1
|
Jiang M, Cao F, Zhang Q, Qi Z, Gao Y, Zhang Y, Song B, Wu C, Li M, Xu Y, Zhang X, Wang Y, Wei M, Ji X. Model-predicted brain temperature computational imaging by multimodal noninvasive functional neuromonitoring of cerebral oxygen metabolism and hemodynamics: MRI-derived and clinical validation. J Cereb Blood Flow Metab 2024:271678X241270485. [PMID: 39129194 DOI: 10.1177/0271678x241270485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/13/2024]
Abstract
Brain temperature, a crucial yet under-researched neurophysiological parameter, is governed by the equilibrium between cerebral oxygen metabolism and hemodynamics. Therapeutic hypothermia has been demonstrated as an effective intervention for acute brain injuries, enhancing survival rates and prognosis. The success of this treatment hinges on the precise regulation of brain temperature. However, the absence of comprehensive brain temperature monitoring methods during therapy, combined with a limited understanding of human brain heat transmission mechanisms, significantly hampers the advancement of hypothermia-based neuroprotective therapies. Leveraging the principles of bioheat transfer and MRI technology, this study conducted quantitative analyses of brain heat transfer during mild hypothermia therapy. Utilizing MRI, we reconstructed brain structures, estimated cerebral blood flow and oxygen consumption parameters, and developed a brain temperature calculation model founded on bioheat transfer theory. Employing computational cerebral hemodynamic simulation analysis, we established an intracranial arterial fluid dynamics model to predict brain temperature variations across different therapeutic hypothermia modalities. We introduce a noninvasive, spatially resolved, and optimized mathematical bio-heat model that synergizes model-predicted and MRI-derived data for brain temperature prediction and imaging. Our findings reveal that the brain temperature images generated by our model reflect distinct spatial variations across individual participants, aligning with experimentally observed temperatures.
Collapse
Affiliation(s)
- Miaowen Jiang
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Fuzhi Cao
- School of Engineering Medicine, Beihang University, Beijing 100083, China
| | - Qihan Zhang
- Department of Neurology and Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Zhengfei Qi
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Yuan Gao
- School of Engineering Medicine, Beihang University, Beijing 100083, China
| | - Yang Zhang
- Department of Neurology and Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Baoyin Song
- Department of Neurology and Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Chuanjie Wu
- Department of Neurology and Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Ming Li
- China-America Institute of Neuroscience and Beijing Institute of Geriatrics, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Yongbo Xu
- Clinical College of Neurology, Neurosurgery and Neurorehabilitation, Tianjin Medical University, Tianjin 300203, China
| | - Xin Zhang
- Brainnetome Center, Laboratory of Brain Atlas and Brain-inspired Intelligence, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China
| | - Yuan Wang
- Department of Neurology and Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Ming Wei
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
- Clinical College of Neurology, Neurosurgery and Neurorehabilitation, Tianjin Medical University, Tianjin 300203, China
- Tianjin University, Tianjin Huanhu Hospital, Tianjin 300203, China
| | - Xunming Ji
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
- Department of Neurology and Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
- China-America Institute of Neuroscience and Beijing Institute of Geriatrics, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| |
Collapse
|
2
|
Zoelch N, Heimer J, Richter H, Luechinger R, Archibald J, Thali MJ, Gascho D. In situ temperature determination using magnetic resonance spectroscopy thermometry for noninvasive postmortem examinations. NMR IN BIOMEDICINE 2024:e5171. [PMID: 38757603 DOI: 10.1002/nbm.5171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 03/28/2024] [Accepted: 04/18/2024] [Indexed: 05/18/2024]
Abstract
Magnetic resonance spectroscopy (MRS) thermometry offers a noninvasive, localized method for estimating temperature by leveraging the temperature-dependent chemical shift of water relative to a temperature-stable reference metabolite under suitable calibration. Consequentially, this technique has significant potential as a tool for postmortem MR examinations in forensic medicine and pathology. In these examinations, the deceased are examined at a wide range of body temperatures, and MRS thermometry may be used for the temperature adjustment of magnetic resonance imaging (MRI) protocols or for corrections in the analysis of MRI or MRS data. However, it is not yet clear to what extent postmortem changes may influence temperature estimation with MRS thermometry. In addition, N-acetylaspartate, which is commonly used as an in vivo reference metabolite, is known to decrease with increasing postmortem interval (PMI). This study shows that lactate, which is not only present in significant amounts postmortem but also has a temperature-stable chemical shift, can serve as a suitable reference metabolite for postmortem MRS thermometry. Using lactate, temperature estimation in postmortem brain tissue of severed sheep heads was accurate up to 60 h after death, with a mean absolute error of less than 0.5°C. For this purpose, published calibrations intended for in vivo measurements were used. Although postmortem decomposition resulted in severe metabolic changes, no consistent deviations were observed between measurements with an MR-compatible temperature probe and MRS thermometry with lactate as a reference metabolite. In addition, MRS thermometry was applied to 84 deceased who underwent a MR examination as part of the legal examination. MRS thermometry provided plausible results of brain temperature in comparison with rectal temperature. Even for deceased with a PMI well above 60 h, MRS thermometry still provided reliable readings. The results show a good suitability of MRS thermometry for postmortem examinations in forensic medicine.
Collapse
Affiliation(s)
- Niklaus Zoelch
- Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
- Department of Adult Psychiatry and Psychotherapy, Psychiatric University Hospital Zurich and University of Zurich, Zurich, Switzerland
| | - Jakob Heimer
- Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| | - Henning Richter
- Clinic of Diagnostic Imaging, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Roger Luechinger
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
| | - Jessica Archibald
- Department of Radiology, Weill Cornell Medicine, New York, New York, USA
| | - Michael J Thali
- Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| | - Dominic Gascho
- Department of Forensic Medicine and Imaging, Institute of Forensic Medicine, University of Zurich, Zurich, Switzerland
| |
Collapse
|
3
|
Zhang L, Antonacci M, Burant A, McCallister A, Kelley M, Bryden N, McHugh C, Atalla S, Holmes L, Katz L, Branca RT. Absolute thermometry of human brown adipose tissue by magnetic resonance with laser polarized 129Xe. COMMUNICATIONS MEDICINE 2023; 3:147. [PMID: 37848608 PMCID: PMC10582175 DOI: 10.1038/s43856-023-00374-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 09/28/2023] [Indexed: 10/19/2023] Open
Abstract
BACKGROUND Absolute temperature measurements of tissues inside the human body are difficult to perform non-invasively. Yet, for brown adipose tissue (BAT), these measurements would enable direct monitoring of its thermogenic activity and its association with metabolic health. METHODS Here, we report direct measurement of absolute BAT temperature in humans during cold exposure by magnetic resonance (MR) with laser polarized xenon gas. This methodology, which leverages on the sensitivity of the chemical shift of the 129Xe isotope to temperature-induced changes in fat density, is first calibrated in vitro and then tested in vivo in rodents. Finally, it is used in humans along with positron emission tomography (PET) scans with fluorine-18-fluorodeoxyglucose to detect BAT thermogenic activity during cold exposure. RESULTS Absolute temperature measurements, obtained in rodents with an experimental error of 0.5 °C, show only a median deviation of 0.12 °C against temperature measurements made using a pre-calibrated optical temperature probe. In humans, enhanced uptake of 129Xe in BAT during cold exposure leads to background-free detection of this tissue by MR. Global measurements of supraclavicular BAT temperature, made over the course of four seconds and with an experimental error ranging from a minimum of 0.4 °C to more than 2 °C, in case of poor shimming, reveal an average BAT temperature of 38.8° ± 0.8 °C, significantly higher (p < 0.02 two-sided t test) than 37.7 °C. Hot BAT is also detected in participants with a PET scan negative for BAT. CONCLUSIONS Non-invasive, radiation-free measurements of BAT temperature by MRI with hyperpolarized 129Xe may enable longitudinal monitoring of human BAT activity under various stimulatory conditions.
Collapse
Affiliation(s)
- Le Zhang
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Small Animal Imaging Laboratory, Department of Cancer Physiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, 33612, USA
| | - Michael Antonacci
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Department of Physics, Saint Vincent College, 300 Fraser Purchase Rd., Latrobe, PA, 15650, USA
| | - Alex Burant
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Department of Physics, University of Arizona, 1118 E Fourth Street, PO Box 210081, Tucson, AZ, 85721, USA
| | - Andrew McCallister
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
| | - Michele Kelley
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
| | - Nicholas Bryden
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
| | - Christian McHugh
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
| | - Sebastian Atalla
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
| | - Leah Holmes
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
| | - Laurence Katz
- Department of Emergency Medicine, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA
| | - Rosa Tamara Branca
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA.
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, 27599, Chapel Hill, NC, USA.
| |
Collapse
|
4
|
Spatio-temporal metabolic rewiring in the brain of TgF344-AD rat model of Alzheimer's disease. Sci Rep 2022; 12:16958. [PMID: 36216838 PMCID: PMC9550832 DOI: 10.1038/s41598-022-20962-6] [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] [Received: 05/10/2022] [Accepted: 09/21/2022] [Indexed: 12/29/2022] Open
Abstract
Brain damage associated with Alzheimer's disease (AD) occurs even decades before the symptomatic onset, raising the need to investigate its progression from prodromal stages. In this context, animal models that progressively display AD pathological hallmarks (e.g. TgF344-AD) become crucial. Translational technologies, such as magnetic resonance spectroscopy (MRS), enable the longitudinal metabolic characterization of this disease. However, an integrative approach is required to unravel the complex metabolic changes underlying AD progression, from early to advanced stages. TgF344-AD and wild-type (WT) rats were studied in vivo on a 7 Tesla MRI scanner, for longitudinal quantitative assessment of brain metabolic profile changes using MRS. Disease progression was investigated at 4 time points, from 9 to 18 months of age, and in 4 regions: cortex, hippocampus, striatum, and thalamus. Compared to WT, TgF344-AD rats replicated common findings in AD patients, including decreased N-acetylaspartate in the cortex, hippocampus and thalamus, and decreased glutamate in the thalamus and striatum. Different longitudinal evolution of metabolic concentration was observed between TgF344-AD and WT groups. Namely, age-dependent trajectories differed between groups for creatine in the cortex and thalamus and for taurine in cortex, with significant decreases in Tg344-AD animals; whereas myo-inositol in the thalamus and striatum showed greater increase along time in the WT group. Additional analysis revealed divergent intra- and inter-regional metabolic coupling in each group. Thus, in cortex, strong couplings of N-acetylaspartate and creatine with myo-inositol in WT, but with taurine in TgF344-AD rats were observed; whereas in the hippocampus, myo-inositol, taurine and choline compounds levels were highly correlated in WT but not in TgF344-AD animals. Furthermore, specific cortex-hippocampus-striatum metabolic crosstalks were found for taurine levels in the WT group but for myo-inositol levels in the TgF344-AD rats. With a systems biology perspective of metabolic changes in AD pathology, our results shed light into the complex spatio-temporal metabolic rewiring in this disease, reported here for the first time. Age- and tissue-dependent imbalances between myo-inositol, taurine and other metabolites, such as creatine, unveil their role in disease progression, while pointing to the inadequacy of the latter as an internal reference for quantification.
