title: Patient-specific detection of cerebral blood flow alterations as assessed by arterial spin labeling in drug-resistant epileptic patients.
abstract: Electrophysiological and hemodynamic data can be integrated to accurately and precisely identify the generators of abnormal electrical activity in drug-resistant focal epilepsy. Arterial Spin Labeling (ASL), a magnetic resonance imaging (MRI) technique for quantitative noninvasive measurement of cerebral blood flow (CBF), can provide a direct measure of variations in cerebral perfusion associated with the epileptic focus. In this study, we aimed to confirm the ASL diagnostic value in the identification of the epileptogenic zone, as compared to electrical source imaging (ESI) results, and to apply a template-based approach to depict statistically significant CBF alterations. Standard video-electroencephalography (EEG), high-density EEG, and ASL were performed to identify clinical seizure semiology and noninvasively localize the epileptic focus in 12 drug-resistant focal epilepsy patients. The same ASL protocol was applied to a control group of 17 healthy volunteers from which a normal perfusion template was constructed using a mixed-effect approach. CBF maps of each patient were then statistically compared to the reference template to identify perfusion alterations. Significant hypo- and hyperperfused areas were identified in all cases, showing good agreement between ASL and ESI results. Interictal hypoperfusion was observed at the site of the seizure in 10/12 patients and early postictal hyperperfusion in 2/12. The epileptic focus was correctly identified within the surgical resection margins in the 5 patients who underwent lobectomy, all of which had good postsurgical outcomes. The combined use of ESI and ASL can aid in the noninvasive evaluation of drug-resistant epileptic patients.
authors.affiliation: Clinical Neurophysiology and Functional Neuroimaging Unit, Department of Neurological and Movement Sciences, University of Verona, Verona, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Boscolo Galazzo
authors.affiliation: Department of Computer Science, University of Verona, Verona, Italy.
authors.forename: Silvia Francesca
authors.initials: SF
authors.lastname: Storti
authors.affiliation: Clinical Neurophysiology and Functional Neuroimaging Unit, Department of Neurological and Movement Sciences, University of Verona, Verona, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Del Felice
authors.affiliation: Neuroradiology Unit, Department of Diagnostic and Pathology, University Hospital Verona, Verona, Italy.
authors.forename: Francesca Benedetta
authors.initials: FB
authors.lastname: Pizzini
authors.affiliation: Clinical Neurophysiology and Functional Neuroimaging Unit, Department of Neurological and Movement Sciences, University of Verona, Verona, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Arcaro
authors.affiliation: Department of Neurophysiology, Foundation IRCCS San Camillo Hospital, Venice, Italy.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Formaggio
authors.affiliation: Epilepsy Surgery Center, Niguarda Hospital, Milan, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Mai
authors.affiliation: Institute of Biomedical Engineering, University of Oxford, Oxford, United Kingdom.
authors.forename: Michael
authors.initials: M
authors.lastname: Chappell
authors.affiliation: Neuroradiology Unit, Department of Diagnostic and Pathology, University Hospital Verona, Verona, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Beltramello
authors.affiliation: Clinical Neurology Unit, Department of Medical Science, Surgery and Health, University of Trieste, Trieste, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Manganotti
mesh_terms: D000328:Adult; D002560:Cerebrovascular Circulation; D000069279:Drug Resistant Epilepsy / Q000175:diagnosis / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013113:Spin Labels; D014741:Video Recording
chemical_list: D013113:Spin Labels