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Zou R, Xiong T, Zhang L, Li S, Zhao F, Tong Y, Qu Y, Mu D. Proton Magnetic Resonance Spectroscopy Biomarkers in Neonates With Hypoxic-Ischemic Encephalopathy: A Systematic Review and Meta-Analysis. Front Neurol 2018; 9:732. [PMID: 30233483 PMCID: PMC6127251 DOI: 10.3389/fneur.2018.00732] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 08/10/2018] [Indexed: 01/15/2023] Open
Abstract
Background: Hypoxic-ischemic encephalopathy (HIE) is a major contributor to child mortality and morbidity. Reliable prognostication for HIE is of key importance. Proton magnetic resonance spectroscopy (1H-MRS) is a quantitative, non-invasive method that has been demonstrated to be a suitable complementary tool for prediction. The aim of this study was to investigate the prognostic capability of 1H-MRS in the era of therapeutic hypothermia (TH). Methods: Databases, namely MEDLINE, Embase, Web of Science, and the Cochrane library (Cochrane Center Register of Controlled Trials), were searched for studies published before July 17, 2017. Study selection and data extraction were performed by two independent reviewers. The mean difference (MD) or standardized MD (SMD) and 95% confidence interval (CI) were calculated using random-effects models. Subgroup analyses were conducted based on the use of TH. Results: Among the 1,150 relevant studies, seven were included for meta-analysis, but only two small studies were conducted under TH. For 1H-MRS measurement, three peak area ratios revealed predictive values for adverse outcomes in TH subgroup and the combined results (with and without TH): N-acetylaspartate (NAA)/creatine in basal ganglia/thalamus (BG/T) in TH (MD −0.31, 95%CI −0.55 to −0.07) and combined results (MD −0.37, 95% CI −0.49 to −0.25); NAA/choline in BG/T in TH (MD −0.89, 95%CI −1.43 to −0.35) and combined results (MD −0.25, 95%CI −0.42 to −0.07); and myo-inositol/choline in cerebral cortex in TH (MD −1.94, 95%CI −3.69 to −0.19) and combined results (MD −1.64, 95%CI −2.64 to −0.64). Moreover, NAA relative concentration is associated with adverse outcomes: in TH (MD −0.04, 95%CI −0.06 to −0.02) and combined results (MD −0.06, 95%CI −0.11 to −0.01) in white matter; in TH (MD −0.04, 95%CI −0.07 to −0.01) and combined results (MD −0.05, 95%CI −0.07 to −0.02) in gray matter. Conclusions: NAA may be a potential marker in outcome prediction for all HIE subjects. It seems that MDs for the ratios including NAA are larger than for its relative concentration, and therefore are more likely to be measurable in a clinical context. Larger prospective multicenter studies with a standardized protocol for both measurement protocols and analysis methods are required in future studies.
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Affiliation(s)
- Rong Zou
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, China
| | - Tao Xiong
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, China
| | - Li Zhang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, China
| | - Shiping Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, China
| | - Fengyan Zhao
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, China
| | - Yu Tong
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, China
| | - Yi Qu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, China
| | - Dezhi Mu
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, Sichuan University, Chengdu, China
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52
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Splanchnic NIRS monitoring in neonatal care: rationale, current applications and future perspectives. J Perinatol 2018; 38:431-443. [PMID: 29472709 DOI: 10.1038/s41372-018-0075-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 11/22/2017] [Accepted: 11/28/2017] [Indexed: 12/29/2022]
Abstract
Near infrared spectroscopy (NIRS) provides a non-invasive, continuous monitoring of regional tissue oxygenation. NIRS assessment of neonatal splanchnic oxygenation (SrSO2) has gained increasing interest over the last decade, as local hypoxia and ischemia underlie the most feared gut complications in neonates. Current literature provides encouraging evidence in support of SrSO2 reliability in detecting mesenteric hemodynamic changes related to various physiological and pathological conditions in-term and preterm infants. Even so, while splanchnic NIRS monitoring looks promising for investigating gut physiopathology in research settings, further studies are needed to evaluate its feasibility as a routine monitoring tool in neonatal care and to investigate its potential role in clinical decision making. After a brief introduction to NIRS technical principles, this review aims to provide a complete overview of current neonatal applications for splanchnic NIRS monitoring, to discuss its possible limitations and to suggest future directions for research and clinical applications.
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53
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Beausoleil TP, Janaillac M, Barrington KJ, Lapointe A, Dehaes M. Cerebral oxygen saturation and peripheral perfusion in the extremely premature infant with intraventricular and/or pulmonary haemorrhage early in life. Sci Rep 2018; 8:6511. [PMID: 29695729 PMCID: PMC5916916 DOI: 10.1038/s41598-018-24836-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 04/09/2018] [Indexed: 12/29/2022] Open
Abstract
Extremely preterm infants are at higher risk of pulmonary (PH) and intraventricular (IVH) haemorrhage during the transitioning physiology due to immature cardiovascular system. Monitoring of haemodynamics can detect early abnormal circulation that may lead to these complications. We described time-frequency relationships between near infrared spectroscopy (NIRS) cerebral regional haemoglobin oxygen saturation (CrSO2) and preductal peripheral perfusion index (PI), capillary oxygen saturation (SpO2) and heart rate (HR) in extremely preterm infants in the first 72 h of life. Patients were sub-grouped in infants with PH and/or IVH (N H = 8) and healthy controls (N C = 11). Data were decomposed in wavelets allowing the analysis of localized variations of power. This approach allowed to quantify the percentage of time of significant cross-correlation, semblance, gain (transfer function) and coherence between signals. Ultra-low frequencies (<0.28 mHz) were analyzed as slow and prolonged periods of impaired circulation are considered more detrimental than transient fluctuations. Cross-correlation between CrSO2 and oximetry (PI, SpO2 and HR) as well as in-phase semblance and gain between CrSO2 and HR were significantly lower while anti-phase semblance between CrSO2 and HR was significantly higher in PH-IVH infants compared to controls. These differences may reflect haemodynamic instability associated with cerebrovascular autoregulation and hemorrhagic complications observed during the transitioning physiology.
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Affiliation(s)
- Thierry P Beausoleil
- Institute of Biomedical Engineering, University of Montréal, Montréal, Canada.,Research Centre, CHU Sainte-Justine, Montréal, Canada
| | - Marie Janaillac
- Department of Pediatrics, Division of Neonatology, CHU Sainte-Justine and University of Montréal, Montréal, Canada
| | - Keith J Barrington
- Research Centre, CHU Sainte-Justine, Montréal, Canada.,Department of Pediatrics, Division of Neonatology, CHU Sainte-Justine and University of Montréal, Montréal, Canada
| | - Anie Lapointe
- Department of Pediatrics, Division of Neonatology, CHU Sainte-Justine and University of Montréal, Montréal, Canada
| | - Mathieu Dehaes
- Research Centre, CHU Sainte-Justine, Montréal, Canada. .,Department of Radiology, Radio-oncology and Nuclear Medicine, University of Montréal, Montréal, Canada.
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54
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Correlations between near-infrared spectroscopy, perfusion index, and cardiac outputs in extremely preterm infants in the first 72 h of life. Eur J Pediatr 2018; 177:541-550. [PMID: 29374830 DOI: 10.1007/s00431-018-3096-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 12/14/2017] [Accepted: 01/17/2018] [Indexed: 10/18/2022]
Abstract
UNLABELLED Haemodynamic assessment during the transitional period in preterm infants is challenging. We aimed to describe the relationships between cerebral regional tissue oxygen saturation (CrSO2), perfusion index (PI), echocardiographic, and clinical parameters in extremely preterm infants in their first 72 h of life. Twenty newborns born at < 28 weeks of gestation were continuously monitored with CrSO2 and preductal PI. Cardiac output was measured at H6, H24, H48, and H72. The median gestational age and birth weight were 25.0 weeks (24-26) and 750 g (655-920), respectively. CrSO2 and preductal PI had r values < 0.35 with blood gases, lactates, haemoglobin, and mean blood pressure. Cardiac output significantly increased over the 72 h of the study period. Fifteen patients had at least one episode of low left and/or right ventricular output (RVO), during which there was a strong correlation between CrSO2 and superior vena cava (SVC) flow (at H6 (r = 0.74) and H24 (r = 0.86)) and between PI and RVO (at H6 (r = 0.68) and H24 (r = 0.92)). Five patients had low SVC flow (≤ 40 mL/kg/min) at H6, during which PI was strongly correlated with RVO (r = 0.98). CONCLUSION CrSO2 and preductal PI are strongly correlated with cardiac output during low cardiac output states. What is Known: • Perfusion index and near-infrared spectroscopy are non-invasive tools to evaluate haemodynamics in preterm infants. • Pre- and postductal perfusion indexes strongly correlate with left ventricular output in term infants, and near-infrared spectroscopy has been validated to assess cerebral oxygenation in term and preterm infants. What is New: • Cerebral regional tissue oxygen saturation and preductal perfusion index were strongly correlated with cardiac output during low cardiac output states. • The strength of the correlation between cerebral regional tissue oxygen saturation, preductal perfusion index, and cardiac output varied in the first 72 h of life, reflecting the complexity of the transitional physiology.
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Towns M, Rosenbaum P, Palisano R, Wright FV. Should the Gross Motor Function Classification System be used for children who do not have cerebral palsy? Dev Med Child Neurol 2018; 60:147-154. [PMID: 29105760 DOI: 10.1111/dmcn.13602] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/25/2017] [Indexed: 12/11/2022]
Abstract
UNLABELLED This literature review addressed four questions. (1) In which populations other than cerebral palsy (CP) has the Gross Motor Function Classification System (GMFCS) been applied? (2) In what types of study, and why was it used? (3) How was it modified to facilitate these applications? (4) What justifications and evidence of psychometric adequacy were used to support its application? A search of PubMed, MEDLINE, and Embase databases (January 1997 to April 2017) using the terms: 'GMFCS' OR 'Gross Motor Function Classification System' yielded 2499 articles. 118 met inclusion criteria and reported children/adults with 133 health conditions/clinical descriptions other than CP. Three broad GMFCS applications were observed: as a categorization tool, independent variable, or outcome measure. While the GMFCS is widely used for children with health conditions/clinical description other than CP, researchers rarely provided adequate justification for these uses. We offer recommendations for development/validation of other condition-specific classification systems and discuss the potential need for a generic gross motor function classification system. WHAT THIS PAPER ADDS The Gross Motor Function Classification System should not be used outside cerebral palsy or as an outcome measure. The authors provide recommendations for development and validation of condition-specific or generic classification systems.
