Ultra sound in Physiotherapy

1. ULTRASOUND

2. Frequency:
▫ Audible sound – 20 to 20000Hz
▫ Ultrasound – Greater then 20000Hz
▫ Infrasound – Less than 20Hz
▫ Medical ultrasound – 2.5 - 40 MHz
 In physics, the term "ultrasound" applies to all
acoustic energy (longitudinal, mechanical wave)
with a frequency above the audible range of human
hearing.
 The audible range of sound is 20 hertz-20 kilohertz.
Ultrasound is frequency greater than 20 kilohertz.

3. WHY ULTRASOUND?
Ultrasound (US) is the most widely used imaging
technology worldwide due to
• availability
• Speed
• low cost,
• patient-friendliness (no radiation)

4. Ultrasonography is widely utilized in medicine, primarily in
 Gastroenterology
 Cardiology
 Gynecology and obstetrics
 Urology
•Bursitis (Bursitis is the inflammation of a bursa, typically
one in a shoulder joint)
•Tendonitis (A condition in which the tissue connecting
muscle to bone becomes inflamed)
•Muscle Strain and tears
•Osteoarthritis
•Ligament and tendon injuries
Where do we use USG

5.  Ultrasound can help relax tight muscles that are
sore and warms muscles and soft tissues, which
increases circulation that helps to heal.
 sound waves penetrate the skin's surface causing
soft tissues to vibrate,
creating heat.
 The heat induces
vasodilation: drawing blood
into the target tissues.
Increased blood flow
delivers needed oxygen
and nutrients, and removes cell wastes.
 The heat helps relieve pain and inflammation,
reduce muscle spasms, and accelerate healing.
Depending on the treatment area, the range of
motion may be increased.

6. Ultrasound is also used to:
Guide procedures such as
needle biopsies, in which
needles are used to extract
sample cells from an abnormal
area for laboratory testing.
Diagnose a variety of heart conditions and assess
damage after a heart attack or diagnose valvular heart
disease.
Image the breasts and
guide biopsy of breast
cancer

7. ULTRASOUND INSTRUMENT

8. ULTRASOUND MACHINE
A basic ultrasound machine has the following parts:
1. Transducer probe - probe that sends and receives
the sound waves
2. Central processing unit (CPU) - computer that does
all of the calculations and contains the electrical power
supplies for itself and the transducer probe
3. Transducer pulse controls - changes the amplitude,
frequency and duration of the pulses emitted from the
transducer probe
4. Display - displays the image from the ultrasound data
processed by the CPU
5. Keyboard/cursor - inputs data and takes
measurements from the display
6. Disk storage device (hard, floppy, CD) - stores the
acquired images
7. Printer - prints the image from the displayed data

9. HOW IS THE PROCEDURE PERFORMED?
 For most ultrasound exams, the patient is positioned
lying face-up on an examination table that can be tilted
or moved.
 A clear water-based gel is applied to the area of the
body being studied to help the transducer make secure
contact with the body and eliminate air pockets between
the transducer and the skin that can block the sound
waves from passing into your body.
 The sonographer (ultrasound technologist) or radiologist
then presses the transducer firmly against the skin in
various locations, sweeping over the area of interest or
angling the sound beam from a farther location to better
see an area of concern.

10. ATTENUATION OF ULTRASOUND IN THE
TISSUES:
• The loss of energy from the ultrasound beam in the
tissues is called attenuation and depends on both
absorption and scattering
• Absorption accounts for some 60 – 80% of the
energy loss. The scattered energy may also be
absorbed other than in the region to which the
ultrasound beam is applied.
• Scattering is caused by reflections and refractions,
which occur at interfaces throughout the tissues. This is
particularly apparent where there is a large difference
in acoustic impedance.

11. ABSORPTION OF SONIC WAVES
• Kinetic energy is converted to heat energy as it passes
through the material.
• The energy will decrease exponentially with distance
from the source because a fixed proportion of it is
absorbed at each unit distance so that the remaining
amount will become a smaller and smaller percentage
of the initial energy
• The conversion of sonic energy to heat is due to
increased molecular motion

12.  Kinetic energy is converted to heat energy as it passes
through the material.
 The conversion of sonic energy to heat is due to increased
molecular motion
 Absorption of sonic energy is greatest in tissues
with largest amounts of structural protein
and lowest water content.
 Blood – least protein content and least
absorption
 Bone - greatest protein content and greatest
absorption

14. • Effect of Frequency:
Increasing the frequency of
Ultrasound causes a
decrease in its depth of
penetration and concentration
of the Ultrasound energy in
the superficial tissues.
1MHz 3MHz
Muscle 9.0mm 3.0mm
Fat 50.0mm 16.5mm
Tendon 6.2mm 2.0mm

15. Thermal effects:
• The advantage of using ultrasound to achieve
heating is due to the preferential heating of
collagen tissue and to the effective penetration of
this energy to deeply placed structures.
• Heating fibrous tissue structures such as joint
capsules, ligaments, tendons, and scar tissue
may cause a temporary increase in their
extensibility, and hence a decrease in joint
stiffness.
• Mild heating can also have the effect of reducing
pain and muscle spasm and promoting healing
processes.

