The subthalamic nucleus is the preferred neurosurgical target for deep-brain stimulation to treat cardinal motor features of Parkinson's disease. Focused ultrasound is an imaging-guided method for ...creating therapeutic lesions in deep-brain structures, including the subthalamic nucleus.
We randomly assigned, in a 2:1 ratio, patients with markedly asymmetric Parkinson's disease who had motor signs not fully controlled by medication or who were ineligible for deep-brain stimulation surgery to undergo focused ultrasound subthalamotomy on the side opposite their main motor signs or a sham procedure. The primary efficacy outcome was the between-group difference in the change from baseline to 4 months in the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) motor score (i.e., part III) for the more affected body side (range, 0 to 44, with higher scores indicating worse parkinsonism) in the off-medication state. The primary safety outcome (procedure-related complications) was assessed at 4 months.
Among 40 enrolled patients, 27 were assigned to focused ultrasound subthalamotomy (active treatment) and 13 to the sham procedure (control). The mean MDS-UPDRS III score for the more affected side decreased from 19.9 at baseline to 9.9 at 4 months in the active-treatment group (least-squares mean difference, 9.8 points; 95% confidence interval CI, 8.6 to 11.1) and from 18.7 to 17.1 in the control group (least-squares mean difference, 1.7 points; 95% CI, 0.0 to 3.5); the between-group difference was 8.1 points (95% CI, 6.0 to 10.3; P<0.001). Adverse events in the active-treatment group were dyskinesia in the off-medication state in 6 patients and in the on-medication state in 6, which persisted in 3 and 1, respectively, at 4 months; weakness on the treated side in 5 patients, which persisted in 2 at 4 months; speech disturbance in 15 patients, which persisted in 3 at 4 months; facial weakness in 3 patients, which persisted in 1 at 4 months; and gait disturbance in 13 patients, which persisted in 2 at 4 months. In 6 patients in the active-treatment group, some of these deficits were present at 12 months.
Focused ultrasound subthalamotomy in one hemisphere improved motor features of Parkinson's disease in selected patients with asymmetric signs. Adverse events included speech and gait disturbances, weakness on the treated side, and dyskinesia. (Funded by Insightec and others; ClinicalTrials.gov number, NCT03454425.).
Aim
Impulse‐control disorder is a common neuropsychiatric complication in Parkinson's disease (PD) under dopamine replacement therapy. Prior studies tested the balance between enhanced desire towards ...reward and cognitive control deficits, hypothesized to be biased towards the former in impulse control disorders. We provide evidence for this hypothesis by measuring behavioral and neural patterns behind the influence of sexual desire over response inhibition and tools towards functional restoration using repetitive transcranial stimulation in patients with hypersexuality as predominant impulsive disorder.
Methods
The effect of sexual cues on inhibition was measured with a novel erotic stop‐signal task under on and off dopaminergic medication. Task‐related functional and anatomical connectivity models were estimated in 16 hypersexual and 17 nonhypersexual patients with PD as well as in 17 healthy controls. Additionally, excitatory neuromodulation using intermittent theta‐burst stimulation (sham‐controlled) was applied over the pre‐supplementary motor area in 20 additional hypersexual patients with PD aiming to improve response inhibition.
Results
Compared with their nonhypersexual peers, patients with hypersexuality recruited caudate, pre‐supplementary motor area, ventral tegmental area, and anterior cingulate cortex while on medication. Reduced connectivity was found between pre‐supplementary motor area and caudate nucleus in hypersexual compared with nonhypersexual patients (while medicated), a result paralleled by compensatory enhanced anatomical connectivity. Furthermore, stimulation over the pre‐supplementary motor area improved response inhibition in hypersexual patients with PD when exposed to sexual cues.
Conclusion
This study, therefore, has identified a specific fronto‐striatal and mesolimbic circuitry underlying uncontrolled sexual responses in medicated patients with PD where cortical neuromodulation halts its expression.
Abstract
BACKGROUND
Transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) thalamotomy is a novel and effective treatment for controlling tremor in essential tremor patients.
OBJECTIVE
...To provide a comprehensive characterization of the radiological, topographical, and volumetric aspects of the tcMRgFUS thalamic lesion, and to quantify how they relate to the clinical outcomes.
METHODS
In this study, clinical and radiological data from forty patients with medically-refractory essential tremor treated with unilateral tcMRgFUS thalamotomy were retrospectively analyzed. Treatment efficacy was assessed with Clinical Rating Scale for Tremor (CRST). Lesions were manually segmented on T1, T2, and susceptibility-weighted images, and 3-dimensional topographical analysis was then carried out. Statistical comparisons were performed using nonparametric statistics.