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Affiliation(s)
- Megan Towns
- Bloorview Research Institute, Toronto, ON, Canada.,Rehabilitation Sciences Institute, University of Toronto, Toronto, ON, Canada
| | - Peter Rosenbaum
- CanChild Centre for Childhood Disability Research, McMaster University, Hamilton, ON, Canada.,Department of Pediatrics, McMaster University, Hamilton, ON, Canada
| | - Robert Palisano
- CanChild Centre for Childhood Disability Research, McMaster University, Hamilton, ON, Canada.,Physical Therapy and Rehabilitation Science Department, Drexel University, Philadelphia, PA, USA
| | - F Virginia Wright
- Bloorview Research Institute, Toronto, ON, Canada.,Rehabilitation Sciences Institute, University of Toronto, Toronto, ON, Canada.,CanChild Centre for Childhood Disability Research, McMaster University, Hamilton, ON, Canada.,Department of Physical Therapy, University of Toronto, Toronto, ON, Canada
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56
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Farzam P, Buckley EM, Lin PY, Hagan K, Grant PE, Inder TE, Carp SA, Franceschini MA. Shedding light on the neonatal brain: probing cerebral hemodynamics by diffuse optical spectroscopic methods. Sci Rep 2017; 7:15786. [PMID: 29150648 PMCID: PMC5693925 DOI: 10.1038/s41598-017-15995-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 11/03/2017] [Indexed: 11/24/2022] Open
Abstract
Investigating the cerebral physiology of healthy term newborns' brains is important for better understanding perinatal brain injuries, of which the most common etiologies are hypoxia and ischemia. Hence, cerebral blood flow and cerebral oxygenation are important biomarkers of brain health. In this study, we employed a hybrid diffuse optical system consisting of diffuse correlation spectroscopy (DCS) and frequency-domain near infrared spectroscopy (FDNIRS) to measure hemoglobin concentration, oxygen saturation, and indices of cerebral blood flow and metabolism. We measured 30 term infants to assess the optical and physiological characteristics of the healthy neonatal brain in the frontal, temporal, and parietal lobes. We observed higher metabolism in the right hemisphere compared to the left and a positive correlation between gestational age and the level of cerebral hemoglobin concentration, blood volume, and oxygen saturation. Moreover, we observed higher cerebral blood flow and lower oxygen saturation in females compared to males. The delayed maturation in males and the sexual dimorphism in cerebral hemodynamics may explain why males are more vulnerable to perinatal brain injuries than females.
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Affiliation(s)
- Parisa Farzam
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA.
| | - Erin M Buckley
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
- Georgia Institute of Technology, Atlanta, GA, 30322, USA
| | - Pei-Yi Lin
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - Katherine Hagan
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - P Ellen Grant
- Fetal-Neonatal Neuroimaging and Developmental Science Center, Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Terrie Eleanor Inder
- Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Stefan A Carp
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - Maria Angela Franceschini
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
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57
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Shedding light on the neonatal brain: probing cerebral hemodynamics by diffuse optical spectroscopic methods. Sci Rep 2017. [PMID: 29150648 DOI: 10.1038/s41598‐017‐15995‐1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Investigating the cerebral physiology of healthy term newborns' brains is important for better understanding perinatal brain injuries, of which the most common etiologies are hypoxia and ischemia. Hence, cerebral blood flow and cerebral oxygenation are important biomarkers of brain health. In this study, we employed a hybrid diffuse optical system consisting of diffuse correlation spectroscopy (DCS) and frequency-domain near infrared spectroscopy (FDNIRS) to measure hemoglobin concentration, oxygen saturation, and indices of cerebral blood flow and metabolism. We measured 30 term infants to assess the optical and physiological characteristics of the healthy neonatal brain in the frontal, temporal, and parietal lobes. We observed higher metabolism in the right hemisphere compared to the left and a positive correlation between gestational age and the level of cerebral hemoglobin concentration, blood volume, and oxygen saturation. Moreover, we observed higher cerebral blood flow and lower oxygen saturation in females compared to males. The delayed maturation in males and the sexual dimorphism in cerebral hemodynamics may explain why males are more vulnerable to perinatal brain injuries than females.
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58
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Roberts SB, Franceschini MA, Krauss A, Lin PY, Braima de Sa A, Có R, Taylor S, Brown C, Chen O, Johnson EJ, Pruzensky W, Schlossman N, Balé C, Wu KC(T, Hagan K, Saltzman E, Muentener P. A Pilot Randomized Controlled Trial of a New Supplementary Food Designed to Enhance Cognitive Performance during Prevention and Treatment of Malnutrition in Childhood. Curr Dev Nutr 2017; 1:e000885. [PMID: 29658962 PMCID: PMC5898396 DOI: 10.3945/cdn.117.000885] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 06/11/2017] [Accepted: 10/12/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Cognitive impairment associated with childhood malnutrition and stunting is generally considered irreversible. OBJECTIVE The aim was to test a new nutritional supplement for the prevention and treatment of moderate-acute malnutrition (MAM) focused on enhancing cognitive performance. METHODS An 11-wk, village-randomized, controlled pilot trial was conducted in 78 children aged 1-3 or 5-7 y living in villages in Guinea-Bissau. The supplement contained 291 kcal/d for young children and 350 kcal/d for older children and included 5 nutrients and 2 flavan-3-ol-rich ingredients not present in current food-based recommendations for MAM. Local bakers prepared the supplement from a combination of locally sourced items and an imported mix of ingredients, and it was administered by community health workers 5 d/wk. The primary outcome was executive function abilities at 11 wk. Secondary outcomes included additional cognitive measures and changes in z scores for weight (weight-for-age) and height (height-for-age) and hemoglobin concentrations at 11 wk. An index of cerebral blood flow (CBF) was also measured at 11 wk to explore the use of this measurement as a biological index of cognitive impairment. RESULTS There were no significant differences in any outcome between groups at baseline. There was a beneficial effect of random assignment to the supplement group on working memory at 11 wk in children aged 1-3 y (P < 0.05). This difference contrasted with no effect in older children and was not associated with faster growth rate. In addition, CBF correlated with task-switching performance (P < 0.05). CONCLUSIONS These preliminary data suggest that cognitive impairment can be monitored with measurement of CBF. In addition, the findings provide preliminary data that suggest that it may be possible to improve poor cognitive performance in young children through changes in the nutritional formulation of supplementary foods used to prevent and treat MAM. Powered studies of the new supplement formulation are needed. This trial was registered at clinicaltrials.gov as NCT03017209.
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Affiliation(s)
- Susan B Roberts
- USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA
| | | | - Amy Krauss
- USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
| | - Pei-Yi Lin
- Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA
| | - Augusto Braima de Sa
- International Partnership for Human Development, Leesburg, VA
- International Partnership for Human Development, Bissau, Guinea-Bissau
| | - Raimundo Có
- International Partnership for Human Development, Leesburg, VA
- International Partnership for Human Development, Bissau, Guinea-Bissau
| | - Salima Taylor
- USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
| | - Carrie Brown
- USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
| | - Oliver Chen
- USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA
| | - Elizabeth J Johnson
- USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA
| | - William Pruzensky
- International Partnership for Human Development, Leesburg, VA
- International Partnership for Human Development, Bissau, Guinea-Bissau
| | | | - Carlito Balé
- International Partnership for Human Development, Leesburg, VA
- International Partnership for Human Development, Bissau, Guinea-Bissau
| | - Kuan-Cheng (Tony) Wu
- Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA
| | - Katherine Hagan
- Athinoula A Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA
| | - Edward Saltzman
- USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA
- Friedman School of Nutrition Science and Policy, Tufts University, Boston, MA
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59
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Hachem LD, Ahuja CS, Fehlings MG. Assessment and management of acute spinal cord injury: From point of injury to rehabilitation. J Spinal Cord Med 2017; 40:665-675. [PMID: 28571527 PMCID: PMC5778930 DOI: 10.1080/10790268.2017.1329076] [Citation(s) in RCA: 177] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
CONTEXT Spinal cord injury (SCI) is a devastating condition that can lead to significant neurological impairment and reduced quality of life. Despite advancements in our understanding of the pathophysiology and secondary injury mechanisms involved in SCI, there are currently very few effective treatments for this condition. The field, however, is rapidly changing as new treatments are developed and key discoveries are made. METHODS In this review, we outline the pathophysiology, management, and long-term rehabilitation of individuals with traumatic SCI. We also provide an in-depth overview of emerging therapies along the spectrum of the translational pipeline. EVIDENCE SYNTHESIS The concept of "time is spine" refers to the concept which emphasizes the importance of early transfer to specialized centers, early decompressive surgery, and early delivery of other treatments (e.g. blood pressure augmentation, methylprednisolone) to affect long-term outcomes. Another important evolution in management has been the recognition and prevention of the chronic complications of SCI including respiratory compromise, bladder dysfunction, Charcot joints, and pressure sores through directed interventions along with early integration of physical rehabilitation and mobilization. There have also been significant advances in neuroprotective and neuroregenerative strategies for SCI, many of which are actively in clinical trial including riluzole, Cethrin, stem cell transplantation, and the use of functional electrical stimulation. CONCLUSION Pharmacologic treatments, cell-based therapies, and other technology-driven interventions will likely play a combinatorial role in the evolving management of SCI as the field continues to evolve.
