Intracranial hemorrhage (ICH) is the most significant complication associated with the placement of stereotactic intracerebral electrodes. Previous reports have suggested that hypertension and the use of microelectrode recording (MER) are risk factors for cerebral hemorrhage. The authors evaluated the incidence of symptomatic ICH in a large cohort of patients with various diseases treated with stereotactic electrode placement. They examined the effect of comorbidities on the risk of ICH and independently assessed the risks associated with age, sex, use of MER, diagnosis, target location, hypertension, and previous use of anticoagulant medications. The authors also evaluated the effect of hemorrhage on length of hospital stay and discharge disposition.
Between 1991 and 2005, 567 electrodes were placed by two neurosurgeons during 337 procedures in 259 patients. Deep brain stimulation (DBS) was performed in 167 procedures, radiofrequency lesioning (RFL) of subcortical structures in 74, and depth electrodes were used in 96 procedures in patients with epilepsy. Electrodes were grouped according to target, patient diagnosis, use of MER, patient history of hypertension, and patient prior use of anticoagulant medication (stopped 10 days before surgery). The Charlson Comorbidity Index (CCI) was used to evaluate the effect of comorbidities. The CCI score, patient age, length of hospital stay, and discharge status were continuous variables. Symptomatic hemorrhages were grouped as transient or leading to permanent neurological deficits.
The risk of hemorrhage leading to permanent neurological deficits in this study was 0.7%, and the risk of symptomatic hemorrhage was 1.2%. A patient history of hypertension was the most significant factor associated with hemorrhage (p = 0.007). Older age, male sex, and a diagnosis of Parkinson disease (PD) were also significantly associated with hemorrhage (p = 0.01, 0.04, 0.007, respectively). High CCI scores, specific target locations, and prior use of anticoagulant therapy were not associated with an increased risk of hemorrhage. The use of MER was not found to be correlated with an increased hemorrhage rate (p = 0.34); however, the number of hemorrhages in the patients who underwent DBS was insufficient to draw definitive conclusions. The mean length of stay for the DBS, RFL, and depth electrode patient groups was 2.9, 2.6, and 11.0 days, respectively. For patients who received DBS and RFL, the mean duration of hospitalization in cases of symptomatic hemorrhage was 8.2 days compared with 2.7 days in those without hemorrhaging (p < 0.0001). Three of the seven patients with symptomatic hemorrhages were discharged home.
The placement of stereotactic electrodes is generally safe, with a symptomatic hemorrhage rate of 1.2%, and a 0.7% rate of permanent neurological deficit. Consistent with prior reports, this study confirms that hypertension is a significant risk factor for hemorrhage. Age, male sex, and diagnosis of PD were also significant risk factors. Patients with symptomatic hemorrhage had longer hospital stays and were less likely to be discharged home.
Abbreviations used in this paper:CCI = Charlson Comorbidity Index; CT = computed tomography; DBS = deep brain stimulation; ICH = intracranial hemorrhage; MER = microelectrode recording; MR = magnetic resonance; PD = Parkinson disease; RFL = radiofrequency lesioning; STN = subthalamic nucleus.
FroehnerMKochRLitzRHellerAOehlschlaegerSWirthMP: Comparison of the American Society of Anesthesiologists Physical Status classification with the Charlson score as predictors of survival after radical prostatectomy. Urology62:698–7012003
GorgulhoADe SallesAAFrighettoLBehnkeE: Incidence of hemorrhage associated with electrophysiological studies performed using macroelectrodes and microelectrodes in functional neurosurgery. J Neurosurg105:888–8962005
PaleriVWightRG: Applicability of the adult comorbidity evaluation—27 and the Charlson indexes to assess comorbidity by notes extraction in a cohort of United Kingdom patients with head and neck cancer: a retrospective study. J Laryngol Otol116:200–2052002