Collapse
|
5
|
Dong Z, Kantrowitz JT, Mann JJ. Improving the reproducibility of proton magnetic resonance spectroscopy brain thermometry: Theoretical and empirical approaches. NMR IN BIOMEDICINE 2022; 35:e4749. [PMID: 35475306 DOI: 10.1002/nbm.4749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 02/25/2022] [Accepted: 04/19/2022] [Indexed: 06/14/2023]
Abstract
In proton magnetic resonance spectroscopy (1 H MRS)-based thermometry of brain, averaging temperatures measured from more than one reference peak offers several advantages, including improving the reproducibility (i.e., precision) of the measurement. This paper proposes theoretically and empirically optimal weighting factors to improve the weighted average of temperatures measured from three references. We first proposed concepts of equivalent noise and equivalent signal-to-noise ratio in terms of frequency measurement and a concept of relative frequency that allows the combination of different peaks in a spectrum for improving the precision of frequency measurement. Based on these, we then derived a theoretically optimal weighting factor and proposed an empirical weighting factor, both involving equivalent noise levels, for a weighted average of temperatures measured from three references (i.e., the singlets of NAA, Cr, and Ch in the 1 H MR spectrum). We assessed these two weighting factors by comparing their errors in measurement of temperatures with the errors of temperatures measured from individual references; we also compared these two new weighting factors with two previously proposed weighting factors. These errors were defined as the standard deviations in repeated measurements or in Monte Carlo studies. Both the proposed theoretical and empirical weighting factors outperformed the two previously proposed weighting factors as well as the three individual references in all phantom and in vivo experiments. In phantom experiments with 4- or 10-Hz line broadening, the theoretical weighting factor outperformed the empirical one, but the latter was superior in all other repeated and Monte Carlo tests performed on phantom and in vivo data. The proposed weighting factors are superior to the two previously proposed weighting factors and can improve the reproducibility of temperature measurement using 1 H MRS-based thermometry.
Collapse
Affiliation(s)
- Zhengchao Dong
- Department of Psychiatry, Columbia University College of Physicians & Surgeons, New York, New York, USA
- New York State Psychiatric Institute, New York, New York, USA
| | - Joshua T Kantrowitz
- Department of Psychiatry, Columbia University College of Physicians & Surgeons, New York, New York, USA
- New York State Psychiatric Institute, New York, New York, USA
- Nathan Kline Institute, Orangeburg, New York, USA
| | - J John Mann
- Department of Psychiatry, Columbia University College of Physicians & Surgeons, New York, New York, USA
- New York State Psychiatric Institute, New York, New York, USA
- Department of Radiology, Columbia University, College of Physicians and Surgeons, New York, New York, USA
| |
Collapse
|
6
|
Horn M, Diprose WK, Pichardo S, Demchuk A, Almekhlafi M. Non-invasive Brain Temperature Measurement in Acute Ischemic Stroke. Front Neurol 2022; 13:889214. [PMID: 35989905 PMCID: PMC9388770 DOI: 10.3389/fneur.2022.889214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
Selective therapeutic hypothermia in the setting of mechanical thrombectomy (MT) is promising to further improve the outcomes of large vessel occlusion stroke. A significant limitation in applying hypothermia in this setting is the lack of real-time non-invasive brain temperature monitoring mechanism. Non-invasive brain temperature monitoring would provide important information regarding the brain temperature changes during cooling, and the factors that might influence any fluctuations. This review aims to provide appraisal of brain temperature changes during stroke, and the currently available non-invasive modalities of brain temperature measurement that have been developed and tested over the past 20 years. We cover modalities including magnetic resonance spectroscopy imaging (MRSI), radiometric thermometry, and microwave radiometry, and the evidence for their accuracy from human and animal studies. We also evaluate the feasibility of using these modalities in the acute stroke setting and potential ways for incorporating brain temperature monitoring in the stroke workflow.
Collapse
Affiliation(s)
- MacKenzie Horn
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- *Correspondence: MacKenzie Horn
| | - William K Diprose
- Department of Medicine, University of Auckland, Auckland, New Zealand
| | - Samuel Pichardo
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
| | - Andrew Demchuk
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
| | - Mohammed Almekhlafi
- Department of Clinical Neurosciences, University of Calgary, Calgary, AB, Canada
- Department of Radiology, University of Calgary, Calgary, AB, Canada
- Department of Community Health Sciences, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
7
|
Dong Z, Milak MS, Mann JJ. Proton magnetic resonance spectroscopy thermometry: Impact of separately acquired full water or partially suppressed water data on quantification and measurement error. NMR IN BIOMEDICINE 2022; 35:e4681. [PMID: 34961997 DOI: 10.1002/nbm.4681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 11/02/2021] [Accepted: 12/20/2021] [Indexed: 06/14/2023]
Abstract
In proton magnetic resonance spectroscopy (1 H MRS) thermometry, separately acquired full water and partially suppressed water are commonly used for measuring temperature. This paper compares these two approaches. Single-voxel 1 H MRS data were collected on a 3-T GE scanner from 26 human subjects. Every subject underwent five continuous MRS sessions, each separated by a 2-min phase. Each MRS session lasted 13 min and consisted of two free induction decays (FIDs) without water suppression (with full water [FW or w]) and 64 FIDs with partial water suppression (with partially suppressed water [PW or w']). Frequency differences between the two FWs, the first two PWs, the second FW and the first PW (FW2 , PW1 ), or between averaged water ( wav' ) and N-acetylaspartate (NAA), were measured. Intrasubject and intersubject variations of the frequency differences were used as a metric for the error in temperature measurement. The intrasubject variations of frequency differences between FW2 and PW1fw2-fw1' , calculated from the five MRS sessions for each subject, were larger than those between the two FWs or between the first two PWs (p = 1.54 x 10-4 and p = 1.72 x 10-4 , respectively). The mean values of intrasubject variations of fw2-fw1' for all subjects were 4.7 and 4.5 times those of fw2-fw1 and fw2'-fw1' , respectively. The intrasubject variations of the temperatures based on frequency differences, fw2-fNAA or ( fw1'-fNAA ), were about 2.5 times greater than those based on averaged water and NAA frequencies (fwav'-fNAA ). The mean temperature measured from (fwav'-fNAA ) (n = 26) was 0.29°C lower than that measured from fw2-fNAA and was 0.83°C higher than that from ( fw1'-fNAA ). It was concluded that the use of separately acquired unsuppressed or partially suppressed water signals may result in large errors in frequency and, consequently, temperature measurement.
Collapse
Affiliation(s)
- Zhengchao Dong
- Department of Psychiatry, Columbia University, College of Physicians and Surgeons, New York, New York, USA
- Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, New York, USA
| | - Matthew S Milak
- Department of Psychiatry, Columbia University, College of Physicians and Surgeons, New York, New York, USA
- Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, New York, USA
| | - J John Mann
- Department of Psychiatry, Columbia University, College of Physicians and Surgeons, New York, New York, USA
- Molecular Imaging and Neuropathology, New York State Psychiatric Institute, New York, New York, USA
- Department of Radiology, Columbia University, College of Physicians and Surgeons, New York, New York, USA
| |
Collapse
|
8
|
Spees WM, Sukstanskii AL, Bretthorst GL, Neil JJ, Ackerman JJH. Rat Brain Global Ischemia-Induced Diffusion Changes Revisited: Biophysical Modeling of the Water and NAA MR "Diffusion Signal". Magn Reson Med 2022; 88:1333-1346. [PMID: 35452137 DOI: 10.1002/mrm.29262] [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: 10/12/2021] [Revised: 03/18/2022] [Accepted: 03/20/2022] [Indexed: 11/06/2022]
Abstract
PURPOSE To assess changes in intracellular diffusion as a mechanism for the reduction in water ADC that accompanies brain injury. Using NAA as a marker of neuronal cytoplasmic diffusion, NAA diffusion was measured before and after global ischemia (immediately postmortem) in the female Sprague-Dawley rat. METHODS Diffusion-weighted PRESS spectra, with diffusion encoding in a single direction, were acquired from large voxels of rat brain gray matter in vivo and postischemia employing either pairs of pulsed half-sine-shaped gradients (in vivo and postischemia, bmax = 19 ms/μm2 ) or sinusoidal oscillating gradients (in vivo only) with frequencies of 99.2-250 Hz. A 2D randomly oriented cylinder (neurite) model gave estimates of longitudinal and transverse diffusivities (DL and DT , respectively). In this model, DL represents the "free" diffusivity of NAA, whereas DT reflects highly restricted diffusion. Using oscillating gradients, the frequency dependence of DT [DT (ω)] gave estimates of the cylinder (axon/dendrite) radius. RESULTS A 10% decrease in DL,NAA followed global ischemia, dropping from 0.391 ± 0.012 μm2 /ms to 0.350 ± 0.009 μm2 /ms. Modeling DT,NAA (ω) provided an estimate of the neurite radius of 1.0 ± 0.6 μm. CONCLUSION Whereas the increase in apparent intraneuronal viscosity suggested by changes in DL,NAA may contribute to the overall reduction in water ADC associated with brain injury, it is not sufficient to be the sole explanation. Estimates of neurite radius based on DT (ω) were consistent with literature values.