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Affiliation(s)
- Laureen D. Hachem
- Institute of Medical Science, University of Toronto, Toronto, ONT, Canada
| | - Christopher S. Ahuja
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, ONT, Canada
- Institute of Medical Science, University of Toronto, Toronto, ONT, Canada
| | - Michael G. Fehlings
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, ONT, Canada
- Institute of Medical Science, University of Toronto, Toronto, ONT, Canada
- McEwen Centre for Regenerative Medicine, UHN, University of Toronto, Toronto, ONT, Canada
- Department of Surgery, University of Toronto, Toronto, ONT, Canada
- Spine Program, University of Toronto, Toronto, ONT, Canada
- McLaughlin Center in Molecular Medicine, University of Toronto, Toronto, ONT, Canada
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60
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Ahuja CS, Nori S, Tetreault L, Wilson J, Kwon B, Harrop J, Choi D, Fehlings MG. Traumatic Spinal Cord Injury-Repair and Regeneration. Neurosurgery 2017; 80:S9-S22. [PMID: 28350947 DOI: 10.1093/neuros/nyw080] [Citation(s) in RCA: 503] [Impact Index Per Article: 71.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 01/12/2017] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Traumatic spinal cord injuries (SCI) have devastating consequences for the physical, financial, and psychosocial well-being of patients and their caregivers. Expediently delivering interventions during the early postinjury period can have a tremendous impact on long-term functional recovery. PATHOPHYSIOLOGY This is largely due to the unique pathophysiology of SCI where the initial traumatic insult (primary injury) is followed by a progressive secondary injury cascade characterized by ischemia, proapoptotic signaling, and peripheral inflammatory cell infiltration. Over the subsequent hours, release of proinflammatory cytokines and cytotoxic debris (DNA, ATP, reactive oxygen species) cyclically adds to the harsh postinjury microenvironment. As the lesions mature into the chronic phase, regeneration is severely impeded by the development of an astroglial-fibrous scar surrounding coalesced cystic cavities. Addressing these challenges forms the basis of current and upcoming treatments for SCI. MANAGEMENT This paper discusses the evidence-based management of a patient with SCI while emphasizing the importance of early definitive care. Key neuroprotective therapies are summarized including surgical decompression, methylprednisolone, and blood pressure augmentation. We then review exciting neuroprotective interventions on the cusp of translation such as Riluzole, Minocycline, magnesium, therapeutic hypothermia, and CSF drainage. We also explore the most promising neuroregenerative strategies in trial today including Cethrin™, anti-NOGO antibody, cell-based approaches, and bioengineered biomaterials. Each section provides a working knowledge of the key preclinical and patient trials relevant to clinicians while highlighting the pathophysiologic rationale for the therapies. CONCLUSION We conclude with our perspectives on the future of treatment and research in this rapidly evolving field.
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Affiliation(s)
- Christopher S Ahuja
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada.,Institute of Medical Science, University of Toronto, Toronto, Canada.,Department of Surgery, University of Toronto, Toronto, Canada.,Department of Genetics and Development, University of Toronto, Toronto, Canada
| | - Satoshi Nori
- Department of Genetics and Development, University of Toronto, Toronto, Canada
| | | | - Jefferson Wilson
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada.,Department of Surgery, University of Toronto, Toronto, Canada.,Spine Program, University of Toronto, Toronto, Canada
| | - Brian Kwon
- Vancouver Spine Institute, Vancouver General Hospital, Vancouver, Canada.,Department of Surgery, University of British Columbia, Vancouver, Canada
| | - James Harrop
- Thomas Jefferson University Hospital, Philadelphia, Pennsylvania
| | - David Choi
- National Hospital for Neurology and Neurosurgery, University College London, London, England
| | - Michael G Fehlings
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada.,Institute of Medical Science, University of Toronto, Toronto, Canada.,Department of Surgery, University of Toronto, Toronto, Canada.,Spine Program, University of Toronto, Toronto, Canada.,Department of Genetics and Development, University of Toronto, Toronto, Canada
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61
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Jain SV, Pagano L, Gillam-Krakauer M, Slaughter JC, Pruthi S, Engelhardt B. Cerebral regional oxygen saturation trends in infants with hypoxic-ischemic encephalopathy. Early Hum Dev 2017; 113:55-61. [PMID: 28772198 DOI: 10.1016/j.earlhumdev.2017.07.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 06/29/2017] [Accepted: 07/02/2017] [Indexed: 11/30/2022]
Abstract
BACKGROUND Neurological outcomes in neonatal hypoxic-ischemic encephalopathy (HIE) continue to be sub-optimal despite therapeutic hypothermia (TH). Cerebral near-infrared spectroscopy provides real-time regional oxygen saturation (CrSO2) that may be a marker of adverse MRI findings and neurodevelopmental outcomes. AIM The aim of this study was to examine the value of CrSO2 monitoring in infants with HIE undergoing TH. STUDY DESIGN AND SUBJECTS In this prospective study, CrSO2 was continuously recorded in 21 infants with HIE admitted for TH. OUTCOME MEASURES Brain MRI signal abnormalities at 2weeks were scored in individual brain region and classified as none/mild, moderate and severe. 13 infants completed Bayley Scales of Infant Development (BSID) testing at 18-24months. RESULTS Between 24 and 36h of life, there was a significant increase in odds of having moderate-severe brain MRI abnormalities with higher absolute CrSO2 values. Per 10% increase in absolute CrSO2, the odds ratio for moderate-severe brain MRI abnormalities was greatest at 30h (OR 3.78; confidence intervals (CI): 1.23-11.6, p=0.011). CrSO2 increased more rapidly in infants with greater injury seen on MRI (0.20/h for MRI scores 0/1, by 0.48/h for MRI score 2, and by 0.68/h for MRI score 3, p=0.05). At 30h, absolute CrSO2 correlated significantly with abnormal MRI findings in basal ganglia (92% vs. 78%, p=0.001), white matter (88% vs. 76%, p=0.01), posterior limb of internal capsule (92% vs. 78%, p=0.001), and brain stem (94% vs. 80%, p=0.03) but not with cortical injury (86% vs. 80%, p=0.17). Higher CrSO2 beyond 24h correlated with greater odds of worse BSID scores. CONCLUSIONS Increasing CrSO2 is associated with moderate-severe brain injury as assessed by MRI. Higher absolute CrSO2 values during TH correlates with subcortical injury on MRI and poor neurodevelopmental outcomes in infants with HIE undergoing TH. CrSO2 can inform providers seeking early identification of patients at risk of worse injury who may benefit from further intervention.
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Affiliation(s)
- Siddharth V Jain
- Division of Pediatric and Developmental Neurology, Department of Neurology, Washington University School of Medicine, St. Louis, MO, United States.
| | - Lindsay Pagano
- Division of Pediatric Neurology, Department of Pediatrics, Vanderbilt University, Nashville, TN, United States
| | - Maria Gillam-Krakauer
- Division of Neonatology, Department of Pediatrics, Vanderbilt University, Nashville, TN, United States
| | - James C Slaughter
- Department of Biostatistics, Vanderbilt University, Nashville, TN, United States
| | - Sumit Pruthi
- Division of Pediatric Neuroradiology, Department of Pediatrics, Vanderbilt University, Nashville, TN, United States
| | - Barbara Engelhardt
- Division of Neonatology, Department of Pediatrics, Vanderbilt University, Nashville, TN, United States
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Chiarelli AM, Zappasodi F, Di Pompeo F, Merla A. Simultaneous functional near-infrared spectroscopy and electroencephalography for monitoring of human brain activity and oxygenation: a review. NEUROPHOTONICS 2017; 4:041411. [PMID: 28840162 PMCID: PMC5566595 DOI: 10.1117/1.nph.4.4.041411] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 07/24/2017] [Indexed: 05/24/2023]
Abstract
Multimodal monitoring has become particularly common in the study of human brain function. In this context, combined, synchronous measurements of functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG) are getting increased interest. Because of the absence of electro-optical interference, it is quite simple to integrate these two noninvasive recording procedures of brain activity. fNIRS and EEG are both scalp-located procedures. fNIRS estimates brain hemodynamic fluctuations relying on spectroscopic measurements, whereas EEG captures the macroscopic temporal dynamics of brain electrical activity through passive voltages evaluations. The "orthogonal" neurophysiological information provided by the two technologies and the increasing interest in the neurovascular coupling phenomenon further encourage their integration. This review provides, together with an introduction regarding the principles and future directions of the two technologies, an evaluation of major clinical and nonclinical applications of this flexible, low-cost combination of neuroimaging modalities. fNIRS-EEG systems exploit the ability of the two technologies to be conducted in an environment or experimental setting and/or on subjects that are generally not suited for other neuroimaging modalities, such as functional magnetic resonance imaging, positron emission tomography, and magnetoencephalography. fNIRS-EEG brain monitoring settles itself as a useful multimodal tool for brain electrical and hemodynamic activity investigation.
