Ch.4 (pg.26-28) Terms (Curry) Flashcards
AL ARA (as low as reasonably achievable)
The prudent use of diagnostic sonography; dictates that the output level and exposure time to ultrasound is minimize while obtaining diagnostic data.
Example: always consider AL ARA when scanning. The thermal index (TI) and mechanical index (MI) are components of the ultrasound bioeffects that should be monitored while scanning. The TI and MI values are usually located in the upper right side of the display screen.
Interior (ventral)
Situated at or directed toward the front. A structure in front of another structure.
Example: the liver is situated anteriorly in the body. The body of the pancreas is anterior to portions of the: splenic vein; superior mesenteric artery; Left renal vein; abdominal aorta; spine. The head of the pancreas is anterior to the inferior vena cava.
Acoustic impedance
Resistance a material provides to the passage of soundwaves.
Example: bone portrays more acoustic impedance than tissue.
Acoustic shadows
“Reduced echo amplitude” or I can “drop off” posterior to a structure that attenuated (decreases, stop, impedes, or absorbs) the sound beam. Margins of the shadow are generally sharp and well defined. Considered a type of sonographic artifacts.
Example: black posterior shadowing can be visualized posterior to the fetal femur.
Anechoic
Term used to describe an echo-free appearance on a sonographic image.
Example: a true cyst appears anechoic.
Artifact
Image artifacts are echo features or structures observed on ultrasound images that are on associated with the object being imaged.
Example: acoustic shadows are one type of sonographic artifact.
Ascites
Accumulation of serious fluid anywhere in the abdominopelvic cavity.
Example: ascites may be visualized in the posterior cul-de-sac of the Abdominopelvic cavity.
Attenuation
Decrease in the intensity of the sound beam as it passes through a structure, caused by absorption, scatter, or beam divergence.
Example: the density, composition, and angle of the sound beam when it strikes an object determine how much of the sound beam is attenuated.
Axial (short axis) (view or section)
At right angles to longitudinal sections.
Example: axial views of the aorta maybe seen in transverse scanning plane images. Axial sections of the pancreas can be visualized in sagittal scanning plane images of the mid hypogastrium.
Beam divergence
Widening of the sound beam as it travels.
Example:The pyramid appearance of an ultrasound image typifies beam divergence.
Calculi/”stones”
Concentration of mineral salts that may accompany some disease processes.
Example:Calculi are often visualized within the gallbladder as bright, movable, structures that vary in size and cask posterior shadows.
Calipers (Electronic)
Two or more measurement pursers that can be manipulated to calibrate the distance between echoes of interest on the imaging screen.
Example: measurement calipers are used to obtain length, width, and interest to posterior measurements to provide the dimensions or total volume of a structure of interest.
Color flow Doppler
Doppler shift information into a two dimensional presentation super imposed on a real-time gray scale anatomic cross-sectional images.
Example: flow directions are presented as different colors on the ultrasound display screen.
Complex mass
Abnormal mass within the body composed of both tissue and fluid.
Example: a complex mass is classified as an abnormal tissue and fluid collection within the body that disrupts the otherwise normal echo pattern of an organ parenchyma.
Acoustic enhancement
Increased echo amplitude or through transmission visualized posterior to a structure that does not attenuate (decrease stop impede or absorb)The sound beam.considered a type of sonographic artifact.
Example: Bright posterior through transmission can be visualized posterior to the urinary bladder
Contralateral
Situated on or affecting the opposite side.
Example: the ovaries are contralateral organs.
Contrast
A comparison to show differences.
Example: an ultrasound image produces a preponderance of dark and light comparative grayscale tones.
Coronal scanning planes
Any plane parallel to the long axis of the body and perpendicular to transverse scanning planes.
Example: a coronal scanning plane image demonstrate the anatomy visualized in a lateral to medial dimension and superior to inferior dimension.
Coupling agent
Substance used to reduce air between the ultrasound transducer and surface of the skin.
Example: gel is a typical coupling agent used in sonography.
Crura of diaphragm
Right and left crus or fibromuscular bands arising from the lumbar vertebrae that insert into the central tendon of the diaphragm.
Example: the Crura of the diaphragm are often visualized on ultrasound images as curvilinear structures immediately adjacent to the spine. Their sonographic appearance varies from Bright to hypoechoic relative to adjacent structures.
Cystic
Describes the sonographic appearance of a fluid collection within the body that does not meet the criteria to be considered a true cyst.
Example: ascites is said to be cystic in nature.
Deep
Internal. Situated away from the surface.
Example: the kidneys are deep structures within the body.
Depth of penetration
Maximum distance the sound beam travels from the transducer through a medium.
Example: the greater the intensity of the ultrasound beam, the greater the distance the beam will travel through a medium.The greater the attenuation of a medium, the less the distance of the travel.
Diffuse disease
Infiltrative disease throughout an organ that disrupts the otherwise normal sonographic appearance of Organ parenchyma.
Example: Infiltrative disease alters the normal echo pattern and throughout and Oregon.
Distal
Situated farthest from the point of origin.
Example: the abdominal aorta is distal to the thoracic aorta.
Doppler (effect)
Change and other sound frequency caused by relative motion between the source of the sound or reflector and the observer.
Example: Doppler is used to detect bloodflow through vessels. It detects not only the presence of flow but also the direction of flow by measuring the difference in the frequency of the reflected sound compared with the transmitted sound.
Echogenic
Describe the structure that is able to produce echoes or echo pattern. Hyperechoic, hypoechoic, and anechoic are the terms used to quantify either abundance or absence of echoes displayed by a structure in a sonographic image.
Example: body structures are echogenic or capable of producing echoes.
Echopenic
few echoes.
Example: The bile gallbladder may appear echopenic
Echo texture
Describes the sonographic appearance of soft tissue in the body.
Example: normal organ parenchyma (soft tissue) is characterized sonographically as homogeneous or uniform in echotexture. If disrupted or changed by disease, the parenchyma typically assumes an irregular or heterogenous Echotexture or pattern. The nature of this change may be diffuse disease (infiltrative; focal) or localized disease (a mass or multiple masses circumscribed to a specific area).
Extraorgan pathology
Abnormal disease process that originates outside of an organ.
Example: an extra hepatic mass may be visualized originating outside of an organ causing abnormalities such as displacement of other organs and structures, obstruction of other organs or structures from view, internal invagination of organ capsules, and discontinuity of organ capsules.
Focal/multifocal change
Disease process confined to isolated areas of an organ.
Example: a focal area of altered echo pattern may be visualized in only a part of an organ.
Focal zone
The point at which the sound beam is the narrowest and the resolution is the best.
Example: different transducers have different depths where their focus or focal zone is optimal. Therefore, the depth of a structure (of interest) within the body determines which transducer should be used.