Deep brain stimulation of thalamic nuclei for the treatment of drug-resistant epilepsy: Are we confident with the precise surgical target?. (February 2023)

• Record Type: Journal Article
• Authors: Remore, Luigi G.; Omidbeigi, Mahmoud; Tsolaki, Evangelia; Bari, Ausaf A.
• Is Part Of: Seizure. Volume 105(2023)
• Page Start: 22
• Page End: 28
• Publication Date: 2023-02
• Subjects: Deep brain stimulation -- Thalamus -- Epilepsy -- Functional neurosurgery -- Targeting; ANT anterior nucleus of the thalamus -- CM centromedian nucleus -- DBS deep brain stimulation -- DRE drug-resistant epilepsy -- EDGE-MICRA 3D edge-enhancing gradient eco with multi-imaging co-registration and averaging -- FGATIR fast gray matter acquisition T1 inversion recovery -- LGS Lennox-Gastault syndrome -- MMT mammillothalamic tract -- MP2RAGE magnetization prepared 2 rapid gradient echo -- MRI magnetic resonance imaging -- QSM quantitative susceptibility mapping; Epilepsy -- Periodicals; Epilepsy -- Periodicals; Seizures -- Periodicals; Épilepsie -- Périodiques; Electronic journals; Electronic journals; 616.853
• DOI: 10.1016/j.seizure.2023.01.009
• Languages: English
• ISSNs: 1059-1311

Abstract

Abstract: Deep brain stimulation (DBS) of the thalamic nuclei for the treatment of drug-resistant epilepsy (DRE) has been investigated for decades. In recent years, DBS targeting the anterior nucleus of the thalamus (ANT) was approved by CE and FDA for the treatment of focal-onset DRE in light of the results from the multicentric randomized controlled SANTE trial. However, stereotactic targeting of thalamic nuclei is not straightforward because of the low contrast definition among thalamic nuclei on the current MRI sequences. When the FGATIR sequence is added to the preoperative MRI protocol, the mammillothalamic tract can be identified and used as a visible landmark to directly target ANT. According to the current evidence, the trans-ventricular trajectory allows the placement of stimulating contact into the nucleus more frequently than the trans-cortical trajectory. Another thalamic nucleus whose stimulation for the treatment of generalized DRE is receiving increasing attention is the centromedian nucleus (CM). CM-DBS seems to be particularly efficacious in patients suffering from Lennox-Gastault syndrome (LGS) and the recent monocentric randomized controlled ESTEL trial also described a beneficial "sweet-spot". However, CM targeting is still based on indirect stereotactic coordinates, since acquisition times and post-processing techniques of the actual MRI sequences are not applicable in clinical practice. Moreover, the results of the ESTEL trial await confirmation from similar studies accounting for epileptic syndromes other than LGS. Therefore, novel neuroimaging approaches are advisable to improve the surgical targeting of CM and potentially tailor the stimulation based on the patient's specific epileptic phenotype.