Visualization of Cerebral Arteries Using Contrast-Enhanced Transcranial Ultrasound in Stroke Patients

Visualization of Cerebral Arteries Using Contrast-Enhanced Transcranial Ultrasound in Stroke Patients

Visualization of the Cerebral Arterial Circulation Using Contrast-Enhanced Transcranial Ultrasound in Code Stroke Patients

The purpose of this study is to find out more about the usefulness of ultrasound in combination with a contrast solution to look for blood vessel blockage or occlusion in the brains of stroke patients.

Ischemic stroke is a common, devastating and costly disease. A stroke is usually caused by a blockage in one of the arteries that carries blood to the brain. The purpose of this study is to visualize the blood vessels in the brain and to look for vessel occlusion (i.e., blockage) which may be the cause of stroke. Ultrasound contrast imaging may or may not improve the ability to diagnose vessel occlusion in the brain quickly and precisely, thereby expediting the therapy currently in place for acute stroke. The contrast solutions used in this study have been approved by the Food and Drug Administration because they improve ultrasound pictures taken in the heart. While the solutions are approved for use with ultrasound in viewing the heart, the usefulness in viewing brain vessels has not been approved and is experimental. The study will enroll 400 participants with possible diagnosis of acute stroke. Individuals participating in the study will be injected with a contrast solution via an intravenous line. A small probe will be used to obtain images of blood vessels in the head. The study researchers will measure vital signs prior to injection of the contrast solution, 5 minutes after the injection, and at the end of the ultrasound. Each participant will have a 5-minute mental function assessment and a brief neurological exam. Participants will undergo at least 3 ultrasounds. The total time of each ultrasound is less than 30 minutes. This study is part of the Specialized Program of Translational Research in Acute Stroke to enhance and initiate translational research that ultimately will benefit stroke patients. Results from this study may help investigators learn about the future development of new diagnostic tests for stroke.

After written informed consent Code Stroke patients will undergo a contrast-enhanced transcranial ultrasound study to visualize the intracranial arteries. To do so, an ultrasound contrast agent (Definity) will be administered intravenously and transcranial ultrasound will be applied via the temporal bone window on both sides. Goal is to visualize and assess the intracranial arteries bilaterally. This includes the following vessel segments on both sides: middle cerebral artery (M1,M2,M3 segments), anterior cerebral artery (A1,A2 segments), posterior cerebral artery (P1,P2 segments), internal carotid artery (C1/2,C3/4 segments).

single intravenous administration of maximum 1.5 milliliter ultrasound contrast agent (Definity), followed by maximum 15 minutes transcranial insonation using diagnostic ultrasound.

Number of Participants With Successful Visualization of the Intracranial Arteries in Comparison to Reference Method (MRA/CTA)

The number of participants with successful visualization (yes/no) of the cerebral artery segments was assessed by an experienced sonographer who was blinded to the cerebral MRA/CTA.

Inclusion Criteria: patient 18 years of age or older code stroke patient Exclusion Criteria: women with positive pregnancy test women who are breast feeding severe emphysema pulmonary vasculitis history of pulmonary emboli chronic renal failure

Holscher T, Sattin JA, Raman R, Wilkening W, Fanale CV, Olson SE, Mattrey RF, Lyden PD. Real-time cerebral angiography: sensitivity of a new contrast-specific ultrasound technique. AJNR Am J Neuroradiol. 2007 Apr;28(4):635-9.