School of Psychology, Brain Study Institute, South China Normal University, Guangzhou, 510631, China
| | - Jieying Feng
- Department of Radiology, Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, China
| | - Liqing Liu
- Center for the Study of Applied Psychology, Key Laboratory of Mental Health and Cognitive Science of Guangdong Province, School of Psychology, Brain Study Institute, South China Normal University, Guangzhou, 510631, China
| | - Yuhu Zhang
- Department of Neurology, Guangdong Academy of Medical Sciences, Guangdong General Hospital, Guangzhou, China
| | - Ruiwang Huang
- Center for the Study of Applied Psychology, Key Laboratory of Mental Health and Cognitive Science of Guangdong Province, School of Psychology, Brain Study Institute, South China Normal University, Guangzhou, 510631, China.
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16
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Kim MJ, Brown AC, Mattek AM, Chavez SJ, Taylor JM, Palmer AL, Wu YC, Whalen PJ. The Inverse Relationship between the Microstructural Variability of Amygdala-Prefrontal Pathways and Trait Anxiety Is Moderated by Sex. Front Syst Neurosci 2016; 10:93. [PMID: 27899884 PMCID: PMC5110520 DOI: 10.3389/fnsys.2016.00093] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Accepted: 11/03/2016] [Indexed: 01/01/2023] Open
Abstract
Anxiety impacts the quality of everyday life and may facilitate the development of affective disorders, possibly through concurrent alterations in neural circuitry. Findings from multimodal neuroimaging studies suggest that trait-anxious individuals may have a reduced capacity for efficient communication between the amygdala and the ventral prefrontal cortex (vPFC). A diffusion-weighted imaging protocol with 61 directions was used to identify lateral and medial amygdala-vPFC white matter pathways. The structural integrity of both pathways was inversely correlated with self-reported levels of trait anxiety. When this mask from our first dataset was then applied to an independent validation dataset, both pathways again showed a consistent inverse relationship with trait anxiety. Importantly, a moderating effect of sex was found, demonstrating that the observed brain-anxiety relationship was stronger in females. These data reveal a potential neuroanatomical mediator of previously documented functional alterations in amygdala-prefrontal connectivity that is associated with trait anxiety, which might prove informative for future studies of psychopathology.
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Affiliation(s)
- M Justin Kim
- Department of Psychological and Brain Sciences, Dartmouth College Hanover, NH, USA
| | - Annemarie C Brown
- Department of Psychological and Brain Sciences, Dartmouth College Hanover, NH, USA
| | - Alison M Mattek
- Department of Psychological and Brain Sciences, Dartmouth College Hanover, NH, USA
| | - Samantha J Chavez
- Department of Psychological and Brain Sciences, Dartmouth CollegeHanover, NH, USA; Division of Epidemiology, The Ohio State University College of Public HealthColumbus, OH, USA
| | - James M Taylor
- Department of Psychological and Brain Sciences, Dartmouth College Hanover, NH, USA
| | - Amy L Palmer
- Department of Psychological and Brain Sciences, Dartmouth College Hanover, NH, USA
| | - Yu-Chien Wu
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine Indianapolis, IN, USA
| | - Paul J Whalen
- Department of Psychological and Brain Sciences, Dartmouth College Hanover, NH, USA
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17
