A Prospective Randomized Study on the Preventive Effect of Japanese Herbal Kampo Medicine Goreisan for Recurrence of Chronic Subdural Hematoma

Abstract

Although the recurrence of chronic subdural hematoma (CSDH) after surgical treatment significantly affects the patients' quality of life, the recurrence rate has not improved in decades. Goreisan, a Japanese herbal Kampo medicine, promotes the hydragogue effect and has been empirically used in the treatment of CSDH in Japan. We conducted a prospective randomized study to investigate whether Goreisan treatment decreases the recurrence rate of CSDH. Between March 2013 and December 2018, a total of 224 patients who underwent initial burr hole surgery for CSDH were randomly assigned to receive Goreisan for 3 months (Group G) or no medication (Group N). The primary endpoint was symptomatic recurrence within 3 months postoperatively, and the secondary endpoint was complications, including the adverse effects of Goreisan. Of 224 randomized patients, 208 were included in the final analysis (104 in Group G and 104 in Group N). The overall recurrence rate was 9.1% (19/208). The recurrence rate of Group G was lower than that of Group N (5.8% vs 12.5%, P = 0.09), but the difference was not statistically significant. However, a significant preventive effect of Goreisan was found in 145 patients with high-risk computed tomography (CT) features, namely, homogeneous and separated types (5.6% vs 17.6%, P = 0.04). Although the present study did not prove the beneficial effect of Goreisan treatment, it suggested the importance of selecting patients with an increased risk of recurrence. A subset of patients whose hematoma showed homogeneous and separated patterns on CT image might benefit from Goreisan treatment.

Keywords: Goreisan; chronic subdural hematoma; prospective randomized trial; recurrence.

Fig. 1

CONSORT flow diagram for patient screening and randomization.

Fig. 2

(A) Subtypes of CT scan finding used in this study according to Nakaguchi classification. (B) Bar graphs showing the recurrence rates according to CT classifications of hematoma. There was no significant difference in recurrence rate between each CT classification (P = 0.27). Note that recurrence occurs at ≥10% for homogenous- and separated-type hematomas, while the risks of recurrence are sufficiently low for laminar- and trabecular-type hematomas. (C) Bar graphs demonstrating the preventive effect of Goreisan for chronic subdural hematoma recurrence in patients with homogeneous and separated types (5.6% vs 17.6%, P = 0.04). CT: computed tomography.