Background and Aims:

To assess magnetic resonance imaging (MRI) alterations occurring in patients with trigeminal neuralgia and to explore the predictive ability of MRI for initial radiosurgical outcome and long-term pain relief/recurrence after Gamma Knife radiosurgery (GKSRS).

Methods:

Thirty patients with idiopathic or classical TN, who underwent GKSRS and were followed for at least 24 months, were retrospectively included. Pre-treatment structural MRI and pre- and serial, post-operative clinical features were investigated. Fifteen age- and sex-matched healthy controls were also enrolled. Cortical thickness and gray matter (GM) volumes were assessed in TN patients relative to controls, as well as between patient subgroups according to treatment outcomes (initial responders/non-responders, patients with pain recurrence/long-lasting pain relief at the last follow-up). Clinical and MRI predictors of treatment outcomes were explored.

Results:

Cortical thinning of temporal, prefrontal, cingulate, somatosensory and occipital areas bilaterally was found in TN patients relative to controls. Patients who experienced TN recurrence after initial pain relief were characterized by thicker parahippocampal and temporal cortices bilaterally and greater volume of right amygdala and hippocampus compared to patients with long-lasting pain relief. In TN patients, disease duration and baseline cortical thinning of right parahippocampal, left fusiform and middle temporal cortices were associated with poor outcome after GKSRS at the last follow-up (R²=0.57, p<0.001).

Conclusions:

The study provides novel insights into structural brain alterations of TN patients, which might contribute to disease development and pain maintenance.

Background and Aims:

Parkinson’s disease (PD) patients are classified as tremor-dominant (TD) and postural instability and gait disorder (PIGD) phenotypes. The aim of this study was to investigate functional alterations within motor circuits of the cerebro-cerebellar system in PD-TD and PD-PIGD groups using stepwise functional connectivity (SFC) method.

Methods:

32 PD-TD and 26 PD-PIGD patients performed clinical/cognitive evaluations and resting-state functional MRI (fMRI). 60 age- and sex-matched controls were also enrolled. SFC analysis aims to characterize regions that connect to specific seed brain areas at different levels of link-step distances. The cerebellar seed-region was identified using motor task in 23 controls. For each of the SFC maps, two-sample t-test comparisons between groups were performed.

Results:

The performance of the fMRI-motor task was associated with activation of the lobule VI and vermis of the cerebellum. SFC analysis at one-link step distance showed, in both PD subtypes, a decreased connectivity between seed-region and thalamus and parietal lobe relative to controls; across intermediate link-steps, a reduced connectivity was observed with frontal, parietal and occipital lobes. Only PD-PIGD patients showed lower connectivity at intermediate link-step distances between the seed-cerebellar region and sensorimotor areas. Moreover, SFC pattern identified different localization of functional over‐connectivity in frontal lobe in both PD groups: inferior frontal gyrus and insula in PD-PIGD, and in orbitofrontal gyrus in PD-TD.

Conclusions:

These findings highlight subtype-specific PD changes in cerebellar functional connectivity, providing novel insights into the pathophysiological mechanism underlying different motor phenotypes.

Funding: Ministry of Education and Science Republic of Serbia (#175090), Italian Ministry of Health (#RF-2018-12366746).

Background and Aims:

To assess magnetic resonance imaging (MRI) alterations occurring in patients with trigeminal neuralgia and to explore the predictive ability of MRI for initial radiosurgical outcome and long-term pain relief/recurrence after Gamma Knife radiosurgery (GKSRS).

Methods:

Thirty patients with idiopathic or classical TN, who underwent GKSRS and were followed for at least 24 months, were retrospectively included. Pre-treatment structural MRI and pre- and serial, post-operative clinical features were investigated. Fifteen age- and sex-matched healthy controls were also enrolled. Cortical thickness and gray matter (GM) volumes were assessed in TN patients relative to controls, as well as between patient subgroups according to treatment outcomes (initial responders/non-responders, patients with pain recurrence/long-lasting pain relief at the last follow-up). Clinical and MRI predictors of treatment outcomes were explored.

Results:

Cortical thinning of temporal, prefrontal, cingulate, somatosensory and occipital areas bilaterally was found in TN patients relative to controls. Patients who experienced TN recurrence after initial pain relief were characterized by thicker parahippocampal and temporal cortices bilaterally and greater volume of right amygdala and hippocampus compared to patients with long-lasting pain relief. In TN patients, disease duration and baseline cortical thinning of right parahippocampal, left fusiform and middle temporal cortices were associated with poor outcome after GKSRS at the last follow-up (R²=0.57, p<0.001).

Conclusions:

The study provides novel insights into structural brain alterations of TN patients, which might contribute to disease development and pain maintenance.