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Published on: March 26, 2019
Incidence of hemorrhage associated with electrophysiological studies performed using macroelectrodes and
Alessandra Gorgulho1, Antonio A F De Salles, Leonardo Frighetto
1Division of Neurosurgery, University of California at Los Angeles, California, USA.
Object:
The goal of this study was to analyze the incidence of intracranial bleeding in patients who underwent procedures guided by microelectrode recording (MER) rather than by macroelectrode stimulation alone.
Methods:
Between March 1994 and July 2001, 178 patients underwent 248 functional neurosurgical procedures performed by the same team at the University of California at Los Angeles. The procedures included pallidotomy (122 patients), thalamotomy (19 patients), and implantation of deep brain stimulation electrodes in the subthalamic nucleus (36 patients), globus pallidus internus (17 patients), and ventralis intermedius nucleus (54 patients). One hundred forty-four procedures involved macroelectrode stimulation and 104 involved MER. Groups were analyzed according to the presence of arterial hypertension, MER or macroelectrode stimulation use, and occurrence of hemorrhage. Nineteen patients with arterial hypertension underwent 28 surgical procedures. Five cases of hemorrhage (2.02%) occurred. One patient presented with hemiparesis and dysphasia but no surgery was required. The incidence of hemorrhage in patients in whom MER was performed was 2.9%, whereas the incidence in patients in whom MER was not used was 1.4% (p = 0.6529). Bleeding occurred in 10.71% of patients with hypertension and 0.91% of those who were nonhypertensive (p = 0.0111). Among the 104 patients in whom MER was performed, 12 had hypertension. Bleeding occurred in two (16.67%) of these 12 patients. An increased incidence of bleeding in hypertensive patients who underwent MER (p = 0.034) was noticed when compared with nonhypertensive patients who underwent MER. A higher number of electrode passes through the parenchyma was observed when MER was used (p = 0.0001). A positive trend between the occurrence of hemorrhage and multiple passes was noticed. Conclusions. Based on the data the authors suggest that a higher incidence of hemorrhage occurs in hypertensive patients, and a higher incidence as well in hypertensive patients who underwent MER rather than macroeletrode stimulation. Special attention should be given to MER use in hypertensive patients and particular attention should be made to multiple passes.
Insights
Microelectrode recording (MER) in functional neurosurgery may increase intracranial bleeding risk, especially in hypertensive patients. Careful consideration of MER use and electrode passes is crucial for patient safety.
Area of Science:
- Neurosurgery
- Neurology
- Medical Devices
Background:
- Functional neurosurgical procedures aim to treat movement disorders and other neurological conditions.
- Microelectrode recording (MER) and macroelectrode stimulation are techniques used to guide these procedures.
- Intracranial hemorrhage is a potential complication of neurosurgical interventions.
Purpose of the Study:
- To analyze the incidence of intracranial bleeding in patients undergoing functional neurosurgical procedures.
- To compare the risk of hemorrhage between microelectrode recording (MER) and macroelectrode stimulation alone.
- To investigate the influence of arterial hypertension on hemorrhage risk during these procedures.
Main Methods:
- A retrospective analysis of 248 functional neurosurgical procedures (pallidotomy, thalamotomy, deep brain stimulation) performed between 1994 and 2001.
- Procedures were categorized by the guidance technique used: MER or macroelectrode stimulation.
- Patient data, including arterial hypertension status and occurrence of hemorrhage, were analyzed.
Main Results:
- The overall incidence of hemorrhage was 2.02%.
- Hemorrhage occurred in 2.9% of procedures using MER versus 1.4% without MER (p=0.6529).
- Hypertensive patients had a significantly higher incidence of bleeding (10.71%) compared to non-hypertensive patients (0.91%, p=0.0111).
- Hypertensive patients undergoing MER showed an increased bleeding incidence (16.67%) compared to non-hypertensive patients undergoing MER (p=0.034).
- A higher number of electrode passes was associated with MER use (p=0.0001) and a trend towards increased hemorrhage.
Conclusions:
- Hypertension is a significant risk factor for intracranial hemorrhage during functional neurosurgery.
- Microelectrode recording (MER) may be associated with a higher bleeding risk, particularly in hypertensive patients.
- Minimizing electrode passes during MER procedures is recommended to reduce hemorrhage risk.
