Objective: The authors' goal was to prospectively quantify the impact of resting-state functional MRI (rs-fMRI) on pediatric epilepsy surgery planning.
Methods: Fifty-one consecutive patients (3 months to 20 years old) with intractable epilepsy underwent rs-fMRI for presurgical evaluation. The team reviewed the following available diagnostic data: video-electroencephalography (n = 51), structural MRI (n = 51), FDG-PET (n = 42), magnetoencephalography (n = 5), and neuropsychological testing (n = 51) results to formulate an initial surgery plan blinded to the rs-fMRI findings. Subsequent to this discussion, the connectivity results were revealed and final recommendations were established. Changes between pre- and post-rs-fMRI treatment plans were determined, and changes in surgery recommendation were compared using McNemar's test.
Results: Resting-state fMRI was successfully performed in 50 (98%) of 51 cases and changed the seizure onset zone localization in 44 (88%) of 50 patients. The connectivity results prompted 6 additional studies, eliminated the ordering of 11 further diagnostic studies, and changed the intracranial monitoring plan in 10 cases. The connectivity results significantly altered surgery planning with the addition of 13 surgeries, but it did not eliminate planned surgeries (p = 0.003). Among the 38 epilepsy surgeries performed, the final surgical approach changed due to rs-fMRI findings in 22 cases (58%), including 8 (28%) of 29 in which extraoperative direct electrical stimulation mapping was averted.
Conclusions: This study demonstrates the impact of rs-fMRI connectivity results on the decision-making for pediatric epilepsy surgery by providing new information about the location of eloquent cortex and the seizure onset zone. Additionally, connectivity results may increase the proportion of patients considered eligible for surgery while optimizing the need for further testing.
Keywords: DRE = drug-resistant epilepsy; EEG = electroencephalography; EPCC = epilepsy patient care conference; ICA = independent component analysis; MEG = magnetoencephalography; RNS = responsive neurostimulation; RSN = resting-state network; SOZ = seizure onset zone; VNS = vagus nerve stimulation; connectivity; epilepsy surgery; resting-state functional MRI; rs-fMRI = resting-state functional MRI; seizure; surgical candidacy; surgical technique.
Correlating Resting-State Functional Magnetic Resonance Imaging Connectivity by Independent Component Analysis-Based Epileptogenic Zones with Intracranial Electroencephalogram Localized Seizure Onset Zones and Surgical Outcomes in Prospective Pediatric Intractable Epilepsy Study.Brain Connect. 2017 Sep;7(7):424-442. doi: 10.1089/brain.2016.0479. Brain Connect. 2017. PMID: 28782373 Free PMC article.
Resting-state functional magnetic resonance imaging for surgical planning in pediatric patients: a preliminary experience.J Neurosurg Pediatr. 2017 Dec;20(6):583-590. doi: 10.3171/2017.6.PEDS1711. Epub 2017 Sep 29. J Neurosurg Pediatr. 2017. PMID: 28960172 Free PMC article.
Network-targeted approach and postoperative resting-state functional magnetic resonance imaging are associated with seizure outcome.Ann Neurol. 2019 Sep;86(3):344-356. doi: 10.1002/ana.25547. Epub 2019 Jul 11. Ann Neurol. 2019. PMID: 31294865 Clinical Trial.
Network Connectivity in Epilepsy: Resting State fMRI and EEG-fMRI Contributions.Front Neurol. 2014 Jul 4;5:93. doi: 10.3389/fneur.2014.00093. eCollection 2014. Front Neurol. 2014. PMID: 25071695 Free PMC article. Review.
Resting-state functional MRI in pediatric epilepsy surgery.Pediatr Neurosurg. 2013;49(5):261-73. doi: 10.1159/000363605. Epub 2014 Sep 24. Pediatr Neurosurg. 2013. PMID: 25277135 Review.