5 Clinical Trials for Various Conditions
Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure leading to symptoms like papilledema, headache, and cognitive dysfunction. While the etiology is complex, abnormal cerebrospinal fluid dynamics due to venous outflow restriction from transverse sinus stenosis (TSS) is common. TSS may disrupt the glymphatic system, a brain-wide network facilitating cerebrospinal fluid and interstitial fluid exchange, by impairing CSF absorption, altering perivascular space dynamics, and disrupting pressure gradients crucial for waste clearance. Venous sinus stenting (VSS) can improve symptoms in many patients by alleviating venous congestion, but its effects on glymphatic function are unclear. This prospective study aims to evaluate novel quantitative brain imaging metrics as surrogate markers to better understand IIH pathophysiology before and after VSS in patients with refractory IIH and TSS. The investigators will use advanced MRI techniques, including MR elastography (MRE) to assess brain stiffness, diffusion tensor imaging (DTI) to evaluate water diffusion, arterial spin labeling (ASL) imaging to measure blood-brain barrier (BBB) permeability, and functional MRI to analyze pain networks. The investigators hypothesize that 1) these noninvasive imaging metrics will correlate with the degree of venous congestion and changes after venous sinus stenting (VSS) and 2) the imaging findings will correlate with clinical treatment outcomes. By correlating imaging markers with venous pressures and symptom changes, the investigators aim to gain insights into IIH mechanisms, expand diagnostic tools, and potentially guide clinical decision-making and treatment response monitoring. The overarching goal is to better understand IIH's underlying pathophysiology, which could lead to improved diagnostic criteria, more targeted treatments, and better prediction of treatment outcomes for patients with this challenging condition.
This study is designed to measure the change in patients diagnosed with Parkinson's disease (PD) before, during and after a 12 week exercise program.The focus of this study is the glymphatic system. The glymphatic system is a recentlydiscovered novel waste clearance pathway, in patients with Parkinson's Disease (PD).The glymphatic system acts as a waste-clearance system in the brain of vertebrate animals.The glymphatic system has been proposed in which new clearance pathways involving communication between paravascular spaces, interstitial fluid, and ultimately meningeal and dural lymphatic vessels exists, and we have provided evidence that this system may be dysfunctional in patients with Parkinson's disease with cognitive disorders. Early research suggest glymphatic function increases following exercise, this response is believed to clear beta-amyloid in the brain and may mediate the neurobehavioral response to exercise in PD. This study will use cognitive exams, neurological exams as well as specialized imaging to record data points and evaluate the glymphatic function after exercise.
This involves development and application of magnetic resonance imaging (MRI) methods for visualizing hemodynamic and metabolic relationships in healthy volunteers with advanced meditation experience.
Background: Brain activity creates waste products. The body s glymphatic system removes this waste, especially during sleep. One brain waste product is amyloid-beta (Ab). It plays a role in Alzheimer s disease. Researchers want to study the effect of sleep on Ab in the brain. Objective: To see if sleep affects the amount of waste product removed from the brain. Eligibility: Healthy people at least 18 years of age. Design: Participants will be screened with a medical history, physical exam, and blood and urine tests. They will answer questions about drug use, psychiatric history, and family history of alcoholism or drug use. Participants will complete an MRI screening questionnaire. Participants will stay in the clinic overnight two times. On one night they will sleep through the night. On the other night they will be kept awake all night. These overnight visits can happen in any order. Participants will wear 2 activity monitors, on the wrist and the ankle. Participants will have positron emission tomography (PET) scans. A small amount of a radioactive chemical will be injected through an intravenous (IV) catheter. Participants will lie on a bed that slides into the scanner. A cap or a special mask may be placed on the participant s head. Participants will have magnetic resonance imaging (MRI) scans. The MRI scanner is a metal cylinder in a strong magnetic field. Participants will lie on a table that slides into the cylinder. A device called a coil will be placed over the head. Participants will do a task on a computer screen in the scanner. Participants will have tests of thinking, memory, and attention. They may be interviewed, complete questionnaires, take pen-and-paper or computer tests, and perform simple actions.
This study is being done in order to see how gadolinium-based MRI contrast (Magnevist) travels through the central nervous system (CNS) when injected through the spinal column, and to compare differences between two age groups (age 20-50, and 51-80). This will allow investigators to evaluate how much contrast has crossed into the tissue surrounding the brain. Such information will help investigators determine whether this kind of contrast can be used to model how other drugs might travel through the CNS and evaluate its use as an illustrative imaging marker that mirrors the glymphatic system.