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Khalil AA, Hohenhaus M, Kunze C, Schmidt W, Brunecker P, Villringer K, Merboldt KD, Frahm J, Fiebach JB. Sensitivity of Diffusion-Weighted STEAM MRI and EPI-DWI to Infratentorial Ischemic Stroke. PLoS One 2016; 11:e0161416. [PMID: 27529697 PMCID: PMC4987060 DOI: 10.1371/journal.pone.0161416] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 08/01/2016] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES To assess the sensitivity of stimulated echo acquisition mode diffusion weighted imaging (STEAM-DWI) to ischemic stroke in comparison to echo-planar imaging diffusion weighted imaging (EPI-DWI) in the infratentorial compartment. METHODS Fifty-seven patients presenting with clinical features of infratentorial stroke underwent STEAM-DWI, high-resolution EPI-DWI (HR-DWI, 2.5 mm slice thickness) and low-resolution EPI-DWI (LR-DWI, 5 mm slice thickness). Four readers assessed the presence of ischemic lesions and artifacts. Agreement between sequences and interobserver agreement on the presence of ischemia were calculated. The sensitivities of the DWI sequences were calculated in 45 patients with a confirmed diagnosis of infratentorial stroke. RESULTS Median time from symptom onset to imaging was 24 hours. STEAM-DWI agreed with LR-DWI in 89.5% of cases (kappa = 0.72, p<0.0001) and with HR-DWI in 89.5% of cases (kappa = 0.68, p<0.0001). STEAM-DWI showed fewer intraparenchymal artifacts (1/57) than HR-DWI (44/57) and LR-DWI (41/57). Ischemia was visible in 87% of cases for LR-DWI, 93% of cases for HR-DWI, and 89% of cases for STEAM-DWI. Interobserver agreement was good for STEAM-DWI (kappa = 0.62, p<0.0001). CONCLUSIONS Compared to the best currently available MR sequence for detecting ischemia (HR-DWI), STEAM-DWI shows fewer artifacts and a similar sensitivity to infratentorial stroke.
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Affiliation(s)
- Ahmed A. Khalil
- Center for Stroke Research Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
- NeuroCure Cluster of Excellence, Charité – Universitätsmedizin Berlin, Berlin, Germany
- International Graduate Program Medical Neurosciences, Charité – Universitätsmedizin Berlin, Berlin, Germany
- * E-mail:
| | - Marc Hohenhaus
- Klinik für Neurochirurgie, Universitätsklinikum Freiburg, Freiburg im Breisgau, Germany
| | - Claudia Kunze
- Center for Stroke Research Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Wolf Schmidt
- Center for Stroke Research Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Peter Brunecker
- Center for Stroke Research Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Kersten Villringer
- Center for Stroke Research Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
| | - Klaus-Dietmar Merboldt
- Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany
| | - Jens Frahm
- Biomedizinische NMR Forschungs GmbH am Max-Planck-Institut für biophysikalische Chemie, Göttingen, Germany
| | - Jochen B. Fiebach
- Center for Stroke Research Berlin, Charité – Universitätsmedizin Berlin, Berlin, Germany
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18
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Azuma M, Hirai T, Shigematsu Y, Kitajima M, Kai Y, Yano S, Nakamura H, Makino K, Iryo Y, Yamashita Y. Evaluation of Intracranial Dural Arteriovenous Fistulas: Comparison of Unenhanced 3T 3D Time-of-flight MR Angiography with Digital Subtraction Angiography. Magn Reson Med Sci 2015; 14:285-93. [PMID: 25994036 DOI: 10.2463/mrms.2014-0120] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE We compared gross characterization of intracranial dural arteriovenous fistulas (DAVFs) between unenhanced 3-tesla 3-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) and digital subtraction angiography (DSA). METHODS We subjected 26 consecutive patients with intracranial DAVF to unenhanced 3T 3D TOF MRA and to DSA. Two independent sets of observers inspected the main arterial feeders, fistula site, and venous drainage pattern on MRA and DSA images. Interobserver and intermodality agreements were assessed by k statistics. RESULTS Interobserver agreement was excellent for fistula site (κ = 0.919; 95% confidence interval [CI], 0.805 to 1.000), good for main arterial feeders (κ = 0.711; 95% CI, 0.483 to 0.984), and very good for venous drainage (κ = 0.900; 95% CI, 0.766 to 1.000). Intermodality agreement was excellent for fistula site (κ = 0.968; 95% CI, 0.906 to 1.000) and good for main arterial feeder (κ = 0.809; 95% CI, 0.598 to 1.000) and venous drainage (κ = 0.837; 95% CI, 0.660 to 1.000). CONCLUSION Gross characterization of intracranial DAVF was similar for both imaging modalities, but unenhanced 3T 3D TOF MRA cannot replace DSA.
