RESUMO
Stasis thrombi, radiolabeled with Tc-99m sulfur colloid, were produced in six dogs by the injection of human thrombin into isolated jugular vein segments. After release of the thrombi, scintigraphic images demonstrated 16 pulmonary emboli containing Tc-99m. Autologous platelets labeled by the In-111 oxine method were injected. Sequential images demonstrated platelet accumulation in 14 of the 16 emboli within 1 hr. The emboli were recovered at autopsy and their activity assayed. The mean uptake of In-111-labeled platelets was 1.1% dose/g of embolus, and the mean embolus-to-blood ratio was 16. Our results demonstrate that fresh pulmonary emboli in dogs can be detected by imaging with In-111-labeled platelets, and suggest that radiolabeled platelets may provide a simple, noninvasive method for the direct visualization of pulmonary emboli in patients.
Assuntos
Plaquetas , Índio , Embolia Pulmonar/diagnóstico , Cintilografia , Animais , Cães , Feminino , RadioisótoposRESUMO
An in-vitro study has been made of the echo patterns obtained during ultrasonic Time-Motion (T-M) scanning of commonly used prosthetic heart valves. Studies have been undertaken of Starr-Edwards, Beal, and Björk-Shilley valves. From the recorded traces information has been obtained regarding the orientations of the ultrasound beam to the central axes of the valves for which accurate measurements can be made. The orientations have been determined for which the opening and closing times of the valves can be measured to within 20 ms. Characteristics of the T-M trances have been noted which allow the angle between the direction of an ultrasound beam and a central valve axis to be reduced to less than 20 degrees. This makes the error due to angular misalignment of the beam less than --6% when the range of movement of a ball, disc, or flap is being measured. Finally a number of artefacts are considered which can arise when prosthetic valves are examined with ultrasound.
Assuntos
Próteses Valvulares Cardíacas , Ultrassonografia , Movimento (Física) , Fatores de TempoRESUMO
A patient with a massive false aneurysm of the left ventricle following myocardial infarction is described. The pseudoaneurysm compressed the esophagus causing severe dysphagia, and contributed to advanced terminal cachexia.
Assuntos
Transtornos de Deglutição/etiologia , Aneurisma Cardíaco/complicações , Ventrículos do Coração , Autopsia , Caquexia/etiologia , Cardiomegalia/diagnóstico , Complicações do Diabetes , Diagnóstico Diferencial , Eletrocardiografia , Aneurisma Cardíaco/diagnóstico , Aneurisma Cardíaco/etiologia , Aneurisma Cardíaco/patologia , Humanos , Índio , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Cintilografia , FumarRESUMO
The technique of radiographic examination by lymphography of normal lymphatic structures regional to the hind limbs is described in the rabbit, dog and rhesus monkey. Radiographic appearances of normal lymph nodes and possible applications to veterinary science are indicated.Normal lymph node microstructure is illustrated using in vivo intralymphatic injection of a brightly colored radiopaque silicone rubber. Angiogenesis in active germinal follicles during the period of an immune response is displayed. Further applications of the casting technique are suggested.