Effect of goreisan for chronic subdural hematoma

Abstract

Goreisan has been shown to prevent the recurrence of chronic subdural hematoma (CSDH); however, its therapeutic effect has not been discussed from the viewpoint of Kampo medicine. In this case report, we present our experience with a patient in whom goreisan treatment effectively prevented the recurrence of CSDH; a discussion of the mechanism of action presented. An 81-year-old man was brought to our hospital with altered consciousness and right hemipasis. Head computed tomography (CT) revealed bilateral CSDH. Burrhole surgery was performed; postoperatively, goreisan therapy was administered to prevent the recurrence of symptoms. Head CT at 1 month postoperatively revealed no recurrence of left CSDH, and right CSDH was ameliorated. The pathogenesis of CSDH is attributed to the extravasation of blood components from the outer membrane of the hematoma owing to hyperfibrinolysis or the influx of cerebro­spinal fluid due to the osmotic pressure gradient across the hematoma membrane. In Kampo medicine, hematoma is regarded as blood stagnation. Moreover, the uneven distribution of cerebrospinal fluid, which is regarded as a fluid according to Kampo medicine, and the osmotic pressure gradient are both involved in fluid retention. Preoperative head CT showed the delineation of low- and high-density areas in the hematoma. In other words, imaging revealed the presence of both red fluids (ketsu) and transparent fluids (sui), which suggests fluid retention. The fluid-disinhibiting drug goreisan appears to be an effective remedy for the symptom of fluid retention.