Stereotactically-guided craniotomy for cavernous angiomas presenting wit epilepsy

Application of neuronavigator coupled with an operative microscope and electrocorticography in epilepsy surgery

Application of neuronavigator coupled with an operative microscope and electrocorticography (ECoG) is a new trial for epilepsy surgery for achieving better seizure outcome and better efficiency for lesionectomy. We used a neuronavigator coupled with a microscope to delineate the magnetic resonance image-detected lesion for lesionectomy and used ECoG for evaluation of the epileptogenic foci. There were 46 patients with medically intractable partial seizures who underwent craniotomy for epilepsy surgery. Half of the patients had lesions at the temporal lobe and another half at the extratemporal lobe. Sixty-one percent of the patients were seizure-free (grade I) and 22% were nearly seizure-free (grade II). Overall, 83% of the patients had satisfactory seizure control. Complete lesion removal was successful in 37 patients (80%). For lesions with requiring complete removal, neuronavigator coupled with a microscope was 95% effective for lesionectomy. Class A of postresection ECoG had a higher rate of seizure-free outcome (92%) (P < .05). On the other hand, 93% of patients (26/28) with seizure-free outcome (grade I) needed complete lesion resection (P < .05). Lesions at the extratemporal lobe yielded a higher rate of seizure-free outcome (78.2%, 18/23) (P < .05). Application of neuronavigator and ECoG (additional cortical resection) is usually necessary for temporal lobe lesions. All patients with cavernous hemangioma were seizure-free. The complication rate in our study was 8.7%. Neuronavigator coupled with a microscope provides efficacy and safety to complete lesionectomy, which is a key point of seizure outcome. Intraoperative ECoG is valuable for evaluating the epileptogenic foci for epilepsy surgery especially for lesions at the temporal lobe.

Cavernous haemangiomas, epilepsy and treatment strategies

BACKGROUND

Cavernous haemangiomas (cavernomas) are benign vascular malformations which can be found at any region within the central nervous system. Epilepsy is the most frequent manifestation of this malformation. Magnetic resonance imaging (MRI) used for the diagnostic evaluation of symptomatic seizures is a sensitive and specific method for the detection of cavernomas. Due to an increased application of MR imaging in the diagnostic evaluation of symptomatic seizures cavernomas have been found with increasing frequency over the past years. To achieve optimal treatment of patients with cavernous haemangiomas and epilepsy both medical and surgical treatment have to be considered.

OBJECTIVE

This paper reviews published studies and presents our own results concerning current treatment schedules of epileptogenic cavernomas.

RESULTS

In patients with intractable epilpesies surgical treatment of cavernomas seems to be the most successful antiepileptic therapy. Whether microsurgical lesionectomy, including the removal of only the cavernoma, or a more extensive resection is needed to achieve this aim are discussed.

CONCLUSION

New data acquired with high-resolution imaging (MRI, PET) and electrophysiology indicate that magnetencephalography (MEG) may contribute to the delineation of epileptogenic tissue bordering the lesion, thus permitting appropriate inclusion of this specific area within the resection, instead of performing a simple lesionectomy.

Resection of a dominant-hemisphere intraventricular meningioma facilitated by functional magnetic resonance imaging. Case report

Intraventricular meningiomas of the lateral ventricle occur relatively rarely, but they are often large at the time of detection and present more commonly on the left side. Although the ability to resect these tumors safely has greatly improved over time, standard surgical approaches often traverse cortex close to areas of specific cortical function. Precise cortical mapping of language and sensorimotor cortices can be accomplished noninvasively by using functional magnetic resonance (fMR) imaging. The authors used fMR imaging in planning the cortical incision for resection of a large intraventricular trigone meningioma in the dominant hemisphere of a patient who, postoperatively, suffered no aphasia or hemiparesis. The authors discuss the advantages of mapping cortical function preoperatively with fMR imaging when approaching intraventricular lesions.