Authors :
Presenting Author: Ammar Hussain, MD – Advent Health Epilepsy Center Orlando
James Baumgartner, MD – Advent Health Epilepsy Center Ortlando; Kihyeong Lee, MD – Advent Health Epilepsy Center Orlando; Joo Hee Seo, MD – Advent Health Epilepsy Center Orlando; Holly Skinner, DO – Advent Health Epilepsy Center Orlando; Elakkat Gireesh, MD – Advent Health Epilepsy Center Orlando; Angel Claudio, MD – Advent Health Epilepsy Center Orlando; Julia Henry, MD – Advent Health Epilepsy Center Orlando; Eduardo Castillo, Ph.D – Advent Health Epilepsy Center Orlando; Michael Westerveld, Ph.D – Advent Health Epilepsy Center Orlando; Amy Cummisky, PA – Advent Health Epilepsy Center Orlando; Po-Ching Chen, BioMed Engr – Advent Health Epilepsy Center Orlando
Rationale: Seizure freedom after frontal lobe resections among different studies ranges from 20 to 70% based on patient heterogeneity and surgical techniques. The potential morbidity may limit the surgical resection even for well demarcated epileptogenic lesions. The objective of this study is to evaluate effectiveness of tailored frontal disconnection (FD) in seizure control and surgical outcomes.
Methods: The authors conducted a retrospective analysis of clinical, electroencephalography, structural and functional brain imaging, histopathological, surgical and seizure outcome data of 35 consecutive patients (15 children, 20 adults) who underwent FD between 2012 to 2020.
Results: Seizure started between the ages of one month to 44 years with median epilepsy duration of 4.5 years. FD was performed between the ages of five months to 47 years including in five patients (14.2%) with prior failed surgical intervention. A total of 60% (21/35) patients had more than one seizure type with focal impaired awareness and generalized tonic clonic as the most common seizure types. Etiologies/risk factor included malformation of cortical development (n=9; 7 with TSC), acquired hemorrhagic brain injury (n=4), infectious (n=3), genetic (n=2), meningioma (n=1), autism/developmental delay (n=4). Ictal findings localized to unilateral fronto-temporal region in 14 patients (40%), bilateral in six (17.1%) and non-lateralizing in 15 (42.8%) patients. Brain MRI showed unilateral frontal epileptogenic lesion in 15 patients (42.8%), bilateral in 10 and normal findings in 10 patients (28.5%). PET hypometabolism in the ipsilateral frontotemporal region was noted in 18 patients (51.4%). Ictal hyperperfusion showed concordant ipsilateral findings in seven (20%) and Magnetoencephalography showed concordant source localization in 14 (40%) patients. Intracranial EEG was performed with unilateral subdural grids, depth electrodes or stereo EEG (n=18) and bilateral subdural grids, stereo EEG (n=15). Isolated FD was performed in eight patients (22.2%). FD combined with tailored resection of frontal and adjacent lobe with or without corpus callosotomy was performed in remaining patients. Transient perioperative complications occurred in six patients (17.1%). Overall, 51.5% patients (17/33) were seizure free at two year follow up. A total of 75% (6/8) patients with acquired pathology were seizure free compared to 44% (11/25) with developmental or unknown pathology. Histopathology showed focal cortical dysplasia in eight patients (22.8%). Neurological deficits included mild contralateral hemiparesis (n=9, 25.7%), transient disconnection, SMA syndrome (n=5, 15.1%), speech impairment (n=6, 18.1%) and behavioral problems (n=1), which remained stable over time.
Conclusions:
Customized FD is an effective and reasonably safe procedure in selected patients with complex frontal lobe epilepsy involving heterogenous anatamo-electro-clinical data.
Funding: none