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Affiliation(s)
- Antonio M. Chiarelli
- University of Illinois at Urbana Champaign, Beckman Institute, Urbana, Illinois, United States
| | - Filippo Zappasodi
- Università G. d’Annunzio, Department of Neuroscience, Imaging and Clinical Science, Chieti, Italy
- Università G. d’Annunzio, Institute for Advanced Biomedical Technologies, Chieti, Italy
| | - Francesco Di Pompeo
- Università G. d’Annunzio, Department of Neuroscience, Imaging and Clinical Science, Chieti, Italy
- Università G. d’Annunzio, Institute for Advanced Biomedical Technologies, Chieti, Italy
| | - Arcangelo Merla
- Università G. d’Annunzio, Department of Neuroscience, Imaging and Clinical Science, Chieti, Italy
- Università G. d’Annunzio, Institute for Advanced Biomedical Technologies, Chieti, Italy
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63
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Cerebral near-infrared spectroscopy insensitively detects low cerebral venous oxygen saturations after stage 1 palliation. J Thorac Cardiovasc Surg 2017; 154:1056-1062. [DOI: 10.1016/j.jtcvs.2017.03.154] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 01/20/2017] [Accepted: 03/16/2017] [Indexed: 11/21/2022]
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Nori S, Ahuja CS, Fehlings MG. Translational Advances in the Management of Acute Spinal Cord Injury: What is New? What is Hot? Neurosurgery 2017; 64:119-128. [DOI: 10.1093/neuros/nyx217] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 04/04/2017] [Indexed: 01/10/2023] Open
Affiliation(s)
- Satoshi Nori
- Department of Genetics and Develop-ment, University of Toronto, Toronto, Canada
| | - Christopher S. Ahuja
- Department of Genetics and Develop-ment, University of Toronto, Toronto, Canada
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada
- Institute of Medical Science, University of Toronto, Toronto, Canada
- Department of Surgery, University of Toronto, Toronto, Canada
| | - Michael G. Fehlings
- Department of Genetics and Develop-ment, University of Toronto, Toronto, Canada
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Canada
- Institute of Medical Science, University of Toronto, Toronto, Canada
- Department of Surgery, University of Toronto, Toronto, Canada
- Spine Program, University of Toronto, Toronto, Canada
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65
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Gumulak R, Lucanova LC, Zibolen M. Use of near-infrared spectroscopy (NIRS) in cerebral tissue oxygenation monitoring in neonates. Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub 2017; 161:128-133. [DOI: 10.5507/bp.2017.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 03/20/2017] [Indexed: 11/23/2022] Open
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Suen KF, Leung R, Leung LP. Therapeutic Hypothermia for Asphyxial Out-of-Hospital Cardiac Arrest Due to Drowning: A Systematic Review of Case Series and Case Reports. Ther Hypothermia Temp Manag 2017; 7:210-221. [PMID: 28570829 DOI: 10.1089/ther.2017.0011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The objective of this review was to summarize published evidence of the effectiveness of therapeutic hypothermia in patients with drowning-associated asphyxial out-of-hospital cardiac arrest (OHCA) and to explore any preliminary favorable factors in the management of therapeutic hypothermia to improve survival and neurological outcome. Drowning may result in asphyxial OHCA or hypothermic OHCA, but the former does not provide any potential neuroprotective effect as the latter may do. Electronic literature searches of Ovid Medline, Embase, Cochrane Library, and Scopus were performed for all years from inception to July 2016. Primary studies in the form of case reports, letters to the editor, and others with higher quality are included, but guidelines, reviews, editorials, textbook chapters, conference abstracts, and nonhuman studies are excluded. Non-English articles are excluded. Relevant studies are then deemed eligible if the drowning OHCA patient's initial temperature was above 28°C, which implies asphyxial cardiac arrest, and intentional therapeutic hypothermia was instituted. Because of the narrow scope of interest and strict definition of the condition, limited studies addressed it, and no randomized controlled trials (RCT) could be selected. Thirteen studies covering 35 patients are included. No quantitative synthesis, assessment of study quality, or assessment of bias was performed. It is conjectured that extended therapeutic hypothermia of 48-72 hours might help prevent reperfusion injury during the intermediate phase of postcardiac arrest care to benefit patients of drowning-associated asphyxial OHCA, but this finding only serves as preliminary observation for future research. No conclusive recommendation could be made regarding the duration of and the time of onset of therapeutic hypothermia. Future research should put effort on RCT, particularly the effect of extended duration of 48-72 hours. Important parameters should be reported in detail. Asphyxial and hypothermic OHCA should be differentiated.
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Affiliation(s)
- K-F Suen
- 1 School of Medicine, University College Dublin , Dublin, Ireland
| | - Reynold Leung
- 2 Emergency Medicine Unit, Li Ka Shing Faculty of Medicine, The University of Hong Kong , Hong Kong, Hong Kong
| | - Ling-Pong Leung
- 2 Emergency Medicine Unit, Li Ka Shing Faculty of Medicine, The University of Hong Kong , Hong Kong, Hong Kong
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67
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Shang Y, Li T, Yu G. Clinical applications of near-infrared diffuse correlation spectroscopy and tomography for tissue blood flow monitoring and imaging. Physiol Meas 2017; 38:R1-R26. [PMID: 28199219 PMCID: PMC5726862 DOI: 10.1088/1361-6579/aa60b7] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Blood flow is one such available observable promoting a wealth of physiological insight both individually and in combination with other metrics. APPROACH Near-infrared diffuse correlation spectroscopy (DCS) and, to a lesser extent, diffuse correlation tomography (DCT), have increasingly received interest over the past decade as noninvasive methods for tissue blood flow measurements and imaging. DCS/DCT offers several attractive features for tissue blood flow measurements/imaging such as noninvasiveness, portability, high temporal resolution, and relatively large penetration depth (up to several centimeters). MAIN RESULTS This review first introduces the basic principle and instrumentation of DCS/DCT, followed by presenting clinical application examples of DCS/DCT for the diagnosis and therapeutic monitoring of diseases in a variety of organs/tissues including brain, skeletal muscle, and tumor. SIGNIFICANCE Clinical study results demonstrate technical versatility of DCS/DCT in providing important information for disease diagnosis and intervention monitoring.
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Affiliation(s)
- Yu Shang
- Key Laboratory of Instrumentation Science & Dynamic Measurement, North University of China, No.3 Xueyuan Road, Taiyuan, Shanxi 030051, China
| | - Ting Li
- State Key Lab Elect Thin Film & Integrated Device, University of Electronic Science & Technology of China, Chengdu, Sichuan 610054, China
| | - Guoqiang Yu
- Department of Biomedical Engineering, University of Kentucky, 514C RMB, 143 Graham Avenue, Lexington, KY 40506-0108, USA
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Glucose and Intermediary Metabolism and Astrocyte–Neuron Interactions Following Neonatal Hypoxia–Ischemia in Rat. Neurochem Res 2016; 42:115-132. [DOI: 10.1007/s11064-016-2149-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 12/09/2016] [Accepted: 12/10/2016] [Indexed: 11/27/2022]
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69
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Analgesia, sedation, and neuromuscular blockade during targeted temperature management after cardiac arrest. Best Pract Res Clin Anaesthesiol 2016; 29:435-50. [PMID: 26670815 DOI: 10.1016/j.bpa.2015.09.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 09/22/2015] [Indexed: 12/16/2022]
Abstract
The approach to sedation, analgesia, and neuromuscular blockade during targeted temperature management (TTM) remains largely unstudied, forcing clinicians to adapt previous research from other patient environments. During TTM, very little data guide drug selection, doses, and specific therapeutic goals. Sedation should be deep enough to prevent awareness during neuromuscular blockade, but titration is complex as metabolism and clearance are delayed for almost all drugs during hypothermia. Deeper sedation is associated with prolonged intensive care unit (ICU) and ventilator therapy, increased delirium and infection, and delayed wakening which can confound early critical neurological assessments, potentially resulting in erroneous prognostication and inappropriate withdrawal of life support. We review the potential therapeutic goals for sedation, analgesia, and neuromuscular blockade during TTM; the adverse events associated with that treatment; data suggesting that TTM and organ dysfunction impair drug metabolism; and controversies and potential benefits of specific monitoring. We also highlight the areas needing better research to guide our therapy.
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70
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Sutin J, Zimmerman B, Tyulmankov D, Tamborini D, Wu KC, Selb J, Gulinatti A, Rech I, Tosi A, Boas DA, Franceschini MA. Time-domain diffuse correlation spectroscopy. OPTICA 2016; 3:1006-1013. [PMID: 28008417 PMCID: PMC5166986 DOI: 10.1364/optica.3.001006] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Physiological monitoring of oxygen delivery to the brain has great significance for improving the management of patients at risk for brain injury. Diffuse correlation spectroscopy (DCS) is a rapidly growing optical technology able to non-invasively assess the blood flow index (BFi) at the bedside. The current limitations of DCS are the contamination introduced by extracerebral tissue and the need to know the tissue's optical properties to correctly quantify the BFi. To overcome these limitations, we have developed a new technology for time-resolved diffuse correlation spectroscopy. By operating DCS in the time domain (TD-DCS), we are able to simultaneously acquire the temporal point-spread function to quantify tissue optical properties and the autocorrelation function to quantify the BFi. More importantly, by applying time-gated strategies to the DCS autocorrelation functions, we are able to differentiate between short and long photon paths through the tissue and determine the BFi for different depths. Here, we present the novel device and we report the first experiments in tissue-like phantoms and in rodents. The TD-DCS method opens many possibilities for improved non-invasive monitoring of oxygen delivery in humans.
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Affiliation(s)
- Jason Sutin
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Bernhard Zimmerman
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Danil Tyulmankov
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Davide Tamborini
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
- Dipartimento di Elettronica, Informazione e Bioingegneria at Politecnico di Milano, Milano, Italy
| | - Kuan Cheng Wu
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Juliette Selb
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Angelo Gulinatti
- Dipartimento di Elettronica, Informazione e Bioingegneria at Politecnico di Milano, Milano, Italy
| | - Ivan Rech
- Dipartimento di Elettronica, Informazione e Bioingegneria at Politecnico di Milano, Milano, Italy
| | - Alberto Tosi
- Dipartimento di Elettronica, Informazione e Bioingegneria at Politecnico di Milano, Milano, Italy
| | - David A. Boas
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | - Maria Angela Franceschini
- Optics Division at the Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA
- Corresponding author:
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Chalia M, Lee CW, Dempsey LA, Edwards AD, Singh H, Michell AW, Everdell NL, Hill RW, Hebden JC, Austin T, Cooper RJ. Hemodynamic response to burst-suppressed and discontinuous electroencephalography activity in infants with hypoxic ischemic encephalopathy. NEUROPHOTONICS 2016; 3:031408. [PMID: 27446969 PMCID: PMC4945004 DOI: 10.1117/1.nph.3.3.031408] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Accepted: 03/23/2016] [Indexed: 05/24/2023]
Abstract
Burst suppression (BS) is an electroencephalographic state associated with a profound inactivation of the brain. BS and pathological discontinuous electroencephalography (EEG) are often observed in term-age infants with neurological injury and can be indicative of a poor outcome and lifelong disability. Little is known about the neurophysiological mechanisms of BS or how the condition relates to the functional state of the neonatal brain. We used simultaneous EEG and diffuse optical tomography (DOT) to investigate whether bursts of EEG activity in infants with hypoxic ischemic encephalopathy are associated with an observable cerebral hemodynamic response. We were able to identify significant changes in concentration of both oxy and deoxyhemoglobin that are temporally correlated with EEG bursts and present a relatively consistent morphology across six infants. Furthermore, DOT reveals patient-specific spatial distributions of this hemodynamic response that may be indicative of a complex pattern of cortical activation underlying discontinuous EEG activity that is not readily apparent in scalp EEG.
