Biomaterial Database

MRI diffusion-weighted spectroscopy of reversible and irreversible ischemic injury following closed head injury. 1997

P Barzó, and A Marmarou, and P Fatouros, and J Ito, and F Corwin

Division of Neurosurgery, Medical College of Virginia, Richmond, USA.

The objective of this study was to detect the threshold between reversible and irreversible secondary insult of hypoxia and hypotension following closed head injury as measured by MRI. Adult Sprague rats were separated into 3 groups: I: Sham (n = 6), II: Trauma and hypoxia coupled with mild hypotension of 40-50 mmHg (n = 6), III: Trauma and hypoxia coupled with severe hypotension of 30-40 mmHg (n = 6). The measurement of brain water content (BWC) was based on T1, whereas the differentiation between reversible and irreversible secondary insult on the measurement apparent diffusion coefficient (ADC). The ADCs in both trauma and secondary insult groups decreased rapidly from a control level of 0.68 +/- 0.5 x 10(-3) to significantly different minimum levels of 0.52 +/- 0.5 x 10(-3) in Group II and 0.42 +/- 0.5 x 10(-3) mm2/second in Group III at 30 minutes. In Group II rats there was a complete recovery in ADC as well as in their clinical conditions, whereas ADC in Group III rats remained at the minimum level and the animals were brain dead. The BWC was also significantly different at four hours post injury (Group II: 80.3 +/- 0.7%, Group III: 81.8 +/- 0.8%). The data lead the authors to suggest that the threshold between reversible and irreversible posttraumatic secondary insult is very narrow, and the measurement of ADC can provide information that will enable the clinician to identify critical threshold beyond which recovery is not possible.

