2. ➔ ULTRASOUND also called as SONOGRAPHY or DIAGNOSTIC
MEDICAL SONOGRAPHY is an imaging method that uses sound waves to
produce images of structures within your body.
➔ Ultrasound imaging produces valuable information for diagnosing treatment
for a variety of diseases.
➔ This scanning method uses high - frequency sound waves to make an image
of a person’s internal body structures.
INTRODUCTION ABOUT ULTRASOUND
3. Why Ultrasound Imaging is done ?
❏ View the Uterus during the Pregnancy for monitoring the Baby’s Health
❏ Evaluate Blood Flow
❏ Guide a needle for biopsy
❏ Tumor Treatment
❏ Check the Thyroid Gland
❏ Assess Joint Inflammation
❏ Evaluate metabolic bone Disease
❏ Diagnose Gallbladder Diseases
4.
5. Working Principle
● Medical ultrasound images are obtained by
transmitting high-frequency acoustic waves into
the body and reconstructing the received echoes
from the interfaces between the different tissue
types in the body.
● Ultrasound acoustic signals (generally in the 2–20
MHz frequency range) are generated by converting
a radio frequency (RF) electrical signal into
mechanical vibration.
6. What are the events that will happen ?
● The ultrasound machine transmits high-
frequency (1 to 5 megahertz) sound
pulses into your body using a probe.
● The sound waves travel into your body
and hit a boundary between tissues, like
fluid to soft tissue and soft tissue to
bone.
● Some of the sound waves get reflected
back to the probe, while some travel on
further until they reach another
boundary and get reflected.
● The reflected waves are picked up by the
probe and relayed to the machine.
● The machine calculates the distance from
the probe to the tissue using the speed of
sound in tissue and the time of the each
echo's return.
● The machine displays the distances and
intensities of the echoes on the screen.
● Here, millions of pulses and echoes are sent
and received per second. The probe can be
moved along the surface of the body and
angled to obtain various views.
7. Parts of Ultrasound Machine
● Transducer probe - probe that sends and receives the sound
waves.
● Central processing unit (CPU) - computer that does all of the
calculations and contains the electrical power supplies for itself
and the transducer probe.
● Transducer pulse controls - changes the amplitude, frequency
and duration of the pulses emitted from the transducer probe.
● Display - displays the image from the ultrasound data processed
by the CPU.
● Keyboard/cursor - inputs data and takes measurements from the
display.
● Disk storage device - stores the acquired images.
● Printer - prints the image from the displayed data.
8. 3D Ultrasound Imaging Doppler
Ultrasound
● Ultrasound machines capable of three-
dimensional imaging, here several two-
dimensional images are acquired by
moving the probes across the body
surface or rotating inserted probes. The
two-dimensional scans are then
combined by specialized computer
software to form 3D images.
● 3D imaging is best used for Early
detection of cancerous and benign
tumors.
● Doppler ultrasound is based upon the
Doppler Effect. Doppler ultrasound
measures the change in frequency of
the echoes to calculate how fast an
object is moving.
● Doppler ultrasound has been used
mostly to measure the rate of blood
flow through the heart and major
arteries.
9. ADVANTAGES OF ULTRASOUND MACHINE
● Ultrasound has been used in a variety of clinical settings, including
obstetrics and gynecology, cardiology and cancer detection.
● The main advantage of ultrasound is that certain structures can be
observed without using Radiation.
● Ultrasound can also be done much faster than X-rays or other
radiographic techniques.
10. LIMITATIONS IN ULTRASOUND IMAGING
Ultrasound Is a Safe-procedure that uses Low-power sound waves. There are no
known risks.
Limitations are :
Sound waves don’t travel well through air or bone , so ultrasound isn’t effective at
imaging body parts which are hidden by bone , such as the lungs or head.
Ultrasound may also be unable to see objects that are located very deep in the
human body.
11. The Future of Ultrasound
● Transducer probes may get smaller, and more insertable probes will be
developed to get better images of internal organs.
● Most likely, 3D ultrasound will be more highly developed and become more
popular.
● The entire ultrasound machine will probably get smaller, perhaps even hand-
held for use in the field of paramedics and battlefield triage , etc.
13. INTRODUCTION
● Computed tomography is commonly referred to as a CT scan.
● A CT scan is a diagnostic imaging procedure that uses a combination of X-rays and
computer technology to produce images of the inside of the body.
● It shows detailed images of any part of the body, including the bones, muscles, fat,
organs and blood vessels.
● A CT scan can be used to visualize nearly all parts of the body and is used to
diagnose disease or injury as well as to plan medical, surgical or radiation treatment.
14. Why CT is better than X-Rays ?
❏ CT scans are more detailed than standard X-rays. In standard X-rays, a beam of energy
is aimed at the body part, and a plate is placed behind the body part which captures the
variations of the energy beam after it passes through skin, bone, muscle and other tissue.
By doing so we obtain much information from a regular X-ray, but more detail about the
internal organs and other structures are not available.
❏ Whereas in CT, the X-ray beam moves in a circle around the body. This allows many
different views of the same organ or structure and provides much greater detail. The X-
ray information is sent to a computer that interprets the X-ray data and displays it in
two-dimensional form on a monitor.
