Sonography Chp. 7
Progressive diffuse disease could be characterized by a sonographer as:
"Liver shape appears altered with coarse, scattered increases in echogenicity and multiple fluid-filled, anechoic spaces 1 to 5 mm in diameter throughout"
A proper description of the Enlargement of the pancreas head, which can cause biliary duct obstruction, dilate the common bile duct(CBD), and compress the anterior surface of the inferior vena cava(IVC) would be:
"Pancreas appears heterogeneous and markedly hyperechoic relative to the liver. Small shadowing calcifications throughout, irregular outline are noted. Heard papers focally enlarged: 6 cm anteroposteriorly. There is posterior displacement (or anterior compression) of the IVC. CBD appears dilated: 12 mm. The duodenum is not seen."
Color Flow doppler
Doppler shift information in a two-dimensional presentation superimposed on a real-time gray scale anatomic cross-sectional image.
Deep inspiration forces the diaphragm and everything below it in the abdomen to move:
Down
Artifact
Echo features or structured observed on ultrasound images that are unassociated with the object being imaged
Endocavital scanning Plane Interpretations
Endovaginal imaging or Endorectal imaging are obtained from an inferior transcavital approach, which is technically organ oriented.
Scanning planes interpretations depend on the:
Location of the transducer ad the sound wave approach(where the sound waves enter the body)
LCM
Longus Colli Muscle
Medium
Material through which a wave travels
Depth of Penetration
Maximum distance the sound beam travels from the transducer through a medium.
MN
Median Nerve
As the infiltrative diseases advances, organ parenchyma can become:
More coarse or patchy looking with necrotic(degenerating), blood-build spaces
Ascites
accumulation of fluid in the abdominopelvic cavity
Simple cysts
are generally round and there may also exhibit refractive shadowing
Retroperitoneum
area of the abdominopelvic cavity located behind or posterior to the peritoneum
For an abdominal aorta the patient should be fasting for how long?
at least 8 hours, it reduces the amount of gas in the overlaying bowel
Axial (short axis) (view or section)
at right angles to longitudinal sections. term used to describe the section of a structure portrayed within a scanning plane image
Echopenic
few echoes
Anechoic
free from echoes on a sonographic image
TGC (time gain compensation)
increase in receiver gain with time to compensate for loss in echo amplitude, usually due to attenuation, with depth
AORTA TRV MID
inferior to the celiac trunk, at the level of the renal arteries, and along the length of the superior mesenteric artery
AORTA TRV PROX
inferior to the diaphragm and superior to the celiac trunk
Diffuse Disease
infiltrative disease throughout an organ that disrupts the otherwise normal sonographic appearance of organ parenchyma
Deep
internal; away from the body surface
A fourth "soft" simple cyst criterion
is the refractive edge shadows that emanate from the edge margins of rounded structures
Sonographer
technologist who performs sonography under a physician
What is true with vascular masses?
the appearance of the internal composition of any mass may very with time. -they may appear anechoic when the blood is fresh, but become complex and even solid as the blood thickness and eventually forms clots.
When diffuse disease causes enlargement of an organ, the sonographer must determine:
the extent of increase and describe whether any adjacent structures have been compromised.
Sonologist
the physician who interprets a sonogram
Focal Zone
the point at which the sound beam is the narrowest and the resolution is the best
ALARA (as low as reasonably achievable)
the prudent use of diagnostic sonography; dictates that the output level and exposure time to ultrasound is minimized while obtaining diagnostic data
Mirror image artifact (non-Doppler)
the sonographic image of a structure is duplicated in an atypical position and appears as a mirror image of the original
Septations
thin, membranous inclusion(s) within a mass
Parenchyma
tissue composing an organ
Superior (Cranial)
toward the head end or upper part of a structure or the body; above
Calipers (electronic)
two or more measurement cursors that can be manipulated to calibrate the distance between echoes of interest on the imaging screen
Beam Divergence
widening of the sound beam as it travels
Who is the only one who can legally renew a diagnosis?
A Physician
Refraction
A change in direction of sound as it passes through a boundary
Pleural Effusion
A collection of fluid inside the lung
Contrast
A comparison to show differences
Medial
Situated at, on, or toward the midline or midline of the body
Intraorgan Pathology
Abnormal disease process that originates within an organ.
Complex Mass
Abnormal mass within the body composed of both tissue and fluid.
True Cyst (Simple Cyst)
Abnormal mass within the body composed of fluid.
Solid Mass
Abnormal mass within the body composed of one thing, tissue.
