A rotating impeller in a rotary blood pump requires a supporting system in blood, such as a pivot bearing or magnetic suspension. To solve potential problems such as abrasive wear and complexity of a supporting system, a magnetic fluid seal was developed for use in an axial-flow blood pump. Sealing pressures at motor speeds of up to 8,000 rpm were measured with the seal immersed in water or bovine blood. The sealing pressure was about 200 mm Hg in water and blood. The calculated theoretical sealing pressure was about 230 mm Hg. The seal remained perfect for 743 days in a static condition and for 180+ days (ongoing test) at a motor speed of 7,000 rpm. Results of measurement of cell growth activity indicated that the magnetic fluid has no negative cytological effects. The specially designed magnetic fluid shaft seal is useful for an axial-flow blood pump.
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http://dx.doi.org/10.1046/j.1525-1594.2003.00035.x | DOI Listing |
Neurooncol Adv
December 2024
Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.
Background: Intrathecal (IT) chemotherapy is essential in treating hematological malignancies, but it can lead to ascending paraplegia, a condition that currently lacks clear management guidelines.
Methods: We conducted a systematic review, analyzing 1219 studies and 116 patients, adhering to PRISMA guidelines for individual patient data. The study, registered under PROSPERO (CRD42022362121), focused on the onset, diagnostic approaches, and therapeutic interventions associated with this complication, and management strategies to tackle the ascending paraplegia.
Eur J Case Rep Intern Med
December 2024
Department of Geriatrics and Internal Medicine, Champmaillot Hospital, University Hospital, Dijon, France.
Introduction: According to the World Health Organization, 44 million people worldwide suffer from Alzheimer's disease. Abnormal movements are atypical symptoms of Alzheimer's disease.
Case Description: An 87-year-old woman, followed for Alzheimer's disease, experienced abnormal movements.
Cardiovasc Diagn Ther
December 2024
Department of Heart, Vascular & Thoracic, Division of Cardiology & Cardiovascular Medicine - Pediatric Cardiology, Cleveland Clinic Lerner College of Medicine, Cleveland, OH, USA.
As the population of adults with congenital heart disease (ACHD) grows, there also grows an expanded need for non-invasive surveillance methods to guide management and intervention. A multimodal imaging approach layers complementary insights from echocardiography, computed tomography (CT), magnetic resonance imaging (MRI), and other modalities into a clinician's view of patient physiology. Merely applying strategies from acquired adult cardiac disease would be inadequate and potentially misleading.
View Article and Find Full Text PDFCardiovasc Diagn Ther
December 2024
Cardiovascular Center, St. Luke's International Hospital, Tokyo, Japan.
Right ventricular (RV) dysfunction after biventricular repair is critical in most adults with congenital heart disease (ACHD). Conventional 2D magnetic resonance imaging (MRI) measurement is considered as a 'gold standard' for RV evaluation; however, addition information on ACHD after biventricular repair is sometimes required. The reasons why adjunctive information is required is as follows: (I) to evaluate the severity of cardiac burden in symptomatic patients with normal RV size and ejection fraction (EF), (II) to determine the optimal timing of invasive treatments in asymptomatic ones, and (III) to detect proactively a potential cardiac burden leading to ventricular deterioration, from a fluid dynamics perspective.
View Article and Find Full Text PDFJ Surg Case Rep
January 2025
Department of Neurological Surgery, Nippon Medical School Hospital, Tokyo, Japan.
We report a case of distal anterior cerebral artery (DACA) aneurysm presenting with subdural hematoma (SDH) without subarachnoid hemorrhage (SAH). A patient in his fifties presented with headache. Fluid-attenuated inversion recovery magnetic resonance imaging revealed SDH in the interhemispheric fissure and left frontotemporal region.
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