T here are now several studies and recent meta-analyses showing that stereo-electroencephalography (sEEG) procedures are significantly safer than subdural electrode implantations for the intracranial evaluation of epilepsy. 1–8 Furthermore, sEEG implantation can effectively localize epileptic foci by comprehensively sampling the epileptogenic network, by accessing deeper cortical areas and multiple noncontiguous lobes, and by facilitating bilateral exploration. 2 , 4 , 9–11 Traditional sEEG, as devised by Jean Talairach, 12 entails the use of orthogonal
Patrick S. Rollo, Matthew J. Rollo, Ping Zhu, Oscar Woolnough, and Nitin Tandon
Kathrin Machetanz, Florian Grimm, Thomas V. Wuttke, Josua Kegele, Holger Lerche, Marcos Tatagiba, Sabine Rona, Alireza Gharabaghi, Jürgen Honegger, and Georgios Naros
T he use of stereo-electroencephalography (SEEG) within the insula to determine seizure onset prior to resective surgery is well established for patients with medically intractable epilepsy. 1–3 However, implantation of SEEG electrodes in the insula is still challenging due to its anatomical features. First, the insular cortex is located deep inside the sylvian fissure, enclosed and covered by the frontoparietal and temporal opercula. Second, the cytoarchitectonic and functional structure of the insula is complex and poorly understood. 4 , 5 Despite its
Jun T. Park, Guadalupe Fernandez Baca Vaca, Rachel Tangen, and Jonathan Miller
Resection of the hippocampus ipsilateral to the verbal memory–dominant hemisphere frequently results in severe memory deficits. In adults with epilepsy, multiple hippocampal transections (MHTs) have resulted in excellent seizure outcome with preservation of verbal memory. The authors report the first detailed case of a child undergoing MHTs for mesial temporal lobe epilepsy. A 13-year-old right-handed boy had intractable seizures characterized by epigastric discomfort evolving to unresponsiveness and chewing automatisms, lasting 1 minute and occurring 2–3 times weekly, sometimes ending in a generalized tonic-clonic seizure. He had no seizure risk factors and nonfocal examination results. Interictal electroencephalography (EEG) showed frequent left temporal epileptiform discharges (maximum FT9) and intermittent slowing. Video EEG, FDG-PET, and 1.5-T MRI were nonlocalizing. Neuropsychological evaluation suggested left temporal lobe dysfunction. A stereo-EEG investigation using 8 electrodes localized the seizure onset zone to the anterior mesial temporal region, immediately involving the hippocampus. The temporal pole and amygdala were resected en bloc with 3 MHTs. Comparison of neuropsychological tests 4 months before and 6 months after the surgery showed a significant decline only in confrontational naming and no significant change in verbal memory. Six and a half years later, the patient remains seizure free with no antiepileptic drugs. In children with established hemispheric dominance suffering from mesial temporal lobe epilepsy, MHTs may be an option.
Christian Dorfer, Georgi Minchev, Thomas Czech, Harald Stefanits, Martha Feucht, Ekaterina Pataraia, Christoph Baumgartner, Gernot Kronreif, and Stefan Wolfsberger
The authors' group recently published a novel technique for a navigation-guided frameless stereotactic approach for the placement of depth electrodes in epilepsy patients. To improve the accuracy of the trajectory and enhance the procedural workflow, the authors implemented the iSys1 miniature robotic device in the present study into this routine.
As a first step, a preclinical phantom study was performed using a human skull model, and the accuracy and timing between 5 electrodes implanted with the manual technique and 5 with the aid of the robot were compared. After this phantom study showed an increased accuracy with robot-assisted electrode placement and confirmed the robot's ability to maintain stability despite the rotational forces and the leverage effect from drilling and screwing, patients were enrolled and analyzed for robot-assisted depth electrode placement at the authors' institution from January 2014 to December 2015. All procedures were performed with the S7 Surgical Navigation System with Synergy Cranial software and the iSys1 miniature robotic device.
Ninety-three electrodes were implanted in 16 patients (median age 33 years, range 3–55 years; 9 females, 7 males). The authors saw a significant increase in accuracy compared with their manual technique, with a median deviation from the planned entry and target points of 1.3 mm (range 0.1–3.4 mm) and 1.5 mm (range 0.3–6.7 mm), respectively. For the last 5 patients (31 electrodes) of this series the authors modified their technique in placing a guide for implantation of depth electrodes (GIDE) on the bone and saw a significant further increase in the accuracy at the entry point to 1.18 ± 0.5 mm (mean ± SD) compared with 1.54 ± 0.8 mm for the first 11 patients (p = 0.021). The median length of the trajectories was 45.4 mm (range 19–102.6 mm). The mean duration of depth electrode placement from the start of trajectory alignment to fixation of the electrode was 15.7 minutes (range 8.5–26.6 minutes), which was significantly faster than with the manual technique. In 12 patients, depth electrode placement was combined with subdural electrode placement. The procedure was well tolerated in all patients. The authors did not encounter any case of hemorrhage or neurological deficit related to the electrode placement. In 1 patient with a psoriasis vulgaris, a superficial wound infection was encountered. Adequate physiological recordings were obtained from all electrodes. No additional electrodes had to be implanted because of misplacement.