Collapse
Affiliation(s)
- William M Spees
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Alex L Sukstanskii
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - G Larry Bretthorst
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Jeffrey J Neil
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri.,Department of Neurology, Washington University School of Medicine, St. Louis, Missouri.,Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Joseph J H Ackerman
- Biomedical MR Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri.,Department of Chemistry, Washington University, St. Louis, Missouri.,Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri.,Alvin J Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
9
|
Verma V, Lange F, Bainbridge A, Harvey-Jones K, Robertson NJ, Tachtsidis I, Mitra S. Brain temperature monitoring in newborn infants: Current methodologies and prospects. Front Pediatr 2022; 10:1008539. [PMID: 36268041 PMCID: PMC9577084 DOI: 10.3389/fped.2022.1008539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 09/15/2022] [Indexed: 02/02/2023] Open
Abstract
Brain tissue temperature is a dynamic balance between heat generation from metabolism, passive loss of energy to the environment, and thermoregulatory processes such as perfusion. Perinatal brain injuries, particularly neonatal encephalopathy, and seizures, have a significant impact on the metabolic and haemodynamic state of the developing brain, and thereby likely induce changes in brain temperature. In healthy newborn brains, brain temperature is higher than the core temperature. Magnetic resonance spectroscopy (MRS) has been used as a viable, non-invasive tool to measure temperature in the newborn brain with a reported accuracy of up to 0.2 degrees Celcius and a precision of 0.3 degrees Celcius. This measurement is based on the separation of chemical shifts between the temperature-sensitive water peaks and temperature-insensitive singlet metabolite peaks. MRS thermometry requires transport to an MRI scanner and a lengthy single-point measurement. Optical monitoring, using near infrared spectroscopy (NIRS), offers an alternative which overcomes this limitation in its ability to monitor newborn brain tissue temperature continuously at the cot side in real-time. Near infrared spectroscopy uses linear temperature-dependent changes in water absorption spectra in the near infrared range to estimate the tissue temperature. This review focuses on the currently available methodologies and their viability for accurate measurement, the potential benefits of monitoring newborn brain temperature in the neonatal intensive care unit, and the important challenges that still need to be addressed.
Collapse
Affiliation(s)
- Vinita Verma
- Institute for Women's Health, University College London, London, United Kingdom
| | - Frederic Lange
- Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Alan Bainbridge
- Medical Physics and Engineering, University College London Hospital, London, United Kingdom
| | - Kelly Harvey-Jones
- Institute for Women's Health, University College London, London, United Kingdom
| | - Nicola J Robertson
- Institute for Women's Health, University College London, London, United Kingdom
| | - Ilias Tachtsidis
- Medical Physics and Biomedical Engineering, University College London, London, United Kingdom
| | - Subhabrata Mitra
- Institute for Women's Health, University College London, London, United Kingdom
| |
Collapse
|
10
|
Brain Temperature Measured by Magnetic Resonance Spectroscopy to Predict Clinical Outcome in Patients with Infarction. SENSORS 2021; 21:s21020490. [PMID: 33445603 PMCID: PMC7827727 DOI: 10.3390/s21020490] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/06/2021] [Accepted: 01/07/2021] [Indexed: 02/01/2023]
Abstract
Acute ischemic stroke is characterized by dynamic changes in metabolism and hemodynamics, which can affect brain temperature. We used proton magnetic resonance (MR) spectroscopy under everyday clinical settings to measure brain temperature in seven patients with internal carotid artery occlusion to explore the relationship between lesion temperature and clinical course. Regions of interest were selected in the infarct area and the corresponding contralateral region. Single-voxel MR spectroscopy was performed using the following parameters: 2000-ms repetition time, 144-ms echo time, and 128 excitations. Brain temperature was calculated from the chemical shift between water and N-acetyl aspartate, choline-containing compounds, or creatine phosphate. Within 48 h of onset, compared with the contralateral region temperature, brain temperature in the ischemic lesion was lower in five patients and higher in two patients. Severe brain swelling occurred subsequently in three of the five patients with lower lesion temperatures, but in neither of the two patients with higher lesion temperatures. The use of proton MR spectroscopy to measure brain temperature in patients with internal carotid artery occlusion may predict brain swelling and subsequent motor deficits, allowing for more effective early surgical intervention. Moreover, our methodology allows for MR spectroscopy to be used in everyday clinical settings.
Collapse
|
11
|
Kohut SJ, Kaufman MJ. Magnetic resonance spectroscopy studies of substance use disorders: Current landscape and potential future directions. Pharmacol Biochem Behav 2020; 200:173090. [PMID: 33333132 DOI: 10.1016/j.pbb.2020.173090] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/13/2020] [Accepted: 12/08/2020] [Indexed: 12/25/2022]
Abstract
Over 200 in vivo magnetic resonance spectroscopy (MRS) studies of substance use and related disorders (SUD) were published this past decade. The large majority of this work used proton (1H)-MRS to characterize effects of acute and chronic exposures to drugs of abuse on human brain metabolites including N-acetylaspartate, choline-containing metabolites, creatine plus phosphocreatine, glutamate, and GABA. Some studies used phosphorus (31P)-MRS to quantify biomarkers of cerebral metabolism including phosphocreatine and adenosine triphosphate. A few studies used carbon (13C)-MRS to quantify intermediary metabolism. This Mini-review discusses select studies that illustrate how MRS can complement neurocircuitry research including by use of multimodal imaging strategies that combine MRS with functional MRI (fMRI) and/or diffusion tensor imaging (DTI). Additionally, magnetic resonance spectroscopic imaging (MRSI), which enables simultaneous multivoxel MRS acquisitions, can be used to better understand and interpret whole-brain functional or structural connectivity data. The review discusses some limitations in MRS methodology and then highlights important knowledge gaps and areas for potential future investigation, including the use of 1H- and 31P-MRS to quantify cerebral metabolism, oxidative stress, inflammation, and brain temperature, all of which are associated with SUD and all of which can influence neurocircuitry and behavior.
Collapse
Affiliation(s)
- Stephen J Kohut
- Behavioral Biology Research Program, McLean Hospital, Belmont, MA 02478, USA; McLean Imaging Center, McLean Hospital, Belmont, MA 02478, USA; Harvard Medical School, Department of Psychiatry, Belmont, MA 02478, USA
| | - Marc J Kaufman
- McLean Imaging Center, McLean Hospital, Belmont, MA 02478, USA; Harvard Medical School, Department of Psychiatry, Belmont, MA 02478, USA.
| |
Collapse
|
12
|
Annink KV, Groenendaal F, Cohen D, van der Aa NE, Alderliesten T, Dudink J, Benders MJNL, Wijnen JP. Brain temperature of infants with neonatal encephalopathy following perinatal asphyxia calculated using magnetic resonance spectroscopy. Pediatr Res 2020; 88:279-284. [PMID: 31896129 DOI: 10.1038/s41390-019-0739-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 12/10/2019] [Accepted: 12/15/2019] [Indexed: 01/20/2023]
Abstract
BACKGROUND Little is known about brain temperature of neonates during MRI. Brain temperature can be estimated non-invasively with proton Magnetic Resonance Spectroscopy (1H-MRS), but the most accurate 1H-MRS method has not yet been determined. The primary aim was to estimate brain temperature using 1H-MRS in infants with neonatal encephalopathy (NE) following perinatal asphyxia. The secondary aim was to compare brain temperature during MRI with rectal temperatures before and after MRI. METHODS In this retrospective study, brain temperature in 36 (near-)term infants with NE was estimated using short (36 ms) and long (288 ms) echo time (TE) 1H-MRS. Brain temperature was calculated using two different formulas: formula of Wu et al. and a formula based on phantom calibration. The methods were compared. Rectal temperatures were collected <3 hours before and after MRI. RESULTS Brain temperatures calculated with the formula of Wu et al. and the calibrated formula were similar as well as brain temperatures derived from short and long TE 1H-MRS. Rectal temperature did not differ before and after MRI. CONCLUSIONS Brain temperature can be measured using 1H-MRS in daily clinical practice using the formula of Wu et al. with both short and long TE 1H-MRS. Brain temperature remained within physiological range during MRI.
Collapse
Affiliation(s)
- Kim V Annink
- Department of Neonatology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Floris Groenendaal
- Department of Neonatology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Daan Cohen
- Department of Neonatology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Niek E van der Aa
- Department of Neonatology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Thomas Alderliesten
- Department of Neonatology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Jeroen Dudink
- Department of Neonatology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Manon J N L Benders
- Department of Neonatology, University Medical Center Utrecht Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Jannie P Wijnen
- Department of Radiology, University Medical Center Utrecht, University Utrecht, Utrecht, The Netherlands.
| |
Collapse
|
13
|
Zhang Y, Taub E, Mueller C, Younger J, Uswatte G, DeRamus TP, Knight DC. Reproducibility of whole-brain temperature mapping and metabolite quantification using proton magnetic resonance spectroscopy. NMR IN BIOMEDICINE 2020; 33:e4313. [PMID: 32348017 DOI: 10.1002/nbm.4313] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 03/24/2020] [Accepted: 03/25/2020] [Indexed: 06/11/2023]
Abstract
Assessing brain temperature can provide important information about disease processes (e.g., stroke, trauma) and therapeutic effects (e.g., cerebral hypothermia treatment). Whole-brain magnetic resonance spectroscopic imaging (WB-MRSI) is increasingly used to quantify brain metabolites across the entire brain. However, its feasibility and reliability for estimating brain temperature needs further validation. Therefore, the present study evaluates the reproducibility of WB-MRSI for temperature mapping as well as metabolite quantification across the whole brain in healthy volunteers. Ten healthy adults were scanned on three occasions 1 week apart. Brain temperature, along with four commonly assessed brain metabolites-total N-acetyl-aspartate (tNAA), total creatine (tCr), total choline (tCho) and myo-inositol (mI)-were measured from WB-MRSI data. Reproducibility was evaluated using the coefficient of variation (CV). The measured mean (range) of the intra-subject CVs was 0.9% (0.6%-1.6%) for brain temperature mapping, and 4.7% (2.5%-15.7%), 6.4% (2.4%-18.9%) and 14.2% (4.4%-52.6%) for tNAA, tCho and mI, respectively, with reference to tCr. Consistently larger variability was found when using H2 O as the reference for metabolite quantifications: 7.8% (3.3%-17.8%), 7.8% (3.1%-18.0%), 9.8% (3.7%-31.0%) and 17.0% (5.9%-54.0%) for tNAA, tCr, tCho and mI, respectively. Further, the larger the brain region (indicated by a greater number of voxels within that region), the better the reproducibility for both temperature and metabolite estimates. Our results demonstrate good reproducibility of whole-brain temperature and metabolite measurements using the WB-MRSI technique.
