1 / 15

Unidad 8 Biofísica sensorial

Unidad 8 Biofísica sensorial. Dr. Juan José Aranda Aboy Profesor e Investigador Titular. Contenido y Objetivos. Luz y Visión Fuentes luminosas. Receptores luminosos. Agudeza visual. Sonido Intensidad y Decibeles. Oído externo, medio e interno. Fenómenos de transducción.

chaney-nichols
Download Presentation

Unidad 8 Biofísica sensorial

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Unidad 8Biofísica sensorial Dr. Juan José Aranda Aboy Profesor e Investigador Titular

  2. Contenido y Objetivos • Luz y Visión • Fuentes luminosas. Receptores luminosos. • Agudeza visual. • Sonido • Intensidad y Decibeles. • Oído externo, medio e interno. Fenómenos de transducción. • Caracterizar y explicar los elementos que integran los sistemas de percepción visual y auditiva de los seres humanos.

  3. Different types of ultrasonic transducers range in frequency from 12 MHz for ophthalmic devices to 4 MHz for transducers equipped with a spinning head.

  4. Ultrasound scan heads Transducers • Rotating mechanical device. • Linear phased array which scans an area of the same width as the scan head. • Curved linear array can sweep a sector. • Phasing the excitation of the crystals can steer the beam so that a small transducer can sweep a large area. Beam axis Beam axis Direction of sweep Direction of sweep (a) (b) Pulses to individual elements Beam axis Direction of sweep Direction of sweep (c) (d)

  5. B-mode ultrasonic imaging shows the two-dimensional shape and reflectivity of objects by using multiple-scan paths.This B-mode ultrasonic image, which corresponds to (a), shows the skin of the belly at the top right, the liver at the left center, the gall bladder at the right above center, and the kidney at the right below center. The bright areas within the kidney are the collecting ducts.

  6. Simultaneous recording of motion mode (M-mode) and two dimensional echocardiograms. The arrows on the right image indicates the position of the ultrasound beam from which the M-mode recording was made. LVW = left ventricular wall, LV = left ventricle, LA = left atrium, RV = right ventricle. From College of Veterinary Medicine, Univ. of Tennessee. 2000. M-Mode Echocardiography [Online] http://www.vet.utk.edu/m-mode.html

  7. Intravascular ultrasonic image showing the characteristic three-layer appearance of a normal artery. Mild plaque and calcification can be observed at 7 o'clock.

  8. Sector-scan limits Doppler sample volume The duplex scanner contains a mechanical real-time sector scanner that generates a fan-shaped two-dimensional pulse-echo image. Signals from a selected range along a selected path are processed by pulsed Doppler electronics to yield blood velocity. Real-time pulse-echo imaging electronics From pulse-echo imaging transducer Motor housing and handle Display Servo-controlled motor From pulsed-doppler transducer Flexible bellows drive Pulsed- To and from servo- controlled motor doppler Imaging transducer electronics Acoustic window Motor servo- control electronics Video overlay electronics B Pulsed-doppler beam Doppler sample volume Doppler-beam positional data Limits of real-time pulse-echo sector scan

  9. Duplex scanner B-mode image and Doppler spectral analysis record for a normal carotid artery, near the bifurcation. The Doppler signals were recorded from the sample volume defined by the Doppler cursor, the two parallel lines located inside the carotid artery.(b) Color flow image of the vessel in (a). Higher velocity components (light color, reproduced here in black and white) are seen where the vessel direction courses more directly toward the transducer.

  10. Imágenes • ultrasound.avi (CD – Web Imágenes) • Ejecutar programa dearrollado en MatLab 6.5: JJDicom.m (CD – Web Imágenes \ work \ Anita )

  11. REFERENCIAS BIBLIOGRÁFICAS • Bronzino, et. al. BME Handbook Ch04, “Vision System” y Ch05 Auditory System” • Davidovits,P. “Physics in Biology and Medicine” 2nd Ed. Academic Press, 2001 (ISBN 0-12-204840-7) Caps. 12, pp 151-167; y 15, pp 200-222 • Frumento S.A. “Biofísica” 3ra edición. Ed. Mosby / Doyma Libros, 1995, (ISBN 84-8174-073-X) Caps. 20 al 23, pp 373-448 • Jou,D.; Llebot,J.E. y Pérez García,C. “Física para Ciencias de la Vida” McGrawHill / Interamericana, 1994 (ISBN 84-481-1817-0) Caps. 5, pp 229-310; y 7, pp 381-486 • Parisi,M. “Temas de Biofísica”. McGrawHill /Interamericana, 2001 (ISBN 956-278-144-5) Cap. 6, pp 107-132

More Related