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Affiliation(s)
- Maria Chalia
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, Department of Neonatology, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Chuen Wai Lee
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, Department of Neonatology, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Laura A. Dempsey
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- University College London, Department of Medical Physics and Biomedical Engineering, Malet Place Engineering Building, Gower Street, London WC1E 6BT, United Kingdom
| | - Andrea D. Edwards
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, Department of Neonatology, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Harsimrat Singh
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- University College London, Department of Medical Physics and Biomedical Engineering, Malet Place Engineering Building, Gower Street, London WC1E 6BT, United Kingdom
| | - Andrew W. Michell
- Cambridge University Hospitals NHS Foundation Trust, Department of Clinical Neurophysiology, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Nicholas L. Everdell
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- University College London, Department of Medical Physics and Biomedical Engineering, Malet Place Engineering Building, Gower Street, London WC1E 6BT, United Kingdom
| | - Reuben W. Hill
- University College London, Department of Medical Physics and Biomedical Engineering, Malet Place Engineering Building, Gower Street, London WC1E 6BT, United Kingdom
| | - Jeremy C. Hebden
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- University College London, Department of Medical Physics and Biomedical Engineering, Malet Place Engineering Building, Gower Street, London WC1E 6BT, United Kingdom
| | - Topun Austin
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, Department of Neonatology, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
| | - Robert J. Cooper
- Cambridge University Hospitals NHS Foundation Trust, The Rosie Hospital, The Evelyn Perinatal Imaging Centre, neoLAB, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, United Kingdom
- University College London, Department of Medical Physics and Biomedical Engineering, Malet Place Engineering Building, Gower Street, London WC1E 6BT, United Kingdom
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Wisnowski JL, Wu TW, Reitman AJ, McLean C, Friedlich P, Vanderbilt D, Ho E, Nelson MD, Panigrahy A, Blüml S. The effects of therapeutic hypothermia on cerebral metabolism in neonates with hypoxic-ischemic encephalopathy: An in vivo 1H-MR spectroscopy study. J Cereb Blood Flow Metab 2016; 36:1075-86. [PMID: 26661180 PMCID: PMC4908621 DOI: 10.1177/0271678x15607881] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 08/26/2015] [Indexed: 10/22/2022]
Abstract
Therapeutic hypothermia has emerged as the first empirically supported therapy for neuroprotection in neonates with hypoxic-ischemic encephalopathy (HIE). We used magnetic resonance spectroscopy ((1)H-MRS) to characterize the effects of hypothermia on energy metabolites, neurotransmitters, and antioxidants. Thirty-one neonates with HIE were studied during hypothermia and after rewarming. Metabolite concentrations (mmol/kg) were determined from the thalamus, basal ganglia, cortical grey matter, and cerebral white matter. In the thalamus, phosphocreatine concentrations were increased by 20% during hypothermia when compared to after rewarming (3.49 ± 0.88 vs. 2.90 ± 0.65, p < 0.001) while free creatine concentrations were reduced to a similar degree (3.00 ± 0.50 vs. 3.74 ± 0.85, p < 0.001). Glutamate (5.33 ± 0.82 vs. 6.32 ± 1.12, p < 0.001), aspartate (3.39 ± 0.66 vs. 3.87 ± 1.19, p < 0.05), and GABA (0.92 ± 0.36 vs. 1.19 ± 0.41, p < 0.05) were also reduced, while taurine (1.39 ± 0.52 vs. 0.79 ± 0.61, p < 0.001) and glutathione (2.23 ± 0.41 vs. 2.09 ± 0.33, p < 0.05) were increased. Similar patterns were observed in other brain regions. These findings support that hypothermia improves energy homeostasis by decreasing the availability of excitatory neurotransmitters, and thereby, cellular energy demand.
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Affiliation(s)
- Jessica L Wisnowski
- Department of Radiology, Children's Hospital Los Angeles, Los Angeles, CA, USA Brain and Creativity Institute, University of Southern California, Los Angeles, CA, USA Department of Radiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA, USA Rudi Schulte Research Institute, Santa Barbara, CA, USA
| | - Tai-Wei Wu
- Department of Pediatrics, Division of Neonatology, Chang Gung Memorial Hospital, Taoyuan, Taiwan Department of Pediatrics, Division of Neonatology, Chang Gung University, Taoyuan, Taiwan
| | - Aaron J Reitman
- Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA Department of Pediatrics, Division of Neonatal Medicine, University of Southern California, Los Angeles, CA, USA
| | - Claire McLean
- Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA Department of Pediatrics, Division of Neonatal Medicine, University of Southern California, Los Angeles, CA, USA
| | - Philippe Friedlich
- Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA Department of Pediatrics, Division of Neonatal Medicine, University of Southern California, Los Angeles, CA, USA
| | - Douglas Vanderbilt
- Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA Department of Pediatrics, Developmental-Behavioral Pediatrics, University of Southern California, Los Angeles, CA, USA
| | - Eugenia Ho
- Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Los Angeles, CA, USA Department of Pediatrics, Division of Child Neurology, University of Southern California, Los Angeles, CA, USA
| | - Marvin D Nelson
- Department of Radiology, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Ashok Panigrahy
- Department of Radiology, Children's Hospital Los Angeles, Los Angeles, CA, USA Brain and Creativity Institute, University of Southern California, Los Angeles, CA, USA Department of Radiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA, USA
| | - Stefan Blüml
- Department of Radiology, Children's Hospital Los Angeles, Los Angeles, CA, USA Rudi Schulte Research Institute, Santa Barbara, CA, USA
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Abstract
Traumatic spinal cord injuries (SCIs) affect 1.3 million North Americans, producing devastating physical, social, and vocational impairment. Pathophysiologically, the initial mechanical trauma is followed by a significant secondary injury which includes local ischemia, pro-apoptotic signaling, release of cytotoxic factors, and inflammatory cell infiltration. Expedient delivery of medical and surgical care during this critical period can improve long-term functional outcomes, engendering the concept of "Time is Spine". We emphasize the importance of expeditious care while outlining the initial clinical and radiographic assessment of patients. Key evidence-based early interventions (surgical decompression, blood pressure augmentation, and methylprednisolone) are also reviewed, including findings of the landmark Surgical Timing in Acute Spinal Cord Injury Study (STASCIS). We then describe other neuroprotective approaches on the edge of translation such as the sodium-channel blocker riluzole, the anti-inflammatory minocycline, and therapeutic hypothermia. We also review promising neuroregenerative therapies that are likely to influence management practices over the next decade including chondroitinase, Rho-ROCK pathway inhibition, and bioengineered strategies. The importance of emerging neural stem cell therapies to remyelinate denuded axons and regenerate neural circuits is also discussed. Finally, we outline future directions for research and patient care.
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Affiliation(s)
- Christopher S Ahuja
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Allan R Martin
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Michael Fehlings
- Division of Neurosurgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; McEwen Centre for Regenerative Medicine, UHN, University of Toronto, Toronto, Ontario, Canada; Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Spine Program, University of Toronto, Toronto, Ontario, Canada; McLaughlin Center in Molecular Medicine, University of Toronto, Toronto, Ontario, Canada
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74
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Reduced cerebral blood flow and oxygen metabolism in extremely preterm neonates with low-grade germinal matrix- intraventricular hemorrhage. Sci Rep 2016; 6:25903. [PMID: 27181339 PMCID: PMC4867629 DOI: 10.1038/srep25903] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 04/25/2016] [Indexed: 01/24/2023] Open
Abstract
Low-grade germinal matrix-intraventricular hemorrhage (GM-IVH) is the most common complication in extremely premature neonates. The occurrence of GM-IVH is highly associated with hemodynamic instability in the premature brain, yet the long-term impact of low-grade GM-IVH on cerebral blood flow and neuronal health have not been fully investigated. We used an innovative combination of frequency-domain near infrared spectroscopy and diffuse correlation spectroscopy (FDNIRS-DCS) to measure cerebral oxygen saturation (SO2) and an index of cerebral blood flow (CBFi) at the infant’s bedside and compute an index of cerebral oxygen metabolism (CMRO2i). We enrolled twenty extremely low gestational age (ELGA) neonates (seven with low-grade GM-IVH) and monitored them weekly until they reached full-term equivalent age. During their hospital stay, we observed consistently lower CBFi and CMRO2i in ELGA neonates with low-grade GM-IVH compared to neonates without hemorrhages. Furthermore, lower CBFi and CMRO2i in the former group persists even after the resolution of the hemorrhage. In contrast, SO2 does not differ between groups. Thus, CBFi and CMRO2i may have better sensitivity than SO2 in detecting GM-IVH-related effects on infant brain development. FDNIRS-DCS methods may have clinical benefit for monitoring the evolution of GM-IVH, evaluating treatment response, and potentially predicting neurodevelopmental outcome.
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Birca A, Lortie A, Birca V, Decarie JC, Veilleux A, Gallagher A, Dehaes M, Lodygensky GA, Carmant L. Rewarming affects EEG background in term newborns with hypoxic–ischemic encephalopathy undergoing therapeutic hypothermia. Clin Neurophysiol 2016; 127:2087-94. [DOI: 10.1016/j.clinph.2015.12.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 12/09/2015] [Accepted: 12/12/2015] [Indexed: 11/15/2022]
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Forreider B, Pozivilko D, Kawaji Q, Geng X, Ding Y. Hibernation-like neuroprotection in stroke by attenuating brain metabolic dysfunction. Prog Neurobiol 2016; 157:174-187. [PMID: 26965388 DOI: 10.1016/j.pneurobio.2016.03.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 03/02/2016] [Accepted: 03/03/2016] [Indexed: 11/24/2022]
Abstract
Many mammalian species naturally undergo hibernation, a process that is associated with drastic changes in metabolism and systemic physiology. Their ability to retain an undamaged central nervous system during severely reduced cerebral blood flow has been studied for possible therapeutic application in human ischemic stroke. By inducing a less extreme 'hibernation-like' state, it has been hypothesized that similar neuroprotective effects reduce ischemia-mediated tissue damage in stroke patients. This manuscript includes reviews and evaluations of: (1) true hibernation, (2) hibernation-like state and its neuroprotective characteristics, (3) the preclinical and clinical methods for induction of artificial hibernation (i.e., therapeutic hypothermia, phenothiazine drugs, and ethanol), and (4) the mechanisms by which cerebral ischemia leads to tissue damage and how the above-mentioned induction methods function to inhibit those processes.
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Affiliation(s)
- Brian Forreider
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI, USA
| | - David Pozivilko
- Michigan State University College of Human Medicine, East Lansing, MI, USA
| | - Qingwen Kawaji
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI, USA
| | - Xiaokun Geng
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI, USA; China-America Institute of Neuroscience, Luhe Hospital, Capital Medical University, Beijing, China.
| | - Yuchuan Ding
- Department of Neurological Surgery, Wayne State University School of Medicine, Detroit, MI, USA; China-America Institute of Neuroscience, Luhe Hospital, Capital Medical University, Beijing, China.
