title: Contralateral subdural effusion after decompressive craniectomy in patients with severe traumatic brain injury: clinical features and outcome.
abstract: BACKGROUND
  Contralateral subdural effusion (SDE) is usually considered as an uncommon complication after decompressive craniectomy (DC) for head trauma. This complication may need more aggressive treatment because of its tendency to cause midline shift and neurologic deterioration. In this article, we present our experience with this group of patients and discuss the diagnosis and management of this entity.
  
  
  METHODS
  This study included 13 patients with severe traumatic brain injury who developed contralateral SDE after DC. Clinical and radiographic information was obtained through a retrospective review of the medical records and the radiographs.
  
  
  RESULTS
  The average time from the procedure of DC to the diagnosis of contralateral SDE was 13 days. Deterioration of clinical condition or appearance of new symptoms/signs related to the contralateral SDE was noted in four patients. In the remaining nine patients without apparent clinical deterioration, the contralateral SDE was discovered on routine computed tomography scan. Six patients were treated conservatively and the contralateral SDE resolved gradually. In six patients who underwent burr hole craniectomy to evacuate the SDE, the operation had successfully drained the SDE in four patients. Two patients received subsequent subduroperitoneal shunt to manage the reaccumulation of SDE. In one patient, subduroperitoneal shunt and cranioplasty were performed simultaneously to treat the SDE. Subsequently, six patients (46.2%) developed hydrocephalus and underwent ventriculoperitoneal shunt operation.
  
  
  CONCLUSIONS
  Contralateral SDE may not be a rare complication after DC. Its diagnosis may be delayed or missed when it is asymptomatic or the clinical condition of the patient masks its clinical manifestations. It may be reasonable to repeat a computed tomography scan to detect contralateral SDE 2 weeks to 3 weeks after DC, irrespective of the clinical condition. In addition, posttraumatic hydrocephalus is a common late consequence in these patients. Close surveillance in these patients is indicated to prompt appropriate management.
authors: Department of Neurosurgery, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Hsien, Taiwan.
authors: Tsung-Ming
authors: TM
authors: Su
authors: Tsung-Han
authors: TH
authors: Lee
authors: Yu-Hua
authors: YH
authors: Huang
authors: Feng-Wen
authors: FW
authors: Su
authors: Wu-Fu
authors: WF
authors: Chen