Skull Density Ratio as Arm-Allocation Parameter for a Controlled Focused Ultrasound Trial in Parkinson's Disease.

Background: MR-guided focused ultrasound (FUS) thermoablation is an established therapy for movement disorders. FUS candidates must meet a predefined threshold of skull density ratio (SDR), a parameter that accounts for the efficiency in reaching ablative temperatures. Randomized sham-controlled trials to provide definitive therapeutic evidence employ pure randomization of subjects into active treatment or control arms.

Staged Bilateral MRI-Guided Focused Ultrasound Subthalamotomy for Parkinson Disease.

Importance: Unilateral magnetic resonance imaging (MRI)-guided focused ultrasound subthalamotomy (FUS-STN) improves cardinal motor features among patients with asymmetrical Parkinson disease (PD). The feasibility of bilateral FUS-STN is as yet unexplored.

Objective: To assess the safety and effectiveness of staged bilateral FUS-STN to treat PD.

Brain hypometabolism in non-demented microtubule-associated protein tau H1 carriers with Parkinson's disease.

Background And Purpose: The microtubule-associated protein tau (MAPT) H1 homozygosity (H1/H1 haplotype) is a genetic risk factor for neurodegenerative diseases, such as Parkinson's disease (PD). MAPT H1 homozygosity has been associated with conversion to PD; however, results are conflicting since some studies did not find a strong influence. Cortical hypometabolism is associated with cognitive impairment in PD.

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).

BBB opening with focused ultrasound in nonhuman primates and Parkinson's disease patients: Targeted AAV vector delivery and PET imaging.

Intracerebral vector delivery in nonhuman primates has been a major challenge. We report successful blood-brain barrier opening and focal delivery of adeno-associated virus serotype 9 vectors into brain regions involved in Parkinson's disease using low-intensity focus ultrasound in adult macaque monkeys. Openings were well tolerated with generally no associated abnormal magnetic resonance imaging signals.

Striatal Blood-Brain Barrier Opening in Parkinson's Disease Dementia: A Pilot Exploratory Study.

Background: Parkinson's disease (PD) exhibits a high prevalence of dementia as disease severity and duration progress. Focused ultrasound (FUS) has been applied for transient blood-brain barrier (BBB) opening of cortical regions in neurodegenerative disorders. The striatum is a primary target for delivery of putative therapeutic agents in PD.

Neuroimaging signatures predicting motor improvement to focused ultrasound subthalamotomy in Parkinson's disease.

Subthalamotomy using transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) is a novel and promising treatment for Parkinson's Disease (PD). In this study, we investigate if baseline brain imaging features can be early predictors of tcMRgFUS-subthalamotomy efficacy, as well as which are the post-treatment brain changes associated with the clinical outcomes. Towards this aim, functional and structural neuroimaging and extensive clinical data from thirty-five PD patients enrolled in a double-blind tcMRgFUS-subthalamotomy clinical trial were analyzed.

Lesion 3D modeling in transcranial MR-guided focused ultrasound thalamotomy.

Transcranial magnetic resonance-guided focused ultrasound (tMRgFUS) allows to perform incisionless thermoablation of deep brain structures. This feature makes it a very useful tool for the treatment of multiple neurological and psychiatric disorders. Currently, feedback of the thermoablation process is based on peak temperature readings assessed on real-time two-dimensional MRI thermometry.

Present and future of subthalamotomy in the management of Parkinson´s disease: a systematic review.

The subthalamic nucleus (STN) is known to be involved in the pathophysiology of Parkinson´s disease and by reducing its abnormal activity, normal output of basal ganglia can be restored along with improvement in PD cardinal motor features. Deep brain stimulation of the STN is currently the main surgical procedure for PD with motor complications, but lesioning can be an alternative. Here, the authors systematically review the current evidence regarding subthalamotomy both with radiofrequency and, more recently, with focused ultrasound (FUS) for the treatment of PD.

Randomized Trial of Focused Ultrasound Subthalamotomy for Parkinson's Disease.

Background: 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.

Methods: 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.

An application of generalized matrix learning vector quantization in neuroimaging.

Background And Objective: Neurodegenerative diseases like Parkinson's disease often take several years before they can be diagnosed reliably based on clinical grounds. Imaging techniques such as MRI are used to detect anatomical (structural) pathological changes. However, these kinds of changes are usually seen only late in the development.

Partial recovery of vegetative state after a massive ischaemic stroke in a child with sickle cell anaemia.

A 15-year-old patient with sickle cell disease with recessive homozygous haemoglobin S/HbSS suffered several crises developmentally after the last of which the patient fell into coma. CT scan then revealed a large infarct of the right cerebral hemisphere. Three weeks after the event, the patient began to demonstrate spontaneous eye opening and spastic quadriparesis with no evidence of command-following, gestural or verbal communication, visual pursuit or purposeful motor behaviour.

Functional impact of subthalamotomy by magnetic resonance-guided focused ultrasound in Parkinson's disease: a hybrid PET/MR study of resting-state brain metabolism.

Purpose: Subthalamotomy using magnetic resonance-guided focused ultrasound (MRgFUS) has become a potential treatment option for the cardinal features of Parkinson's disease (PD). The purpose of this study was to evaluate the effects of MRgFUS-subthalamotomy on brain metabolism using different scale levels.

Methods: We studied resting-state glucose metabolism in eight PD patients before and after unilateral MRgFUS-subthalamotomy using hybrid [F]FDG-PET/MR imaging.

Transcranial Magnetic Resonance-Guided Focused Ultrasound Thalamotomy in Essential Tremor: A Comprehensive Lesion Characterization.

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.

Focused ultrasound in Parkinson's disease: A twofold path toward disease modification.

A major unmet need in Parkinson's disease (PD) is to slow the inexorable progression of neurodegeneration. Clinical trials that evaluated promising pharmacological strategies have repeatedly failed. Nonetheless, the advent of focused ultrasound provides new opportunities toward the goal of developing a safe and effective disease-modifying therapy for PD.

Zero TE MRI applications to transcranial MR-guided focused ultrasound: Patient screening and treatment efficiency estimation.

Background: The high acoustic impedance of the skull limits the performance of transcranial magnetic resonance-guided focused ultrasound (tcMRgFUS) therapy. Subject suitability screening is based on skull parameters estimated from computed tomography (CT) scans.

Purpose: To assess the feasibility of screening for tcMRgFUS based on zero echo time (ZTE) MRI, and to explore the influence of measurable skull parameters in treatment performance.