title: Alpha-[11C]methyl-L-tryptophan uptake in patients with periventricular nodular heterotopia and epilepsy.
abstract: BACKGROUND
  Alpha-[11C]methyl-L-tryptophan (alpha-MTrp) positron emission tomography (PET) is a promising tool in the localization of the epileptogenic area in selected group of focal epilepsy patients. Electrophysiological evidence suggests the involvement of the neocortex in periventricular nodular heterotopia (PVNH).
  
  
  OBJECTIVE
  To determine whether alpha-MTrp PET can detect neocortical changes in patients with PVNH.
  
  
  METHODS
  Four patients (2 male, mean age 28, range 23-35 years) with PVNH and intractable seizures were studied. The functional image in each patient was compared with those from 21 healthy controls (mean age 34.6 +/- 14.2 years) by using statistical parametric mapping (SPM). The location of increased alpha-MTrp uptake was compared with the location of the EEG focus. A significant cluster was defined as a cluster with a height p = 0.005 and an extent threshold 100.
  
  
  RESULTS
  Alpha-MTrp PET revealed increased cortical uptake in two of four patients. The area of increased alpha-MTrp uptake in one patient was widespread. In the other patient, the area of increased uptake did not include the region where most seizures were generated on EEG. alpha-MTrp PET did not show increased uptake in the heterotopic nodules in any of the patients.
  
  
  CONCLUSIONS
  Alpha-MTrp PET suggests abnormal metabolism of tryptophan in the neocortex. The increased uptake may be diffuse and may not co-localize with the EEG focus. This preliminary study suggests that alpha-MTrp PET may be useful, in conjunction with other evaluations, in localizing epileptic focus in patients with PVNH and refractory seizures.
authors: Department of Pediatrics, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan.
authors: Jun
authors: J
authors: Natsume
authors: Neda
authors: N
authors: Bernasconi
authors: Yahya
authors: Y
authors: Aghakhani
authors: Yoshitaka
authors: Y
authors: Kumakura
authors: Masami
authors: M
authors: Nishikawa
authors: Marco
authors: M
authors: Fedi
authors: Lahbib
authors: L
authors: Soualmi
authors: François
authors: F
authors: Dubeau
authors: Frederick
authors: F
authors: Andermann
authors: Andrea
authors: A
authors: Bernasconi
authors: Mirko
authors: M
authors: Diksic
mesh_terms: D000328:Adult; D001931:Brain Mapping; D002250:Carbon Radioisotopes / Q000378:metabolism; D035061:Control Groups; D004569:Electroencephalography / Q000706:statistics & numerical data; D004827:Epilepsy / Q000000981:diagnostic imaging* / Q000378:metabolism; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D019579:Neocortex / Q000378:metabolism / Q000503:physiopathology; D054091:Periventricular Nodular Heterotopia / Q000000981:diagnostic imaging* / Q000378:metabolism; D049268:Positron-Emission Tomography / Q000706:statistics & numerical data; D012701:Serotonin / Q000378:metabolism; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D002250:Carbon Radioisotopes; C020774:alpha-methyltryptophan; D012701:Serotonin; D014364:Tryptophan