Collapse
Affiliation(s)
- Yue Zhang
- Department of Psychology, University of Alabama at Birmingham, Alabama, US
- Department of Neurosurgery and Core for Advanced MRI, Baylor College of Medicine, Houston, Texas, US
| | - Edward Taub
- Department of Psychology, University of Alabama at Birmingham, Alabama, US
| | - Christina Mueller
- Department of Psychology, University of Alabama at Birmingham, Alabama, US
| | - Jarred Younger
- Department of Psychology, University of Alabama at Birmingham, Alabama, US
| | - Gitendra Uswatte
- Department of Psychology, University of Alabama at Birmingham, Alabama, US
- Department of Physical Therapy, University of Alabama at Birmingham, Alabama, US
| | - Thomas Patrick DeRamus
- TReNDs Center for Translational Research in Neuroimaging and Data Science, Georgia, US
- Department of Psychology, Georgia State University, Georgia, US
| | - David C Knight
- Department of Psychology, University of Alabama at Birmingham, Alabama, US
| |
Collapse
|
14
|
Wu TW, Wisnowski JL, Geisler RF, Reitman A, Ho E, Tamrazi B, Chapman R, Blüml S. An In Vivo Assessment of Regional Brain Temperature during Whole-Body Cooling for Neonatal Encephalopathy. J Pediatr 2020; 220:73-79.e3. [PMID: 32089332 PMCID: PMC7265905 DOI: 10.1016/j.jpeds.2020.01.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 12/05/2019] [Accepted: 01/10/2020] [Indexed: 12/25/2022]
Abstract
OBJECTIVE To assess differences in regional brain temperatures during whole-body hypothermia and test the hypothesis that brain temperature profile is nonhomogenous in infants with hypoxic-ischemic encephalopathy. STUDY DESIGN Infants with hypoxic-ischemic encephalopathy were enrolled prospectively in this observational study. Magnetic resonance (MR) spectra of basal ganglia, thalamus, cortical gray matter, and white matter (WM) were acquired during therapeutic hypothermia. Regional brain tissue temperatures were calculated from the chemical shift difference between water signal and metabolites in the MR spectra after performing calibration measurements. Overall difference in regional temperature was analyzed by mixed-effects model; temperature among different patterns and severity of injury on MR imaging also was analyzed. Correlation between temperature and depth of brain structure was analyzed using repeated-measures correlation. RESULTS In total, 53 infants were enrolled (31 girls, mean gestational age: 38.6 ± 2 weeks; mean birth weight: 3243 ± 613 g). MR spectroscopy was acquired at mean age of 2.2 ± 0.6 days. A total of 201 MR spectra were included in the analysis. The thalamus, the deepest structure (36.4 ± 2.3 mm from skull surface), was lowest in temperature (33.2 ± 0.8°C, compared with basal ganglia: 33.5 ± 0.9°C; gray matter: 33.6 ± 0.7°C; WM: 33.8 ± 0.9°C, all P < .001). Temperatures in more superficial gray matter and WM regions (depth: 21.9 ± 2.4 and 21.5 ± 2.2 mm) were greater than the rectal temperatures (33.4 ± 0.4°C, P < .03). There was a negative correlation between temperature and depth of brain structure (rrm = -0.36, P < .001). CONCLUSIONS Whole-body hypothermia was effective in cooling deep brain structures, whereas superficial structures were warmer, with temperatures significantly greater than rectal temperatures.
Collapse
Affiliation(s)
- Tai-Wei Wu
- Fetal and Neonatal Institute, Division of Neonatology, Children's Hospital Los Angeles, Los Angeles, CA; Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA.
| | - Jessica L. Wisnowski
- Department of Radiology, Children’s Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA;,Rudi Schulte Research Institute, Santa Barbara, CA
| | - Robert F. Geisler
- Division of Neonatology, Children’s Hospital, Fetal and Neonatal Institute, Los Angeles
| | - Aaron Reitman
- Division of Neonatology, Children’s Hospital, Fetal and Neonatal Institute, Los Angeles
| | - Eugenia Ho
- Division of Neurology, Children’s Hospital Los Angeles, Los Angeles, CA
| | - Benita Tamrazi
- Department of Radiology, Children’s Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA
| | - Rachel Chapman
- Division of Neonatology, Children’s Hospital, Fetal and Neonatal Institute, Los Angeles;,Department of Pediatrics, Keck School of Medicine, University of Southern California
| | - Stefan Blüml
- Department of Radiology, Children’s Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA;,Rudi Schulte Research Institute, Santa Barbara, CA
| |
Collapse
|
15
|
Antonacci MA, McHugh C, Kelley M, McCallister A, Degan S, Branca RT. Direct detection of brown adipose tissue thermogenesis in UCP1-/- mice by hyperpolarized 129Xe MR thermometry. Sci Rep 2019; 9:14865. [PMID: 31619741 PMCID: PMC6795875 DOI: 10.1038/s41598-019-51483-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 10/02/2019] [Indexed: 12/19/2022] Open
Abstract
Brown adipose tissue (BAT) is a type of fat specialized in non-shivering thermogenesis. While non-shivering thermogenesis is mediated primarily by uncoupling protein 1 (UCP1), the development of the UCP1 knockout mouse has enabled the study of possible UCP1-independent non-shivering thermogenic mechanisms, whose existence has been shown so far only indirectly in white adipose tissue and still continues to be a matter of debate in BAT. In this study, by using magnetic resonance thermometry with hyperpolarized xenon, we produce the first direct evidence of UCP1-independent BAT thermogenesis in knockout mice. We found that, following adrenergic stimulation, the BAT temperature of knockout mice increases more and faster than rectal temperature. While with this study we cannot exclude or separate the physiological effect of norepinephrine on core body temperature, the fast increase of iBAT temperature seems to suggest the existence of a possible UCP1-independent thermogenic mechanism responsible for this temperature increase.
Collapse
Affiliation(s)
- Michael A Antonacci
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Physics, Saint Vincent College, Latrobe, Pennsylvania, United States of America
| | - Christian McHugh
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Michele Kelley
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Andrew McCallister
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Simone Degan
- Department of Radiology, Duke University, Durham, North Carolina, United States of America
| | - Rosa T Branca
- Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
- Biomedical Research Imaging Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
| |
Collapse
|
16
|
Mintzopoulos D, Ratai EM, He J, Gonzalez RG, Kaufman MJ. Simian immunodeficiency virus transiently increases brain temperature in rhesus monkeys: detection with magnetic resonance spectroscopy thermometry. Magn Reson Med 2019; 81:2896-2904. [PMID: 30652349 DOI: 10.1002/mrm.27635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 11/19/2018] [Accepted: 11/20/2018] [Indexed: 01/14/2023]
Abstract
PURPOSE To evaluate brain temperature effects of early simian immunodeficiency virus (SIV) infection in rhesus macaques using proton magnetic resonance spectroscopy (MRS) thermometry (MRSt) and to determine whether temperature correlates with brain choline or myo-inositol levels. METHODS Brain temperature was retrospectively determined in serial MRS scans that had been acquired at baseline and at 2 and 4 weeks post-SIV infection (wpi) in 16 monkeys by calculating the chemical shift difference between N-acetylaspartate (NAA) and water peaks in sequentially acquired water-suppressed and unsuppressed point-resolved spectroscopy (PRESS) spectra. Frontal and parietal cortex, basal ganglia, and white matter spectra were analyzed. RESULTS At 2 wpi, brain and rectal temperatures increased relative to baseline and normalized at 4 wpi. Brain temperatures correlated with choline levels in several brain areas, but not with myo-inositol levels. CONCLUSION These data indicate that SIV transiently increases brain temperature soon after infection and that temperature is correlated with transient changes in choline levels. Given that choline levels are associated with brain inflammation in SIV-infected monkeys, our findings suggest that the SIV-induced temperature increase reflects brain inflammation. We conclude that MRSt may be informative in human immunodeficiency virus models and may be useful for assessing effects of treatments that reduce inflammation. This study also illustrates that existing MRS data sets containing unsuppressed water spectra can be used to measure tissue temperature, an important physiological parameter.
Collapse
Affiliation(s)
- Dionyssios Mintzopoulos
- McLean Imaging Center, McLean Hospital, Belmont, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Eva-Maria Ratai
- A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Julian He
- A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Ramon Gilberto Gonzalez
- A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Marc J Kaufman
- McLean Imaging Center, McLean Hospital, Belmont, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| |
Collapse
|
17
|
Verius M, Frank F, Gizewski E, Broessner G. Magnetic Resonance Spectroscopy Thermometry at 3 Tesla: Importance of Calibration Measurements. Ther Hypothermia Temp Manag 2018; 9:146-155. [PMID: 30457932 DOI: 10.1089/ther.2018.0027] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
To demonstrate the importance of calibration measurements in 3 Tesla proton magnetic resonance (MR) spectroscopy (1H-MRS) thermometry for human brain temperature estimation for routine clinical applications. In vitro proton MR spectroscopy to obtain calibration constants of the water-chemical shift was conducted at 3 Tesla with a temperature-controlled phantom, containing a pH-buffered aqueous solution of N-acetyl aspartate (NAA), creatine (Cr), methylene protons of Cr (Cr2), dimethyl silapentane sulfonic acid (DSS), and sodium formate (NaFor). Estimations of absolute human brain temperature were performed utilizing the correlation of temperature to the water-chemical shift for the resonances of NAA, Cr, and Cr2. Data for calibration of the metabolites' chemical shift differences and in vivo temperature estimations were acquired with single-voxel point-resolved spectroscopy (PRESS) sequences (repetition time/echo time = 2000/30 ms; voxel size 2 × 2 × 2 cm3). Spectroscopy data were quantified in the time-domain, and a Pearson correlation analysis was performed to estimate the correlation between the chemical shift of metabolites and measured temperatures. The correlation coefficients (r) of our calibration measurements were NAA 0.9975 (±0.0609), Cr -0.9979 (±0.0621), Cr2 - 0.9973 (±0.0577), DSS -0.9976 (±0.0615), and NaFor -0.8132 (±2.348). The mean calculated brain temperature was 37.78 ± 1.447°C, and the mean tympanic temperature was 36.83 ± 0.2456°C. Calculated temperatures derived from Cr and Cr2 provided significant (p = 0.0241 and p = 0.0210, respectively) correlations with measured temperatures (r = 0.4108 and r = -0.4194, respectively). Calibration measurements are vital for 1H-MRS thermometry. Small numeric differences in measured signal and data preprocessing without any calibration measurements reduce accuracy of temperature calculations, which indicates that calculated temperatures should be interpreted with caution. Application of this method for clinical purposes warrants further investigation and a more practical approach.
