Robles Santiago Gil, Gelisse Philippe, El Fertit Hassan, Tancu Cornel, Duffau Hugues, Crespel Arielle, Coubes Philippe
Epilepsy Unit, Department of Neurosurgery, IGF-UMR CNRS 5203, INSERM U661, Montpellier, France.
Stereotact Funct Neurosurg. 2009;87(6):368-78. doi: 10.1159/000249818. Epub 2009 Oct 21.
Direct invasive EEG recordings of the insula - due to its particular anatomical position, deeply seated between both opercula - can only be performed with intracerebral electrodes. To date, the technique most commonly used for insular stereoelectroencephalography (SEEG) is the orthogonal-transopercular electrode approach with the Talairach methodology. We propose another technique utilizing MRI with transinsular parasagittal electrodes and a posterior entry point. This avoids passing through the opercula and sylvian vessels running over the insular surface.
Nine patients, whose seizures implicated the insula, underwent brain surgery. Under general anesthesia with a Leksell frame, 3D-T(1) SPGR MRI with gadolinium enhancement was achieved. Surgical planning was performed using the StealthStation with an entry point in the parieto-occipital junction setting the target for the first contact of the lead at the most anterior part of the insula. The trajectory was manipulated in order to have at least 4 contacts per electrode track within the insular cortex. All patients had a postoperative MRI to verify the exact position of each contact.
Insular seizures were recorded in all patients. There was neither intracranial bleeding nor infection. In all of the cases, except 1, the seizures recorded were found to be propagations of the primary epileptic zone located in the temporal lobe, either in the mesial structures or the superior temporal gyrus. Eight patients were operated, 7 with an antero-mesial temporal lobectomy and 1 with dysplasia of the superior temporal gyrus. No insular resections were performed.
We report a novel technique for insular SEEG with parasagittal electrodes, parallel to the insular cortex, with an entry point at the parieto-occipital junction. This technique is based entirely on use of MRI, and avoids passing through the opercula and sylvian vessels.
由于岛叶特殊的解剖位置，深埋于双侧脑盖之间，因此对岛叶进行直接侵入性脑电图记录只能通过脑内电极来完成。迄今为止，岛叶立体脑电图（SEEG）最常用的技术是采用Talairach方法的经脑盖正交电极法。我们提出了另一种利用MRI的技术，即经岛叶矢状旁电极法，并采用后入路。这样可避免经过脑盖和走行于岛叶表面的大脑中血管。
9例癫痫发作累及岛叶的患者接受了脑部手术。在使用Leksell框架的全身麻醉下，完成了钆增强的三维T1加权扰相梯度回波（SPGR）MRI检查。使用StealthStation进行手术规划，入路点位于顶枕交界处，将电极的首次接触靶点设定在岛叶最前部。调整电极轨迹，以便在岛叶皮质内每个电极轨道至少有4个接触点。所有患者术后均进行MRI检查，以确认每个接触点的确切位置。
所有患者均记录到岛叶癫痫发作。既无颅内出血，也无感染。在所有病例中，除1例之外，记录到的癫痫发作均为起源于颞叶的原发性癫痫灶的扩散，累及内侧结构或颞上回。8例患者接受了手术，7例行前内侧颞叶切除术，1例行颞上回发育异常切除术。未进行岛叶切除术。
我们报告了一种用于岛叶SEEG的新技术，采用矢状旁电极，与岛叶皮质平行，入路点位于顶枕交界处。该技术完全基于MRI的应用，避免了经过脑盖和大脑中血管。