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Affiliation(s)
- Minako Azuma
- Department of Diagnostic Radiology,Graduate School of Medical Sciences, Kumamoto University
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19
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Le Bras A, Raoult H, Ferré JC, Ronzière T, Gauvrit JY. Optimal MRI sequence for identifying occlusion location in acute stroke: which value of time-resolved contrast-enhanced MRA? AJNR Am J Neuroradiol 2015; 36:1081-8. [PMID: 25767186 DOI: 10.3174/ajnr.a4264] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 12/21/2014] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Identifying occlusion location is crucial for determining the optimal therapeutic strategy during the acute phase of ischemic stroke. The purpose of this study was to assess the diagnostic efficacy of MR imaging, including conventional sequences plus time-resolved contrast-enhanced MRA in comparison with DSA for identifying arterial occlusion location. MATERIALS AND METHODS Thirty-two patients with 34 occlusion levels referred for thrombectomy during acute cerebral stroke events were consecutively included from August 2010 to December 2012. Before thrombectomy, we performed 3T MR imaging, including conventional 3D-TOF and gradient-echo T2 sequences, along with time-resolved contrast-enhanced MRA of the extra- and intracranial arteries. The 3D-TOF, gradient-echo T2, and time-resolved contrast-enhanced MRA results were consensually assessed by 2 neuroradiologists and compared with prethrombectomy DSA results in terms of occlusion location. The Wilcoxon test was used for statistical analysis to compare MR imaging sequences with DSA, and the κ coefficient was used to determine intermodality agreement. RESULTS The occlusion level on the 3D-TOF and gradient-echo T2 images differed significantly from that of DSA (P < .001 and P = .002, respectively), while no significant difference was observed between DSA and time-resolved contrast-enhanced MRA (P = .125). κ coefficients for intermodality agreement with DSA (95% CI, percentage agreement) were 0.43 (0.3%-0.6; 62%), 0.32 (0.2%-0.5; 56%), and 0.81 (0.6%-1.0; 88%) for 3D-TOF, gradient-echo T2, and time-resolved contrast-enhanced MRA, respectively. CONCLUSIONS The time-resolved contrast-enhanced MRA sequence proved reliable for identifying occlusion location in acute stroke with performance superior to that of 3D-TOF and gradient-echo T2 sequences.
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Affiliation(s)
- A Le Bras
- From the Departments of Neuroradiology (A.L.B., H.R., J.-C.F., J.-Y.G.)
| | - H Raoult
- From the Departments of Neuroradiology (A.L.B., H.R., J.-C.F., J.-Y.G.) Unité VISAGE U746 INSERM-INRIA, IRISA UMR CNRS 6074 (H.R., J.-C.F., J.-Y.G.), University of Rennes, Rennes, France
| | - J-C Ferré
- From the Departments of Neuroradiology (A.L.B., H.R., J.-C.F., J.-Y.G.) Unité VISAGE U746 INSERM-INRIA, IRISA UMR CNRS 6074 (H.R., J.-C.F., J.-Y.G.), University of Rennes, Rennes, France
| | - T Ronzière
- Neurology (T.R.), Centre Hospitalier Universitaire Rennes, Rennes, France
| | - J-Y Gauvrit
- From the Departments of Neuroradiology (A.L.B., H.R., J.-C.F., J.-Y.G.) Unité VISAGE U746 INSERM-INRIA, IRISA UMR CNRS 6074 (H.R., J.-C.F., J.-Y.G.), University of Rennes, Rennes, France
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20
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Franke P, Markl M, Heinzelmann S, Vaith P, Bürk J, Langer M, Geiger J. Evaluation of a 32-channel versus a 12-channel head coil for high-resolution post-contrast MRI in giant cell arteritis (GCA) at 3T. Eur J Radiol 2014; 83:1875-80. [DOI: 10.1016/j.ejrad.2014.06.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 06/24/2014] [Indexed: 10/25/2022]
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Advanced Imaging Techniques in the Diagnosis of Nonlesional Epilepsy: MRI, MRS, PET, and SPECT. Epilepsy Curr 2014; 14:121-4. [PMID: 24940151 DOI: 10.5698/1535-7597-14.3.121] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Once patients have a diagnosis of localization related epilepsy (LRE), it is critical to further classify those patients into lesional or nonlesional for treatment and prognostic reasons. An individual with LRE may be classified as nonlesional for two reasons: 1) a lesion may not exist; that is, the structural abnormality that gives rise to seizures may be at the channel level or be spatially distributed in such a way that it would not be accurately termed a lesion, or 2) a lesion exists but is so subtle that standard clinical imaging is not sensitive enough to discriminate between the lesion and surrounding healthy brain tissue. As with any technology and disease process, this definition is dynamic, as we know that future imaging techniques will be developed and new disease mechanisms will be discovered, making detection of the epileptogenic underlying abnormality an ever-changing target.