Collapse
Affiliation(s)
- Michael Verius
- 1 Medizinische Universität Innsbruck, Neuroimaging Research Core Facility, Innsbruck, Austria
| | - Florian Frank
- 2 Medizinische Universität Innsbruck, Universitätsklinik für Neurologie, Innsbruck, Austria
| | - Elke Gizewski
- 1 Medizinische Universität Innsbruck, Neuroimaging Research Core Facility, Innsbruck, Austria.,3 Medizinische Universität Innsbruck, Universitätsklinik für Neuroradiologie, Innsbruck, Austria
| | - Gregor Broessner
- 2 Medizinische Universität Innsbruck, Universitätsklinik für Neurologie, Innsbruck, Austria
| |
Collapse
|
18
|
McLaughlin JP, Paris JJ, Mintzopoulos D, Hymel KA, Kim JK, Cirino TJ, Gillis TE, Eans SO, Vitaliano GD, Medina JM, Krapf RC, Stacy HM, Kaufman MJ. Conditional Human Immunodeficiency Virus Transactivator of Transcription Protein Expression Induces Depression-like Effects and Oxidative Stress. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2017; 2:599-609. [PMID: 29057370 PMCID: PMC5648358 DOI: 10.1016/j.bpsc.2017.04.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND The prevalence of major depression in those with HIV/AIDS is substantially higher than in the general population. Mechanisms underlying this comorbidity are poorly understood. HIV-transactivator of transcription (Tat) protein, produced and excreted by HIV, could be involved. We determined whether conditional Tat protein expression in mice is sufficient to induce depression-like behaviors and oxidative stress. Further, as oxidative stress is associated with depression, we determined whether decreasing or increasing oxidative stress by administering methylsulfonylmethane (MSM) or diethylmaleate (DEM), respectively, altered depression-like behavior. METHODS GT-tg bigenic mice received intraperitoneal saline or doxycycline (Dox, 25-100 mg/kg/day) to induce Tat expression. G-tg mice, which do not express Tat protein, also received Dox. Depression-like behavior was assessed with the tail suspension test (TST) and the two-bottle saccharin/water consumption task. Reactive oxygen/nitrogen species (ROS/RNS) were assessed ex vivo. Medial frontal cortex (MFC) oxidative stress and temperature were measured in vivo with 9.4-Tesla proton magnetic resonance spectroscopy (MRS). RESULTS Tat expression increased TST immobility time in an exposure-dependent manner and reduced saccharin consumption. MSM decreased immobility time while DEM increased it in saline-treated GT-tg mice. Tat and MSM behavioral effects persisted for 28 days. Tat and DEM increased while MSM decreased ROS/RNS levels. Tat expression increased MFC glutathione levels and temperature. CONCLUSIONS Tat expression induced rapid and enduring depression-like behaviors and oxidative stress. Increasing/decreasing oxidative stress increased/decreased, respectively, depression-like behavior. Thus, Tat produced by HIV may contribute to the high depression prevalence among those with HIV. Further, mitigation of oxidative stress could reduce depression severity.
Collapse
Affiliation(s)
- Jay P. McLaughlin
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610
| | - Jason J. Paris
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610
- Virginia Commonwealth University, Department of Pharmacology & Toxicology, Richmond, VA 23298
| | - Dionyssios Mintzopoulos
- McLean Imaging Center, Department of Psychiatry, McLean Hospital/Harvard Medical School, Belmont, MA 02478
| | - Kristen A. Hymel
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610
| | - Jae K. Kim
- McLean Imaging Center, Department of Psychiatry, McLean Hospital/Harvard Medical School, Belmont, MA 02478
| | - Thomas J. Cirino
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610
| | - Timothy E. Gillis
- McLean Imaging Center, Department of Psychiatry, McLean Hospital/Harvard Medical School, Belmont, MA 02478
| | - Shainnel O. Eans
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610
| | - Gordana D. Vitaliano
- McLean Imaging Center, Department of Psychiatry, McLean Hospital/Harvard Medical School, Belmont, MA 02478
| | - Jessica M. Medina
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610
| | - Richard C. Krapf
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610
| | - Heather M. Stacy
- Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, FL 32610
| | - Marc J. Kaufman
- McLean Imaging Center, Department of Psychiatry, McLean Hospital/Harvard Medical School, Belmont, MA 02478
| |
Collapse
|
19
|
Abstract
Thermal ablation techniques such as radiofrequency, microwave, high intensity focused ultrasound (HIFU) and laser have been used as minimally invasive strategies for the treatment of variety of cancers. MR thermometry methods are readily available for monitoring thermal distribution and deposition in real time, leading to decrease of incidents of normal tissue damage around targeted lesion. HIFU and laser-induced thermal therapy (LITT) are the two widely accepted tumor ablation techniques because of their compatibility with MR systems. MRI provides multiple temperature dependent parameters for thermal imaging, such as signal intensity, T1, T2, diffusion coefficient, magnetization transfer, proton resonance frequency shift (PRFS, including phase imaging and spectroscopy) as well as frequency shift of temperature sensitive contrast agents. Absolute temperature mapping techniques, including both spectroscopic imaging using metabolites as a reference and phase imaging using fat as a reference, are immune to susceptibility effects and are not dependent on phase differences. These techniques are intrinsically more reliable than relative temperature measurement by phase mapping methods. If the limitation of low temporal and spatial resolution could be overcome, these methods may be preferred for MR-guided thermal ablation systems. As of today, the most popular MR thermal imaging method applied in tumor thermal ablation surgery is, however, still PRFS based phase mapping technique, which only provides relative temperature change and is prone to motion artifacts.
Collapse
Affiliation(s)
- Mingming Zhu
- Department of Radiology, School of Medicine, University of Louisville, Louisville, KY, USA
| | - Ziqi Sun
- Department of Radiology, School of Medicine, University of Louisville, Louisville, KY, USA
| | - Chin K Ng
- Department of Radiology, School of Medicine, University of Louisville, Louisville, KY, USA
| |
Collapse
|
20
|
Maudsley AA, Goryawala MZ, Sheriff S. Effects of tissue susceptibility on brain temperature mapping. Neuroimage 2016; 146:1093-1101. [PMID: 27693198 DOI: 10.1016/j.neuroimage.2016.09.062] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 09/15/2016] [Accepted: 09/26/2016] [Indexed: 02/07/2023] Open
Abstract
A method for mapping of temperature over a large volume of the brain using volumetric proton MR spectroscopic imaging has been implemented and applied to 150 normal subjects. Magnetic susceptibility-induced frequency shifts in gray- and white-matter regions were measured and included as a correction in the temperature mapping calculation. Additional sources of magnetic susceptibility variations of the individual metabolite resonance frequencies were also observed that reflect the cellular-level organization of the brain metabolites, with the most notable differences being attributed to changes of the N-Acetylaspartate resonance frequency that reflect the intra-axonal distribution and orientation of the white-matter tracts with respect to the applied magnetic field. These metabolite-specific susceptibility effects are also shown to change with age. Results indicate no change of apparent brain temperature with age from 18 to 84 years old, with a trend for increased brain temperature throughout the cerebrum in females relative for males on the order of 0.1°C; slightly increased temperatures in the left hemisphere relative to the right; and a lower temperature of 0.3°C in the cerebellum relative to that of cerebral white-matter. This study presents a novel acquisition method for noninvasive measurement of brain temperature that is of potential value for diagnostic purposes and treatment monitoring, while also demonstrating limitations of the measurement due to the confounding effects of tissue susceptibility variations.
Collapse
|
21
|
Vieites-Prado A, Iglesias-Rey R, Fernández-Susavila H, da Silva-Candal A, Rodríguez-Castro E, Gröhn OHJ, Wellmann S, Sobrino T, Castillo J, Campos F. Protective Effects and Magnetic Resonance Imaging Temperature Mapping of Systemic and Focal Hypothermia in Cerebral Ischemia. Stroke 2016; 47:2386-96. [PMID: 27491739 DOI: 10.1161/strokeaha.116.014067] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 06/30/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Hypothermia is potentially the most effective protective therapy for brain ischemia; however, its use is limited because of serious side effects. Although focal hypothermia (FH) has a significantly lower stress profile than systemic hypothermia (SH), its efficacy in ischemia has been poorly studied. We aimed to compare the therapeutic effects of each treatment on various short- and long-term clinically relevant end points. METHODS Sprague-Dawley rats were subjected to transient (45 minutes) occlusion of the middle cerebral artery. One hour after arterial reperfusion, animals were randomly assigned to groups for treatment with SH or FH (target temperature: 32°C) for 4 or 24 hours. Lesion volume, edema, functional recovery, and histological markers of cellular injury were evaluated for 1 month after ischemic injury. Effects of SH and FH on cerebral temperature were also analyzed for the first time by magnetic resonance thermometry, an approach that combines spectroscopy with gradient-echo-based phase mapping. RESULTS Both therapeutic approaches reduced ischemic lesion volume (P<0.001), although a longer FH treatment (24 hours) was required to achieve similar protective effects to those induced by 4 hours of SH. In addition, magnetic resonance thermometry demonstrated that systemic hypothermia reduced whole-brain temperature, whereas FH primarily reduced the temperature of the ischemic region. CONCLUSIONS Focal brain hypothermia requires longer cooling periods to achieve the same protective efficacy as SH. However, FH mainly affects the ischemic region, and therefore represents a promising and nonstressful alternative to SH.
