The accurate description and interpretation of sonograms depends on the correct use of related terms associated with the reflection and attenuation characteristics of structures. Masses are categorized a solid, cystic, or complex depending on the observed sonographic characteristics. Enhancement, shadowing, and speckle are also discussed in Module 4 under Artifacts.
Terms Related To Echogenicity
Structures with acoustic interfaces show different degrees of reflectivity which translates into different levels of echogenicity in the sonogram.
Echogenic: a region in an ultrasound image which has echoes. Synonymous terms: reflective, echo-producing, echoic.
Anechoic: literally means “without echoes”. An anechoic region in an ultrasound image contains no echoes. Synonymous term: echo-free. Another term that is erroneously used is “echolucent”. This term has come from Radiology where the term radiolucent is used to describe dark-appearing areas on a radiograph representing tissues that permit passage of x-rays. Use the term anechoic rather than the term echolucent.
“Transonic” is not a synonymous term although sometimes it is inappropriately used to mean anechoic. Transonic describes an area of relatively low attenuation. As an example, the normal gallbladder is transonic therefore acoustic enhancement is seen distal to it. If the gallbladder contains 'sludge' (echogenic bile) it has real echoes in it (it is no longer anechoic) but it remains transonic relative to soft tissue and still produces acoustic enhancement. See atlas figures 1-8A and 1-9.
Hyperechoic: in an ultrasound image, describes a structure which has many echoes. Synonymous term: hyperechogenic. See atlas figure 1-10.
Hypoechoic: in an ultrasound image, describes a structure which has few echoes. Synonymous terms: echo poor, echopenic. See atlas figure 1-11.
Isoechoic: having the same echo density or brightness as another structure. As an example, the pancreas may be isoechoic to the liver. See atlas figure 1-12. If a solid
lesion is isoechoic to the surrounding parenchyma, it may not be visualized unless it has a displacement or contour effect. The better a system’s contrast resolution, the better the ability to distinguish between normal and abnormal tissues with similar echo amplitudes.
Homogeneity, Heterogeneity
Homogeneity (adj. homogeneous) and heterogeneity (adj. heterogeneous) are terms relating to the histologic make up of normal and abnormal tissues in relationship to their echogenic characteristics. Homogeneous structures are histologically uniform throughout whereas heterogenous structures are non uniform.
Solid masses are generally echogenic, with variable levels of echo amplitudes. Homogeneous solid masses have few reflectors and will appear to be relatively echo poor on the display. Conversely, solid masses that are heterogeneous contain numerous reflectors and will appear echogenic (variable levels of echogenicity dependent on several factors).
The terms homogeneous and heterogeneous may also be used to describe the echogenic appearance of structures. Structures that are homogeneous display a uniform echo pattern and the tissue texture will have a uniform dot size, distribution, and brightness. A good example of a normal structure with a homogeneous appearance is the spleen (see atlas figure 1-13). Conversely, structures that are heterogeneous display a non-uniform echo pattern. Liver with metastases frequently has a heterogeneous echo appearance (see atlas figure 1-14).
Solid, Cystic, and Complex Structures
Scanned structures may be described as being solid, cystic or complex when displayed depending on their sonographic appearances. Solid structures are composed of tissue and are associated with variable levels of echogenicity. They may be either homogeneous or heterogeneous, and exhibit variable degrees of attenuation. In comparison to cystic structures, solid structures are echogenic and are associated with average to above average attenuation. The testes and liver are two examples of solid structures. See atlas figure 1-10 for an example of a solid, hyperechoic renal mass.
Cystic structures contain fluid. In comparison to solid structures, cystic structures
are anechoic, and associated with decreased attenuation and the display of acoustic enhancement. Simple cysts are anechoic, have a thin well-defined walls, and produce good acoustic enhancement. See atlasfigure 1-9. Complex cysts are cysts that feature one or more of the following characteristics - echogenic fluid (diffuse or layered), septations, or a thick or irregular wall. See altas figure 1-15. Complex masses contain both solid tissue and fluid. See atlas figure 1-16.