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22
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Ferré JC, Raoult H, Breil S, Carsin-Nicol B, Ronzière T, Gauvrit JY. Supra-aortic arteries: three-dimensional time-resolved k-t BLAST contrast-enhanced MRA using a nondedicated body coil at 3 tesla in acute ischemic stroke. J Magn Reson Imaging 2013; 40:1056-63. [PMID: 24222649 DOI: 10.1002/jmri.24466] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 09/14/2013] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To assess the image quality and diagnostic performance achieved by using supra-aortic 3D-TR-CE-k-t BLAST MRA and a nondedicated body coil as compared with conventional CE-MRA in patients with acute ischemic stroke. MATERIALS AND METHODS In this prospective study, 36 consecutive patients with a suspected acute ischemic stroke underwent both k-t BLAST MRA and conventional CE-MRA. Image quality was assessed using visual and quantitative criteria and the techniques were compared. Both techniques were compared for degree of visual and quantitative measurement of carotid stenosis. RESULTS Delineation of vessel lumen and overall diagnostic confidence were significantly better with CE-MRA, respectively 3.4 ± 0.5 and 3.3 ± 0.6 (mean score ± SD), than with k-t BLAST MRA, respectively 2.8 ± 0.4 and 2.9 ± 0.5 (P < 0.02). SNR and CNR were significantly higher for k-t BLAST MRA, respectively 33.5 ± 19.3 and 27.9 ± 19.3, than for CE-MRA, respectively 25.7 ± 10 and 20.4 ± 8.4 (P < 0.03). Intertechnique agreement was good for carotid stenosis characterization (κ = .763). For the 14 relevant stenosis, stenosis measurements were highly correlated between techniques (0.96; P < 0.0001). The Bland-Altman plot showed a low bias in assessment of the degree of stenosis (mean bias 2.1% ± 7.7). CONCLUSION k-t BLAST MRA using a nondedicated coil offering and dynamic information was a effective diagnostic tool for detection and characterization of carotid stenosis.
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Affiliation(s)
- Jean-Christophe Ferré
- CHU Rennes, Department of Neuroradiology, University Hospital of Rennes, Rennes, France
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Reiss-Zimmermann M, Gutberlet M, Köstler H, Fritzsch D, Hoffmann KT. Improvement of SNR and acquisition acceleration using a 32-channel head coil compared to a 12-channel head coil at 3T. Acta Radiol 2013; 54:702-8. [PMID: 23474767 DOI: 10.1177/0284185113479051] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Magnetic resonance imaging (MRI) techniques continue to improve in manifold ways. Besides field strength and sequence optimization, technical advances in coil design and sensitivity yield to increase the signal detection and therefore improve image quality. PURPOSE To evaluate the performance of signal-to-noise ratio (SNR) and parallel acquisition technique (PAT) acceleration of a dedicated 32-channel head coil compared with a standard 12-channel head coil. MATERIAL AND METHODS In a clinical 3T setting, spatial resolved SNR values for unaccelerated imaging and PAT with acceleration factors of 2-6 of a 32-channel head coil were evaluated in relation to a 12-channel head coil. SNR was determined quantitatively using proton-density-weighted in-vivo examinations in five healthy volunteers. Quantitative SNR maps for unaccelerated and PAT imaging were calculated using unfiltered MR raw data. RESULTS Up to three-fold higher SNR values were achieved with the 32-channel head coil, which diminished towards the center to an increase of 40% compared with the 12-channel head coil. When using PAT, the 32-channel head coil resulted in a lower spatial-dependent quantitative noise enhancement, varying between 0% at R = 2 and 33% at R = 5. CONCLUSION The 32-channel head coil provided superior SNR both with and without PAT compared with a 12-channel head coil, especially close to the brain surface. Using PAT, the unavoidable noise enhancement is diminished up to acceleration factors of 6 for the 32-channel head coil. Therefore, the 32-channel head coil is considered as a preferable tool for high-resolution neuroradiological imaging.