Collapse
Affiliation(s)
- Alba Vieites-Prado
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.)
| | - Ramón Iglesias-Rey
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.)
| | - Héctor Fernández-Susavila
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.)
| | - Andrés da Silva-Candal
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.)
| | - Emilio Rodríguez-Castro
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.)
| | - Olli H J Gröhn
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.)
| | - Sven Wellmann
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.)
| | - Tomás Sobrino
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.)
| | - José Castillo
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.).
| | - Francisco Campos
- From the Clinical Neurosciences Research Laboratory, Clinical University Hospital, Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, Spain (A.V.-P., R.I.-R., H.F.-S., A.d.S.-C., E.R.-C., T.S., J.C., F.C.); Department of Neurobiology, AI Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio (O.H.J.G.); and Division of Neonatology, University of Basel Children's Hospital (UKBB), Switzerland (S.W.).
| |
Collapse
|
22
|
Hartmann J, Gellermann J, Brandt T, Schmidt M, Pyatykh S, Hesser J, Ott O, Fietkau R, Bert C. Optimization of Single Voxel MR Spectroscopy Sequence Parameters and Data Analysis Methods for Thermometry in Deep Hyperthermia Treatments. Technol Cancer Res Treat 2016; 16:470-481. [PMID: 27422012 DOI: 10.1177/1533034616656310] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE The difference in the resonance frequency of water and methylene moieties of lipids quantifies in magnetic resonance spectroscopy the absolute temperature using a predefined calibration curve. The purpose of this study was the investigation of peak evaluation methods and the magnetic resonance spectroscopy sequence (point-resolved spectroscopy) parameter optimization that enables thermometry during deep hyperthermia treatments. MATERIALS AND METHODS Different Lorentz peak-fitting methods and a peak finding method using singular value decomposition of a Hankel matrix were compared. Phantom measurements on organic substances (mayonnaise and pork) were performed inside the hyperthermia 1.5-T magnetic resonance imaging system for the parameter optimization study. Parameter settings such as voxel size, echo time, and flip angle were varied and investigated. RESULTS Usually all peak analyzing methods were applicable. Lorentz peak-fitting method in MATLAB proved to be the most stable regardless of the number of fitted peaks, yet the slowest method. The examinations yielded an optimal parameter combination of 8 cm3 voxel volume, 55 millisecond echo time, and a 90° excitation pulse flip angle. CONCLUSION The Lorentz peak-fitting method in MATLAB was the most reliable peak analyzing method. Measurements in homogeneous and heterogeneous phantoms resulted in optimized parameters for the magnetic resonance spectroscopy sequence for thermometry.
Collapse
Affiliation(s)
- J Hartmann
- 1 Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - J Gellermann
- 2 Department of Radiation Oncology, University Hospital Tübingen, Tübingen, Germany.,3 Praxis/Zentrum für Strahlentherapie und Radioonkologie, Berlin, Germany
| | - T Brandt
- 1 Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - M Schmidt
- 1 Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - S Pyatykh
- 4 Medical Faculty Mannheim, Experimental Radiation Oncology, Heidelberg University, Mannheim, Germany
| | - J Hesser
- 4 Medical Faculty Mannheim, Experimental Radiation Oncology, Heidelberg University, Mannheim, Germany
| | - O Ott
- 1 Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - R Fietkau
- 1 Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - C Bert
- 1 Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| |
Collapse
|
23
|
Babourina-Brooks B, Simpson R, Arvanitis TN, Machin G, Peet AC, Davies NP. MRS thermometry calibration at 3 T: effects of protein, ionic concentration and magnetic field strength. NMR IN BIOMEDICINE 2015; 28:792-800. [PMID: 25943246 DOI: 10.1002/nbm.3303] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 03/12/2015] [Accepted: 03/13/2015] [Indexed: 06/04/2023]
Abstract
MRS thermometry has been utilized to measure temperature changes in the brain, which may aid in the diagnosis of brain trauma and tumours. However, the temperature calibration of the technique has been shown to be sensitive to non-temperature-based factors, which may provide unique information on the tissue microenvironment if the mechanisms can be further understood. The focus of this study was to investigate the effects of varied protein content on the calibration of MRS thermometry at 3 T, which has not been thoroughly explored in the literature. The effects of ionic concentration and magnetic field strength were also considered. Temperature reference materials were controlled by water circulation and freezing organic fixed-point compounds (diphenyl ether and ethylene carbonate) stable to within 0.2 °C. The temperature was measured throughout the scan time with a fluoro-optic probe, with an uncertainty of 0.16 °C. The probe was calibrated at the National Physical Laboratory (NPL) with traceability to the International Temperature Scale 1990 (ITS-90). MRS thermometry measures were based on single-voxel spectroscopy chemical shift differences between water and N-acetylaspartate (NAA), Δ(H20-NAA), using a Philips Achieva 3 T scanner. Six different phantom solutions with varying protein or ionic concentration, simulating potential tissue differences, were investigated within a temperature range of 21-42 °C. Results were compared with a similar study performed at 1.5 T to observe the effect of field strengths. Temperature calibration curves were plotted to convert Δ(H20-NAA) to apparent temperature. The apparent temperature changed by -0.2 °C/% of bovine serum albumin (BSA) and a trend of 0.5 °C/50 mM ionic concentration was observed. Differences in the calibration coefficients for the 10% BSA solution were seen in this study at 3 T compared with a study at 1.5 T. MRS thermometry may be utilized to measure temperature and the tissue microenvironment, which could provide unique unexplored information for brain abnormalities and other pathologies.
Collapse
Affiliation(s)
- Ben Babourina-Brooks
- School of Cancer Sciences, University of Birmingham, Birmingham, West Midlands, UK
- Birmingham Children's Hospital NHS Foundation Trust, Birmingham, West Midlands, UK
| | - Robert Simpson
- Temperature Group, National Physical Laboratory, Teddington, Middlesex, UK
| | - Theodoros N Arvanitis
- Birmingham Children's Hospital NHS Foundation Trust, Birmingham, West Midlands, UK
- Institute of Digital Healthcare, WMG, University of Warwick, Coventry, UK
| | - Graham Machin
- Temperature Group, National Physical Laboratory, Teddington, Middlesex, UK
| | - Andrew C Peet
- School of Cancer Sciences, University of Birmingham, Birmingham, West Midlands, UK
- Birmingham Children's Hospital NHS Foundation Trust, Birmingham, West Midlands, UK
| | - Nigel P Davies
- School of Cancer Sciences, University of Birmingham, Birmingham, West Midlands, UK
- Imaging and Medical Physics, University Hospitals Birmingham NHS Foundation Trust, Birmingham, West Midlands, UK
| |
Collapse
|
24
|
Rango M, Bonifati C, Bresolin N. Post-Activation Brain Warming: A 1-H MRS Thermometry Study. PLoS One 2015; 10:e0127314. [PMID: 26011731 PMCID: PMC4444346 DOI: 10.1371/journal.pone.0127314] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 04/14/2015] [Indexed: 11/24/2022] Open
Abstract
Purpose Temperature plays a fundamental role for the proper functioning of the brain. However, there are only fragmentary data on brain temperature (Tbr) and its regulation under different physiological conditions. Methods We studied Tbr in the visual cortex of 20 normal subjects serially with a wide temporal window under different states including rest, activation and recovery by a visual stimulation-Magnetic Resonance Spectroscopy Thermometry combined approach. We also studied Tbr in a control region, the centrum semiovale, under the same conditions. Results Visual cortex mean baseline Tbr was higher than mean body temperature (37.38 vs 36.60, P<0.001). During activation Tbr remained unchanged at first and then showed a small decrease (-0.20 C°) around the baseline value. After the end of activation Tbr increased consistently (+0.60 C°) and then returned to baseline values after some minutes. Centrum semiovale Tbr remained unchanged through rest, visual stimulation and recovery. Conclusion These findings have several implications, among them that neuronal firing itself is not a major source of heat release in the brain and that there is an aftermath of brain activation that lasts minutes before returning to baseline conditions.
Collapse
Affiliation(s)
- Mario Rango
- Department of Neurological Sciences, IRCCS Ca’ Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
- Magnetic Resonance Spectroscopy Center, IRCCS Ca’ Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
- * E-mail:
| | - Cristiana Bonifati
- Department of Neurological Sciences, IRCCS Ca’ Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
- Magnetic Resonance Spectroscopy Center, IRCCS Ca’ Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| | - Nereo Bresolin
- Department of Neurological Sciences, IRCCS Ca’ Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
- Magnetic Resonance Spectroscopy Center, IRCCS Ca’ Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| |
Collapse
|
25
|
Babourina-Brooks B, Wilson M, Arvanitis TN, Peet AC, Davies NP. MRS water resonance frequency in childhood brain tumours: a novel potential biomarker of temperature and tumour environment. NMR IN BIOMEDICINE 2014; 27:1222-9. [PMID: 25125325 PMCID: PMC4491353 DOI: 10.1002/nbm.3177] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 06/13/2014] [Accepted: 07/10/2014] [Indexed: 06/03/2023]
Abstract
(1)H MRS thermometry has been investigated for brain trauma and hypothermia monitoring applications but has not been explored in brain tumours. The proton resonance frequency (PRF) of water is dependent on temperature but is also influenced by microenvironment factors, such as fast proton exchange with macromolecules, ionic concentration and magnetic susceptibility. (1)H MRS has been utilized for brain tumour diagnostic and prognostic purposes in children; however, the water PRF measure may provide complementary information to further improve characterization. Water PRF values were investigated from a repository of MRS data acquired from childhood brain tumours and children with apparently normal brains. The cohort consisted of histologically proven glioma (22), medulloblastoma (19) and control groups (28, MRS in both the basal ganglia and parietal white matter regions). All data were acquired at 1.5 T using a short TE (30 ms) single voxel spectroscopy (PRESS) protocol. Water PRF values were calculated using methyl creatine and total choline. Spectral peak amplitude weighted averaging was used to improve the accuracy of the measurements. Mean PRF values were significantly larger for medulloblastoma compared with glioma, with a difference in the means of 0.0147 ppm (p < 0.05), while the mean PRF for glioma was significantly lower than for the healthy cohort, with a difference in the means of 0.0061 ppm (p < 0.05). This would suggest the apparent temperature of the glioma group was ~1.5 °C higher than the medulloblastomas and ~0.7 °C higher than a healthy brain. However, the PRF shift may not reflect a change in temperature, given that alterations in protein content, microstructure and ionic concentration contribute to PRF shifts. Measurement of these effects could also be used as a supplementary biomarker, and further investigation is required. This study has shown that the water PRF value has the potential to be used for characterizing childhood brain tumours, which has not been reported previously.
