Case Number 114089 - Non-invasive Detection of Spreading Depolarizations
Contact: Jill Uhl
Description: Dr. Jed Hartings has discovered the unexpected ability to detect spreading depolarizations of the cerebral cortex using non-invasive scalp electroencephalography (sEEG). Spreading depolarizations are pathophysiologic waves that occur spontaneously in the brain following neurological insults such as brain trauma or stroke. They are believed to cause further brain damage. In patients with aneurysmal subarachnoid hemorrhage clusters of spreading depolarizations are associated with delayed cerebral ischemia characterized by new neurological deficits and cortical infarcts. In traumatic brain injury (TBI) the occurrence of spreading depolarizations is an independent predictor of poor clinical outcomes.
Accumulating evidence suggests that monitoring of spreading depolarizations could have a similar value in acute brain injury as electrophysiological tools have in epilepsy and cardiology. However, the current gold standard method to detect spreading depolarizations in patients is with invasive intracranial electroencephalography (icEEG). This requires surgery to open a patient’s skull in order to place electrode strips on the cortical surface and subsequently performing continuous icEEG monitoring during intensive care patient management. This present requirement for invasive procedures has limited the application of such icEEG monitoring of spreading depolarizations to a small minority of patients often in a research setting.
Dr. Hartings research in an observational study with eighteen TBI patients has identified a unique invention of three methods to identify spreading depolarizations non-invasively using sEEG recordings. These methods are clinically complimentary. They include: 1) detection of spreading depolarizations as suppressions of pathologic high-amplitude delta activity, 2) shifts in direct current potential and 3) observing the spread delay in the time of occurrence of changes in delta activity suppression or direct current potential shifts from one head area to another. Detection of spreading depolarizations in patients using any of these non-invasive methods may be useful to identify causes of neurological symptoms, to guide treatments and to improve clinical outcomes. A validated sEEG method for detection of spreading depolarization would provide the first non-invasive method for routine bedside monitoring of a neuronal pathomechanism and marker of lesion development with broad application to TBI and hemorrhagic and ischemic stroke.
According to the Centers for Disease Control and Prevention (CDC) about 2.5 million TBI’s occur either as an isolated injury or along with other injuries each year. More than 50,000 people die from TBI injury. The cost of TBI to society in the USA is estimated to be between $40-$75 billion. Every year nearly 800,000 people in the USA have a stroke of which 610,000 are first or new strokes and 87% are ischemic strokes. About 130,000 Americans die of stroke every year. The direct and indirect cost of stroke in the USA in 2010 was $36.5 billion. The global brain monitoring device market was worth slightly more than $1.0 billion in 2012 and is expected to grow nearly 9% yearly. This invention would participate in this device market.
U.S. Provisional Patent Application 62/018,909 filed on June 30, 2014
U.S. Provisional Patent Application 62/035,756 filed on August 11, 2014
J.A. Hartings, et. al.; Annals of Neurology 2014;76:681-694 "Spreading Depression in Continuous Electrocephalography of Brain Trauma"