terms Flashcards
In sagittal plane, describe inferior, superior, anterior, and posterior.
Inferior is towards the caudal.
Superior is towards the head.
Anterior is towards the skin.
Posterior is towards the spine.
Sagittal (longitudinal) view measures:
length (Cranial-Caudal/ height(Anterior to posterior
Transverse (Axial) view measures:
Width, height
Coronal view measures:
(width, height), dependent on slice thickness measuring A-P
Define Gray scale:
an image produced from a range from whites to blacks, digital is dependent on bit depth
Define contrast.
The difference between blacks and whites, High contrast is a large difference producing an images of few grays. Low contrast is small differences, producing a very gray image
Define contrast media.
any substance that provides more contrast between anatomical structures which separates them visually. May be a metal, air, injected compound.
Supine position
patient lies on their back
lateral position
patient lies on their side
prone position
patient lies on their stomach
Modified fowler position
patient lies on their back with the head elevated and knees flexed
Trendelenburg position
patient lies on their back and their pelvis and legs are higher than their head
A-mode
amplitude modulation;
a one-dimensional representation of a reflected sound wave.
Amplitude
the intensity of a signal determined by its brightness and height above the baseline.
Anechoic
not producing echoes;
appears black on screen
artifacts
echoes that do not correspond to real structures.
B-mode
Brightness modulation;
2d presentation of echo-producing interfaces which are displayed at the correct depth from the transducer.
Continuous wave (CW) doppler
continuous generation of ultrasound waves coupled with continuous ultrasound reception used to evaluate blood flow.
cystic
a fluid-filled sac;
anechoic
appears black on screen
creates posterior enhancement
Doppler
ultrasound utilizing the Doppler effect to measure movement or flow in the body, especially blood flow.
echogenicity
the characteristic of tissue to reflect sound waves and produce echoes.
echoic
producing echoes
enhancement (acoustic)
appearance of increased echo brightness from tissue lying beyond a structure in which attenuation is low
focal zone
the narrowest part of the sound beam in which resolution is greatest.
gain
amount of amplification of returning echoes.
gel
medium used to exclude air from between the surface of the trasnducer and the patinetnt’s body.
grayscale
series of shades from white to black.
heterogeneous
composed of differing echo types
homogeneous
composed ot similar echo types
hyperechoic
more echogenic.
appears lighter.
compares two or more structures.
hypoechoic
less echogenic
appears darker.
compares two or more structures
isoechoic
having the same echogenicity.
compares two or more structures.
M-mode
motion mode;
presentation of moving structures along a single line in the ultrasound beam dispalyed as time versus distance from the transducer.
noise
an artifact usually caused by excessive system gain.
piezoelectric
a property of certain crystals that causes them to produce voltage when mechanical pressure, such as sound vibration, is applied to them and vice versa.
Power doppler
demonstration of the amplitude of doppler signals rather than the frequency shift.
Pulsed-wave (PW) doppler
the use of a sample volume that gives a graphic display of all the velocities contained within a sampled area.
Shadowing
the loss of echo signals from distal structures as a result of attenuation from overlying structures that are highly attenuative.
Time-gain compesation (TGC)
process in which receiver amplification is increased with time so that echo signals originating form distant reflectors are amplified more than echo signals originating form reflectors close to the transducer so that like reflecctors have the same appearance.
anterior
towards the front
caudal
towards the feet
cephalic
towards the head or pertaining to the head
contralateral
the other side.
cranial
pertaining to the craniium or towards the head
distal
a position farther from the point of reference
dorsal
towards the back
inferior
below
ipsilateral
on the same side
lateral
a position farther from the median plane or midline of the body
longitudinal
the long axis of a strcutre or an organ
medial
a psoition closer to the midline of the body
oblique
any imaging plane that is not sagittal or transverse.
peripheral
located away from the center
posterior
behind
proximal
a position nearer ro the point of reference
Superior
above
ventral
towards the belly
CAAHEP
accredits entry-level allied health education programs.
TJC
accredits healthcare organizations like hospitals
Most prominent proffesional society for sonographers?
SDMS
Who certifies sonogrpahers?
ARDMS