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Govindan RB, Massaro A, Chang T, Vezina G, du Plessis A. A novel technique for quantitative bedside monitoring of neurovascular coupling. J Neurosci Methods 2015; 259:135-142. [PMID: 26684362 DOI: 10.1016/j.jneumeth.2015.11.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Revised: 11/24/2015] [Accepted: 11/27/2015] [Indexed: 11/28/2022]
Abstract
BACKGROUND There is no current method for continuous quantification of neurovascular coupling (NVC) in spontaneous brain activity. To fill this void, we propose a novel method to quantify NVC using electroencephalogram (EEG) and near-infrared spectroscopy (NIRS) data. NEW METHOD Since EEG and NIRS measure physiologic changes occurring at different time scales, we bring them into a common dynamical time frame (DTF). To achieve this, we partition both signals into one-second epochs and calculate the standard deviation of the EEG and the average value of the NIRS for each epoch. We then quantify the NVC by calculating spectral coherence between the two signals in the DTF. The resulting NVC will have a low resolution with all of its content localized below 1Hz. RESULTS After validating this framework on simulated data, we applied this approach to EEG and NIRS signals collected from four term infants undergoing therapeutic hypothermia for neonatal encephalopathy. Two of these infants showed no evidence of structural brain injury, and the other two died during the course of the therapy. The intact survivors showed emergence of NVC during hypothermia and/or after rewarming. In contrast, the two critically ill infants, who subsequently died, lacked this feature. COMPARISON WITH EXISTING METHODS Existing methods quantify NVC by averaging neurovascular signals based on certain events (for example seizure) in the EEG activity, whereas our approach quantifies coupling between spontaneous background EEG and NIRS. CONCLUSION Real-time continuous monitoring of NVC may be a promising physiologic signal for cerebral monitoring in future.
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Affiliation(s)
- R B Govindan
- Division of Fetal and Transitional Medicine, Fetal Medicine Institute, Children's National Health System, 111 Michigan Ave NW, Washington, DC 20010, USA.
| | - An Massaro
- Division of Neonatology, Children's National, 111 Michigan Ave NW, Washington, DC 20010, USA
| | - Taeun Chang
- Division of Neurology, Children's National, 111 Michigan Ave NW, Washington, DC 20010, USA
| | - Gilbert Vezina
- Division of Diagnostic Imaging and Radiology, Children's National, 111 Michigan Ave NW, Washington, DC 20010, USA
| | - Adré du Plessis
- Division of Fetal and Transitional Medicine, Fetal Medicine Institute, Children's National Health System, 111 Michigan Ave NW, Washington, DC 20010, USA
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Dehaes M, Cheng HH, Buckley EM, Lin PY, Ferradal S, Williams K, Vyas R, Hagan K, Wigmore D, McDavitt E, Soul JS, Franceschini MA, Newburger JW, Ellen Grant P. Perioperative cerebral hemodynamics and oxygen metabolism in neonates with single-ventricle physiology. BIOMEDICAL OPTICS EXPRESS 2015; 6:4749-67. [PMID: 26713191 PMCID: PMC4679251 DOI: 10.1364/boe.6.004749] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 11/01/2015] [Accepted: 11/03/2015] [Indexed: 05/03/2023]
Abstract
Congenital heart disease (CHD) patients are at risk for neurodevelopmental delay. The etiology of these delays is unclear, but abnormal prenatal cerebral maturation and postoperative hemodynamic instability likely play a role. A better understanding of these factors is needed to improve neurodevelopmental outcome. In this study, we used bedside frequency-domain near infrared spectroscopy (FDNIRS) and diffuse correlation spectroscopy (DCS) to assess cerebral hemodynamics and oxygen metabolism in neonates with single-ventricle (SV) CHD undergoing surgery and compared them to controls. Our goals were 1) to compare cerebral hemodynamics between unanesthetized SV and healthy neonates, and 2) to determine if FDNIRS-DCS could detect alterations in cerebral hemodynamics beyond cerebral hemoglobin oxygen saturation (SO 2). Eleven SV neonates were recruited and compared to 13 controls. Preoperatively, SV patients showed decreased cerebral blood flow (CBFi ), cerebral oxygen metabolism (CMRO 2i ) and SO 2; and increased oxygen extraction fraction (OEF) compared to controls. Compared to preoperative values, unstable postoperative SV patients had decreased CMRO 2i and CBFi , which returned to baseline when stable. However, SO 2 showed no difference between unstable and stable states. Preoperative SV neonates are flow-limited and show signs of impaired cerebral development compared to controls. FDNIRS-DCS shows potential to improve assessment of cerebral development and postoperative hemodynamics compared to SO 2 alone.
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Affiliation(s)
- Mathieu Dehaes
- Fetal Neonatal Neuroimaging & Developmental Science Center, Division of Newborn Medicine, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
- Mathieu Dehaes is currently at University of Montréal and Centre Hospitalier Universitaire Sainte-Justine, Montréal (QC), H3T 1C5,
Canada
- Mathieu Dehaes and Henry H. Cheng contributed equally to this work
| | - Henry H. Cheng
- Department of Cardiology, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
- Mathieu Dehaes and Henry H. Cheng contributed equally to this work
| | - Erin M. Buckley
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital & Harvard Medical School, Charlestown, MA 02129,
USA
- Erin M. Buckley is currently at Georgia Institute of Technology, Atlanta, GA 30322,
USA
| | - Pei-Yi Lin
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital & Harvard Medical School, Charlestown, MA 02129,
USA
| | - Silvina Ferradal
- Fetal Neonatal Neuroimaging & Developmental Science Center, Division of Newborn Medicine, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
| | - Kathryn Williams
- Department of Cardiology, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
| | - Rutvi Vyas
- Fetal Neonatal Neuroimaging & Developmental Science Center, Division of Newborn Medicine, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
| | - Katherine Hagan
- Fetal Neonatal Neuroimaging & Developmental Science Center, Division of Newborn Medicine, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
| | - Daniel Wigmore
- Department of Cardiology, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
| | - Erica McDavitt
- Department of Cardiology, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
| | - Janet S. Soul
- Department of Neurology, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
| | - Maria Angela Franceschini
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital & Harvard Medical School, Charlestown, MA 02129,
USA
| | - Jane W. Newburger
- Department of Cardiology, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
| | - P. Ellen Grant
- Fetal Neonatal Neuroimaging & Developmental Science Center, Division of Newborn Medicine, Boston Children’s Hospital & Harvard Medical School, Boston, MA 02115,
USA
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79
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Nakamura S, Koyano K, Jinnai W, Hamano S, Yasuda S, Konishi Y, Kuboi T, Kanenishi K, Nishida T, Kusaka T. Simultaneous measurement of cerebral hemoglobin oxygen saturation and blood volume in asphyxiated neonates by near-infrared time-resolved spectroscopy. Brain Dev 2015; 37:925-32. [PMID: 25975705 DOI: 10.1016/j.braindev.2015.04.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 03/26/2015] [Accepted: 04/05/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Hypoxic-ischemic encephalopathy (HIE) usually results in a poor clinical outcome even when treated with hypothermic therapy (HT). Early postnatal changes in cerebral blood oxygenation and hemodynamics may be critical determinants of brain injury and the efficacy of HT. OBJECTIVES We measured cerebral hemoglobin oxygen saturation (ScO2) and cerebral blood volume (CBV) by near-infrared time-resolved spectroscopy (TRS) in HT-treated and non-HT-treated neonatal HIE patients to assess the influence of these parameters on clinical outcome. METHODS We retrospectively compared ScO2, CBV, and clinical outcomes of 11 neonates with HIE: 5 were treated by HT (HT-treated; 33.5°C±0.5°C for 72h starting approximately 6h after delivery) and 6 were not (non-HT-treated). Both CBV and ScO2 were measured by TRS at 6, 24, 48, and 72h after birth. Magnetic resonance imaging (MRI) was performed 1-2weeks after birth to assess brain injury. RESULTS Five neonates had adverse outcomes (3 HT-treated, 2 non-HT-treated). Of these, 1 died within 3days of birth and 4 had abnormal MRI findings, including basal ganglia, white matter, and/or thalamic lesions. The other 6 neonates had normal MRI findings (favorable outcome). At 6h after birth, CBV was significantly higher in neonates with adverse outcomes compared with those with a favorable outcome. At 24h after birth, ScO2 was significantly higher in neonates with adverse outcomes. Furthermore, we found that combined CBV at 24h after birth plus ScO2 had the best predictive ability for neurological outcome: sensitivity, specificity, positive predictive value, and negative predictive value were all 100%. CONCLUSION Early postnatal CBV and ScO2 elevations were predictive of a poor outcome in HIE. Therefore, measuring combined CBV plus ScO2 at 24h after birth can allow more precise prediction of neurological outcome. Control of postnatal CBV and ScO2 is critical for effective HIE treatment.
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Affiliation(s)
- Shinji Nakamura
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Kosuke Koyano
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Wataru Jinnai
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Satoshi Hamano
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Saneyuki Yasuda
- Maternal Perinatal Center, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Yukihiko Konishi
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Toru Kuboi
- Department of Neonatology, Shikoku Medical Center for Children and Adults, Kagawa, Japan
| | - Kenji Kanenishi
- Maternal Perinatal Center, Faculty of Medicine, Kagawa University, Kagawa, Japan
| | - Tomoko Nishida
- Department of Education for Children with Special Needs, Faculty of Education, Kagawa University, Kagawa, Japan
| | - Takashi Kusaka
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Kagawa, Japan.
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Abstract
Spinal cord injury (SCI) is a major health problem and is associated with a diversity of neurological symptoms. Pathophysiologically, dysfunction after SCI results from the culmination of tissue damage produced both by the primary insult and a range of secondary injury mechanisms. The application of hypothermia has been demonstrated to be neuroprotective after SCI in both experimental and human studies. The myriad of protective mechanisms of hypothermia include the slowing down of metabolism, decreasing free radical generation, inhibiting excitotoxicity and apoptosis, ameliorating inflammation, preserving the blood spinal cord barrier, inhibiting astrogliosis, promoting angiogenesis, as well as decreasing axonal damage and encouraging neurogenesis. Hypothermia has also been combined with other interventions, such as antioxidants, anesthetics, alkalinization and cell transplantation for additional benefit. Although a large body of work has reported on the effectiveness of hypothermia as a neuroprotective approach after SCI and its application has been translated to the clinic, a number of questions still remain regarding its use, including the identification of hypothermia's therapeutic window, optimal duration and the most appropriate rewarming rate. In addition, it is necessary to investigate the neuroprotective effect of combining therapeutic hypothermia with other treatment strategies for putative synergies, particularly those involving neurorepair.
