Abstract Details

Title Resting-state Functional Connectivity Changes with Microburst VNS Therapy Differ Between Focal and Generalized Epilepsy

Topic Epilepsy/Clinical Neurophysiology (EEG)

Presentation(s) P3 - Poster Session 3 (5:30 PM-6:30 PM)

Poster/Presentation
Number 1-010

Background

μVNS can reduce seizure frequency in TRE via targeted thalamic plasticity as potential mechanism of action. Relationships between thalamus rsFC and μVNS have not been explored. We hypothesized that thalamus rsFC would be associated with seizure frequency changes from μVNS.

Objective

To investigate effects of microburst vagus nerve stimulation (μVNS) on resting-state functional connectivity (rsFC) in treatment resistant epilepsy (TRE).

Design/Methods

18 focal (Foc_TRE) and 10 generalized (Gen_TRE) TRE patients with VNS underwent 3T resting-state fMRI at 2 weeks post-implantation (baseline) and after 6 months of μVNS (6mo_μVNS). Resting-state fMRI preprocessing and analyses were performed using in-house Matlab scripts. Nonparametric permutation tests assessed baseline group differences in region-of-interest rsFC between automated anatomical atlas (AAL) brain regions and baseline-to-6mo_μ_VNS rsFC changes (significant at p_corrected<0.05). Significant baseline differences prompted separate group longitudinal analyses. Z-scores were extracted for significant thalamus rsFC changes. Spearman correlations were performed between thalamus rsFC and percent change in seizures after 6 (PCHG-6) and 12 months (PCHG-12) of μVNS (significant at p<0.05).

Results

At baseline, Gen_TRE had higher correlation between AAL regions compared to Foc_TRE. Baseline-to-6mo_μVNS rsFC changes were few for Gen_TRE and numerous for Foc_TRE. Gen_TRE showed baseline-to-6mo_μ_VNS connectivity decrease between left thalamus and left superior parietal lobule. Foc_TRE showed baseline-to-6mo_μ_VNS connectivity increases between left thalamus and right middle cingulum (Lthal-Rmidcing), right and left angular gyrus (Lthal-Rangular; Lthal-Langular), and left precuneus (Lthal-Lprecuneus); right thalamus showed connectivity increases with left angular gyrus (Rthal-Langular). PCHG-6 and PCHG-12 were not significantly correlated with thalamus rsFC changes. Foc_TRE showed significant negative correlations between PCHG-12 and baseline rsFC for Lthal-Rmidcing (rho=-0.613; p=0.0069), Lthal-Rangular (rho=-0.506; p=0.0323) and Rthal-Langular (rho=-0.516; p=0.0283).

Conclusions

Baseline-to-6mo_μVNS rsFC changes differed between focal and generalized TRE. Baseline thalamus rsFC is associated with long-term seizure frequency reduction with μVNS in TRE. Larger samples are necessary to further assess these relationships.

Authors/Disclosures
Jane B. Allendorfer, PhD (U of Alabama At Birmingham, Neurology) PRESENTER	An immediate family member of Dr. Allendorfer has received personal compensation for serving as an employee of Northport Health Services, LLC. The institution of Dr. Allendorfer has received research support from National Institutes of Health. The institution of Dr. Allendorfer has received research support from Evelyn F. McKnight Brain Institute. The institution of Dr. Allendorfer has received research support from LivaNova, Inc. Dr. Allendorfer has received personal compensation in the range of $500-$4,999 for serving as a Speaker with Cleveland Clinic. Dr. Allendorfer has received personal compensation in the range of $0-$499 for serving as a Examiner with University of Auckland. Dr. Allendorfer has received personal compensation in the range of $500-$4,999 for serving as a Speaker with International League Against Epilepsy. Dr. Allendorfer has a non-compensated relationship as a Scientific Program Committee Member with American Epilepsy Society that is relevant to AAN interests or activities. Dr. Allendorfer has a non-compensated relationship as a Editorial Board Member with Epilepsy and Behavior Reports that is relevant to AAN interests or activities.
Jerzy P. Szaflarski, MD, PhD, FAAN (University of Alabama At Birmingham)	Dr. Szaflarski has received personal compensation in the range of $10,000-$49,999 for serving as a Consultant for UCB Pharma. Dr. Szaflarski has received personal compensation in the range of $10,000-$49,999 for serving as a Consultant for LivaNova Inc. Dr. Szaflarski has received personal compensation in the range of $500-$4,999 for serving as a Consultant for PureTech Health. Dr. Szaflarski has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Gidley, Sarli & Marusak, LLP. Dr. Szaflarski has received personal compensation in the range of $5,000-$9,999 for serving as an Editor, Associate Editor, or Editorial Advisory Board Member for Elsevier. Dr. Szaflarski has received personal compensation in the range of $5,000-$9,999 for serving as an Expert Witness for Law Firm. Dr. Szaflarski has stock in AdCel Biopharma, LLC. Dr. Szaflarski has stock in iFovea.
Rodolphe Nenert	No disclosure on file
Ellie Shamshiri, PhD (LivaNova)	Dr. Shamshiri has received personal compensation for serving as an employee of Livanova .
Giovanni Ranuzzi (LivaNova)	No disclosure on file
Jason Begnaud (LivaNova)	No disclosure on file
Ryan Verner	Ryan Verner has received personal compensation for serving as an employee of LivaNova USA Inc. Ryan Verner has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Sella Therapies. Ryan Verner has stock in LivaNova PLC.