Low Incidence of Subdural Grid-Related Complications in Prolonged Pediatric EEG Monitoring

Abstract

Invasive EEG monitoring is one of the best tools available for localization of epileptogenic foci in the brain. However, published data in mixed series of adult and pediatric patients show high incidence of epidural bacterial contamination, cerebrospinal fluid leakage, and skin infection after subdural electrode implantation. We sought to determine whether the complication rate from prolonged subdural electrode implantation would be lower in a purely pediatric series. Thirty-three subdural electrode implantation procedures were performed in 29 pediatric patients (age range 4–19) for an average of 7.2 days (range 3–14 days). Electrode number varied from 32 to >128 with a range of 4–11 electrode wires piercing the skin >1 cm from the primary incision. Of the 33 implantations and resections (66 craniotomies), 5 were for reimplantation. There were no permanent complications related to grid implantation. Transient complications included 1 case of prolonged prothrombin time and 1 patient with unexplained fever, both of which resolved upon removal of the grids. There were two culture-positive infections, one epidural and one superficial, both in patients undergoing reimplantation. There was no percutaneous cerebrospinal fluid leakage noted and no operation was aborted due to bleeding caused by grid placement. Our data suggest that subdural grid implantation in children is remarkably safe even for prolonged implantation, though infectious risk is significantly higher in reoperation (p = 0.019). This observation may contribute to lowering the threshold for two-stage invasive monitoring approaches in children with epilepsy.

Is Postoperative CT Scanning Predictive of Subdural Electrode Placement Complications in Pediatric Epileptic Patients?

“…Our findings are in agreement with other studies conducted on pediatric patients demonstrating that the placement of subdural grids and strips performed via craniotomy is generally a safe procedure in children with intractable epilepsy who require invasive seizure monitoring [10,11,12,13]. One explanation advocated for the relative safety of subdural electrode implants in pediatric patients is the greater plasticity of pediatric brain parenchyma and vascular structures compared to adults [13].…”

“…The need to submit a pediatric patient with intractable epilepsy to an invasive monitoring procedure by the use of subdural electrodes requires a careful balance of the risks and benefits [5,6,7,8,9,10,11,12,13,14]. …”

“…Although scalp EEG, along with other neuroimaging techniques, helps to effectively identify the general area of a seizure focus [2,3], invasive techniques have proven to be a far superior method for accurate localization [4]. Unfortunately, several reports described complications related to the placement of subdural electrodes both in the adult and in the pediatric population [5,6,7,8,9,10,11,12,13,14]. Frequently, reported complications include infection of the wound and bone flap (2–15%), CSF leaks through the skin insertion sites of the electrode cables (30%) and formation of acute symptomatic epidural (1.8–2.5%) and, particularly, subdural hematomas (2–14%) along with symptomatic brain swelling (8%) [5,6,7,8,9,10,11,12,13,14].…”

“…Unfortunately, several reports described complications related to the placement of subdural electrodes both in the adult and in the pediatric population [5,6,7,8,9,10,11,12,13,14]. Frequently, reported complications include infection of the wound and bone flap (2–15%), CSF leaks through the skin insertion sites of the electrode cables (30%) and formation of acute symptomatic epidural (1.8–2.5%) and, particularly, subdural hematomas (2–14%) along with symptomatic brain swelling (8%) [5,6,7,8,9,10,11,12,13,14]. While the implantation of subdural electrodes is generally a safe procedure in children with a low rate of clinically relevant hemorrhagic complications [10,11,12,13], the development of acute hemorrhagic complications and brain swelling can be life-threatening conditions that present mostly in the immediate postoperative period.…”

Magnetoencephalography for Pediatric Epilepsy: How We Do It

“…Eliminating the need for 2 surgical procedures reduces the length of hospitalization and the risk of complications associated with the administration of GA as well as those associated with subdural grid placement, including infection (either primary or reactivation), ischemia, CSF leak, and hemorrhage, occasionally requiring transfusion. [48][49][50] Additional potential benefits include decreased surgical and inpatient hospitalization costs, fewer lost work days for caregivers, and improving the overall experience for the family.…”