title: PET/MRI and PET/MRI/SISCOM coregistration in the presurgical evaluation of refractory focal epilepsy.
abstract: We aimed to investigate the usefulness of coregistration of positron emission tomography (PET) and magnetic resonance imaging (MRI) findings (PET/MRI) and of coregistration of PET/MRI with subtraction ictal single-photon emission computed tomography (SPECT) coregistered to MRI (SISCOM) (PET/MRI/SISCOM) in localizing the potential epileptogenic zone in patients with drug-resistant epilepsy. We prospectively included 35 consecutive patients with refractory focal epilepsy whose presurgical evaluation included a PET study. Separately acquired PET and structural MRI images were coregistered for each patient. When possible, ictal SPECT and SISCOM were obtained and coregistered with PET/MRI. The potential location of the epileptogenic zone determined by neuroimaging was compared with the seizure onset zone determined by long-term video-EEG monitoring and with invasive EEG studies in patients who were implanted. Structural MRI showed no lesions in 15 patients. In these patients, PET/MRI coregistration showed a hypometabolic area in 12 (80%) patients that was concordant with seizure onset zone on EEG in 9. In 7 patients without MRI lesions, PET/MRI detected a hypometabolism that was undetected on PET alone. SISCOM, obtained in 25 patients, showed an area of hyperperfusion concordant with the seizure onset zone on EEG in 7 (58%) of the 12 of these patients who had normal MRI findings. SISCOM hyperperfusion was less extensive than PET hypometabolism. A total of 19 patients underwent surgery; 11 of these underwent invasive-EEG monitoring and the seizure onset zone was concordant with PET/MRI in all cases. PET/MRI/SISCOM coregistration, performed in 4 of these patients, was concordant in 3 (75%). After epilepsy surgery, 13 (68%) patients are seizure-free after a mean follow-up of 4.5 years. PET/MRI and PET/MRI/SISCOM coregistration are useful for determining the potential epileptogenic zone and thus for planning invasive EEG studies and surgery more precisely, especially in patients without lesions on MRI.
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain; Neurology Unit, Medical Division, Hospital Plató, Barcelona, Spain. Electronic address: santiago.fernandez@hospitalplato.com.
authors.forename: S
authors.initials: S
authors.lastname: Fernández
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: DONAIRE@clinic.ub.es.
authors.forename: A
authors.initials: A
authors.lastname: Donaire
authors.affiliation: Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: eulalia.seresroig@epfl.ch.
authors.forename: E
authors.initials: E
authors.lastname: Serès
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: SETOAIN@clinic.ub.es.
authors.forename: X
authors.initials: X
authors.lastname: Setoain
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: BARGALLO@clinic.ub.es.
authors.forename: N
authors.initials: N
authors.lastname: Bargalló
authors.affiliation: Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: CFALCON@clinic.ub.es.
authors.forename: C
authors.initials: C
authors.lastname: Falcón
authors.affiliation: Pediatric Epilepsy Unit, Hospital Sant Joan de Déu, Barcelona, Spain. Electronic address: Sanmarti@hsjdbcn.org.
authors.forename: F
authors.initials: F
authors.lastname: Sanmartí
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: iratxe.maestrosaiz@osakidetza.net.
authors.forename: I
authors.initials: I
authors.lastname: Maestro
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: JRUMIA@clinic.ub.es.
authors.forename: J
authors.initials: J
authors.lastname: Rumià
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: LPINTOR@clinic.ub.es.
authors.forename: L
authors.initials: L
authors.lastname: Pintor
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: BOGET@clinic.ub.es.
authors.forename: T
authors.initials: T
authors.lastname: Boget
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: JAPARICI@clinic.ub.es.
authors.forename: J
authors.initials: J
authors.lastname: Aparicio
authors.affiliation: Epilepsy Unit, Hospital Clinic de Barcelona, Barcelona, Spain; Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic de Barcelona, Barcelona, Spain. Electronic address: MCARRENO@clinic.ub.es.
authors.forename: M
authors.initials: M
authors.lastname: Carreño
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D001931:Brain Mapping / Q000379:methods; D002560:Cerebrovascular Circulation / Q000502:physiology; D002648:Child; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D049268:Positron-Emission Tomography / Q000379:methods*; D011300:Preoperative Care / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D012640:Seizures / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014741:Video Recording; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Multimodal imaging; PET/MRI coregistration; Refractory epilepsy; SISCOM