basics about ultrasound. helpful for better understanding ;)

1. PRINCIPLE OF
ULTRASOUND
NUR HANISAH ZAINOREN

2. ULTRASOUND
One of the imaging modalites with NO IONIZING
RADATION
Can image directly in any body plane
Sound waves with a frequency of 10-20Hz

4. PRINCIPLES
US machines utilize the pulse echo principle
US probe generates pulses of high frequency sound waves -
-> transmitted into the patient --> echoes returning from
various tissue boundaries (interfaces) --> detected by probe
--> processed by computer --> visualised as an image on
screen

27. ULTRASOUND
GEL
Ultrasound gel is a type of conductive
medium that enables a tight bond
(acoustic seal) between the skin and
the probe or transducer, letting the
waves transmit directly to the tissues
beneath and to the parts that need to
be imaged.

28. CLINICAL INTERPRETATION
OF ECHOGENICITY
The liver is usally used as the benchmark for echogenicity. *in
scrotal US, always compare the two testes*
Hypoechoic (darker and black) - Lymph node, GIT, Liver
masses
Hyperechoic (brighter and white) - Bone, Stone, Fat, Ligaments
Anaechoic / sonolucent (clear black; containing few or no echo)
- Gall bladder, Bladder, Cyst, Amniotic fluid
Isoechoic (similar echogenicities) - Spleen and Liver, Used
when speaking of comparisons

30. DOPPLER STUDY
When an US beam
encounters a moving
structure, a change in the
pitch and frequency of the
returning echo occurs
called as "DOPPLER SHIFT"
Image can be generate, giving
information about the speed
and direction of the moving
structure

31. TYPES OF DOPPLER
Color Doppler
Power Doppler
Spectral Imaging

32. COLOR DOPPLER
The displayed color
identifies the direction
of flow as well as the
speed of flow

33. POWER DOPPLER
Measures the concentration of
moving structures
More sensitive to low-flow
states, but does not allow an
evaluation of direction or
speed

34. SPECTRAL IMAGING
Estimation of the diameter
of the vessel in which the
cells are flowing by
calculating the velocity of
moving RBCs

35. REFERENCES
Concise The Radiology for Undergraduates, Bhushan N.
Lakhar, Chandrakant M. Shetty
http://www.slideshare.net/mobile/cbyrne2014/point-of-care-
ultrasound-yperechoic-future-in-medical-school
http://youtu.be/JqVGgq5bE-Y

36. “Thank you.”