UI	MeSH Term	Description	Entries
D007022	Hypotension	Abnormally low BLOOD PRESSURE that can result in inadequate blood flow to the brain and other vital organs. Common symptom is DIZZINESS but greater negative impacts on the body occur when there is prolonged depravation of oxygen and nutrients.	Blood Pressure, Low,Hypotension, Vascular,Low Blood Pressure,Vascular Hypotension
D008279	Magnetic Resonance Imaging	Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.	Chemical Shift Imaging,MR Tomography,MRI Scans,MRI, Functional,Magnetic Resonance Image,Magnetic Resonance Imaging, Functional,Magnetization Transfer Contrast Imaging,NMR Imaging,NMR Tomography,Tomography, NMR,Tomography, Proton Spin,fMRI,Functional Magnetic Resonance Imaging,Imaging, Chemical Shift,Proton Spin Tomography,Spin Echo Imaging,Steady-State Free Precession MRI,Tomography, MR,Zeugmatography,Chemical Shift Imagings,Echo Imaging, Spin,Echo Imagings, Spin,Functional MRI,Functional MRIs,Image, Magnetic Resonance,Imaging, Magnetic Resonance,Imaging, NMR,Imaging, Spin Echo,Imagings, Chemical Shift,Imagings, Spin Echo,MRI Scan,MRIs, Functional,Magnetic Resonance Images,Resonance Image, Magnetic,Scan, MRI,Scans, MRI,Shift Imaging, Chemical,Shift Imagings, Chemical,Spin Echo Imagings,Steady State Free Precession MRI
D008297	Male		Males
D001834	Body Water	Fluids composed mainly of water found within the body.	Water, Body
D002534	Hypoxia, Brain	A reduction in brain oxygen supply due to ANOXEMIA (a reduced amount of oxygen being carried in the blood by HEMOGLOBIN), or to a restriction of the blood supply to the brain, or both. Severe hypoxia is referred to as anoxia and is a relatively common cause of injury to the central nervous system. Prolonged brain anoxia may lead to BRAIN DEATH or a PERSISTENT VEGETATIVE STATE. Histologically, this condition is characterized by neuronal loss which is most prominent in the HIPPOCAMPUS; GLOBUS PALLIDUS; CEREBELLUM; and inferior olives.	Anoxia, Brain,Anoxic Encephalopathy,Brain Hypoxia,Cerebral Anoxia,Encephalopathy, Hypoxic,Hypoxic Encephalopathy,Anoxia, Cerebral,Anoxic Brain Damage,Brain Anoxia,Cerebral Hypoxia,Hypoxia, Cerebral,Hypoxic Brain Damage,Anoxic Encephalopathies,Brain Damage, Anoxic,Brain Damage, Hypoxic,Damage, Anoxic Brain,Damage, Hypoxic Brain,Encephalopathies, Anoxic,Encephalopathies, Hypoxic,Encephalopathy, Anoxic,Hypoxic Encephalopathies
D002545	Brain Ischemia	Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia (HYPOXIA, BRAIN). Prolonged ischemia is associated with BRAIN INFARCTION.	Cerebral Ischemia,Ischemic Encephalopathy,Encephalopathy, Ischemic,Ischemia, Cerebral,Brain Ischemias,Cerebral Ischemias,Ischemia, Brain,Ischemias, Cerebral,Ischemic Encephalopathies
D002546	Ischemic Attack, Transient	Brief reversible episodes of focal, nonconvulsive ischemic dysfunction of the brain having a duration of less than 24 hours, and usually less than one hour, caused by transient thrombotic or embolic blood vessel occlusion or stenosis. Events may be classified by arterial distribution, temporal pattern, or etiology (e.g., embolic vs. thrombotic). (From Adams et al., Principles of Neurology, 6th ed, pp814-6)	Brain Stem Ischemia, Transient,Cerebral Ischemia, Transient,Crescendo Transient Ischemic Attacks,Transient Ischemic Attack,Anterior Circulation Transient Ischemic Attack,Brain Stem Transient Ischemic Attack,Brain TIA,Brainstem Ischemia, Transient,Brainstem Transient Ischemic Attack,Carotid Circulation Transient Ischemic Attack,Posterior Circulation Transient Ischemic Attack,TIA (Transient Ischemic Attack),Transient Ischemic Attack, Anterior Circulation,Transient Ischemic Attack, Brain Stem,Transient Ischemic Attack, Brainstem,Transient Ischemic Attack, Carotid Circulation,Transient Ischemic Attack, Posterior Circulation,Transient Ischemic Attack, Vertebrobasilar Circulation,Transient Ischemic Attacks, Crescendo,Vertebrobasilar Circulation Transient Ischemic Attack,Attack, Transient Ischemic,Attacks, Transient Ischemic,Brainstem Ischemias, Transient,Cerebral Ischemias, Transient,Ischemia, Transient Brainstem,Ischemia, Transient Cerebral,Ischemias, Transient Brainstem,Ischemias, Transient Cerebral,Ischemic Attacks, Transient,TIA, Brain,TIAs (Transient Ischemic Attack),Transient Brainstem Ischemia,Transient Cerebral Ischemia,Transient Cerebral Ischemias,Transient Ischemic Attacks
D004058	Diffusion	The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.	Diffusions
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D016489	Head Injuries, Closed	Traumatic injuries to the cranium where the integrity of the skull is not compromised and no bone fragments or other objects penetrate the skull and DURA MATER. This frequently results in mechanical injury being transmitted to intracranial structures which may produce TRAUMATIC BRAIN INJURIES, hemorrhage, or CRANIAL NERVE INJURIES. (From Rowland, Merritt's Textbook of Neurology, 9th ed, p417)	Head Injuries, Nonpenetrating,Head Trauma, Closed,Closed Head Injuries,Head Injury, Blunt,Head Injury, Nonpenetrating,Injuries, Closed Head,Blunt Head Injuries,Blunt Head Injury,Closed Head Injury,Closed Head Trauma,Closed Head Traumas,Head Injuries, Blunt,Head Injury, Closed,Head Traumas, Closed,Nonpenetrating Head Injuries,Nonpenetrating Head Injury