Abstract
A method for determining the time elapsed after a cerebrovascular accident by exanaination of the cerebrospinal fluid (CSF) is described. Hemorrhagic intracranial trauma was simulated in dogs by injecting blood into the subarachnoid space. Daily samples of cerebrospinal fluid were gathered during the subsequent 14 days, and the concentrations of oxyhemoglobin and bilirubin were measured using spectrophotometric methods. The hemoglobin coefficient (HC), defined as the ratio of the oxyhemoglobin concentration to the sum of the concentrations of the cerebrospinal fluid pigments, and the hemoglobin-bilirubin index (HBI), the ratio of the oxyhemoglobin and the bilirubin concentrations, are found to permit accurate calculation of the time elapsed after the hemorrhage.