Collapse
Affiliation(s)
- Ben Babourina-Brooks
- School of Cancer Sciences, University of BirminghamBirmingham, West Midlands, UK
- Children's Hospital NHS Foundation TrustBirmingham, West Midlands, UK
| | - Martin Wilson
- School of Cancer Sciences, University of BirminghamBirmingham, West Midlands, UK
- Children's Hospital NHS Foundation TrustBirmingham, West Midlands, UK
| | - Theodoros N Arvanitis
- Children's Hospital NHS Foundation TrustBirmingham, West Midlands, UK
- Institute of Digital Healthcare, WMG, University of WarwickCoventry, UK
| | - Andrew C Peet
- School of Cancer Sciences, University of BirminghamBirmingham, West Midlands, UK
- Children's Hospital NHS Foundation TrustBirmingham, West Midlands, UK
| | - Nigel P Davies
- School of Cancer Sciences, University of BirminghamBirmingham, West Midlands, UK
- Imaging and Medical Physics, University Hospitals Birmingham NHS Foundation TrustBirmingham, West Midlands, UK
| |
Collapse
|
26
|
Chung YH, Hsu PH, Huang CW, Hsieh WC, Huang FT, Chang WC, Chiu H, Hsu ST, Yen TC. Evaluation of Prognostic Integrin α2β1 PET Tracer and Concurrent Targeting Delivery Using Focused Ultrasound for Brain Glioma Detection. Mol Pharm 2014; 11:3904-14. [DOI: 10.1021/mp500296n] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Yi-Hsiu Chung
- Center
for Advanced Molecular Imaging and Translation (CAMIT), Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Po-Hung Hsu
- Center
for Advanced Molecular Imaging and Translation (CAMIT), Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
- Department
of Electrical Engineering, Chang Gung University, Taoyuan 333, Taiwan
| | - Chiun-Wei Huang
- Center
for Advanced Molecular Imaging and Translation (CAMIT), Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Wen-Chuan Hsieh
- Center
for Advanced Molecular Imaging and Translation (CAMIT), Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Feng-Ting Huang
- Department
of Biochemical Science and Technology, College of Life Science, National Taiwan University, Taipei, Taiwan
| | - Wen-Chi Chang
- Center
for Advanced Molecular Imaging and Translation (CAMIT), Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Han Chiu
- Center
for Advanced Molecular Imaging and Translation (CAMIT), Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Shih-Ting Hsu
- Center
for Advanced Molecular Imaging and Translation (CAMIT), Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| | - Tzu-Chen Yen
- Center
for Advanced Molecular Imaging and Translation (CAMIT), Chang Gung Memorial Hospital, Taoyuan 333, Taiwan
| |
Collapse
|
27
|
Anosov AA, Balashov IS, Beljaev RV, Vilkov VA, Garskov RV, Kazanskij AS, Mansfel’d AD, Shcherbakov MI. Acoustic thermometry of the patient brain with traumatic brain injury. Biophysics (Nagoya-shi) 2014. [DOI: 10.1134/s0006350914030026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
28
|
Rango M, Arighi A, Bonifati C, Del Bo R, Comi G, Bresolin N. The brain is hypothermic in patients with mitochondrial diseases. J Cereb Blood Flow Metab 2014; 34:915-20. [PMID: 24619278 PMCID: PMC4013774 DOI: 10.1038/jcbfm.2014.38] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 12/27/2013] [Accepted: 01/19/2014] [Indexed: 02/01/2023]
Abstract
We sought to study brain temperature in patients with mitochondrial diseases in different functional states compared with healthy participants. Brain temperature and mitochondrial function were monitored in the visual cortex and the centrum semiovale at rest and during and after visual stimulation in seven individuals with mitochondrial diseases (n=5 with mitochondrial DNA mutations and n=2 with nuclear DNA mutations) and in 14 age- and sex-matched healthy control participants using a combined approach of visual stimulation, proton magnetic resonance spectroscopy (MRS), and phosphorus MRS. Brain temperature in control participants exhibited small changes during visual stimulation and a consistent increase, together with an increase in high-energy phosphate content, after visual stimulation. Brain temperature was persistently lower in individuals with mitochondrial diseases than in healthy participants at rest, during activation, and during recovery, without significant changes from one state to another and with a decrease in the high-energy phosphate content. The lowest brain temperature was observed in the patient with the most deranged mitochondrial function. In patients with mitochondrial diseases, the brain is hypothermic because of malfunctioning oxidative phosphorylation. Neuronal activity is reduced at rest, during physiologic brain stimulation, and after stimulation.
Collapse
Affiliation(s)
- Mario Rango
- 1] Department of Neurological Sciences, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy [2] Magnetic Resonance Spectroscopy Center, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| | - Andrea Arighi
- 1] Department of Neurological Sciences, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy [2] Magnetic Resonance Spectroscopy Center, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| | - Cristiana Bonifati
- 1] Department of Neurological Sciences, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy [2] Magnetic Resonance Spectroscopy Center, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| | - Roberto Del Bo
- Department of Neurological Sciences, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| | - Giacomo Comi
- Department of Neurological Sciences, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| | - Nereo Bresolin
- 1] Department of Neurological Sciences, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy [2] Magnetic Resonance Spectroscopy Center, IRCCS Ca' Granda-Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| |
Collapse
|
29
|
Bainbridge A, Kendall GS, De Vita E, Hagmann C, Kapetanakis A, Cady EB, Robertson NJ. Regional neonatal brain absolute thermometry by 1H MRS. NMR IN BIOMEDICINE 2013; 26:416-423. [PMID: 23074155 DOI: 10.1002/nbm.2879] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/28/2012] [Accepted: 09/04/2012] [Indexed: 06/01/2023]
Abstract
Therapeutic hypothermia is standard care for infants with moderate to severe encephalopathy. (1) H MRS thermometry (MRSt) measures regional brain absolute temperature using the temperature-dependent water chemical shift. This study evaluates the clinical feasibility of MRSt in human neonates, and correlates white matter (WM) and thalamus (Thal) MRSt with conventional rectal temperature (Trectal ) measurement. Fifty-six infants born at term underwent perinatal MRSt for suspected hypoxic-ischaemic brain injury and 33 infants born preterm had MRSt at a term-equivalent age; 56 of the 89 had Trectal measured after MRSt of either a Thal or posterior WM voxel, or both. MRSt used point-resolved spectroscopy (no water suppression; TR = 1370 ms; TE = 288 ms; 1.5 × 1.5 × 1.5 cm(3) Thal and 1.1 × 1.3 × 1.4 cm(3) WM voxels). Time domain data were phase and frequency corrected before summation and motion-corrupted data were excluded from further analysis using simple criteria [preprocessing + quality assurance (QA)]. Two published water temperature-dependence calibrations [both using cerebral creatine (Cr), choline (Cho) and N-acetylaspartate (Naa) as independent reference peaks] were compared. The temperature measurements derived from Cr, Cho and Naa were combined to give a single amplitude-weighted combination temperature (TAWC ). WM and Thal TAWC correlated linearly with Trectal (Thal slope, 0.82 ± 0.04, R(2) = 0.85, p < 0.05; WM slope, 0.95 ± 0.04, R(2) = 0.78, p < 0.05). Preprocessing + QA improved the correlation between WM TAWC and Trectal (R(2) increased from 0.27 to 0.78, p < 0.001). Both calibration datasets showed specific inconsistencies between the temperatures calculated using Cr, Cho and Naa reference peaks when applied to this neonatal dataset. Neonatal MRSt is clinically feasible. Preprocessing + QA improved MRSt reliability in WM. The consideration of MRSt calibration internal biases is necessary before combining MRSt temperatures from multiple reference peaks to obtain TAWC.
Collapse
Affiliation(s)
- Alan Bainbridge
- Medical Physics and Bioengineering, University College London Hospitals NHS Foundation Trust, London, UK
| | | | | | | | | | | | | |
Collapse
|
30
|
Vescovo E, Levick A, Childs C, Machin G, Zhao S, Williams SR. High-precision calibration of MRS thermometry using validated temperature standards: effects of ionic strength and protein content on the calibration. NMR IN BIOMEDICINE 2013; 26:213-223. [PMID: 22961726 DOI: 10.1002/nbm.2840] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 06/27/2012] [Accepted: 07/10/2012] [Indexed: 06/01/2023]
Abstract
Currently, there is very limited ability to measure the temperature of the brain, but a direct technique for its estimation in vivo could improve the detection of patients at risk of temperature-related brain damage, help in the diagnosis of stroke and tumour, and provide useful information on the mechanisms of thermoregulation of the brain. In this article, new calibrations in vitro of MRS thermometry using temperature-stabilised reference phantoms are reported. The phantoms comprise two concentric glass spheres: the inner sphere contains the phantom material to be measured by MRS, and the outer sphere contains a substance with a known temperature stable to within 0.2 °C. The substances were freezing organic fixed-point compounds (diphenyl ether and ethylene carbonate, freezing at 26.3 and 35.8 °C, respectively) or temperature-controlled circulating water. The phantom temperature was continuously monitored with a fluoroptic probe calibrated at the National Physical Laboratory with traceability to the International Temperature Scale 1990 (ITS-90). The MRS temperature calibration was obtained by measuring the chemical shift of water relative to N-acetylaspartate (NAA) in a single voxel as a function of temperature using a 1.5-T Philips Intera scanner. Measurements were made for several phantom materials to assess the effect of tissue composition on the water-NAA chemical shift against temperature calibration. The phantom mixtures contained 25 mm of NAA buffered to pH 6.5 or 7.5 and several ionic salts or bovine serum albumin (BSA). Spectra were acquired from 25 to 45 °C. The correlation between frequency differences and phantom temperature was very linear with small residuals. However, the linear fitting parameters varied with ionic composition and BSA concentration. The 'apparent' temperature (calibrated using the water-NAA frequency differences) decreased by approximately 1 °C for every 100 mm increase in ionic concentration and increased proportionally to the concentration of BSA.