16. Therapeutic Uses:-
Ultrasound promotes healing of varicose ulcers and
pressure sores (decubital ulcer).
• Varicose Ulcer: Ulcer in the leg
• associated with varicose veins
• is known as varicose ulcer.
• Pressure Sore: A bed sore appearing on dependent
sites usually on lumbosacral region, most commonly
in bed- ridden elderly persons is known as pressure
sore.

17. Pain relief:
• Ultrasound is used in herpes zoster, low backache,
prolapsed intervertebral disc (PIV) and many other
condition
• (Herpes zoster, is a viral disease
characterized by a painful skin rash
with blisters in a localized area)
Acute tissue injury:-
• Ultrasound is used in soft tissue and sport injuries, in
occupational injuries and post-natal injuries. It is used
for perineal post-natal pain, for painful shoulders and for
both neurogenic & chronic pain.

18. Scar Tissue:-
• Ultrasound improves the quality of scar tissue and
excessive fibrous tissue. It is used in conditions like
Dupuytren’s contracture and plantar fasciitis.
(Dupuytren's contracture is
a condition in which one or
more fingers become permanently
bent in a flexed position)
(Plantar fasciitis is An
inflammation of a thick band
of tissue that connects the
heel bone to the toes)

19. Bone injury:-
• Ultrasound therapy in the first 2 weeks after bone
injury can increase bones union. Ultrasound has also
been used in the early diagnosis of stress fractures
(A stress fracture is a small crack in a bone).
Chronic Indurated Oedema:
• The mechanical effect of ultrasound has an effect on
chronic oedema and helps in its treatment.
(Oedema - a condition characterized by an excess of
watery fluid collecting in the cavities or tissues of the
body)

20. Contraindications
• Tumors – it might encourage neoplastic
growth(abnormal growth) and provoke metastases or
over precancerous tissue should be avoided
• Pregnant Uterus – avoid applying ultrasound over a
pregnant uterus, the probable risk to the rapidly dividing
and differentiating cells of the embryo and fetus
• Spread of Infection - Bacterial or viral infection could
be spread by ultrasound, presumably by facilitating
microorganism movement across membranes and
through the tissues.
• Tuberculosis - Due to the possible risk of reactivating
encapsulated lesions tuberculous regions should not be
treated.
(a region in an organ or tissue which has suffered damage through injury or
disease, such as a wound, ulcer, abscess, or tumour)

21. Dangers of Ultrasound:
• There are very less evidences of dangers of ultrasound
but it may occur in some conditions only.
– Burns could occur if the heat generated exceeded the
physiological ability to dissipate it.
– Tissue destruction would result from transient
cavitation.
– Blood cell stasis and endothelial damage (a type of
coronary artery disease) may occur if there is standing
wave formation.
(cell stasis -A stoppage or slowdown in the flow of blood)

22. Strengths of ultrasound imaging:
 It images muscle and soft tissue very well and is
particularly useful for indicating the exact position,
and the interfaces between solid and fluid-filled
spaces.
 It renders "live" images, where the operator can
dynamically select the most useful section for diagnosing
and documenting changes, often enabling rapid diagnoses.
 It shows the structure as well as some aspects of the
function of organs.
 It has no known long-term side effects and rarely causes
any discomfort to the patient.
 Equipment is widely available and comparatively flexible;
examinations can be performed at the bedside.

23. Weaknesses of ultrasound imaging:
 Ultrasound cannot penetrate bone and performs
poorly when there is air between the scanner and the
organ of interest. For example, overlying gas in the
gastrointestinal tract often makes ultrasound scanning
of the pancreas difficult.
 Even in the absence of bone or air, the depth
penetration of ultrasound is limited, making it difficult
to image structures that are far removed from the
body surface, especially in obese patients.
 The method is operator-dependent. A high level of
skill and experience is needed to acquire good-
quality images and make accurate diagnoses.

24.  Ultrasonography is generally considered a "safe"
imaging modality.
 Diagnostic ultrasound studies of the fetus are
generally considered to be safe during pregnancy.
 World Health Organizations technical report supports
that ultrasound is harmless.

25. THANK YOU