title: Quantitative evaluation for brain CT/MRI coregistration based on maximization of mutual information in patients with focal epilepsy investigated with subdural electrodes.
abstract: Patients with drug-resistant focal epilepsy may require intracranial investigations with subdural electrodes. These must be correctly localized with respect to the brain cortical surface and require appropriate monitoring. For this purpose, coregistration techniques, which fuse preimplantation 3D magnetic resonance imaging scans with postimplantation computed tomography scans, have been implemented. In order to reduce localization errors due to the fusion process, we used a coregistration method based on the maximization of mutual information (MI) in 11 patients with extratemporal epilepsy who were invasively investigated. Our registration method is based on three processing steps: rigid-body transformation for coregistration, computation of MI as a similarity measure and the use of the Downhill Simplex optimization method. After consistency analysis, the shift of the registration method reached 0.14+/-0.27 mm in translation and 0.03+/-0.14 degrees in rotation, and the accuracies assessed on voxels of skull surface and voxels of the center of the brain volume were 1.42+/-0.61 and 1.15+/-0.53 mm, respectively. The accuracy of the fusion process reached submillimeter range, and results were considered reliable for surgical planning in all studied patients.
authors: MARBILab, Enrico Fermi Center, I-00179 Rome, Italy.
authors: Soléakhéna
authors: S
authors: Ken
authors: Giancarlo
authors: G
authors: Di Gennaro
authors: Giovanni
authors: G
authors: Giulietti
authors: Fabio
authors: F
authors: Sebastiano
authors: Diego
authors: D
authors: De Carli
authors: Girolamo
authors: G
authors: Garreffa
authors: Claudio
authors: C
authors: Colonnese
authors: Roberto
authors: R
authors: Passariello
authors: Jean-Albert
authors: JA
authors: Lotterie
authors: Bruno
authors: B
authors: Maraviglia
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology*; D003198:Computer Simulation; D004566:Electrodes; D004828:Epilepsies, Partial / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015203:Reproducibility of Results; D013355:Subdural Space / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods*