The accuracy and reliability of 3D CT/MRI co-registration in planning epilepsy surgery

• Published in: Clinical neurophysiology Vol. 120; no. 4; pp. 748 - 753
• Main Authors: Tao, James X, Hawes-Ebersole, Susan, Baldwin, Maria, Shah, Sona, Erickson, Robert K, Ebersole, John S
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ireland Ltd 01.04.2009; Elsevier
• Subjects: Adolescent; Adult; Biological and medical sciences; Co-registration; Electrodiagnosis. Electric activity recording; Electroencephalography; Epilepsies, Partial - pathology; Epilepsies, Partial - surgery; Epilepsy surgery; Female; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Humans; Imaging, Three-Dimensional - methods; Intra-operative digital photography; Investigative techniques, diagnostic techniques (general aspects); Magnetic Resonance Imaging - methods; Male; Medical sciences; Middle Aged; Nervous system; Nervous system (semeiology, syndromes); Neurology; Patient Care Planning; Photography; Preoperative Care; Registries; Reproducibility of Results; Sensitivity and Specificity; Subdural electrodes; Temporal lobe epilepsy; Tomography, X-Ray Computed - methods; Young Adult; Co-registration; Temporal lobe epilepsy; Subdural electrodes; Epilepsy surgery; Intra-operative digital photography; Human; Evaluation; Subdural; Nervous system diseases; Resection; Implant; Central nervous system; Epileptic focus; Complex partial epilepsy; Nuclear magnetic resonance imaging; Cerebral disorder; Electrodes; Accuracy; Central nervous system disease; Planning; Technique; Reliability; Localization
• ISSN: 1388-2457; 1872-8952
• DOI: 10.1016/j.clinph.2009.02.002

Abstract Objective To investigate the accuracy and reliability of 3D CT/MRI co-registration technique for the localization of implanted subdural electrodes in the routine epilepsy presurgical evaluation, in so doing assess its usefulness in planning the tailored resection of epileptic focus. Methods Four external anatomic fiducial makers were used for co-registration of volumetric pre-implant brain MRI and post-implant head CT using Curry 5.0 software in 19 epilepsy presurgical candidates. The location of subdural electrodes derived from the co-registration was compared to that obtained by intra-operative digital photographs by using gyral/sulcal patterns and cortical vasculature as anatomic markers. Results The mean localization error was 4.3 ± 2.5 mm in all 19 patients. However, the mean localization error was 3.1 ± 1.3 mm in 13 patients with all four reliable fiducial markers; whereas the mean localization error was 6.8 ± 2.4 mm in 6 patients with two or three reliable fiducial markers. Conclusion Visualization of subdural electrode positions on a patient’s cortex can be accurately performed in the routine clinical setting by 3D CT/MRI co-registration. However, the accuracy of co-registration is dependent upon having reliable surface fiducial markers. In practice, confirmation of location accuracy, such as with intra-operative digital photographs, is necessary for planning of tailored resective surgery. Significance The combination of 3D CT/MRI co-registration and intra-operative digital photography techniques provides a practical and effective algorithm for the localization and validation of implanted subdural electrodes.