title: Clinical Benefit of 3 Tesla Magnetic Resonance Imaging Rescanning in Patients With Focal Epilepsy and Negative 1.5 Tesla Magnetic Resonance Imaging.
abstract: BACKGROUND
  Magnetic resonance imaging is an essential tool in the pre-surgical evaluation of patients with drug-resistant epilepsy.
  
  
  OBJECTIVE
  Our aim was to assess the value of re-imaging patients with focal drug-resistant epilepsy.
  
  
  METHODS
  Thirty patients with negative or non-conclusive 1.5 Tesla magnetic resonance imaging were rescanned with 1.5T and 3T. All of them had previous 1.5 scans with no seizure protocol in a non-specialized center. Two neuroradiologists who were blinded to prior imaging results randomly reviewed the magnetic resonance images. Kappa score was used to assess the reliability.
  
  
  RESULTS
  Mean age of patients was 30 (SD ± 11) years. The intra-observer agreement for the first radiologist was 0.74 for 1.5T and 0.71 for 3T. In the second radiologist it was 0.82 and 0.66, respectively. Three lesions (10%) were identified by general radiologists in non-specialized centers using a 1.5T standard protocol. In our center a consensus between two neuroradiologists using epilepsy protocol identified seven lesions (23%) using 1.5T and 10 (33%) using 3T (p < 0.01). In 28% of patients this additional information resulted in a change in clinical management.
  
  
  CONCLUSIONS
  3T magnetic resonance imaging rescanning improves the diagnostic yield in patients with focal epilepsy and previous negative 1.5T magnetic resonance imaging. Use of 3T magnetic resonance imaging, epilepsy protocols, and interpretation by experienced neuroradiologists is highly recommended.
authors.affiliation: Section of Neurology, Hospital Pablo Tobón Uribe, University of Antioquia, Medellín, Colombia.|Instituto de Alta Tecnología Médica (IATM), Medellín, Colombia.|Division of Neurology, University of Saskatchewan, Saskatoon, Canada.
authors.forename: Lady D
authors.initials: LD
authors.lastname: Ladino
authors.affiliation: Clínica Medellín, Medellín, Colombia.
authors.forename: Pedro
authors.initials: P
authors.lastname: Balaguera
authors.affiliation: Instituto de Alta Tecnología Médica (IATM), Medellín, Colombia.
authors.forename: Simon
authors.initials: S
authors.lastname: Rascovsky
authors.affiliation: Instituto de Alta Tecnología Médica (IATM), Medellín, Colombia.
authors.forename: Jorge
authors.initials: J
authors.lastname: Delgado
authors.affiliation: Instituto de Alta Tecnología Médica (IATM), Medellín, Colombia.
authors.forename: Juan
authors.initials: J
authors.lastname: Llano
authors.affiliation: Division of Neurology, University of Saskatchewan, Saskatoon, Canada.
authors.forename: Lizbeth
authors.initials: L
authors.lastname: Hernández-Ronquillo
authors.affiliation: Hospital Universitario San Vicente Fundación, Medellín, Colombia.
authors.forename: Bety
authors.initials: B
authors.lastname: Gómez-Arias
authors.affiliation: Division of Neurology, University of Saskatchewan, Saskatoon, Canada.
authors.forename: José F
authors.initials: JF
authors.lastname: Téllez-Zenteno
mesh_terms: D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D000069279:Drug Resistant Epilepsy / Q000000981:diagnostic imaging*; D004828:Epilepsies, Partial / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015588:Observer Variation; D011300:Preoperative Care / Q000379:methods; D011446:Prospective Studies; D015203:Reproducibility of Results; D055815:Young Adult