Sagittal Plane
Divides body into left and right -Parallel to the long axis of the body
Parasagittal plane
Divides body into unequal right and left sides
Proximal
Situated closest to the point or origin or attachment
Ultrasound
Sound at frequencies above 20 Kilohertz or above the range of human hearing.
SH
Sternohyoid muscle
ST
Sternothyroid Muscle
Higher number megahertz (MHz) are best for imaging what structures?
Superficial
Transmission
Term implying passage of energy through a material
Neurosonography/ Neonatal Brain scanning Plan interpretations
The anterior fontanelle is used at the primary acoustic window or approach when imaging the neonatal brain. -In some instances the posterior fontanelle and mastoid fontanelles are utilized
What is very important to convey with the interpreting physician?
The appearance of mass borders
Interface
The boundary between two material or structures
Refractive shadows can also be visualized at:
The edges of the gallbladder neck and fungus when they are imaged longitudinally.
How is Calculi distinguished sonographically?
The fact that they reflect and impede or stop sound waves. -Their surface appears highly echogenic and bright, and posteriorly, they cast shadows -Posterior shadows generally present with sharp, well-defined edges
Case Presentation
The method of presenting the images and related details of an ultrasound study to the interpreting physician.
What happens to some solid masses, such as uterine fibroids over time?
They may degenerate
Peritoneum
Thin sheet of tissue that lines the peritoneal cavity and secretes serous fluid. -serves as a lubricant and facilitates free movement between organs Classified as: Parietal (Portion of lining that forms a closed sac) Visceral (Portion of lining that directly covers organs) intraperitoneal (Inside the sac) Retroperitoneal (Posterior or behind the sac)
THY
Thyroid
Inferior(Caudal)
Toward the feet Situated below or directed downward A structure lower than another structure
Anterior(Ventral)
Toward the front of the body
TR
Trachea
Documented areas if interest tor requires images must be represented in at least how many scanning planes?
Two -That are perpendicular to each other to give a more dimensional and therefore more accurate representation
The thermal Index (TI)and Mechanical Index (MI) are components of:
Ultrasound Bioeffects that should be monitored while scanning.
Reverberation
Ultrasound image artifact caused when sound waves pass through and beyond a structure whose acoustic impedance is noticeably different from an adjacent structure, causing a huge amount of reflection back to the transducer.
Sonographers acquire, asses, modify, analyze, document, and describe the ultrasound findings using:
Ultrasound terminology in a normal or written technical observation.
Deep exhalation forces the diaphragm and everything below it in the abdomen to move:
Upward
For an abdominal aorta what transducer is best?
Usually a 3.0 Or 3.5 MHz, If the patient is very thin. -A 5.0 MHz transducer may be the best choice.
VN
Vagus Nerve
Through Transmission
"Increased echo amplitude" or "acoustic enhancement" visualized posterior to a structure that does not attenuate (decrease, stop, impede or absorb) the sound beam. Considered a type of sonographic artifact.
Acoustic Enhancement
"Increased echo amplitude" or "posterior through transmission" visualized posterior to a structure that does not attenuate (decreased, stop, impede, or absorb) the sound beam. Considered a type of sonographic artifact. -- Bright posterior through transmission
Acoustic Shadows
"Reduced echo amplitude" or echo "drop off" posterior to a structure that attenuates (decreases, stops, impedes, or absorbs) the sound beam. Margins of the shadow are generally sharp and well defined. Considered a type of sonographic artifact.
A multilocular renal cyst could be described as:
"Renal mass with multiple, 1-to 3-cm, fluid-filled areas separated by highly echogenic, thin, linear, inclusions"
Diffuse infiltrative disease of the spleen can displace adjacent structures, particularly left kidney. A description might be:
"Speed appears enlarged and hyperechoic relative tot he left kidney, which is displaced inferomedially. Superior pole of the kidney appears flattened by lumpy contour of the spleen"
An infiltrative change in parenchyma may be described as simply as:
"The liver appears enlarged and hyperechoic compared to the pancreas"
It is standard practice to measure the long axis, greatest width, and greatest depth of a mass in order to calculate a volume measurement:
(L x W x AP)= V
Bones, Fat, Air, Fissures, Ligaments, Tendons, and the Diaphragm
-Appear echogenic ad vary in brightness depending on the density of the structure, its distance from the sound beam, and angle at which the beam strikes the structure -Because the structure either reflect or attenuate the sound beam, they appear hyperechoic/brighter compared with adjacent structures they may cast a posterior shadow.
Nerves
-Appearance is generally describes in comparison with adjacent structures: Hyperechoic when compared with the appearance of muscle; hypoechoic when compared with the appearance of tendons. -Peripheral nerve fibers present as very low gray or echo-poor with a distinctive internal echo pattern that appears stippled in axial sections and honey-combed longitudinal sections
When documenting abnormal finding you must document what?