The iSys1 robotic device is a versatile and easy to use tool for frameless implantation of depth electrodes for the treatment of epilepsy. It increased the accuracy of the authors' manual technique by 60% at the entry point and over 30% at the target. It further enhanced and expedited the authors' procedural workflow.
Salma M. Bakr, Ajay Patel, Mohamed A. Zaazoue, Kathryn Wagner, Sandi K. Lam, Daniel J. Curry, and Jeffrey S. Raskin
localization, 3 , 6–9 Jean Talairach and Jean Bancaud first developed stereo-electroencephalography (sEEG). 10–13 Subsequent advances in stereotactic frames allowed surgeons to manually fuse atlas-based images with patient-specific air ventriculography and conventional angiography to place orthogonal depth electrodes (DEs) along an adaptive grid system. 10 An estimated 30% of children and 20% of adults with nonlesional MRI findings also have no clear suspected SOZ based on phase I data, and many will subsequently have to undergo iEEG. 5 , 14 Such nonlesional cases
JNSPG 75th Anniversary Invited Review Article
Jarod L. Roland and Matthew D. Smyth
Stereo-Electroencephalography Stereotactic placement of multiple intraparenchymal depth electrodes for extraoperative intracranial electrophysiology monitoring can be performed with relatively low risks and high yield through the stereo-electroencephalography (SEEG) technique. At many centers, SEEG is rapidly expanding in practice, often replacing surface-based electrocorticography (ECoG) for many indications. Because SEEG utilizes a percutaneous implantation technique, the pain and recovery associated with traditional craniotomy is greatly reduced, but the risks of
Maya Harary and G. Rees Cosgrove
, stereo-electroencephalography (SEEG), and endonasal procedures. 19 , 32 , 33 , 35 , 37 , 39 , 41 FIG. 2. Talairach stereotaxic apparatus. 1 = frame; 2 = luminous sight target for x-ray beam centering; 3 = level; 4 = cranial fixation fastener; 5 = double grid. Reproduced from Talairach J: Souvenirs des Études Stéréotaxiques du Cerveau Humain . John Libbey Eurotext, 2007. Published with permission. Talairach and colleagues used their stereotactic apparatus to study 100 cadaveric brains, which in 1957 resulted in the first stereotaxic atlas of the human deep gray nuclei
Alessandro De Benedictis, Andrea Trezza, Andrea Carai, Elisabetta Genovese, Emidio Procaccini, Raffaella Messina, Franco Randi, Silvia Cossu, Giacomo Esposito, Paolo Palma, Paolina Amante, Michele Rizzi, and Carlo Efisio Marras
, 36 neuroendoscopy, 8 , 69 , 71 radiosurgery, 2 neuromodulation treatments, 43 , 45 and other stereotactic procedures. 7 , 37 Recently, more sophisticated systems have been proposed for other complex treatments, such as brain tumor removal, 4 , 35 , 40 , 42 , 61 , 62 deep electrode placement for stereo-electroencephalography (SEEG) recording, 14 , 15 , 16 , 29 laser ablation in medically intractable epilepsy, 13 , 30 , 50 and other functional approaches. 66 In this context, robotic technology is continuously improving, mainly in terms of versatility
Marc Zanello, Johan Pallud, Nicolas Baup, Sophie Peeters, Baris Turak, Marie Odile Krebs, Catherine Oppenheim, Raphael Gaillard, and Bertrand Devaux
from 1946 to 1952 by David. Talairach focused on epilepsy surgery and developed stereo-electroencephalography. 12 Talairach kept in touch with his psychiatry colleagues from his initial career. As mentioned earlier, he joined David on a tour to different provincial hospitals and continued after David’s departure, ending at the Sarthe Psychiatric Hospital. 23 Talairach eventually also visited the Lille region’s Public Institution of Mental Health (Lommelet, France) to perform psychosurgery procedures. 1 The tight regulation on psychosurgery resulted in scant
Baotian Zhao, Chao Zhang, Xiu Wang, Yao Wang, Jiajie Mo, Zhong Zheng, Lin Ai, Kai Zhang, Jianguo Zhang, Xiao-qiu Shao, and Wenhan Hu
: evidence from in vivo probabilistic tractography . Neuroimage . 2012 ; 59 ( 4 ): 3514 – 3521 . 35 Uddin LQ , Nomi JS , Hébert-Seropian B , Structure and function of the human insula . J Clin Neurophysiol . 2017 ; 34 ( 4 ): 300 – 306 . 36 Rheims S , Demarquay G , Guénot M , Ipsilateral head deviation related to orbito-frontal and fronto-polar seizures . Epileptic Disord . 2005 ; 7 ( 2 ): 97 – 102 . 37 David O , Blauwblomme T , Job AS , Imaging the seizure onset zone with stereo-electroencephalography . Brain . 2011 ; 134 ( Pt 10