Texture is the echo pattern (dot size, distribution and brightness) generated by tissues. The displayed echo texture depends on several technical factors including transducer frequency, dynamic range, output power, gain, and pre- and postprocessing algorithms. Speckle is the displayed dot pattern of organ parenchyma due to constructive and destructive wave interference from adjacent scatterers. The result of this acoustic interference produces a display dot pattern that does not represent the individual scatterers in the tissue but rather represents the resultant interference pattern from all the scatterers within the region. Speckle is considered a type of acoustic artifact which degrades tissue echo texture. Speckle tends to produce a very fine dot pattern in the near field which become coarser in the far field because attenuation filters out the higher frequency echoes. See atlas figure 1-17. The sonographer can not correct acoustic speckle (only recognize it for what it is). Since speckle is not a favorable acoustic event, equipment manufacturers continue to work to reduce it.
د.كمال سيد Admin
عدد المساهمات : 2690نقاط : 4494السٌّمعَة : 9الجنس : علم بلدك : تاريخ الميلاد : 03/04/1950تاريخ التسجيل : 30/07/2012العمر : 74 الموقع : السودان - سنارالعمل/الترفيه : طبيب عمومى وموجات صوتيةالساعة الان : دعائي :
موضوع: رد: US Vocabulary & terminology الثلاثاء أبريل 23, 2019 4:20 pm
اليكم مزيد من المصطلحات التى تعترض طريقنا فى فهم اساسيات الموجات الصوتية
Acceleration - increase in velocity per unit time.
Aneurysm - a sac formed by the localized dilatation of the wall of an artery, vein, or the heart.
Atherosclerosis - a common form of arteriosclerosis in which deposits of yellowing plaques (atheromas) containing cholesterol, other lipoid material, and lipophages are formed within the intima of large and medium-sized arteries. The word atherosclerosis comes form the Greek, athere, meaning “soft, fatty, gruel-like,” and scler- meaning “hard”. These terms are descriptive of the material deposited on the intima of an artery and of the state of the arterial muscle walls once they have been affected by the disease.
Bernoulli effect - pressure reduction in a region of high flow velocity.
Compliance - dispensability; nonrigid stretchability of vessels. adj. compliant -
Energy - power that may be translated in motion (kinetic), overcoming resistance, or effecting physical change; the ability to do work. Energy assumes several forms; it may be thermal (in the form of heat), electrical, mechanical, chemical, radiant, or kinetic. In doing work, the energy is changed from one form to another or to several forms. In these changes some of the energy is “lost” in the sense that it cannot be recaptured and used again. Usually there is loss in the form of heat, which escapes or is dissipated unused. All energy changes give off a certain amount of the energy as heat.
Flow - the movement of a liquid or gas.
Flow resistance - pressure difference divided by volume flow rate for steady flow.
Friction - the force that resists the movement of one object on another. inertia - resistance to acceleration.
Intima - the innermost lining of a blood vessel. Also called tunica intima.
laminar flow - flow in which fluid layers slide over each other in a smooth, orderly manner, with no mixing between layers.
Poiseuille’s law - the mathematical description of the dependence of volume flow rate on pressure, vessel length, radius, and fluid viscosity.
Pressure - force divided by area in a fluid. blood p. - the pressure of the blood on the walls of the arteries, dependent on the energy of the heart action, elasticity of the arterial walls, and volume and viscosity of the blood; The maximum or systolic pressure occurs near the end of the stroke output of the left ventricle, and the minimum or diastolic late in ventricular diastole. Pulse pressure. - the difference between the systolic and diastolic blood pressures.
Pulsatile flow - flow that accelerates and decelerates with each cardiac cycle.
Stenosis - a narrowing of the lumen of a blood vessel, most commonly due to atherosclerosis.
Turbulent flow - also turbulence; random, chaotic, multidirectional flow of a fluid with mixing between layers; nonlaminar flow.
Velocity (linear) - refers to the rate of displacement of a particle with respect to time. The units used to describe velocity are distance per unit time e.g. cm/sec.
