Search results
Results from the WOW.Com Content Network
The ultrasound equipment must be sufficiently high-quality to give a correct image-processing result, which can then provide invaluable information, mainly at the superficial level. It must be able to provide both color and Doppler imaging, technologies that developed alongside the development of ultrasound. Doppler measurements which trace the ...
T 2 *-weighted sequences are used to detect deoxygenated hemoglobin, methemoglobin, or hemosiderin in lesions and tissues. [2] Diseases with such patterns include intracranial hemorrhage, arteriovenous malformation, cavernoma, hemorrhage in a tumor, punctate hemorrhages in diffuse axonal injury, superficial siderosis, thrombosed aneurysm, phleboliths in vascular lesions, and some forms of ...
Medical ultrasound includes diagnostic techniques (mainly imaging techniques) using ultrasound, as well as therapeutic applications of ultrasound. In diagnosis, it is used to create an image of internal body structures such as tendons, muscles, joints, blood vessels, and internal organs, to measure some characteristics (e.g., distances and velocities) or to generate an informative audible sound.
These procedures generally use lower frequencies than medical diagnostic ultrasound (from 0.7 to 2 MHz), but higher the frequency means lower the focusing energy. HIFU treatment is often guided by MRI. Focused ultrasound may be used to dissolve kidney stones by lithotripsy. Ultrasound may be used for cataract treatment by phacoemulsification.
The sign is an imaging finding using a 3.5–7.5 MHz ultrasound probe in the fourth and fifth intercostal spaces in the anterior clavicular line using the M-Mode of the machine. This finding is seen in the M-mode tracing as pleura and lung being indistinguishable as linear hyperechogenic lines and is fairly reliable for diagnosis of a pneumothorax.
Ultrasound can ablate tumors or other tissue non-invasively. [4] This is accomplished using a technique known as high intensity focused ultrasound (HIFU), also called focused ultrasound surgery. This procedure uses generally lower frequencies than medical diagnostic ultrasound (250–2000 kHz), but significantly higher time-averaged intensities.
By changing the pulse delays, the computer can scan the beam of ultrasound in a raster pattern across the tissue. Echoes reflected by different density tissue, received by the transducers, build up an image of the underlying structures. Weld examination by phased array. TOP: The phased array probe emits a series of beams to flood the weld with ...
The transducer may be used in contact with the skin, as in fetal ultrasound imaging, or inserted into a body opening such as the rectum or vagina. Clinicians who perform ultrasound-guided procedures often use a probe positioning system to hold the ultrasonic transducer. [9] Compared to other medical imaging modalities, ultrasound has several ...