title: Augment low-field intra-operative MRI with preoperative MRI using a hybrid non-rigid registration method.
abstract: BACKGROUND
  Preoperatively acquired diffusion tensor image (DTI) and blood oxygen level dependent (BOLD) have been proved to be effective in providing more anatomical and functional information; however, the brain deformation induced by brain shift and tumor resection severely impairs the correspondence between the image space and the patient space in image-guided neurosurgery.
  
  
  METHODS
  To address the brain deformation, we developed a hybrid non-rigid registration method to register high-field preoperative MRI with low-field intra-operative MRI in order to recover the deformation induced by brain shift and tumor resection. The registered DTI and BOLD are fused with low-field intra-operative MRI for image-guided neurosurgery.
  
  
  RESULTS
  The proposed hybrid registration method was evaluated by comparing the landmarks predicted by the hybrid registration method with the landmarks identified in the low-field intra-operative MRI for 10 patients. The prediction error of the hybrid method is 1.92±0.54 mm, and the compensation accuracy is 74.3±5.0%. Compared to the landmarks far from the resection region, those near the resection region demonstrated a higher compensation accuracy (P-value=.003) although these landmarks had larger initial displacements.
  
  
  CONCLUSIONS
  The proposed hybrid registration method is able to bring preoperatively acquired BOLD and DTI into the operating room and compensate for the deformation to augment low-field intra-operative MRI with rich anatomical and functional information.
authors.affiliation: Glioma Surgery Division, Neurological Surgery Department, Huashan Hospital, Shanghai Medical College, Fudan University, PR China.
authors.forename: Chengjun
authors.initials: C
authors.lastname: Yao
authors.affiliation: Radiology and Imaging Sciences, National Institutes of Health, PR China.
authors.forename: Yixun
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Radiology and Imaging Sciences, National Institutes of Health, PR China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Yao
authors.affiliation: Glioma Surgery Division, Neurological Surgery Department, Huashan Hospital, Shanghai Medical College, Fudan University, PR China.
authors.forename: Dongxiao
authors.initials: D
authors.lastname: Zhuang
authors.affiliation: Glioma Surgery Division, Neurological Surgery Department, Huashan Hospital, Shanghai Medical College, Fudan University, PR China. Electronic address: wjsongc@126.com.
authors.forename: Jinsong
authors.initials: J
authors.lastname: Wu
authors.affiliation: Glioma Surgery Division, Neurological Surgery Department, Huashan Hospital, Shanghai Medical College, Fudan University, PR China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Qin
authors.affiliation: Glioma Surgery Division, Neurological Surgery Department, Huashan Hospital, Shanghai Medical College, Fudan University, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Mao
authors.affiliation: Glioma Surgery Division, Neurological Surgery Department, Huashan Hospital, Shanghai Medical College, Fudan University, PR China. Electronic address: lfzhouc@126.com.
authors.forename: Liangfu
authors.initials: L
authors.lastname: Zhou
mesh_terms: D000328:Adult; D000368:Aged; D001931:Brain Mapping / Q000379:methods*; D001932:Brain Neoplasms / Q000473:pathology* / Q000601:surgery*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D011300:Preoperative Care / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D025321:Surgery, Computer-Assisted / Q000379:methods*; D055815:Young Adult
keywords: Brain deformation; Free-form deformation; Low-field intra-operative MRI; Non-rigid registration; fMRI