Authors :
Presenting Author: Basanagoud Mudigoudar, MD – UTHSC
Sarah Weatherspoon, MD – University of Tennessee Health Science Center
Amy McGregor, MD – UTHSC
Nitish Chourasia, MD – UTHSC
Shalini Narayana, PhD – University of Tennessee Health Science Center and Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, TN, USA
Negar Noorizadeh, Ph.D. – University of Tennessee Health Science Center and Le Bonheur Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, TN, USA
Roozbeh Rezaie, PhD – UTHSC
James Wheless, BScPharm, MD, FAAP, FACP, FAAN, FAES, FCNS – University of Tennessee Health Science Center and Le Bonheur Children's Hospital
Nir Shimony, MD – University of Tennessee Health Science Center
Rationale:
Medically refractory epilepsy affects approximately one-third of patients with epilepsy, despite advances in treatment. Thalamic neuromodulation has emerged as a promising therapeutic option for drug-resistant epilepsy. There is a growing trend toward the use of thalamic responsive neurostimulation (RNS) in this context. Among thalamic targets, the anterior nucleus (ANT), centromedian nucleus (CM), and pulvinar nucleus (PULV) have the most robust clinical evidence supporting their efficacy. However, data on the safety and tolerability of thalamic RNS remain limited, particularly in pediatric populations.
Methods:
A retrospective chart review was conducted on all patients who underwent RNS implantation at the Le Bonheur Comprehensive Epilepsy Program. Only patients with thalamic lead placements were included in the analysis. Data collected included age at implantation, thalamic stimulation targets, complications, length of follow-up, and reported side effects.
Results:
A total of 27 patients underwent RNS implantation with leads targeting thalamic nuclei. The age at implantation ranged from 11 to 46 years, with 13 individuals (48%) under the age of 18 years. Nineteen patients received bilateral implants in the CM nuclei, three in the PULV nuclei, and two in the ATN. One patient had leads placed in the left ATN and right PULV nuclei, while two patients received implants in the right CM and right PULV nuclei. The follow-up period ranged from 2 to 23 months. Eighteen patients (66%) reported transient headaches following implantation, all of which resolved completely by the two-week follow-up visit. Two patients with bilateral CM implants experienced drowsiness lasting for 48 to 72 hours post-procedure. In one of these patients, postoperative imaging was normal; the other was found to have a hemorrhage in the left thalamus and along the electrode track within 24 hours of implantation. This patient also developed right-sided hemiparesis and dysphagia, necessitating gastrostomy tube placement. One adult patient with bilateral CM leads developed transient right-sided hemiparesis immediately after the procedure, which completely resolved after two weeks. Postoperative imaging of this patient revealed no abnormality. Another patient developed a scalp wound infection around the leads, requiring surgical intervention, although device explantation was not necessary. Paresthesia, characterized by tingling or numbness in the face, neck, or extremities, was reported in five patients (18%), all of whom had implants in the CM nuclei. Additionally, one patient with bilateral CM leads experienced transient foot twitching.
Conclusions:
In this cohort, thalamic RNS implantation demonstrated a manageable safety profile. While most patients tolerated the procedure well, transient adverse effects, such as headaches and paresthesia, were relatively common but largely self-limited. Serious complications, including hemorrhage and infection, were rare but underscore the need for careful monitoring.
Funding: None