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Affiliation(s)
| | | | - Herbert Köstler
- Institute of Radiology, University of Würzburg, Würzburg, Germany
| | - Dominik Fritzsch
- Department of Neuroradiology, University Hospital Leipzig, Leipzig
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Anteraper SA, Whitfield-Gabrieli S, Keil B, Shannon S, Gabrieli JD, Triantafyllou C. Exploring functional connectivity networks with multichannel brain array coils. Brain Connect 2013; 3:302-15. [PMID: 23510203 DOI: 10.1089/brain.2012.0113] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The use of multichannel array head coils in functional and structural magnetic resonance imaging (MRI) provides increased signal-to-noise ratio (SNR), higher sensitivity, and parallel imaging capabilities. However, their benefits remain to be systematically explored in the context of resting-state functional connectivity MRI (fcMRI). In this study, we compare signal detectability within and between commercially available multichannel brain coils, a 32-Channel (32Ch), and a 12-Channel (12Ch) at 3T, in a high-resolution regime to accurately map resting-state networks. We investigate whether the 32Ch coil can extract and map fcMRI more efficiently and robustly than the 12Ch coil using seed-based and graph-theory-based analyses. Our findings demonstrate that although the 12Ch coil can be used to reveal resting-state connectivity maps, the 32Ch coil provides increased detailed functional connectivity maps (using seed-based analysis) as well as increased global and local efficiency, and cost (using graph-theory-based analysis), in a number of widely reported resting-state networks. The exploration of subcortical networks, which are scarcely reported due to limitations in spatial-resolution and coil sensitivity, also proved beneficial with the 32Ch coil. Further, comparisons regarding the data acquisition time required to successfully map these networks indicated that scan time can be significantly reduced by 50% when a coil with increased number of channels (i.e., 32Ch) is used. Switching to multichannel arrays in resting-state fcMRI could, therefore, provide both detailed functional connectivity maps and acquisition time reductions, which could further benefit imaging special subject populations, such as patients or pediatrics who have less tolerance in lengthy imaging sessions.
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Affiliation(s)
- Sheeba Arnold Anteraper
- Athinoula A. Martinos Imaging Center at McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, Massachusetts MA 02139, USA.
