Optimizing Epilepsy Surgery with Intraoperative MR Imaging

Abstract

Summary: Purpose:The surgical treatment of medically intractable temporal lobe epilepsy includes the resection of temporal lobe structures. Although the reported seizure-free outcomes are highly variable, there is growing evidence that the extent of resection of the mesiotemporal lobe directly correlates with seizure control.Methods: A moveable, high-field intraoperative magnetic resonance (MR) system was used to monitor and optimize the resection of the amygdala and hippocampus in 14 epilepsy patients. Fourteen patients with intractable seizures of temporal lobe origin underwent standard preoperative investigations including MR imaging, EEG telemetry, single-photon emission computed tomography, and neuropsychologic and sodium amytal testing. Anterior temporal lobectomy was performed on 10 patients, whereas four were treated with selective amygdalohippocampectomy. Intraoperative electrocorticography was applied as required. For all procedures, the objective was to resect the amygdala completely, and hippocampus to the posterior margin of the brainstem.Results: Interdissection intraoperative MR imaging taken when optimal resection was thought to have been achieved revealed residual unresected amygdala or hippocampus in seven of 14 patients. An unexpected acute hematoma was found in one patient. At 17 months' follow-up, 13 (93%) of 14 patients are seizure free or have significantly improved seizure control.Conclusions: The mobile high-field intraoperative MR system provides high-resolution images without restriction on surgical instruments or techniques. The ability to identify and resect residual mesial temporal lobe targets before craniotomy closure is of potentially tremendous value in optimizing seizure control.

Integration of functional neuronavigation and intraoperative MRI in surgery for drug-resistant extratemporal epilepsy close to eloquent brain areas

“…23,41 To our knowledge, only a few studies on epilepsy surgery performed with the aid of 1.5-T iMRI systems exist. 5,21,22,26,46 Neuronavigation became popular recently for lesionectomy of temporal and extratemporal regions, 6 lesions of the insular region, 49 and callosotomy. 20 With more than 15 years of experience with neuronavigation and intraoperative imaging, our department successfully developed and integrated multimodal imaging techniques in daily neurosurgery.…”

Incorporation of a laser range scanner into image‐guided liver surgery: Surface acquisition, registration, and tracking

“…There have been many groups who have implemented iMR into their image-guided surgical systems, and a sampling of the research can be found in the literature. [2][3][4][5][6][7] While iMR does provide a complete set of updated volumetric data, there are some disadvantages. Currently, it is difficult, time-consuming, and expensive to install an intraoperative magnetic resonance unit into an operating suite.…”

Combining pyramidal tract mapping, microscopic-based neuronavigation, and intraoperative magnetic resonance imaging improves outcome of epilepsy foci resection in the sensorimotor cortex

“…So far, the intraoperative MRI technique has been mostly applied in neurosurgical resection of tumors, rather than in epilepsy surgery. For the two available iMRI applications in epilepsy surgery, the epileptic foci were both located in the temporal lobe (3,12). In this paper, we applied the iMRI technique, combined with microscopic-based neuronavigation to 31 patients in Group II.…”