Patient description: A 62-year-old African-American man presented with left upper and lower extremity weakness, associated with dark visual spot in right eye, right facial numbness, facial drop and slurred speech. He denied dyspnea, headache, palpitations, chest pain, fever, dizziness, bowel or urinary incontinence, loss of consciousness. His medical history was significant for hypertension, hyperlipidemia and hypothyroidism. He smokes cigarette 1 pack per day for 40 years and alcohol consumption of 5 to 6 beers per week. He is not aware about his family history. He is using Levothyroxine, Atorvastatin and HTCZ. His vital signs were stable in the primary evaluation. Left-sided facial droop, dysarthria, and left-sided hemiplegia were seen in the physical exam. His National Institutes of Health Stroke Scale (NIHSS) score was calculated as 7. Initial CT angiogram of head and neck reported no acute intracranial findings. Intravenous recombinant tissue plasminogen activator (t-PA) was administered as well as high-dose statin therapy. The patient was admitted to the intensive care unit to be monitored for 24 hours. MRI of the head revealed an acute 1.7-cm infarct of the right periventricular white matter and posterior right basal ganglia.

Clinical trial eligibility criteria: eligible ages (years): 18.0-999.0,  Amyotrophic Lateral Sclerosis Diagnosed with laboratory supported probable, clinically probable or definite ALS according to the World Federation of Neurology Revised El Escorial (Brooks et al. 2000). 2. Right-hand dominant male or female aged 18 years or older. 3. Capable of providing informed consent and complying with study procedures, including tolerability in the supine position and MRI examination without significant claustrophobia. 4. If taking riluzole, on a stable dose for at least 30 days prior to Screening Visit. 5. Slow Vital Capacity equal to or more than 50% predicted value for gender, height and age in the 30 days prior to the Screening Visit and able to lie supine without BiPAP. 6. Severe left arm weakness and functional impairment, defined as Medical Research Council muscle strength score equals 3 or less in the index finger abduction and thumb abduction on the left side; OR severe left leg weakness and functional impairment, defined as Medical Research Council muscle strength score equals 3 or less at the hip flexors and ankle dorsiflexors on the left side. 7. Able to communicate during the ExAblate® MRI-guided FUS procedure  Unable to complete high-density CT and MRI studies of the head at the Screening Visit or any other MRI contraindication, such as Large body habitus and not fitting comfortably into the scanner Difficulty lying supine and still for up to 3 hours in the MRI unit or significant claustrophobia 2. MRI findings Active infection/inflammation Acute or chronic brain hemorrhages, specifically lobar or subcortical microbleeds, siderosis or macrohemorrhages Tumor/space occupying lesion Meningeal enhancement 3. More than 30% of the skull area traversed by the sonication pathway is covered by scars, scalp disorders (e.g., eczema), or atrophy of the scalp. 4. Clips or other metallic implanted objects in the skull or the brain, except shunts. 5. Significant cardiac disease or unstable hemodynamic status including Documented myocardial infarction within six months of enrollment Unstable angina on medication Unstable or worsening congestive heart failure