title: Stereotactic ventrolateral thalamotomy: is ventriculography necessary?
abstract: In the computed tomography/magnetic resonance imaging (CT/MRI) era, the need for ventriculography to perform ventrolateral thalamotomy accurately has been debated. We retrospectively compared CT/MRI-derived coordinates for ventrolateral thalamotomy with the final lesion coordinates that were determined by ventriculography and microelectrode recording in 74 thalamotomies performed from 1984 to 1994. The median three-dimensional distance between the CT/MRI-derived loci and the ventriculography/microelectrode loci was 4.7 mm (range, 1.0-11.7 mm). The techniques correlated least along the Y axis (median, -0.3 mm; range, -8.2 to 8.0 mm). Correlation along the X axis was most consistent (median, 0.5 mm; range, -4.2 to 5.0 mm). Since 1990, the CT/MRI-derived coordinates have been generated by a multimodality correlative imaging technique (MCIT). A comparison of thalamotomies performed with and without the MCIT revealed a significant improvement in the correlation of CT/MRI- and ventriculography/microelectrode-derived coordinates when the MCIT was employed. The greatest improvement was noted along the Y axis where the median absolute difference was reduced from 4.0 to 1.8 mm (P = 0.0001). The result was a statistically significant reduction in the median three-dimensional distance from 5.6 to 3.7 mm (P = 0.0007). The authors conclude that thalamotomies can be safely and effectively performed without ventriculography when the MCIT is employed and supported by neurophysiological monitoring.
authors.affiliation: Department of Neurological Surgery, New York University Medical Center, New York, USA.
authors.forename: R L
authors.initials: RL
authors.lastname: Alterman
authors.forename: B A
authors.initials: BA
authors.lastname: Kall
authors.forename: H
authors.initials: H
authors.lastname: Cohen
authors.forename: P J
authors.initials: PJ
authors.lastname: Kelly
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014695:Cerebral Ventriculography / Q000295:instrumentation*; D002648:Child; D004569:Electroencephalography / Q000295:instrumentation; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D008839:Microelectrodes; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation; D010300:Parkinson Disease / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D012189:Retrospective Studies; D013238:Stereotaxic Techniques / Q000295:instrumentation*; D013787:Thalamic Nuclei / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*; D016896:Treatment Outcome; D014202:Tremor / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*