Collapse
Affiliation(s)
- E Vescovo
- Imaging, Proteomics and Genomics Research Group, Manchester Academic Health Sciences Centre, University of Manchester, Manchester, UK.
| | | | | | | | | | | |
Collapse
|
31
|
In Vivo Magnetic Resonance Spectroscopic Imaging and Ex Vivo Quantitative Neuropathology by High Resolution Magic Angle Spinning Proton Magnetic Resonance Spectroscopy. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/7657_2011_31] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
32
|
Chadzynski GL, Bender B, Groeger A, Erb M, Klose U. Tissue specific resonance frequencies of water and metabolites within the human brain. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 212:55-63. [PMID: 21752679 DOI: 10.1016/j.jmr.2011.06.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Revised: 06/10/2011] [Accepted: 06/11/2011] [Indexed: 05/31/2023]
Abstract
Chemical shift imaging (CSI) without water suppression was used to examine tissue-specific resonance frequencies of water and metabolites within the human brain. The aim was to verify if there are any regional differences in those frequencies and to determine the influence of chemical shift displacement in slice-selection direction. Unsuppressed spectra were acquired at 3T from nine subjects. Resonance frequencies of water and after water signal removal of total choline, total creatine and NAA were estimated. Furthermore, frequency distances between the water and those resonances were calculated. Results were corrected for chemical shift displacement. Frequency distances between water and metabolites were consistent and greater for GM than for WM. The highest value of WM to GM difference (14ppb) was observed for water to NAA frequency distance. This study demonstrates that there are tissue-specific differences between frequency distances of water and metabolites. Moreover, the influence of chemical shift displacement in slice-selection direction is showed to be negligible.
Collapse
Affiliation(s)
- Grzegorz L Chadzynski
- MR Research Group, Department of Diagnostic and Interventional Neuroradiology, University Hospital Tuebingen, Hoppe-Seyler strasse 3, 72076 Tuebingen, Germany.
| | | | | | | | | |
Collapse
|
33
|
Cady EB, Penrice J, Robertson NJ. Improved reproducibility of MRS regional brain thermometry by 'amplitude-weighted combination'. NMR IN BIOMEDICINE 2011; 24:865-872. [PMID: 21834009 DOI: 10.1002/nbm.1634] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Revised: 09/27/2010] [Accepted: 10/04/2010] [Indexed: 05/31/2023]
Abstract
Brain temperature is important in stroke and trauma. In birth asphyxia, hypothermia improves outcome, but local brain temperature information is needed to optimise therapy. The proton MRS water chemical shift (δ(water) ) is temperature dependent, and the in vivo brain temperature has often been estimated by measuring δ(water) relative to the N-acetylaspartate (NAA) singlet methyl resonance. However, the NAA peak amplitude may be reduced if cerebrospinal fluid occupies part of the MRS voxel and because of the lower concentration in immaturity, pathology and neonatal white matter. These factors can increase random and systematic δ(NAA) errors and also, therefore, MRS brain temperature errors. The aim of this study was to improve MRS brain temperature reproducibility and resilience to pathological, developmental and regional peak amplitude variations by amplitude-weighted combination (AWC) of brain temperatures (T(Cho) , T(Cr) and T(NAA) ) determined using the prominent choline (Cho), total creatine (Cr) and NAA resonances separately as chemical shift references. δ(water) - δ(Cho) , δ(water) - δ(Cr) and δ(water) - δ(NAA) were calibrated against tympanic temperature in piglet brain at 7 T (2.5-cm-diameter surface coil over the parietal lobes; binomial water suppression spin-echo sequence; TE = 540 ms; TR = 5 s). Eight normal human infants underwent thalamic region (Thal) and five occipito-parietal (OP) cerebral MRS at 2.4 T [point-resolved spectroscopy (PRESS) localisation; cubic voxel, 8 mL; water suppression off; TE = 270 ms; TR = 2 s]. AWC with T(Cho) , T(Cr) and T(NAA) weighted by the squared Cho, Cr and NAA peak amplitudes provided the smallest intersubject standard deviations: Thal, 0.45°C; OP, 0.33°C (for T(NAA) values of 0.65°C and 1.12°C, respectively). AWC provided resilience against simulated pathological alterations in Cho, Cr and NAA peak amplitudes, with Thal and OP T(AWC) changing by less than 0.04°C. AWC improves both intersubject reproducibility of MRS temperature estimation and resilience against pathological, anatomical and developmental variation of Cho, Cr and NAA peak amplitudes.
Collapse
Affiliation(s)
- Ernest B Cady
- Department of Medical Physics and Bioengineering, University College London Hospitals NHS Foundation Trust, London, UK.
| | | | | |
Collapse
|
34
|
Pfeil A, Drobnik S, Rzanny R, Aboud A, Böttcher J, Schmidt P, Ortmann C, Mall G, Hekmat K, Brehm B, Reichenbach J, Mayer TE, Wolf G, Hansch A. Compatibility of temporary pacemaker myocardial pacing leads with magnetic resonance imaging: an ex vivo tissue study. Int J Cardiovasc Imaging 2011; 28:317-26. [DOI: 10.1007/s10554-011-9800-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Accepted: 01/08/2011] [Indexed: 11/25/2022]
|
35
|
Jenista ER, Galiana G, Branca RT, Yarmolenko PS, Stokes AM, Dewhirst MW, Warren WS. Application of mixed spin iMQCs for temperature and chemical-selective imaging. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2010; 204:208-18. [PMID: 20303808 PMCID: PMC2874652 DOI: 10.1016/j.jmr.2010.02.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2009] [Revised: 02/22/2010] [Accepted: 02/22/2010] [Indexed: 05/16/2023]
Abstract
The development of accurate and non-invasive temperature imaging techniques has a wide variety of applications in fields such as medicine, chemistry and materials science. Accurate detection of temperature both in phantoms and in vivo can be obtained using iMQCs (intermolecular multiple quantum coherences), as demonstrated in a recent paper. This paper describes the underlying theory of iMQC temperature detection, as well as extensions of that work allowing not only for imaging of absolute temperature but also for imaging of analyte concentrations through chemically-selective spin density imaging.
Collapse
Affiliation(s)
- Elizabeth R Jenista
- Center for Molecular and Biomolecular Imaging, 2220 French Family Science Center, Duke University, Durham, NC 27708, USA.
| | | | | | | | | | | | | |
Collapse
|
36
|
Covaciu L, Rubertsson S, Ortiz-Nieto F, Ahlström H, Weis J. Human brain MR spectroscopy thermometry using metabolite aqueous-solution calibrations. J Magn Reson Imaging 2010; 31:807-14. [DOI: 10.1002/jmri.22107] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
|
37
|
Ferrara KW, Borden MA, Zhang H. Lipid-shelled vehicles: engineering for ultrasound molecular imaging and drug delivery. Acc Chem Res 2009; 42:881-92. [PMID: 19552457 DOI: 10.1021/ar8002442] [Citation(s) in RCA: 267] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ultrasound pressure waves can map the location of lipid-stabilized gas micro-bubbles after their intravenous administration in the body, facilitating an estimate of vascular density and microvascular flow rate. Microbubbles are currently approved by the Food and Drug Administration as ultrasound contrast agents for visualizing opacification of the left ventricle in echocardiography. However, the interaction of ultrasound waves with intravenously-injected lipid-shelled particles, including both liposomes and microbubbles, is a far richer field. Particles can be designed for molecular imaging and loaded with drugs or genes; the mechanical and thermal properties of ultrasound can then effect localized drug release. In this Account, we provide an overview of the engineering of lipid-shelled microbubbles (typical diameter 1000-10 000 nm) and liposomes (typical diameter 65-120 nm) for ultrasound-based applications in molecular imaging and drug delivery. The chemistries of the shell and core can be optimized to enhance stability, circulation persistence, drug loading and release, targeting to and fusion with the cell membrane, and therapeutic biological effects. To assess the biodistribution and pharmacokinetics of these particles, we incorporated positron emission tomography (PET) radioisotopes on the shell. The radionuclide (18)F (half-life approximately 2 h) was covalently coupled to a dipalmitoyl lipid, followed by integration of the labeled lipid into the shell, facilitating short-term analysis of particle pharmacokinetics and metabolism of the lipid molecule. Alternately, labeling a formed particle with (64)Cu (half-life 12.7 h), after prior covalent incorporation of a copper-chelating moiety onto the lipid shell, permits pharmacokinetic study of particles over several days. Stability and persistence in circulation of both liposomes and microbubbles are enhanced by long acyl chains and a poly(ethylene glycol) coating. Vascular targeting has been demonstrated with both nano- and microdiameter particles. Targeting affinity of the microbubble can be modulated by burying the ligand within a polymer brush layer; the application of ultrasound then reveals the ligand, enabling specific targeting of only the insonified region. Microbubbles and liposomes require different strategies for both drug loading and release. Microbubble loading is inhibited by the gas core and enhanced by layer-by-layer construction or conjugation of drug-entrapped particles to the surface. Liposome loading is typically internal and is enhanced by drug-specific loading techniques. Drug release from a microbubble results from the oscillation of the gas core diameter produced by the sound wave, whereas that from a liposome is enhanced by heat produced from the local absorption of acoustic energy within the tissue microenvironment. Biological effects induced by ultrasound, such as changes in cell membrane and vascular permeability, can enhance drug delivery. In particular, as microbubbles oscillate near a vessel wall, shock waves or liquid jets enhance drug transport. Mild heating induced by ultrasound, either before or after injection of the drug, facilitates the transport of liposomes from blood vessels to the tissue interstitium, thus increasing drug accumulation in the target region. Lipid-shelled vehicles offer many opportunities for chemists and engineers; ultrasound-based applications beyond the few currently in common use will undoubtedly soon multiply as molecular construction techniques are further refined.
Collapse
Affiliation(s)
- Katherine W. Ferrara
- Department of Biomedical Engineering, 451 Health Sciences Drive, University of California, Davis, California 95616
| | - Mark A. Borden
- Department of Biomedical Engineering, 451 Health Sciences Drive, University of California, Davis, California 95616
| | - Hua Zhang
- Department of Biomedical Engineering, 451 Health Sciences Drive, University of California, Davis, California 95616
| |
Collapse
|