RESULTS
The greatest clinical improvement was correlated with a more inferior and posterior lesion, a bigger lesion volume, and percentage of the ventral intermediate nucleus covered by the lesion; whereas, the largest lesions accounted for the occurrence of gait imbalance. Furthermore, the volume of the lesion was significantly predicted by the number of sonications surpassing 52°C.
CONCLUSION
Here we provide a comprehensive characterization of the thalamic tcMRgFUS lesion including radiological and topographical analysis. Our results indicate that the location and volume of the lesion were significantly associated with the clinical outcome and that mid-temperatures may be responsible for the lesion size. This could serve ultimately to improve targeting and judgment and to optimize clinical outcome of tcMRgFUS thalamotomy.
ABSTRACT
Background
Dopamine replacement therapy reduces most motor and nonmotor features of Parkinson's disease. However, with disease progression, adjustments of dopaminergics and the application ...of advanced therapies must be considered.
Objectives
To validate the OPTIMIPARK questionnaire as a tool to help clinicians make therapeutic decisions on patients treated with levodopa.
Methods
We tested a questionnaire including 9 items encompassing motor and nonmotor signs, complications, and disability in a multicenter, observational, cross‐sectional study. A neurologist (neurologist 1 N1) assessed patients according to regular clinical practice and blinded to the OPTIMIPARK questionnaire score. Therapeutic decisions were classified as “no changes,” “adjustment of conventional treatment,” and “advanced therapy indicated.” External neurologists (neurologist 3 N3 and neurologist 4 N4), who only knew the patient age, years of disease, and current treatment, made their therapeutic decisions based on the OPTIMIPARK score. Concordance between the criterion of the N1 versus the OPTIMIPARK‐based N3–N4 consensus was analyzed applying weighted κ. The area under Receiving Operating Characteristic (ROC) curves was calculated for OPTIMIPARK scores.
Results
A total of 113 patients with Parkinson's disease were included. The OPTIMIPARK‐based decision led to a higher proportion of patients requiring therapeutic modification than N1 assessment (74% vs. 60%; P = 0.002). Concordance between the N1 and N3–N4 decisions was moderate, whereas interobserver agreement among N3 and N4 was high. Area Under the Curve(AUC) values of 0.83 and 0.82 were found for “no changes” and “advanced therapy indicated” decisions by the N1 neurologist.
Conclusions
OPTIMIPARK might be more sensitive than regular clinical practice in suggesting the need for a therapeutic change. Furthermore, the low and high scores identify with high accuracy well‐adjusted patients and candidates for advanced therapy, respectively.
Impulse control disorders (ICDs) represent a side effect of dopaminergic medication in Parkinson's disease (PD). Patients experience an excessive desire toward natural rewards paired with ...uncontrolled actions. Yet, the precise neural and behavioral mechanisms associated with ICDs and, importantly, each specific subdomain remain unclear. We aim to decipher resting-state and corticolimbic functional connectivity in PD patients with and without hypersexual ICD.
Seventeen PD patients with hypersexuality (PD+HS) and 15 PD patients without hypersexuality (PD-HS) underwent two sessions (with and without medication) of resting-state functional magnetic resonance imaging and were compared with 17 healthy controls. Dual-regression independent component analyses extracted salience, sensorimotor, default-mode, and central executive networks. Seed-based functional connectivity with three striatal subdivisions (motor, associative, and limbic) was obtained and significant changes were correlated with key impulsivity and inhibitory measures.
Enhanced salience network (SN) activity represented by a significant rise in the right inferior frontal gyrus was found in PD+HS compared with PD-HS. Connectivity analyses revealed a functional disconnection between associative and limbic striatum with precuneus and superior parietal lobe in PD+HS, some connections explained by abnormal sexual behavior and inhibition in PD+HS.
Hypersexual ICD is associated with enhanced SN signaling and corticolimbic disconnections, including striatal associative and limbic loops that contribute to altered control of sexually driven behavior and overall severity in PD and ICD. Impact statement We enlarge the neurobiological basis to one specific Parkinson's disease (PD) and impulse control disorder (ICD) (PD+ICD) subtype-that is, hypersexuality-and reveal its associated resting-state functional connectivity linked to altered behavior. We report enhanced salience network and right inferior frontal gyrus as part of the underlying resting-state functional networks in PD patients with hypersexuality (PD+HS). Corticolimbic changes were associated with sexual severity in PD+HS to hypoactive connectivity between associative-limbic striatum with precuneus and superior parietal lobe. The connectivity changes seen in PD+HS could explain baseline differences that engender aberrant control over sexual behavior in ICD.