Normalization of aberrant pretherapeutic dynamic functional connectivity of extrastriate visual system in patients who underwent thalamotomy with stereotactic radiosurgery for essential tremor: a resting-state functional MRI study.

TitreNormalization of aberrant pretherapeutic dynamic functional connectivity of extrastriate visual system in patients who underwent thalamotomy with stereotactic radiosurgery for essential tremor: a resting-state functional MRI study.
Publication TypeJournal Article
Year of Publication2019
AuthorsTuleasca, C, Bolton, TAW, Régis, J, Najdenovska, E, Witjas, T, Girard, N, Delaire, F, Vincent, M, Faouzi, M, Thiran, J-P, Cuadra, MBach, Levivier, M, Van De Ville, D
JournalJournal of neurosurgery
Date Published05/2019
Mots-clésADL = activities of daily living, BA = Brodmann area, BOLD = blood oxygenation level–dependent, CAP = coactivation pattern, CHU = Centre Hospitalier Universitaire, coactivation pattern analysis, dFC = dynamic functional connectivity, DMN = default mode network, DTI = diffusion tensor imaging, ET = essential tremor, extrastriate, fMRI = functional MRI, functional magnetic resonance imaging, functional neurosurgery, GMD = gray matter density, HC = healthy control, PCC = posterior cingulate cortex, QUEST = Quality of Life in Essential Tremor, Radiosurgery, resting state, ROI = region of interest, SRS-T = stereotactic radiosurgery thalamotomy, thalamotomy, TSTH = tremor score on the treated hand, ventral intermediate nucleus, Vim = ventral intermediate nucleus, visual

OBJECTIVE: The tremor circuitry has commonly been hypothesized to be driven by one or multiple pacemakers within the cerebello-thalamo-cortical pathway, including the cerebellum, contralateral motor thalamus, and primary motor cortex. However, previous studies, using multiple methodologies, have advocated that tremor could be influenced by changes within the right extrastriate cortex, at both the structural and functional level. The purpose of this work was to evaluate the role of the extrastriate cortex in tremor generation and further arrest after left unilateral stereotactic radiosurgery thalamotomy (SRS-T).

METHODS: The authors considered 12 healthy controls (HCs, group 1); 15 patients with essential tremor (ET, right-sided, drug-resistant; group 2) before left unilateral SRS-T; and the same 15 patients (group 3) 1 year after the intervention, to account for delayed effects. Blood oxygenation level-dependent functional MRI during resting state was used to characterize the dynamic interactions of the right extrastriate cortex, comparing HC subjects against patients with ET before and 1 year after SRS-T. In particular, the authors applied coactivation pattern analysis to extract recurring whole-brain spatial patterns of brain activity over time.

RESULTS: The authors found 3 different sets of coactivating regions within the right extrastriate cortex in HCs and patients with pretherapeutic ET, reminiscent of the "cerebello-visuo-motor," "thalamo-visuo-motor" (including the targeted thalamus), and "basal ganglia and extrastriate" networks. The occurrence of the first pattern was decreased in pretherapeutic ET compared to HCs, whereas the other two patterns showed increased occurrences. This suggests a misbalance between the more prominent cerebellar circuitry and the thalamo-visuo-motor and basal ganglia networks. Multiple regression analysis showed that pretherapeutic standard tremor scores negatively correlated with the increased occurrence of the thalamo-visuo-motor network, suggesting a compensatory pathophysiological trait. Clinical improvement after SRS-T was related to changes in occurrences of the basal ganglia and extrastriate cortex circuitry, which returned to HC values after the intervention, suggesting that the dynamics of the extrastriate cortex had a role in tremor generation and further arrest after the intervention.

CONCLUSIONS: The data in this study point to a broader implication of the visual system in tremor generation, and not only through visual feedback, given its connections to the dorsal visual stream pathway and the cerebello-thalamo-cortical circuitry, with which its dynamic balance seems to be a crucial feature for reduced tremor. Furthermore, SRS-T seems to bring abnormal pretherapeutic connectivity of the extrastriate cortex to levels comparable to those of HC subjects.

Alternate URL

Alternate JournalJ. Neurosurg.
Citation Key / SERVAL ID9586
Peer reviewRefereed
PubMed ID31075777


Institut universitaire de médecine sociale et préventive
Route de la Corniche 10, 1010 Lausanne - Switzerland
+41 21 314 72 72 |

Go to top