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clinical songraphy
ch. 5 definitions
Question | Answer |
---|---|
Acoustic Enhancement | because sound traveling through a fluid-like structure is barely attenuated, the structures distal to a cystic lesion appear to have more echoes than neighboring areas. Also referred to as "through transmission" |
Anechoic | without internal echoes. Not necessarily cystic unless there is distal echo enhancement. (black areas) |
Complex | a structure that has both fluid-filled (echo-free) and solid (echogenic) areas. |
Contralateral | On the other side of the body. |
Cyst | Spherical, fluid-filled structure with well defined walls that contains few or no internal echoes and exhibits good acoustic enhancements. |
Cystic | in ultra sonography, the word "cystic" does not necessarily refer to a cyst. the term is used (in accurately) by some to describe any fluid-filled structure (ex. urine-filled bladder or bile-filled gallbladder) |
Distal | the extremity (limb) end of a body structure. |
Echo-Free | Same as Anechoic |
Echogenic | Describes a structure that produces echoes. Usually a relative term. Ex. the normal texture of the liver and pancreas; the pancreas is slightly more echogenic. A change in the normal echogenicity signifies a pathologic condition. (bright white) |
Echogram | Term used by some to describe an ultrasonic examination, especially in cardiac work; an echocardiogram is frequently referred to as an "echo". |
Echolucent | Without internal echoes; not necessarily cystic. |
Echopenic | A few echoes within a structure; less echogenic. The normal kidney is echopenic relative to the liver. |
Echo-poor | Same as Echopenic |
Echo-rich | Same as Echogenic |
Fluid-Fluid Level | interface between two fluids with different acoustic characteristics. This interface has a horizontal level that varies with patient position. |
Footprint | Descriptive term for the amount of transducer face in contact with the patient (ex. a small-head transducer has a small footprint). |
Gain | the strength of the echoes throughout the image can be varied by changing the power output from the system. (echoes towards the transducer) |
Homogeneous | Of uniform composition. The normal texture of several parenchymal organs is homogeneous (ex. liver, thyroid and pancreas) |
Hyperchoic | Same as Echogenic |
Hypoechoic | same as Echopenic |
Interface | Strong echoes that delineate the boundary of organs and that are caused by the difference between the acoustic impedance of two adjacent structures. An interface is usually more pronounced when the transducer is perpendicular to it. |
Ipsilateral | On the same side of the body. |
Isoechoic | of the same echogenicity as a neighboring area, but necessarily of the texture. |
Noise | Artifactual echoes resulting from too much gain rather than from true anatomic structures. |
Proximal | the trunk end of a limb or organ. |
Reverberation | An artifact that results from a strong echo returning from a large acoustic interface to the transducer. This echo returns to the tissues again, causing additional echoes parallel to the first. |
Ring Down | Extreme form of reverberation artifact that occurs when a long series of echoes caused by a very strong acoustic interface and consequent reverberations are seen. |
Scan | Verb. to perform an ultrasound scan. Noun. a sonographic examination. |
Shadowing | failure of the sound beam to pass through an object. this blockage is caused by reflection or absorption of the sound and may be partial or complete. (Ex, air bubbles and calcified gallstones.) |
Solid (Homogeneous) | a mass or organ that contains uniform low-level echoes because the cellular tissues are acoustically very similar. |
Sonodense | structure that transmits sound poorly. dense structure can attenuate sound so greatly that the back wall is poorly defined. if very homogeneous, may be few/no internal echoes but the lack of acoustic enhancement & poor back wall help differentiate C & E-F |
Sonogenic | Handsome ultrasound image (photogenic) such as a good ex. of vascular anatomy. |
Sonographer | A health professional who has learned how to perform quality sonography and can tailor the examination to individual patients. |
Sonologist | A physician who specializes in ultrasonography and has appropriate training. |
Sonolucent (Anechoic) | Without echoes. Not necessarily cystic unless there is good through transmission. |
Specular Reflector | Structure that creates a strong echo because it interfaces at right angles to the sound beam and has significantly different acoustic impedance from a neighboring structure.(Ex. diaphragm/liver or posterior bladder wall/bladder) |
Static Scan | Not real time. B-scans produced with a fixed-arm system. Obsolete technique. |
Texture | the echo pattern within an organ; could be homogeneous or irregular. |
Through Transmission | the amount of sound passing through a structure. Same as acoustic enhancement. |
Transonicity | Term used to indicate the amount of sound passing through a mass or cyst, usually qualified as good or poor. Same as acoustic enhancement. |
Trendelenburg | a position in which a recumbent patient is tilted so that the feet are higher than the head. |