Postoperative course and recurrence of chronic subdural hematoma

Abstract

Objective: Chronic subdural hematoma (CSDH) is known to have a significant recurrence rate. There are different criteria defining the recurrence of CSDH. We evaluated the postoperative course of CSDH and tried to propose the reasonable criteria of recurrence.

Methods: We retrospectively examined the medical records and pre- and postoperative CT scans of 149 consecutive patients who underwent surgery from January 2005 to December 2009. Diagnosis was confirmed by CT scanning or MRI. The postoperative courses were either resolved or recurrent. The resolved CSDH was one of the three types; early resolution, delayed resolution, or late resolution. The recurrent CSDH was one of the four types; recurrence without resolution, early recurrence after resolution, late recurrence after resolution, or recurrent-and-resolved type.

Results: The CSDH was resolved within 30 days after surgery in 58 (39%) patients, between 1 to 3 months in 62 (42%), and after 3 months in 11 (7%) patients. The CSDH was recurred in 18 (12%) patients. Late resolution or recurrence was more common in the aged. The recurrent hematoma was seen on the same side in 11 patients, on the different side in 7 patients. Recurrence was significantly more common in the thick hematomas.

Conclusion: For a working criteria of the recurrence of CSDH, we propose the early recurrence as return of symptoms or reaccumulation of the hematoma after a surgery within 3 months regardless of the location, amount or repeated operations. The late recurrence can be defined as reappearance or enlargement of a liquefied hematoma within the cranial cavity surrounded by the membranes or persistent CSDH beyond 3 months after surgery.

Keywords: Chronic subdural hematoma; Craniocerebral trauma; Diagnosis; Recurrence; Risk Factors.

Figures

Fig. 1

Postoperative course of the resolved chronic subdural hematoma. Early resolution is defined as resolution of the hematoma within 30 days after surgery (1). Delayed resolution is defined as resolution of the hematoma between 1 to 3 months (2). Late resolution is defined as resolution of the hematoma after 3 months or more (3).

Fig. 2

An example of a delayed resolution. The hematoma is resolved within 3 months.

Fig. 3

An example of a late resolution. The hematoma is remained till 292 days after surgery.

Fig. 4

Postoperative courses of the recurrent chronic subdural hematoma. Recurrence without resolution is defined as increased volume of the hematoma without resolution (4). Early recurrence after resolution is defined as recurrence of the resolved hematoma within 3 months after surgery (5). Late recurrence after resolution is defined as recurrence of the resolved hematoma after 3 months or more (6). Finally, the recurrent-and-resolved type, which is the spontaneously resolved recurrent CSDH (7).

Fig. 5

The case 18 had a history of chronic subdural hematoma on the right frontal region in March 1997. She was suffered from the schizophrenia for more than 10 years. Chronic subdural hematomas were found on both sides in February 2007. She recovered form the chronic subdural hematoma by bilateral burr holes.