Technology Report

CT/MR Image Fusion in the Postoperative Assessment of Electrodes Implanted for Deep Brain Stimulation
Ruth L. O'Gorman^a, Josef M. Jarosz^a, Michael Samuel^b, Chris Clough^b, Richard P. Selway^c, Keyoumars Ashkan^c

Departments of
^aNeuroradiology,
^bNeurology, and
^cNeurosurgery, King's College Hospital, London, UK

Address of Corresponding Author

Stereotact Funct Neurosurg 2009;87:205-210 (DOI: 10.1159/000225973)

  Key Words

• Deep brain stimulation
• CT/MR image fusion
• Image registration

  Abstract

Background/Aims: Stereotactic postoperative imaging is essential for verification of the position of electrodes implanted for deep brain stimulation (DBS). MRI offers superior visualisation of the DBS targets relative to CT, but previous adverse incidents have heightened concerns about risks of postoperative MRI. Preoperative MRI fused with postoperative CT offers an alternative method for evaluating electrode position, but before this method can be clinically applied, the image registration accuracy must be established. The purpose of this study was to quantitatively assess the accuracy of three different image registration and fusion methods. Methods: Preoperative stereotactic MRI and postoperative stereotactic CT were acquired from 20 patients under- going DBS surgery (35 electrodes in total). The postoperative CT was registered and fused with the preoperative MRI, using three different registration algorithms. The position of each electrode tip was determined in stereotactic coordinates both in the (unfused) postoperative CT and the fused CT/MRI. The difference in tip position between the CT and fused CT/MRI was used to evaluate the registration accuracy. Results: The mean error along the lateral, anteroposterior, and vertical axes was 0.5, 0.5, and 1 mm, respectively. Conclusions: CT/MRI fusion provides a safe, practical technique for postoperative identification of DBS electrodes.

Copyright © 2009 S. Karger AG, Basel

  Author Contacts

Dr. R. O'Gorman
Department of Neuroradiology, Ground floor, Ruskin Wing, King's College Hospital
London SE5 9RS (UK)
Tel. +44 203 299 9000, ext. 4898, Fax +44 203 299 3120
E-Mail r.o'gorman@iop.kcl.ac.uk

  Article Information

Published online: June 26, 2009
Number of Print Pages : 6
Number of Figures : 2, Number of Tables : 2, Number of References : 26