-Determine the number(How many?) -Origin of the abnormality -The composition of the abnormality(Solid, cystic, complex) -Size of the abnormality with volume measurements -High and low gain images (gain range helps to resolve composition) - At least use two scanning planes
Extraorgan Features include:
-Displacement of other organs and structures - Obstruction of the organs or structures from view -Internal invagination of organ capsules -Discontinuity of organ capsules
Intraorgan features include:
-Disruption of the normal internal architecture -External bulging or organ capsules -Displacement or shift of adjacent body structures
Tissue
-Echo texture is homogenous or uniform and moderately echogenic -Margins appear very bright or hyperechoic compared with adjacent structures
Parenchyma
-Homogeneous or uniform echo texture with ranges in echogenicity (Can be described as homogenous and moderately echogenic)
Muscle
-Homogenous or uniform echo texture with LOW echogenicity -Appears hypoechoic or less echogenic relative tot he organs or body structures they are adjacent to. *Skeletal muscle bundles are DISTINCTLY separated by BRIGHT symmetric bands that appear hyperechoic or more echogenic compared with the low grey appearance of the muscle*
When describing the origin pf pathology, it is routine to classify localized disease as:
-Intraorgan (originates within an organ) -Extraorgan (originates outside an organ)
Fluid-filled structures
-Lumens appear anechoic(black; echo-free) -Walls appear bright; highly echogenic or hyperechoic compared with adjacent structures -May exhibit bright posterior through transmission, making them easy to distinguish sonographically
What is considered intraperitoneal?
-The Liver (except the bare area posterior to the dome) -Gallbladder -Spleen(Except for the hilum) -Stomach -Majority of the Intestines Ovaries
Placenta
-The echo texture changes throughout pregnancy; from homogenous or uniform with moderate to high echogenicity to heterogenous or mixed echo pattern. When interrupted by multiple vascular components -Normally hyperechoic or brighter appearance relative to uterine myometrium
Gastrointestinal Tract (GI)
-Walls are thin and generally appear less echongenic compared with adjacent structures. However they can appear very bright if they're surrounded by fat. -The GI appearance lumen varies depending on its content -A fluid-filled lumen appears anechoic -Empty collapsed bowel has a distinctive "Bull's Eye" due to the contrast between the very bright, collapsed lumen and hypo echoic walls
Solid tissue masses are characterized sonographically in the same manner as soft tissue organs, with the terms:
-homogenous -heterogenous -isosonic -hyperechoic -hypoechoic
The level of echogenicity and appearance of tissue texture depend on
-what type of localized disease is present -the degree of its density - its effect on internal architecture
Which 2 situations in which posterior through transmission criterion may be difficult to meet?
1. A cyst located deep in the body beyond the focal zone of the transducer, which means not enough sound waves are being generated to pass through the fluid to the create the enhancement effect. 2. A cyst located directly anterior to a bony structure, which absorbs the sound waves, preventing through transmission
To be considered a simples or a true cyst, the mass in question must meet 3 sonographic criteria which are:
1. Mass must appear anechoic with no internal echoes 2. Mass walls must be well defined, thin, and smooth 3. Mass must exhibit posterior through transmission or increase echo amplitude visualized posterior to a structure that does NOT attenuate the sound beam.
Attenuation
A decrease in intensity as sound enters deeper tissues
A localized change in the normal appearance of parenchyma represents:
A mass or multiple mass, which are circumscribed to a specific area.
What Position should patient be when scanning the aorta?
A supine position will be used as the best position
Your first scan will be of what?
Abdominal aorta
intraperitoneal
Abdominopelvic structures enclosed in the sac formed by the parietal peritoneum.
In most institutions, abnormal ultrasound findings are documented when?
After a scanning protocol's sequence of requires images. -they're amp documented in at least two scanning planes
Infiltrative diffuse disease spreads throughout?
An entire organ -Parenchymal texture is altered and often appears heterogeneous with varying degrees of echogenicity
Coronal Scanning Planes
Any plane parallel to the long axis of the body and perpendicular to sagittal scanning planes.
Orthogonal
At right angles; perpendicular
Doppler(Effect)
Change in observed sound frequency used by relative motion between the source of the sound or defector and the observer
Isogenic/isosonic
Comparative term used to describe an area in a sonographic image where the echo patterns are equal in echogenicity.
Labeling an image should never what?
Cover any part of the image or it can interfere with a diagnosis.
