Comparative magnetic resonance image-based evaluation of thalamotomy and pallidotomy lesion volumes

Document Type

Article

Abstract

Acute thalamotomy and pallidotomy lesion volumes based on magnetic resonance (MR) images were measured in 22 patients (11 thalamotomy and 11 pallidotomy patients). Thalamotomy inner lesion volumes (0.06 ± 0.04 ml; thermocoagulative zone) were smaller than pallidotomy inner lesion volumes (0.14 ± 0.08 ml) as determined using T1-weighted 3D-MPRAGE (1.5-mm slice spacing). Similar results were found using T1-weighted (6-mm slice spacing) image sets (0.09 ± 0.05 ml, thalamotomy; 0.13 ± 0.05 ml, pallidotomy). No differences were found when comparing thalamic or pallidal inner lesion volumes when the comparison was based on T2 weighted images. Thalamotomy total lesion volumes (thermocoagulative and surrounding edematous zones) were less than pallidotomy total lesion volumes independent of the MR protocol. The difference in thalamotomy and pallidotomy lesion volumes is most likely based on the distance between each discrete lesion placed along the lesioning tracts. In 7 of 11 thalamotomies, this distance was 1 mm with the remaining having 2 mm between each discrete lesion. All pallidotomy discrete lesions were 2 mm apart. More overlap between discrete lesioning sites for thalamotomies is likely to produce reduced lesion volumes.

Publication Date

1-1-1998

Publication Title

Stereotactic and Functional Neurosurgery

ISSN

10116125

Volume

71

Issue

3

First Page

131

Last Page

144

PubMed ID

10420146

Digital Object Identifier (DOI)

10.1159/000029656

Share

COinS