Viscosity - resistance of a fluid to flow; a physical property of a fluid that is dependent on the friction of the component molecules as they slide by one another. adj. viscous - having a high degree of viscosity.
Volume flow rate - the volume of a fluid that passes through an organ or part in a specified time. Expressed in units of volume per unit time, i.e. cm /sec. يتبع
د.كمال سيد Admin
عدد المساهمات : 2690نقاط : 4494السٌّمعَة : 9الجنس : علم بلدك : تاريخ الميلاد : 03/04/1950تاريخ التسجيل : 30/07/2012العمر : 74 الموقع : السودان - سنارالعمل/الترفيه : طبيب عمومى وموجات صوتيةالساعة الان : دعائي :
موضوع: رد: US Vocabulary & terminology الثلاثاء أبريل 23, 2019 4:21 pm
اليكم مزيد من المصطلحات التى تعترض طريقنا فى فهم اساسيات الموجات الصوتية
Acceleration - increase in velocity per unit time.
Aneurysm - a sac formed by the localized dilatation of the wall of an artery, vein, or the heart.
Atherosclerosis - a common form of arteriosclerosis in which deposits of yellowing plaques (atheromas) containing cholesterol, other lipoid material, and lipophages are formed within the intima of large and medium-sized arteries. The word atherosclerosis comes form the Greek, athere, meaning “soft, fatty, gruel-like,” and scler- meaning “hard”. These terms are descriptive of the material deposited on the intima of an artery and of the state of the arterial muscle walls once they have been affected by the disease.
Bernoulli effect - pressure reduction in a region of high flow velocity.
Compliance - dispensability; nonrigid stretchability of vessels. adj. compliant -
Energy - power that may be translated in motion (kinetic), overcoming resistance, or effecting physical change; the ability to do work. Energy assumes several forms; it may be thermal (in the form of heat), electrical, mechanical, chemical, radiant, or kinetic. In doing work, the energy is changed from one form to another or to several forms. In these changes some of the energy is “lost” in the sense that it cannot be recaptured and used again. Usually there is loss in the form of heat, which escapes or is dissipated unused. All energy changes give off a certain amount of the energy as heat.
Flow - the movement of a liquid or gas.
Flow resistance - pressure difference divided by volume flow rate for steady flow.
Friction - the force that resists the movement of one object on another. inertia - resistance to acceleration.
Intima - the innermost lining of a blood vessel. Also called tunica intima.
laminar flow - flow in which fluid layers slide over each other in a smooth, orderly manner, with no mixing between layers.
Poiseuille’s law - the mathematical description of the dependence of volume flow rate on pressure, vessel length, radius, and fluid viscosity.
Pressure - force divided by area in a fluid. blood p. - the pressure of the blood on the walls of the arteries, dependent on the energy of the heart action, elasticity of the arterial walls, and volume and viscosity of the blood; The maximum or systolic pressure occurs near the end of the stroke output of the left ventricle, and the minimum or diastolic late in ventricular diastole. Pulse pressure. - the difference between the systolic and diastolic blood pressures.
Pulsatile flow - flow that accelerates and decelerates with each cardiac cycle.
Stenosis - a narrowing of the lumen of a blood vessel, most commonly due to atherosclerosis.
Turbulent flow - also turbulence; random, chaotic, multidirectional flow of a fluid with mixing between layers; nonlaminar flow.
Velocity (linear) - refers to the rate of displacement of a particle with respect to time. The units used to describe velocity are distance per unit time e.g. cm/sec.
Viscosity - resistance of a fluid to flow; a physical property of a fluid that is dependent on the friction of the component molecules as they slide by one another. adj. viscous - having a high degree of viscosity.
Volume flow rate - the volume of a fluid that passes through an organ or part in a specified time. Expressed in units of volume per unit time, i.e. cm /sec. يتبع
موضوع: US Vocabulary & terminology 
الثلاثاء أبريل 23, 2019 4:13 pm