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Uetani H, Akter M, Hirai T, Shigematsu Y, Kitajima M, Kai Y, Yano S, Nakamura H, Makino K, Azuma M, Murakami R, Yamashita Y. Can 3T MR angiography replace DSA for the identification of arteries feeding intracranial meningiomas? AJNR Am J Neuroradiol 2012; 34:765-72. [PMID: 23079409 DOI: 10.3174/ajnr.a3284] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE For identifying the arterial feeders of meningiomas, the usefulness of 3D TOF MRA at 3T has not been systematically investigated. This study was intended to assess whether unenhanced 3D TOF MRA at 3T can replace DSA for the identification of arteries feeding intracranial meningiomas and whether it is useful for assessing their dural attachment. MATERIALS AND METHODS Twenty-one consecutive patients with intracranial meningiomas (18 women, 3 men; aged 42-77 years, mean 57 years) underwent DSA, conventional MR imaging, and 3D TOF MRA. Two neuroradiologists independently evaluated the primary and secondary feeders of each tumor on maximum-intensity-projection and source MRA images. They also identified the location of dural attachments based on information from MR imaging/MRA images. Interobserver and intermodality agreement was determined by calculating the κ coefficient. RESULTS For the identification of primary and secondary feeders on MRA images, interobserver agreement was very good (κ=0.83; 95% CI, 0.66-1.00) and moderate (κ=0.58; 95% CI, 0.34-0.82) and intermodality agreement (consensus reading of MRA versus DSA findings) was excellent (κ=0.94; 95% CI, 0.84-1.00) and good (κ=0.72; 95% CI, 0.51-0.93), respectively. With respect to the dural attachment of meningiomas, interobserver agreement was very good (κ=0.95; 95% CI, 0.84-1.00). The agreement in the diagnosis between MR imaging/MRA and surgery was excellent (κ=1.00). CONCLUSIONS Unenhanced 3D TOF MRA at 3T cannot at present supplant DSA for the identification of the feeding arteries of intracranial meningiomas. This information may be useful for evaluating their dural attachment.
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Affiliation(s)
- H Uetani
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
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Morelli JN, Saettele MR, Rangaswamy RA, Vu L, Gerdes CM, Zhang W, Ai F. Echo planar diffusion-weighted imaging: possibilities and considerations with 12- and 32-channel head coils. J Clin Imaging Sci 2012; 2:31. [PMID: 22754745 PMCID: PMC3385505 DOI: 10.4103/2156-7514.96548] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 04/04/2012] [Indexed: 11/25/2022] Open
Abstract
Interest in clinical brain magnetic resonance imaging using 32-channel head coils for signal reception continues to increase. The present investigation assesses possibilities for improving diffusion-weighted image quality using a 32-channel in comparison to a conventional 12-channel coil. The utility of single-shot (ss) and an approach to readout-segmented (rs) echo planar imaging (EPI) are examined using both head coils. Substantial image quality improvements are found with rs-EPI. Imaging with a 32-channel head coil allows for implementation of greater parallel imaging acceleration factors or acquisition of scans at a higher resolution. Specifically, higher resolution imaging with rs-EPI can be achieved by increasing the number of readout segments without increasing echo-spacing or echo time to the degree necessary with ss-EPI — a factor resulting in increased susceptibility artifact and reduced signal-to-noise with the latter.
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Hillenbrand CM, Reykowski A. MR Imaging of the Newborn: a technical perspective. Magn Reson Imaging Clin N Am 2012; 20:63-79. [PMID: 22118593 DOI: 10.1016/j.mric.2011.10.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This article discusses neonatal magnetic resonance (MR) imaging and reviews equipment and procedures for MR-related transport, sedation, monitoring, and scanning. MR is gaining importance in the diagnosis and clinical management of critically ill, and often very low birth weight infants, so research is ongoing to make transport and examination safer and imaging more successful. Efforts are focused on integration of dedicated neonate MR scanners in neonatal intensive care units, improvements in incubator technology and handling, and more efficient use of scan/sedation time by choosing dedicated neonate coil arrays that improve the signal-to-noise-ratio and facilitate the choice of modern imaging techniques.