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Affiliation(s)
- Jiaqiong Wang
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, the Lois Pope Life Center, Locator code (R-48), PO BOX 016960, Miami, FL 33136, USA.
| | - Damien D Pearse
- The Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, the Lois Pope Life Center, Locator code (R-48), PO BOX 016960, Miami, FL 33136, USA.
- The Department of Neurological Surgery, University of Miami Miller School of Medicine, the Lois Pope Life Center, Locator code (R-48), PO BOX 016960, Miami, FL 33136, USA.
- The Neuroscience Program, University of Miami Miller School of Medicine, the Lois Pope Life Center, Locator code (R-48), PO BOX 016960, Miami, FL 33136, USA.
- The Interdisciplinary Stem Cell Institute, University of Miami Miller School of Medicine, the Lois Pope Life Center, Locator code (R-48), PO BOX 016960, Miami, FL 33136, USA.
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81
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Bakhsheshi MF, Diop M, Morrison LB, St. Lawrence K, Lee TY. Coupling of cerebral blood flow and oxygen consumption during hypothermia in newborn piglets as measured by time-resolved near-infrared spectroscopy: a pilot study. NEUROPHOTONICS 2015; 2:035006. [PMID: 26835481 PMCID: PMC4718069 DOI: 10.1117/1.nph.2.3.035006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 08/18/2015] [Indexed: 06/05/2023]
Abstract
Hypothermia (HT) is a potent neuroprotective therapy that is now widely used in following neurological emergencies, such as neonatal asphyxia. An important mechanism of HT-induced neuroprotection is attributed to the associated reduction in the cerebral metabolic rate of oxygen ([Formula: see text]). Since cerebral circulation and metabolism are tightly regulated, reduction in [Formula: see text] typically results in decreased cerebral blood flow (CBF); it is only under oxidative stress, e.g., hypoxia-ischemia, that oxygen extraction fraction (OEF) deviates from its basal value, which can lead to cerebral dysfunction. As such, it is critical to measure these key physiological parameters during therapeutic HT. This report investigates a noninvasive method of measuring the coupling of [Formula: see text] and CBF under HT and different anesthetic combinations of propofol/nitrous-oxide ([Formula: see text]) that may be used in clinical practice. Both CBF and [Formula: see text] decreased with decreasing temperature, but the OEF remained unchanged, which indicates a tight coupling of flow and metabolism under different anesthetics and over the mild HT temperature range (38°C to 33°C).
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Affiliation(s)
- Mohammad Fazel Bakhsheshi
- Lawson Health Research Institute, Imaging Program, 268 Grosvenor Street, London, Ontario N6A 4V2, Canada
- Robarts Research Institute, Imaging Research Laboratories, 1151 Richmond Street North, London, Ontario N6A 5B7, Canada
| | - Mamadou Diop
- Lawson Health Research Institute, Imaging Program, 268 Grosvenor Street, London, Ontario N6A 4V2, Canada
- Western University, Department of Medical Biophysics, London, Ontario N6A 5C1, Canada
| | - Laura B. Morrison
- Lawson Health Research Institute, Imaging Program, 268 Grosvenor Street, London, Ontario N6A 4V2, Canada
| | - Keith St. Lawrence
- Lawson Health Research Institute, Imaging Program, 268 Grosvenor Street, London, Ontario N6A 4V2, Canada
- Robarts Research Institute, Imaging Research Laboratories, 1151 Richmond Street North, London, Ontario N6A 5B7, Canada
- Western University, Department of Medical Biophysics, London, Ontario N6A 5C1, Canada
| | - Ting-Yim Lee
- Lawson Health Research Institute, Imaging Program, 268 Grosvenor Street, London, Ontario N6A 4V2, Canada
- Robarts Research Institute, Imaging Research Laboratories, 1151 Richmond Street North, London, Ontario N6A 5B7, Canada
- Western University, Department of Medical Biophysics, London, Ontario N6A 5C1, Canada
- Western University, Department of Medical Imaging, London, Ontario N6A 5W9, Canada
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82
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Abstract
Near-infrared spectroscopy (NIRS) offers non-invasive, in-vivo, real-time monitoring of tissue oxygenation. Changes in regional tissue oxygenation as detected by NIRS may reflect the delicate balance between oxygen delivery and consumption. Originally used predominantly to assess cerebral oxygenation and perfusion perioperatively during cardiac and neurosurgery, and following head trauma, NIRS has gained widespread popularity in many clinical settings in all age groups including neonates. However, more studies are required to establish the ability of NIRS monitoring to improve patient outcomes, especially in neonates. This review provides a comprehensive description of the use of NIRS in neonates.
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83
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Buckley EM, Patel SD, Miller BF, Franceschini MA, Vannucci SJ. In vivo Monitoring of Cerebral Hemodynamics in the Immature Rat: Effects of Hypoxia-Ischemia and Hypothermia. Dev Neurosci 2015; 37:407-16. [PMID: 26021410 DOI: 10.1159/000381704] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 03/16/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Neonatal hypoxic-ischemic (HI) encephalopathy occurs in 1-4 per 1,000 live term births and can cause devastating neurodevelopmental disabilities. Currently, therapeutic hypothermia (TH) is the only treatment with proven efficacy. Since TH is associated with decreased cerebral metabolism and cerebral blood flow (CBF), it is important to assess CBF at the bedside. Diffuse correlation spectroscopy (DCS) has emerged as a promising optical modality to noninvasively assess an index of CBF (CBFi) in both humans and animals. In this initial descriptive study, we employ DCS to monitor the evolution of CBFi following HI with or without TH in immature rats. We investigate potential relationships between CBF and subsequent cerebral damage. METHODS HI was induced on postnatal day 10 or 11 rat pups by right common carotid artery ligation followed by 60-70 min hypoxia (8% oxygen). After HI, the pups recovered for 4 h under hypothermia (HI-TH group, n = 23) or normothermia (HI-N group, n = 23). Bilateral measurements of hemispheric CBFi were made with DCS in unanesthetized animals at baseline, before HI, and 0, 1, 2, 3, 4, 5, and 24 h after HI. The animals were sacrificed at either 1 or 4 weeks, and brain injury was scored on an ordinal scale of 0-5 (0 = no injury). RESULTS Carotid ligation caused moderate bilateral decreases in CBFi. Following HI, an initial hyperemia was observed that was more prominent in the contralateral hemisphere. After initiation of TH, CBFi dropped significantly below baseline levels and remained reduced for the duration of TH. In contrast, CBFi in the HI-N group was not significantly decreased from baseline levels. Reductions in CBFi after 4 h of TH were not associated with reduced damage at 1 or 4 weeks. However, elevated ipsilateral CBFi and ipsilateral-to-contralateral CBFi ratios at 24 h were associated with worse outcome at 1 week after HI. CONCLUSIONS Both HI and TH alter CBFi, with significant differences in CBFi between hypothermic and normothermic groups after HI. CBFi may be a useful biomarker of subsequent cerebral damage.
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Affiliation(s)
- Erin M Buckley
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Mass., USA
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84
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Caldwell M, Hapuarachchi T, Highton D, Elwell C, Smith M, Tachtsidis I. BrainSignals Revisited: Simplifying a Computational Model of Cerebral Physiology. PLoS One 2015; 10:e0126695. [PMID: 25961297 PMCID: PMC4427507 DOI: 10.1371/journal.pone.0126695] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 04/07/2015] [Indexed: 02/06/2023] Open
Abstract
Multimodal monitoring of brain state is important both for the investigation of healthy cerebral physiology and to inform clinical decision making in conditions of injury and disease. Near-infrared spectroscopy is an instrument modality that allows non-invasive measurement of several physiological variables of clinical interest, notably haemoglobin oxygenation and the redox state of the metabolic enzyme cytochrome c oxidase. Interpreting such measurements requires the integration of multiple signals from different sources to try to understand the physiological states giving rise to them. We have previously published several computational models to assist with such interpretation. Like many models in the realm of Systems Biology, these are complex and dependent on many parameters that can be difficult or impossible to measure precisely. Taking one such model, BrainSignals, as a starting point, we have developed several variant models in which specific regions of complexity are substituted with much simpler linear approximations. We demonstrate that model behaviour can be maintained whilst achieving a significant reduction in complexity, provided that the linearity assumptions hold. The simplified models have been tested for applicability with simulated data and experimental data from healthy adults undergoing a hypercapnia challenge, but relevance to different physiological and pathophysiological conditions will require specific testing. In conditions where the simplified models are applicable, their greater efficiency has potential to allow their use at the bedside to help interpret clinical data in near real-time.
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Affiliation(s)
- Matthew Caldwell
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Tharindi Hapuarachchi
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
- Centre for Mathematics and Physics in the Life Sciences and Experimental Biology, University College London, London, UK
| | - David Highton
- Neurocritical Care Unit, University College Hospitals, London, UK
| | - Clare Elwell
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Martin Smith
- Neurocritical Care Unit, University College Hospitals, London, UK
| | - Ilias Tachtsidis
- Department of Medical Physics and Biomedical Engineering, University College London, London, UK
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85
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Liu P, Chalak LF, Lu H. Non-invasive assessment of neonatal brain oxygen metabolism: A review of newly available techniques. Early Hum Dev 2014; 90:695-701. [PMID: 25028136 PMCID: PMC4170025 DOI: 10.1016/j.earlhumdev.2014.06.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 06/23/2014] [Indexed: 11/28/2022]
Abstract
Because oxidative metabolism is the primary form of energy production in the brain, the amount of oxygen consumed by the brain, denoted by a physiological parameter termed cerebral metabolic rate of oxygen (CMRO2), represents a key marker for tissue viability and brain function. Quantitative assessment of cerebral oxygen metabolism in the neonate may provide an important marker in better understanding normal brain development and in making diagnosis and treatment decisions in neonatal brain injuries. Measurement of CMRO2 in humans has been a challenging task, particularly in neonates. Recently, several promising techniques have been proposed to quantify neonatal CMRO2 and the purpose of this article is to provide a technical review of these techniques. Among these, we will focus the review on the NIRS optic based methods and MRI methods which are non-invasive, have been applied in normal and sick newborns and show great potentials. Potential clinical prospects of CMRO2 techniques are discussed in the context of their advantages, challenges and limitations.
