O148-396X/89/2506-099 1$02.00/0, NEUROSURGERY Vol. 25. No. 6. 1989 Printed in U.S.A. Copyright © 1989 by the Congress of Neurological Surgeons Technical notes Implantation of a Reservoir for Recurrent Subdural Hematoma Drainage Rudolf Laumer, M.D., Johannes Schramm, M.D., and Karin Leykauf Department of Neurosurgery, University of Erlangen-Niwnberg, Federal Republic of Germany In a prospective study 144 adult patients with chronic subdural hematomas were randomly divided into three treatment groups after burr-hole evacuation. The two commonly used procedures (external closed system drainage and aspiration and irrigation without any drainage) were compared to a modified technique: permanent subdural drain with subcutaneous reservoir. After the hematoma was washed out with saline solution, a silicon catheter with multiple perforations was introduced into the subdural cavity and connected to a Rickham reservoir, fixed in the frontoparietal burr hole. In patients who showed secondary deterioration or enlargement of the residual hematoma as proven by computed tomographic scan, the reservoir was punctured and the subdural fluid aspirated. The great advantage of this method is that it is practicable at the bedside as well as in the outpatient department, thus making it possible to reduce the number of additional operations. The incidence of symptomatic residual or recurrent hematoma was similar in all three groups. The reoperation rate was 4-fold greater in the groups treated with conventional therapy, when compared to the group with the implanted system. At the same time there was no indication that the implantation of the drain was less safe, as judged by the incidence of seizures and infections. (Neurosurgery 25:991-996, 1989 Key words: Chronic subdural hematoma, Operative technique, Subdural drainage The management of chronic subdural hematoma (CSH) ranges from conservative methods to craniotomy and mem- branectomy (3, 12. 14, 18, 19). In the last 10 years, the method of simple burr-hole evacuation and irrigation of the subdural cavity with saline or Ringer’s solution has become generally accepted (8. 11). This technique, however, is asso- ciated with a considerable rate of recurrent hematoma. In the literature (Table |) the rate of reoperations varies surprisingly widely between 2.7 and 30% (4. 6. 7, 10. 13, 15. 17, 20). Recent publications advocating the use of a subdural-peri- toneal shunt demonstrate that the problem of management of the CSH is not yet solved (1, 16). In a retrospective study of 155 patients with CSH. treated in our department between January |, 1982, and August 31, 1984, a reoperation rate of 19.4% was documented (9). In all patients the hematoma was evacuated via a frontoparietal burr hole. After irrigation of the subdural cavity, an external closed system drainage device was implanted for 3 days. In order to reduce this relatively high reoperation rate. an alter- native procedure using an implantable device for percuta- neous aspiration was established 3 years ago and compared to the two commonly used methods in a prospective and randomized trial. MATERIALS AND METHODS The prospective study conducted between September 1. 1984. and February 28. 1987. included a total of 144 patients. who were treated surgically for CSH. At the beginning of the study, the sequence of the three possible operative procedures for all patients included in the study was randomly assigned. In order to evaluate the efficacy of the new technique, three treatment groups were defined: permanent subdural drain with subcutaneous reservoir (Group A). external closed s tem drainage device (Group B), and burr-hole evacuation without additional drainage (Group C). In all patients in Group A, a slightly enlarged frontoparietal burr hole made. After the hematoma was washed out with saline solution, a right-angled silicon catheter (Fig. 1) with multiple perforations was introduced into the subdural cavity and connected to a subcutaneously placed Rickham reservoir, sutured to the rim of the burr hole. If necessary, this reservoir could be punctured percutaneously and the recollected subdural fluid aspirated. The steel bottom of the capsule prevented perforation and possible brain damage. In this way repeated operations could be avoided. The catheter was usually placed with its tip in an occipital direction (Fig. 2). Thus, aspiration of a persistent parietooc- cipital hematoma was possible, even if the brain expande: directly below the reservoir (Fig.3). Additional irrigations and repeated aspirations could also be performed via this device. Patients showing a normal postoperative course were dis- charged between the 4th and 8th day after surgery with a fixed appointment for our outpatient department exactly 3 weeks after the operation for neurological examination and a contro computed tomographic (CT) scan. Thus. in this study al patients were seen again 3 weeks after surgery. all had a CT scan. and all were examined by the same doctors who had treated the initial condition. Patients were instructed about the possibility of neurological deterioration and encouraged 992 LAUMER etal. Neurosurgery, Vol. 25, No. 6 TABLE | Rate of Reoperations afier Burr Hole Evacuation Number of Operative Reoperation ACUTE Patients Technique“ Rate (%) Svien and Gelety, 1964 (19) 50 2-3 BH/D 20.0 Cameron, 1978 (4) 112 2 BH/L 2.7 Markwalder et al., 1981 (12) 32 2 BH/D 3.1 Harders et al., 1982 (7) 100 1 BH/D 24.0 Oku et al.. 1984 (15) 83 1 BH 3.6 Eggert et al., 1984 (6) 100 | BH/D 23.0 Robinson, 1984 (17) 123 2-4 BH/D,L.V 12,3 BH 30.0 Lausberg and Boger, 1987 (10) “BH, burr hole: D, drainage; L, lumbar injection; V, ventricular injection. Fic. 1. Implantable device for percutaneous puncture, aspiration, and irrigation of the subdural cavity. Fic. 2. The implanted device in situ, demonstrating the position of the implanted subdural drain. to come to the hospital immediately in case of such a deteri- oration. The indications for reoperation were as follows: 1) if an initial neurological deficit increased, recurred. or did not improve and the CT scan showed a corresponding space- occupying lesion; 2) if there was an increase in the size of the hematoma with or without neurological deterioration: and 3) if there was permanent or recurrent severe headache with corresponding findings on the CT scan. Ou,