RESUMO
Abnormal blood flow and wall shear stress (WSS) can cause and be caused by cardiovascular disease. To date, however, no standard method has been established for mapping WSS in vivo. Here we demonstrate wide-field assessment of WSS in the rabbit abdominal aorta using contrast-enhanced ultrasound image velocimetry (UIV). Flow and WSS measurements were made independent of beam angle, curvature or branching. Measurements were validated in an in silico model of the rabbit thoracic aorta with moving walls and pulsatile flow. Mean errors over a cardiac cycle for velocity and WSS were 0.34 and 1.69%, respectively. In vivo time average WSS in a straight segment of the suprarenal aorta correlated highly with simulations (PC = 0.99) with a mean deviation of 0.29 Pa or 5.16%. To assess fundamental plausibility of the measurement, UIV WSS was compared to an analytic approximation derived from the Poiseuille equation; the discrepancy was 17%. Mapping of WSS was also demonstrated in regions of arterial branching. High time average WSS (TAWSSxz = 3.4 Pa) and oscillatory flow (OSIxz = 0.3) were observed near the origin of conduit arteries. In conclusion, we have demonstrated that contrast-enhanced UIV is capable of measuring spatiotemporal variation in flow velocity, arterial wall location and hence WSS in vivo with high accuracy over a large field of view.
Assuntos
Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/fisiologia , Animais , Artéria Celíaca/diagnóstico por imagem , Artéria Celíaca/fisiologia , Meios de Contraste/farmacologia , Hemodinâmica , Coelhos , Artéria Renal/diagnóstico por imagem , Artéria Renal/fisiologia , Reologia , Estresse Mecânico , UltrassonografiaRESUMO
Evelyn K. Oremland, Ph.D., founded the first college-based Child Life Program on the West Coast. A pioneer in child life, in her twenty years at Mills College, Oakland, California, she developed a graduate curriculum to create the child life profession. Through her tireless activities in the international organization, Association for the Care of Children's Health (ACCH), and her co-chairing the Educational Committee of the Child Life Council, she helped establish standards for the child life specialist certification. Around the world, her teaching, research, and writing have helped protect the emotional development of sick children. She is best remembered as a devoted and beloved teacher. Graduates from her program now occupy many senior administrative positions in child life in the United States and in Europe.
Assuntos
Criança Hospitalizada/história , Ludoterapia/história , Criança , História do Século XX , Humanos , Estados UnidosAssuntos
Carcinoma/patologia , Neoplasias da Coroide/patologia , Carcinoma/complicações , Carcinoma/tratamento farmacológico , Corioide/patologia , Neoplasias da Coroide/complicações , Neoplasias da Coroide/tratamento farmacológico , Oftalmopatias/etiologia , Oftalmopatias/patologia , Humanos , Neoplasias Pulmonares , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prednisona/uso terapêutico , Descolamento Retiniano/etiologia , Descolamento Retiniano/patologia , Úvea/patologiaRESUMO
In the light of three case reports, the authors explain the symptoms of the maxillonasal syndrome and draw conclusions as to orthodontic therapy.
Assuntos
Disostose Craniofacial , Desenvolvimento Maxilofacial , Adolescente , Criança , Face , Feminino , Seio Frontal/anormalidades , Humanos , Masculino , Má Oclusão/terapia , Ortodontia CorretivaRESUMO
Splenic trauma is a rare complication of colonoscopy and is often not readily diagnosed. A computerized tomographic scan enabled us to diagnose splenic trauma without hematoperitoneum in a patient presenting with abdominal and left shoulder pain 10 days post-colonoscopy. The scan information and the patient's clinical status allowed for nonoperative treatment of the injury.