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Affiliation(s)
- Peiying Liu
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, United States.
| | - Lina F Chalak
- Depart of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, United States.
| | - Hanzhang Lu
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, United States.
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86
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Greisen G. Cerebral blood flow and oxygenation in infants after birth asphyxia. Clinically useful information? Early Hum Dev 2014; 90:703-5. [PMID: 25028135 DOI: 10.1016/j.earlhumdev.2014.06.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 06/23/2014] [Indexed: 11/18/2022]
Abstract
The term 'luxury perfusion' was coined nearly 50 years ago after observation of bright-red blood in the cerebral veins of adults with various brain pathologies. The bright-red blood represents decreased oxygen extraction and hence the perfusion is 'luxurious' compared to oxygen needs. Gradual loss of cellular energy charge during the hours following severe birth asphyxia was observed twenty years later by sequential cranial magnetic resonance spectroscopy. This led to the concept of delayed energy failure that is linked to mitochondrial dysfunction and apoptotic cell death. Abnormally increased perfusion and lack of normal cerebral blood flow regulation are also typically present, but whether the perfusion abnormalities at this secondary stage are detrimental, beneficial, or a mere epiphenomenon remains elusive. In contrast, incomplete reoxygenation of the brain during and following resuscitation is likely to compromise outcome. The clinical value of cerebral oximetry in this context can only be examined in a randomised clinical trial.
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Affiliation(s)
- Gorm Greisen
- Department of Neonatology, Rigshospitalet and University of Copenhagen, Denmark
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87
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Bale G, Mitra S, Meek J, Robertson N, Tachtsidis I. A new broadband near-infrared spectroscopy system for in-vivo measurements of cerebral cytochrome-c-oxidase changes in neonatal brain injury. BIOMEDICAL OPTICS EXPRESS 2014; 5:3450-66. [PMID: 25360364 PMCID: PMC4206316 DOI: 10.1364/boe.5.003450] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 08/15/2014] [Accepted: 08/22/2014] [Indexed: 05/02/2023]
Abstract
We present a novel lens-based broadband near-infrared spectroscopy system to simultaneously measure cerebral changes in tissue oxygenation and haemodynamics via estimation of the changes in haemoglobin concentration; in addition to oxygen utilization via the measurement of the oxidation state of cytochrome-c-oxidase (CCO). We demonstrate the use of the system in a cohort of 6 newborn infants with neonatal encephalopathy in the Neonatal Intensive Care Unit for continuous measurement periods of up to 5 days. NIRS data was collected from above the frontal lobe on the left and right hemispheres simultaneously with systemic data to allow multimodal data analysis. This allowed us to study the NIRS variables in response to global pathophysiological events and we focused our analysis to spontaneous oxygen desaturations. We identified changes from the NIRS variables during 236 oxygen desaturations from over 212 hours of data with a change from the baseline to nadir of -12 ± 3%. There was a consistent negative change in the Δ[HbD] (= oxygenated - deoxygenated haemoglobin) and Δ[oxCCO] measurements, mean decreases were 3.0 ± 1.7μM and 0.22 ± 0.11μM, and a positive change in the Δ[HbT] (= oxygenated + deoxygenated haemoglobin) measurements across all subjects, mean increase was 0.85 ± 0.58μM. We have shown with a feasibility study that the relationship between haemoglobin oxygenation changes and CCO oxidation changes during these desaturation events was significantly associated with a magnetic resonance spectroscopy (MRS)-measured biomarker of injury severity (r = 0.91, p<0.01).
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Affiliation(s)
- Gemma Bale
- Department of Medical Physics and Bioengineering, Malet Place Engineering Building, University College London, UK
| | - Subhabrata Mitra
- Institute for Women’s Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK
| | - Judith Meek
- Institute for Women’s Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK
| | - Nicola Robertson
- Institute for Women’s Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK
| | - Ilias Tachtsidis
- Department of Medical Physics and Bioengineering, Malet Place Engineering Building, University College London, UK
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88
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Nnorom CC, Davis C, Fedinec AL, Howell K, Jaggar JH, Parfenova H, Pourcyrous M, Leffler CW. Contributions of KATP and KCa channels to cerebral arteriolar dilation to hypercapnia in neonatal brain. Physiol Rep 2014; 2:2/8/e12127. [PMID: 25168876 PMCID: PMC4246596 DOI: 10.14814/phy2.12127] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Mechanisms by which Pco2 controls cerebral vascular tone remain uncertain. We hypothesize that potassium channel activation contributes to the neonatal cerebrovascular dilation in response to increases in Paco2. To test this hypothesis, experiments were performed on newborn pigs with surgically implanted, closed cranial windows. Hypercapnia was induced by ventilation with elevated Pco2 gas in the absence and presence of the KATP channel inhibitor, glibenclamide and/or the KCa channel inhibitor, paxillin. Dilations to pinacidil, a selective KATP channel activator, without and with glibenclamide, were used to evaluate the efficacy of KATP channel inhibition. Dilations to NS1619, a selective KCa channel activator, without and with paxillin, were used to evaluate the efficacy of KCa channel inhibition. Cerebrovascular responses to the KATP and KCa channel activators, pinacidil and NS1619, respectively, cAMP‐dependent dilator, isoproterenol, and cGMP‐dependent dilator, sodium nitroprusside (SNP), were used to evaluate the selectivity of glibenclamide and paxillin. Glibenclamide blocked dilation to pinacidil, but did not inhibit dilations to NS1619, isoproterenol, or SNP. Glibenclamide prior to hypercapnia decreased mean pial arteriole dilation ~60%. Glibenclamide treatment during hypercapnia constricted arterioles ~35%. The level of hypercapnia, Paco2 between 50 and 75 mmHg, did not appear to be involved in efficacy of glibenclamide in blocking dilation to Paco2. Similarly to glibenclamide and KATP channel inhibition, paxillin blocked dilation to the KCa channel agonist, NS1619, and attenuated, but did not block, arteriolar dilation to hypercapnia. Treatment with both glibenclamide and paxillin abolished dilation to hypercapnia. Therefore, either glibenclamide or paxillin that block dilation to their channel agonists, pinacidil or NS1619, respectively, only partially inhibit dilation to hypercapnia. Block of both KATP and KCa channels completely prevent dilation hypercapnia. These data suggest hypercapnia activates both KATP and KCa channels leading to cerebral arteriolar dilation in newborn pigs. Mechanisms by which Pco2 controls vascular tone remain uncertain. We hypothesize KATP and KCa channel activation contributes to the neonatal cerebrovascular dilation in response to increases in Paco2. Presented data support this hypothesis.
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Affiliation(s)
- Chukwuma C Nnorom
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Corinne Davis
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Alexander L Fedinec
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Khadesia Howell
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Jonathan H Jaggar
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Helena Parfenova
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Massroor Pourcyrous
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Charles W Leffler
- Departments of Physiology and Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
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89
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Demel A, Wolf M, Poets CF, Franz AR. Effect of different assumptions for brain water content on absolute measures of cerebral oxygenation determined by frequency-domain near-infrared spectroscopy in preterm infants: an observational study. BMC Pediatr 2014; 14:206. [PMID: 25138045 PMCID: PMC4144695 DOI: 10.1186/1471-2431-14-206] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 08/12/2014] [Indexed: 11/10/2022] Open
Abstract
Background Brain-water content (BWC) decreases with maturation of the brain and potentially affects parameters of cerebral oxygenation determined by near-infrared spectroscopy (NIRS). Most commercially available devices do not take these maturational changes into account. The aim of this study was to determine the effect of different assumptions for BWC on parameters of cerebral oxygenation in preterm infants. Methods Concentrations of oxy-, deoxy- and total hemoglobin and regional cerebral oxygen saturation (rcStO2) were calculated based on absolute coefficients of absorption and scattering determined by multi-distance Frequency-Domain-NIRS assuming BWCs of 75-95%, which may be encountered in newborn infants depending on gestational and postnatal age. Results This range of BWC gave rise to a linear modification of the assessed NIRS parameters with a maximum change of 10%. This may result in an absolute overestimation of rcStO2 by (median (range)) 4 (1–8)%, if the calculation is based on the lowest BWC (75%) in an extremely preterm infant with an anticipated BWC of 95%. Conclusion Clinicians wishing to rely on parameters of cerebral oxygenation determined by NIRS should consider that maturational changes in BWC not taken into account by most devices may result in a deviation of cerebral oxygenation readings by up to 8% from the correct value.
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Affiliation(s)
- Anja Demel
- Department of Neonatology, University Children's Hospital Tuebingen, Tuebingen, Germany.
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90
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Buckley EM, Parthasarathy AB, Grant PE, Yodh AG, Franceschini MA. Diffuse correlation spectroscopy for measurement of cerebral blood flow: future prospects. NEUROPHOTONICS 2014; 1:011009. [PMID: 25593978 PMCID: PMC4292799 DOI: 10.1117/1.nph.1.1.011009] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Diffuse correlation spectroscopy (DCS) is an emerging optical modality used to measure cortical cerebral blood flow. This outlook presents a brief overview of the technology, summarizing the advantages and limitations of the method, and describing its recent applications to animal, adult, and infant cohorts. At last, the paper highlights future applications where DCS may play a pivotal role individualizing patient management and enhancing our understanding of neurovascular coupling, activation, and brain development.
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Affiliation(s)
- Erin M. Buckley
- Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts 02129
- Address all correspondence to: Erin M. Buckley,
| | - Ashwin B. Parthasarathy
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania 19104
| | - P. Ellen Grant
- Boston Children’s Hospital, Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston, Massachusetts 02115
| | - Arjun G. Yodh
- University of Pennsylvania, Department of Physics and Astronomy, Philadelphia, Pennsylvania 19104
| | - Maria Angela Franceschini
- Massachusetts General Hospital, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Charlestown, Massachusetts 02129
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