Complex masses may be primarily:
Cystic or primarily solid
Transverse Plane
Divides the body into unequal superior and inferior sections -Perpendicular to the long axis of the body
Lower number megahertz (MHz) are best for imaging what structures?
Deeper
Heterogeneous
Describes an irregular or mixed echo pattern on a sonographic Image.
Echo Texture
Describes the sonographic appearance of soft tissue structures within the body.
Homogeneous
Describes uniform or similar echo patterns on a sonographic image.
What is another example of. diffuses that can affect neighboring structures?
Enlargement of the pancreas head, which can cause biliary duct obstruction, dilate the common bile duct(CBD), and compress the anterior surface of the inferior vena cava(IVC) *some of these cases present with duodenal obstruction as well*
E
Esophagus
Superficial
External Situated on or toward the surface
AORTA SAG MID
Inferior to the celiac trunk; along the length of the superior mesenteric artery
AORTA SAG PROX
Inferior to the diaphragm and superior to the celiac trunk
AORTA TRV DISTAL
Inferior to the superior mesenteric artery ad superior to the bifurcation
AORTA SAG DISTAL
Inferior to the superior mesenteric artery; superior to the bifurcation
JV
Jugular Vein
Neoplasm
New, abnormal growth of existing tissues; either benign or malignant.
If one of the three simple cyst criteria is not met, the mass is:
Not a true cyst *A mass that only meets one or two of these criteria is said to be cystic in nature*
OH
Omonhyoid muscle
Mass descriptions should include:
Origin(or location), size, composition, number, and any associated complications with adjacent structures
Lateral
Pertaining to the right or left of the middle or midline of the body. -Describes the structure situated at, on or toward the side
Longitudinal (view or section)
Pertains to length; running lengthwise.
Sonogram
Pictorial record with ultrasound
It is important to note that not all distal shadows visualized with sonography are:
Representative of pathology
Acoustic Impedance
Resistance a material provides to the passage of sound waves
Crura Of Diaphragm
Right and left crus or fibromuscular bands arising from the lumbar vertebrae that insert into the central tendon of the diaphragm.
Posterior(dorsal)
Situated at or directed toward the back. A structure behind another structure
What is a bifurcation alternative if in longitudinal is still unresolved?
Visualize from a Coronal plane. -Patient positions in a right lateral decubitus. -Left lateral approach
When a solid mass appears isotonic tot he organ parenchyma it is part of, the mass is only distinguishable by its:
Walls -This border differentiation may be the only clue to the presence of the isotonic mass or masses
Where do you begin to scan the aorta in a Sagittal Plane?
With the transducer perpendicular, at the midline of the body just inferior to the xiphoid process of the sternum
Can all abnormalities and pathology be evaluated and documented the same way?
Yes
How to distinguish the Abdominal aorta from the Inferior Vena Cava (IVC)?
You Slightly move or angle the transducer from the midline position to the patients right. -A long, tubular anechoic structure with bright walls should come into view posterior to the liver passing through the diaphragm. *Note: IVC towards Sonographer and Aorta away from Sonographer*
Transducer (ultrasound)
a device capable of converting electrical energy to mechanical energy and vice versa
Mesentery
a double layer of peritoneum that attaches intraperitoneal organs to the abdominal cavity wall.
Extraorgan pathology
abnormal disease process that originates outside of an organ
Mass
circumscribed disease process
CCA
common carotid artery
Hyperechoic
comparative term used to describe an area in a sonographic image where the echoes are brighter relative to surrounding structures
Hypoechoic
comparative term used to describe an area in a sonographic image where the echoes are not as bright compared to surrounding structures
Calculi/"stones"
concentration of mineral salts that may accompany some disease processes
Necrotic
degeneration or "death" of tissue
Echogenic
describes a structure that is able to produce echoes or echo patterns on sonograms
Cystic
describes the sonographic appearance of a fluid collection within the body that does not meet the criteria to be considered a true cyst
Infiltrative Disease
diffuse disease process that spreads throughout an entire organ
Focal/multifocal change
disease process confined to isolated area(s) of an organ
Midsagittal plane
divides the body into equal right and left sides
Coupling Agent
substance used to reduce air between the ultrasound transducer and surface of the skin
Systemic
pertaining to the body as a whole
RLN
recurrent laryngeal nerve
Localized Disease
represents a circumscribed mass or multiple masses
Long axis (view or section)
represents the longest length of a structure
Gray Scale
scale of achromatic colors having multiple graduations from white to black
Distal
situated farthest from the point of origin
Contralateral
situated on or affecting the opposite side of the body
Ipsilateral
situated on or affecting the same side
SCM
sternocleidomastoid muscle