wk 1-3 CVS100

Body Scan Planes, Terminology, How to obtain the images.

medial

toward the middle/midline of the body

lateral

away from the midline

proximal

• closer to the point of origin

• closer to the heart

distal

• farther from the point of origin

• farther from the heart

cephalad

superior,above, towards the head

caudal

inferior, below, towards the feet

superficial

closer to the surface/skin

deep

farther down from the surface/skin

anterior

towards the front of the body

posterior

towards the back of the body

supine

lying on the back

prone

laying on the stomach

right lateral recumbent

• lying on right side with the right arm extended and the left arm bent

• aka right lateral decubitus

left lateral recumbent

• lying on left side with the left arm extended and the right arm bent

• aka left lateral decubitus

Fowler’s

sitting

Trendelenberg

feet higher than head

Reverse trendelenberg

head higher than feet

ultrasound

• Very high frequency sound waves-millions of Hertz

• they bounce off of structures and blood inside the body to obtain images and flow signals.

• used for diagnostic purposes

transducer

• Any device that changes energy from one form into another

• Ultrasound probes turn electrical energy into mechanical vibrations of the crystals, producing ultrasound waves, and which also changes the echoes back into electrical energy for display on the screen.

ultrasound probes turn ______ into __________ producing _____, and which also changes the ____ back into _____ for display on the screen.

• electrical energy

• mechanical vibrations of the crystals

• ultrasound waves

• echoes

• electrical energy

Beam

ultrasound emitting from the transducer

whatever the _____ will appear on your image.

beam transects

lower frequency is used to scan _____ structures.

deeper

higher frequency is used to scan _____ structures.

more superficial

lower frequency resolution

• 2.5 - 4 MHz

• echo and abdominal

• loss of some resolution (reduced image resolution, less detail)

higher frequency resolution

• vascular

• better resolution (5-10 MHz)

Linear array

• 4cm wide

• rectangle field of view

• created by a line of many crystals

curved linear

line of crystals, but it is curved to create a sector (pie) shaped field of view

phased array

pie-shaped sector; smaller probe face and creates a wider sector than the curved

nearfield on your ultrasound image is the area…

• closest to the transducer

• More superficial part of neck.

• Strongest signals are in the nearfield

midfield on your image is the

center of the image

farfield on your image is the

• area farther away from the transducer

• the more deeper part of your neck or body

• Weakest signals are in farfield (bottom)

Time Gain Compensation and Lateral Gain Compensation

•Adjusts the brightness of the image in specific sections.

•Compensate for weaker signals

Overall Gain/ 2D Gain

• Adjusts the brightness of the entire image.

• Makes the entire image brighter or darker.

depth

•Describes the maximum distance into the body that an ultrasound system is imaging.

•Adjusts how far or how close we see into the body.

focal zone: focus/trans zone

• enhances the focus and resolution to a specific anatomical structure

•Always adjust to the area of interest

color flow doppler

• shows blood flow motion in a selected two-dimensional area. 

• shows Direction and velocity blood flow.

• direction and blood flow are color coded and superimposed on the corresponding B-mode image

spectral doppler

• consists of a continuous pulsed-wave form.

• Shows the velocities of moving RBCs

• shown to you as a Spectral Waveform.

anechoic

being without echo (black) appearance on image

echogenic

The ability to create an ultrasound echo

hyperechoic

Producing echoes of higher amplitude than normal for the surrounding medium

hypoechoic

Producing echoes of lower amplitude than normal for the surrounding medium

homogeneous

•Completely uniform in texture or composition.

•Same grayscale

heterogeneous

• an uneven echo pattern

• reflections of varying grayscale

• not uniform in texture or composition.

acoustic enhancement

•When ultrasound passes through a fluid medium, the intensity of the sound energy is not diminished.

•tissues behind the fluid collection are more echogenic (brighter because there is more acoustic power to reflect back to the transducer).

For acoustic enhancement, tissues behind the ___ ___ are more ___ (brighter).

• fluid collection

• Echogenic

acoustic shadowing

When ultrasound hits a dense object the ultrasound beam can not propagate(travel) through the dense object. The beam will be completely reflected, a posterior acoustical shadow is formed.