Correlation of active contact location with weight gain after subthalamic nucleus deep brain stimulation: a case series

Unilateral focused ultrasound subthalamotomy in early Parkinson's disease: a pilot study

BACKGROUND

Unilateral focused ultrasound subthalamotomy (FUS-STN) improves motor features of Parkinson's disease (PD) in moderately advanced patients. The less invasive nature of FUS makes its early application in PD feasible. We aim to assess the safety and efficacy of unilateral FUS-STN in patients with PD of less than 5 years from diagnosis (early PD).

METHODS

Prospective, open-label study. Eligible patients with early PD had highly asymmetrical cardinal features. The primary outcome was safety, defined as treatment-related adverse events at 6 months. Secondary outcomes included efficacy, assessed as motor improvement in the Movement Disorders Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS), motor fluctuations, non-motor symptoms, daily living activities, quality of life, medication and patients' impression of change.

RESULTS

Twelve patients with PD (median age 52.0 (IQR 49.8-55.3) years, median time from diagnosis 3.0 (2.1-3.9) years) underwent unilateral FUS-STN. Within 2 weeks after treatment, five patients developed dyskinesia on the treated side, all resolved after levodopa dose adjustment. One patient developed mild contralateral motor weakness which fully resolved in 4 weeks. One patient developed dystonic foot and another hand and foot dystonia. The latter impaired gait and became functionally disabling initially. Both cases were well controlled with botulinum toxin injections. The off-medication motor MDS-UPDRS score for the treated side improved at 12 months by 68.7% (from 14.5 to 4.0, p=0.002), and the total motor MDS-UPDRS improved by 49.0% (from 26.5 to 13.0, p=0.002). Eleven patients (92%) reported global improvement 12 months after treatment.

CONCLUSION

Unilateral FUS-STN may be safe and effective to treat motor manifestations in patients with early PD. A larger confirmatory trial is warranted.

TRIAL REGISTRATION NUMBER

NCT04692116.

Mechanisms and consequences of weight gain after deep brain stimulation of the subthalamic nucleus in patients with Parkinson's disease

Body weight gain in combination with metabolic alterations has been observed after deep brain stimulation (DBS) of subthalamic nucleus (STN) in patients with Parkinson's disease (PD), which potentially counteracts the positive effects of motor improvement. We aimed to identify stimulation-dependent effects on motor activities, body weight, body composition, energy metabolism, and metabolic blood parameters and to determine if these alterations are associated with the local impact of DBS on different STN parcellations. We assessed 14 PD patients who underwent STN DBS (PD-DBS) before as well as 6- and 12-months post-surgery. For control purposes, 18 PD patients under best medical treatment (PD-CON) and 25 healthy controls (H-CON) were also enrolled. Wrist actigraphy, body composition, hormones, and energy expenditure measurements were applied. Electrode placement in the STN was localized, and the local impact of STN DBS was estimated. We found that STN DBS improved motor function by ~ 40% (DBS ON, Med ON). Weight and fat mass increased by ~ 3 kg and ~ 3% in PD-DBS (all P ≤ 0.005). fT3 (P = 0.001) and insulin levels (P = 0.048) increased solely in PD-DBS, whereas growth hormone levels (P = 0.001), daily physical activity, and VO2 during walking were decreased in PD-DBS (all P ≤ 0.002). DBS of the limbic part of the STN was associated with changes in weight and body composition, sedentary activity, insulin levels (all P ≤ 0.040; all r ≥ 0.56), and inversely related to HOMA-IR (P = 0.033; r = - 0.62). Daily physical activity is decreased after STN DBS, which can contribute to weight gain and an unfavorable metabolic profile. We recommend actigraphy devices to provide feedback on daily activities to achieve pre-defined activity goals.

Subthalamic deep brain stimulation for refractory Gilles de la Tourette's syndrome: clinical outcome and functional connectivity

Background

Deep brain stimulation (DBS) is a promising novel approach for managing refractory Gilles de la Tourette’s syndrome (GTS). The subthalamic nucleus (STN) is the most common DBS target for treating movement disorders, and smaller case studies have reported the efficacy of bilateral STN-DBS treatment for relieving tic symptoms. However, management of GTS and treatment mechanism of STN-DBS in GTS remain to be elucidated.

Methods

Ten patients undergoing STN-DBS were included. Tics severity was evaluated using the Yale Global Tic Severity Scale. The severities of comorbid psychiatric symptoms of obsessive–compulsive behavior (OCB), attention-deficit/hyperactivity disorder, anxiety, and depression; social and occupational functioning; and quality of life were assessed. Volumes of tissue activated were used as seed points for functional connectivity analysis performed using a control dataset.

Results

The overall tics severity significantly reduced, with 62.9% ± 26.2% and 58.8% ± 27.2% improvements at the 6- and 12-months follow-up, respectively. All three patients with comorbid OCB showed improvement in their OCB symptoms at both the follow-ups. STN-DBS treatment was reasonably well tolerated by the patients with GTS. The most commonly reported side effect was light dysarthria. The stimulation effect of STN-DBS might regulate these symptoms through functional connectivity with the thalamus, pallidum, substantia nigra pars reticulata, putamen, insula, and anterior cingulate cortices.

Conclusions

STN-DBS was associated with symptomatic improvement in severe and refractory GTS without significant adverse events. The STN is a promising DBS target by stimulating both sensorimotor and limbic subregions, and specific brain area doses affect treatment outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11266-w.