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Affiliation(s)
- Claudia M Hillenbrand
- Division of Translational Imaging Research, Department of Radiological Sciences, St Jude Children's Research Hospital, Memphis, TN 38105, USA
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Nishimura S, Hirai T, Shigematsu Y, Kitajima M, Morioka M, Kai Y, Minoda R, Uetani H, Murakami R, Yamashita Y. Evaluation of brain and head and neck tumors with 4D contrast-enhanced MR angiography at 3T. AJNR Am J Neuroradiol 2012; 33:445-8. [PMID: 22116118 DOI: 10.3174/ajnr.a2819] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Systematic assessment of brain and head and neck tumors with 4D-CE-MRA at 3T has not been investigated. The purpose of this study was to test the hypothesis that 4D-CE-MRA at 3T can replace DSA in the identification of feeding arteries and tumor stain to plan interventional procedures in hypervascular brain and head and neck tumors. MATERIALS AND METHODS Fifteen consecutive patients with brain and head and neck tumors underwent 4D-CE-MRA at 3T and DSA. 4D-CE-MRA combined randomly segmented central k-space ordering, keyhole imaging, SENSE, and half-Fourier imaging. We obtained 30 dynamic scans every 1.9 seconds at an acquired spatial resolution of 0.9 × 0.9 × 1.5 mm; the matrix was 256 × 256. Two independent observers inspected the 4D-CE-MRA images for the main arterial feeders and tumor stain. Interobserver and intermodality agreement was assessed by κ statistics. RESULTS For 4D-CE-MRA, the interobserver agreement was fair with respect to the main arterial feeders and very good for the degree of tumor stain (κ = 0.28 and 0.87, respectively). Intermodality agreement was moderate for the main arterial feeders (κ = 0.45) and good for the tumor stain (κ = 0.74). CONCLUSIONS Although 4D-CE-MRA may be useful for evaluating tumor stain in hypervascular brain and head and neck tumors, it is not able to replace DSA in planning interventional procedures.
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Affiliation(s)
- S Nishimura
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan
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McGettigan C, Evans S, Rosen S, Agnew ZK, Shah P, Scott SK. An application of univariate and multivariate approaches in FMRI to quantifying the hemispheric lateralization of acoustic and linguistic processes. J Cogn Neurosci 2012; 24:636-52. [PMID: 22066589 PMCID: PMC3376446 DOI: 10.1162/jocn_a_00161] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The question of hemispheric lateralization of neural processes is one that is pertinent to a range of subdisciplines of cognitive neuroscience. Language is often assumed to be left-lateralized in the human brain, but there has been a long running debate about the underlying reasons for this. We addressed this problem with fMRI by identifying the neural responses to amplitude and spectral modulations in speech and how these interact with speech intelligibility to test previous claims for hemispheric asymmetries in acoustic and linguistic processes in speech perception. We used both univariate and multivariate analyses of the data, which enabled us to both identify the networks involved in processing these acoustic and linguistic factors and to test the significance of any apparent hemispheric asymmetries. We demonstrate bilateral activation of superior temporal cortex in response to speech-derived acoustic modulations in the absence of intelligibility. However, in a contrast of amplitude-modulated and spectrally modulated conditions that differed only in their intelligibility (where one was partially intelligible and the other unintelligible), we show a left dominant pattern of activation in STS, inferior frontal cortex, and insula. Crucially, multivariate pattern analysis showed that there were significant differences between the left and the right hemispheres only in the processing of intelligible speech. This result shows that the left hemisphere dominance in linguistic processing does not arise because of low-level, speech-derived acoustic factors and that multivariate pattern analysis provides a method for unbiased testing of hemispheric asymmetries in processing.
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Agnew ZK, McGettigan C, Scott SK. Discriminating between auditory and motor cortical responses to speech and nonspeech mouth sounds. J Cogn Neurosci 2011; 23:4038-47. [PMID: 21812557 PMCID: PMC3361723 DOI: 10.1162/jocn_a_00106] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Several perspectives on speech perception posit a central role for the representation of articulations in speech comprehension, supported by evidence for premotor activation when participants listen to speech. However, no experiments have directly tested whether motor responses mirror the profile of selective auditory cortical responses to native speech sounds or whether motor and auditory areas respond in different ways to sounds. We used fMRI to investigate cortical responses to speech and nonspeech mouth (ingressive click) sounds. Speech sounds activated bilateral superior temporal gyri more than other sounds, a profile not seen in motor and premotor cortices. These results suggest that there are qualitative differences in the ways that temporal and motor areas are activated by speech and click sounds: Anterior temporal lobe areas are sensitive to the acoustic or phonetic properties, whereas motor responses may show more generalized responses to the acoustic stimuli.
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Affiliation(s)
- Zarinah K Agnew
- Institute for Cognitive Neuroscience, University College London, UK
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