Biomaterial Database

Somatosensory evoked potentials as a measure of experimental cerebral ischemia. 1985

K L Meyer, and R J Dempsey, and M W Roy, and D L Donaldson

Somatosensory evoked potentials (SEP's) reflect the integrity of the central neuronal pathway, and as such may be used to assess function that remains during a variety of cerebral insults. To evaluate the natural history and utility of SEP's during experimental cerebral ischemia and infarction, SEP's were measured in 17 adult cats at 24 hours and 1 hour prior to right middle cerebral artery (MCA) occlusion, and again immediately afterward and at either 6 hours (five cats) or 24 hours (six cats) post-occlusion. Before occlusion of the right MCA, the SEP's were identical in the right and left hemispheres. After occlusion, there was a significant slowing of the interpeak latency of the first positive peak (P1) in the right hemisphere (3.53 +/- 0.6 msec before compared to 3.99 +/- 0.6 msec after occlusion, p less than 0.001). Maximal slowing in right hemisphere P1 latency was seen in those animals in which the stroke extended into the thalamus (4.38 +/- 0.1 msec). This was significantly slower than left hemisphere values (3.92 +/- 0.32 msec, p less than 0.01). The ipsilateral cortical components of the SEP's, the second positive peak (P2), and the major negative deflection (MN) were slowed in all cats immediately after right MCA occlusion compared to preocclusion measurements (p less than 0.001). Severe infarcts in the mid-suprasylvian and posterior ectosylvian gyri (including the somatosensory cortex) resulted in a greater slowing of the latency of MN compared to less severe infarcts in that region (20.6 +/- 3.9 msec versus 16.4 +/- 1.1 msec, p less than 0.05). There was a precipitous decrease in the amplitude or voltage of the ipsilateral P2-MN complex immediately after occlusion (5.32 +/- 0.4 microV before compared to 0.98 +/- 0.3 microV after occlusion, p less than 0.001). Therefore, the central latencies and cortical amplitudes of the SEP's are sensitive experimental tools as indicators of the onset and extent of a cerebral ischemic insult.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D001929	Brain Edema	Increased intracellular or extracellular fluid in brain tissue. Cytotoxic brain edema (swelling due to increased intracellular fluid) is indicative of a disturbance in cell metabolism, and is commonly associated with hypoxic or ischemic injuries (see HYPOXIA, BRAIN). An increase in extracellular fluid may be caused by increased brain capillary permeability (vasogenic edema), an osmotic gradient, local blockages in interstitial fluid pathways, or by obstruction of CSF flow (e.g., obstructive HYDROCEPHALUS). (From Childs Nerv Syst 1992 Sep; 8(6):301-6)	Brain Swelling,Cerebral Edema,Cytotoxic Brain Edema,Intracranial Edema,Vasogenic Cerebral Edema,Cerebral Edema, Cytotoxic,Cerebral Edema, Vasogenic,Cytotoxic Cerebral Edema,Vasogenic Brain Edema,Brain Edema, Cytotoxic,Brain Edema, Vasogenic,Brain Swellings,Cerebral Edemas, Vasogenic,Edema, Brain,Edema, Cerebral,Edema, Cytotoxic Brain,Edema, Cytotoxic Cerebral,Edema, Intracranial,Edema, Vasogenic Brain,Edema, Vasogenic Cerebral,Swelling, Brain
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D002539	Cerebral Arterial Diseases	Pathological conditions of intracranial ARTERIES supplying the CEREBRUM. These diseases often are due to abnormalities or pathological processes in the ANTERIOR CEREBRAL ARTERY; MIDDLE CEREBRAL ARTERY; and POSTERIOR CEREBRAL ARTERY.	Cerebral Artery Diseases,Arterial Diseases, Cerebral,Arterial Disease, Cerebral,Artery Disease, Cerebral,Artery Diseases, Cerebral,Cerebral Arterial Disease,Cerebral Artery Disease,Disease, Cerebral Arterial,Disease, Cerebral Artery,Diseases, Cerebral Arterial,Diseases, Cerebral Artery
D002544	Cerebral Infarction	The formation of an area of NECROSIS in the CEREBRUM caused by an insufficiency of arterial or venous blood flow. Infarcts of the cerebrum are generally classified by hemisphere (i.e., left vs. right), lobe (e.g., frontal lobe infarction), arterial distribution (e.g., INFARCTION, ANTERIOR CEREBRAL ARTERY), and etiology (e.g., embolic infarction).	Anterior Choroidal Artery Infarction,Cerebral Infarct,Infarction, Cerebral,Posterior Choroidal Artery Infarction,Subcortical Infarction,Cerebral Infarction, Left Hemisphere,Cerebral Infarction, Right Hemisphere,Cerebral, Left Hemisphere, Infarction,Cerebral, Right Hemisphere, Infarction,Infarction, Cerebral, Left Hemisphere,Infarction, Cerebral, Right Hemisphere,Infarction, Left Hemisphere, Cerebral,Infarction, Right Hemisphere, Cerebral,Left Hemisphere, Cerebral Infarction,Left Hemisphere, Infarction, Cerebral,Right Hemisphere, Cerebral Infarction,Right Hemisphere, Infarction, Cerebral,Cerebral Infarctions,Cerebral Infarcts,Infarct, Cerebral,Infarction, Subcortical,Infarctions, Cerebral,Infarctions, Subcortical,Infarcts, Cerebral,Subcortical Infarctions
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
D002561	Cerebrovascular Disorders	A spectrum of pathological conditions of impaired blood flow in the brain. They can involve vessels (ARTERIES or VEINS) in the CEREBRUM, the CEREBELLUM, and the BRAIN STEM. Major categories include INTRACRANIAL ARTERIOVENOUS MALFORMATIONS; BRAIN ISCHEMIA; CEREBRAL HEMORRHAGE; and others.	Brain Vascular Disorders,Intracranial Vascular Disorders,Vascular Diseases, Intracranial,Cerebrovascular Diseases,Cerebrovascular Insufficiency,Cerebrovascular Occlusion,Brain Vascular Disorder,Cerebrovascular Disease,Cerebrovascular Disorder,Cerebrovascular Insufficiencies,Cerebrovascular Occlusions,Disease, Cerebrovascular,Diseases, Cerebrovascular,Insufficiencies, Cerebrovascular,Insufficiency, Cerebrovascular,Intracranial Vascular Disease,Intracranial Vascular Diseases,Intracranial Vascular Disorder,Occlusion, Cerebrovascular,Occlusions, Cerebrovascular,Vascular Disease, Intracranial,Vascular Disorder, Brain,Vascular Disorder, Intracranial,Vascular Disorders, Brain,Vascular Disorders, Intracranial
D004292	Dominance, Cerebral	Dominance of one cerebral hemisphere over the other in cerebral functions.	Cerebral Dominance,Hemispheric Specialization,Dominances, Cerebral,Specialization, Hemispheric
D005073	Evoked Potentials, Somatosensory	The electric response evoked in the CEREBRAL CORTEX by stimulation along AFFERENT PATHWAYS from PERIPHERAL NERVES to CEREBRUM.	Somatosensory Evoked Potentials,Evoked Potential, Somatosensory,Somatosensory Evoked Potential
D005260	Female		Females