Lumbar cerebral spinal fluid drainage during long-term electrocorticographic monitoring with subdural strip electrodes: elimination of cerebral spinal fluid leak

Cranioplasty with Titanium Might Be Suitable for Adult Epilepsy Surgery After Subdural Placement Surgery To Avoid Surgical Site Infection

BACKGROUND

The purpose of the present study was to compare the surgical site infection (SSI) rates between resorbable plates and titanium plates used for adult patients with intractable epilepsy who had undergone epilepsy surgery after subdural electrode placement.

METHODS

We performed subdural electrode surgery, followed by epilepsy surgery, for 87 adult patients with intractable epilepsy. The epilepsy surgery included 75 focus resections and 12 corpus callosotomies. We compared the SSI rates between patients who had undergone cranioplasty with titanium and resorbable plates after epilepsy surgery.

RESULTS

Of the 87 patients, 43 had undergone cranioplasty with resorbable plates (group A) and 44 had undergone cranioplasty with titanium plates (group B). The frequency of SSI was significantly greater in group A (7 patients; 16.3%) than in group B (1 patient; 2.3%; P = 0.03, Fisher's exact test). Univariate regression analysis also showed a significantly greater infection rate with the resorbable plates (P = 0.024).

CONCLUSION

For epilepsy surgery of adult patients after subdural electrode placement surgery, the SSI rate for cranioplasty was greater with resorbable plates than with titanium plates.

Placement of subdural grids in pediatric patients: technique and results

PURPOSE

The purpose of this study is to describe common indications and technique for the application of chronic invasive electrodes in the pediatric patient suffering from medically intractable epilepsy.

METHODS

This chapter was prepared based on a retrospective review of the literature and personal experience based from a large tertiary epilepsy center.

CONCLUSIONS

Invasive subdural recordings are a safe and efficacious tool to identify the epileptogenic zone and its relationship to functional cortex in highly selected patients with medically refractory epilepsy. The ability to localize the EZ approaches 90 to 100 %, but seizure-free outcome is more complex depending greatly on the experience of the surgical team and the extent of resection.

Subdural Electrode-Associated Complications: A 20-Year Experience

BACKGROUND

Implantation of subdural strip and grid electrodes is a common methodology in the invasive evaluation of patients with medically refractory epilepsy. Although their implantation is safe, the occurrence of implantation-associated complications can occasionally be troublesome.

METHODS

In our current retrospective study, 185 patients undergoing subdural grid/strip implantation for invasive monitoring were examined. Their ages ranged between 16 and 48 years (mean 23.6). AdTech (Racine, Wisc., USA) strip and grid electrodes were implanted under general endotracheal anesthesia in all our cases. Duration of electroencephalographic monitoring ranged from 2 to 25 days (mean 10.8). The follow-up period ranged from 24 to 60 months (mean 44.6 months).

RESULTS

The most common complication in our series was the development of postoperative epidural hematoma in 3 patients (1.6%), while 2 patients (1.1%) suffered a subdural hematoma. Two patients (1.1%) developed significant brain edema postoperatively, 2 others (1.1%) developed an infection, while 2 patients (1.1%) experienced transient aphasia. Two patients (1.1%) had fatal outcomes in our series. Interestingly, in 5 patients (2.7%) nonhabitual seizures were recorded.

CONCLUSION

Thorough understanding, early identification and prompt management of potential complications can minimize the risks associated with the implantation of subdural electrodes.

Long-term surface cortical cerebral blood flow monitoring in temporal lobe epilepsy

Long-term subdural surface cortical cerebral blood flow (CBF) and electrocorticographic monitoring was performed in 12 patients with complex partial seizures. A total of 40 seizures were analyzed. Baseline CBF values from nonepileptic and epileptic temporal lobe (mean +/- standard error) were 60.0 +/- 1.0 and 50.2 +/- 1.8 ml/100 g per minute, respectively (P < 0.05). In general, clinical seizure onset was preceded by a 20-minute preictal CBF increase from baseline in the epileptic temporal lobe. Peak early postictal CBF values of nonepileptic and epileptic temporal lobes were 57.7 +/- 13.3 and 89.0 +/- 21.7 ml/100 g per minute (P > 0.05) at 5.2 +/- 2.2 and 2.4 +/- 1.0 minutes (P > 0.05) after clinical seizure onset, respectively. Statistically significant differences between nonepileptic and epileptic temporal lobe CBF were detected at 50 minutes (74.0 +/- 14.2 and 37.5 +/- 9.2 ml/100 g per minute, respectively; P < 0.05) and 60 minutes (75.6 +/- 13.6 and 36.1 +/- 8.5 ml/100 g per minute, respectively; P < 0.05) postictal. The data suggest that the optimal times for CBF analysis to differentiate epileptic from nonepileptic temporal lobe are 1) during the interictal period and 2) late (50 to 60 minutes) postictal. The results of this study should improve the understanding of the dynamic cerebral perfusion patterns in the epileptic human brain.