Localizing and tracking electrodes using stereovision in epilepsy cases

Xiaoyao Fan; Songbai Ji; David W. Roberts; Keith D. Paulsen

doi:10.1117/12.2082016

18 March 2015 Localizing and tracking electrodes using stereovision in epilepsy cases

Xiaoyao Fan, Songbai Ji, David W. Roberts, Keith D. Paulsen

Proceedings Volume 9415, Medical Imaging 2015: Image-Guided Procedures, Robotic Interventions, and Modeling; 94150G (2015) https://doi.org/10.1117/12.2082016
Event: SPIE Medical Imaging, 2015, Orlando, Florida, United States

Abstract

In epilepsy cases, subdural electrodes are often implanted to acquire intracranial EEG (iEEG) for seizure localization and resection planning. However, the electrodes may shift significantly between implantation and resection, during the time that the patient is monitored for iEEG recording. As a result, the accuracy of surgical planning based on electrode locations at the time of resection can be compromised. Previous studies have only quantified the electrode shift with respect to the skull, but not with respect to the cortical surface, because tracking cortical shift between surgeries is challenging. In this study, we use an intraoperative stereovision (iSV) system to visualize and localize the cortical surface as well as electrodes, record three-dimensional (3D) locations of the electrodes in MR space at the time of implantation and resection, respectively, and quantify the raw displacements, i.e., with respect to the skull. Furthermore, we track the cortical surface and quantify the shift between surgeries using an optical flow (OF) based motion-tracking algorithm. Finally, we compute the electrode shift with respect to the cortical surface by subtracting the cortical shift from raw measured displacements. We illustrate the method using one patient example. In this particular patient case, the results show that the electrodes not only shifted significantly with respect to the skull (8.79 ± 3.00 mm in the lateral direction, ranging from 2.88 mm to 12.87 mm), but also with respect to the cortical surface (7.20 ± 3.58 mm), whereas the cortical surface did not shift significantly in the lateral direction between surgeries (2.23 ± 0.76 mm).

Citation Download Citation

Xiaoyao Fan, Songbai Ji, David W. Roberts, and Keith D. Paulsen "Localizing and tracking electrodes using stereovision in epilepsy cases", Proc. SPIE 9415, Medical Imaging 2015: Image-Guided Procedures, Robotic Interventions, and Modeling, 94150G (18 March 2015); https://doi.org/10.1117/12.2082016

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
8 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Electrodes

Surgery

Skull

Visualization

Brain

Epilepsy

Magnetic resonance imaging

Show All Keywords

Keywords/Phrases

Search In:

Publication Years