Supplementary motor area (SMA) syndrome is defined as temporary paralysis after the resection of brain tumor localized in the SMA. Although in most cases paralysis induced by SMA resection resolves within a short period, the time until complete recovery varies and has not been precisely analyzed to date. In this study, the authors investigated factors for predicting the time required for recovery from paralysis after SMA resection.
Data from 20 cases were analyzed. All 20 patients (mean age 54.9 ± 12.6 years) had undergone resection of frontal lobe glioma involving the SMA. The severity of postoperative paralysis was recorded until complete recovery using the Brunnstrom recovery stage index. To investigate factors associated with recovery time, the authors performed multivariate analysis with the following potentially explanatory variables: age, severity of paralysis after the surgery, resected volume of the SMA, and probability of disconnection of fibers running through or near the SMA. Moreover, voxel-based lesion symptom analysis was performed to clarify the resected regions related to prolonged recovery.
In most cases of severe to moderate paralysis, there was substantial improvement within the 1st postoperative week, but 2–9 weeks were required for complete recovery. Significantly delayed recovery from paralysis was associated with resection of the cingulate cortex and its deep regions. The factors found to influence recovery time from paralysis were stage of paralysis at postoperative day 7 and disconnection probability of the cingulum (adjusted R2 = 0.63, p < 0.0001).
Recovery time from paralysis due to SMA syndrome can be predicted by the severity of paralysis at postoperative day 7 and degree of damage to the cingulum.
ABBREVIATIONSBRS = Brunnstrom recovery stage; FAT = frontal aslant tract; FST = fronto-striatal tract; MNI = Montreal Neurological Institute; POD = postoperative day; SMA = supplementary motor area; VLSM = voxel-based lesion-symptom mapping.
Correspondence Mitsutoshi Nakada: Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan. email@example.com.INCLUDE WHEN CITING Published online February 8, 2019; DOI: 10.3171/2018.10.JNS182391.Disclosures The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.