Imaging modalities Part 1 Flashcards
also called sonography
Ultrasound
It involves exposing part of the body to high-frequency sound waves to produce an image of a particular structure of the body.
Ultrasound
captured in real- time, it can show the structure and movement of the bodys internal organs, as well as blood flowing through blood vessels.
Ultrasound
consist of a console containing a computer and electronics, a video display screen and a transducer that is used to do the scanning.
Ultrasound scanners
is a small hand-held device that resembles a microphone, attached to the scanner by a cord.
Transducer
sends out inaudible high frequency sound waves into the body and then listens for the returning echoes from the tissues in the body.
Transducer
The ultrasound image is immediately visible on a video display screen that looks like a computer or television monitor.
Transducer
The image is created based on the amplitude (strength), frequency and time it takes for the sound signal to return from the area of the patient being examined to the transducer and the type of body structure the sound travels through.
Transducer
The essential element of each ultrasound transducer is a
piezoelectric crystal
It serves to generate as well as receive ultrasound waves.
piezoelectric crystal
Types of Ultrasound Transducers:
- Liner transducer
- Convex transducer
- Phased array transducer
the piezoelectric crystal arrangement is linear, the shape of the beam is rectangular, and the near-field resolution is good.
linear transducer
The footprint, frequency, and applications of the linear transducer depend on whether the product is for 2D or 3D imaging
Linear transducer
an be use for various applications, such as: Vascular examination, Venipuncture, blood vessel visualization, Breast, Thyroid, Tendon.
linear transducer for 2D imaging
Can be use for various applications, such as: Breast, Thyroid Arteria carotis of vascular application.
linear transducer for 3D imaging
also called the curved transducer because the piezoelectric crystal arrangement is curvilinear.
Convex transducer
beam shape is convex and the transducer is good for in-depth examinations, even though the image resolution decreases when the depth increases.
Convex transducer
The footprint, frequency, and applications also depend on whether the product is for 2D or 3D imaging.
Convex transducer
Can be use for various applications, such as: Abdominal examinations, Diagnosis of organs Transvaginal and transrectal examinations
convex transducer for 2D imaging
Can be use for abdominal examinations.
convex transducer for 3D imaging
This transducer is named after the piezoelectric crystal arrangement which is called phased-array and it is the most commonly used crystal Phased Array transducer.
Phased Array Transducers
Has a small footprint and low frequency (its central frequency is 2Mhz – 7.5Mhz)
Phased Array Transducers
The beam point is narrow but it expands depending on the applied frequency.
Phased Array Transducers
The beam shape is almost triangular and the near-field resolution is poor
Phased Array Transducers
Can be use for various applications, such as: Cardiac examinations, Abdominal examinations and Brain examinations
Phased Array Transducers
probe that sends and receives the sound waves.
Transducer probe
computer that does all of the calculations and contains the electrical power supplies for itself and the transducer probe
Central processing unit (CPU)
changes the amplitude, frequency and duration of the pulses emitted from the transducer probe
Transducer pulse controls
displays the image from the ultrasound data processed by the CPU
Display
inputs data and takes measurements from the display
Keyboard/cursor
stores the acquired images
Disk storage device (hard, floppy, CD)
prints the image from the displayed data
Printer
Advantages of Ultrasound
- Mobility
- Cost-effective
- patient-friendliness (no radiation)
- Applied in obstetrics, cardiology, inner medicine, urology
