Spreading depolarization occurs in repeating, recognizable, patient-specific patterns after human brain injury

Background and Objective: Electrocorticographic (ECoG) measurement of spreading depolarization (SD) has led to significant advances in understanding of injury progression in neuro ICU patients.  However, SD can be difficult to recognize in ECoG regions with high artifact. Heuristics for ECoG analysis within these regions would be highly valuable.Methods: Patients requiring craniotomy following subarachnoid hemorrhage, malignant hemispheric stroke, or traumatic brain injury were enrolled in this study. ECoG leads were placed intraoperatively and scoring of SDs was completed twice; once using traditional criteria and again with the intention of finding SD patterns. Utilizing covariance structures, graphical overlay and various measures surrounding DC shift, SDs were evaluated for patterns.Results: SD patterns were consistently observed and were unique to each patient and lead placement. No more than five different patterns were noted for any given patient, and statistical analysis utilizing covariance structures revealed high intra-pattern consistency.Conclusion: This validation of internal patient specific patterns offers more insight into ECoG readings of high artifact regions. This, in addition to traditional SD scoring heuristics, offers another scoring tool for the neuro-ICU care of patient experiencing SD. Furthermore, description of neurologic disease by its SD patterns may offer a new direction for precision medicine.