THERAPEUTIC ULTRASOUND: A PRACTICAL APPROACH BY MINED ACADEMY

1. THERAPUTIC ULTRASOUND
A CLINICAL APPROACH
DR. SRIMOYEE ROY (PT)
PHYSIOTHERAPIST
IMS & SUM HOAPITAL,
SOA UNIVERSITY.

2. TYPES OF ULTRASOUND
1) Diagnostic ultrasound – basically
used for the imaging fetus during
pregnancy, view different visceral
organs, soft tissue.
* High frequency 7-18 MHz
2) Therapeutic ultrasound –used for
treatment/ healing purpose.
* frequency of 0.5 - 5 MHz

3. ULTRASOUND APPARATUS-

4. Productionof ultrasonicwave
 This ultrasonic wave
produced is longitudinal
wave form , in a
compression-
rarefaction manner .
 When the crystal
expands, it compresses
the material in front of it,
and when it contracts, it
rarefies the material in
front of it.

5. CAVITATION
 During the compression phase
of an ultrasound wave, bubbles
present in the tissue are made
smaller, and during the
rarefaction phase, they expand.
 Cavitation may be stable or
unstable.
 stable cavitation-
nonthermal effect.
 unstable cavitation- gives
thermal effect.

6.  3mhz frequency ultrasound has
1-2 cm depth of penetration, but
the temperature increase is
higher.
 The 1mhz frequency ultrasound
is best for heating tissues up to
5cm deep.
ERA- effective radiating area

7. Coupling media

8. METHORD OF APPLICATION-

9. DIRECT CONTACT WATER BAG METHORD
WATER BATH METHORD

10. TREATMENT PARAMETERS
Mode- continues - thermal effect where as pulsed -non
thermal effect
Frequency
 -1 MHz is used For tissue up to 5 cm deep
 3 MHz is used for tissue 1 to 2 cm deep.
Duty Cycle
 When the goal is to increase tissue temperature - 100%
duty cycle should be used.
 When ultrasound is applied only for nonthermal -20%
or lower duty cycle is used.
Intensity -
 In 1 MHz-an intensity of 1.5 to 2.0 W/cm2 is used .
 In 3 MHz - about 0.5 W/cm2 intensity is generally
sufficient.

11. Duration
 In general the ratio is followed-
2-3min – 2 cm2
diameter of 1 ERA is treat for 2mins
 For chronic-longer treatment time
 For acute – shorter treatment time
 To facilitate fracture healing longer treatment
duration is recommended i.e 15-20 mins.

12. EFFECTS OT ULTRASOUND
 Ultrasound has a variety of biophysical effects.
 Two type – thermal effect and non thermal effect.
1) THERMAL EFFECTS
Changes in tissue level-
❑ Acceleration of metabolic rate.
❑ Reduction or control of pain .
❑ Reduces muscle spasm.
❑ Alteration of nerve conduction velocity.
❑ Increased circulation.
❑ Increased soft tissue extensibility

13. Tissue’sabsorption coefficients –
 Absorption coefficient (AC): The degree at which a
material absorbs ultrasound waves.
 Tissues with high collagen content trend to have high
absorption coefficient, and tissues with high water content
generally have low absorption coefficients .
 Thus ultrasound is particularly well suited to heating
tendons, ligaments, joint capsules, and fasciae.
 ultrasound can be very effective for heating small areas of
scar tissue in muscle that will likely absorb more
ultrasound because of their increased collagen content.

15. 2. NONTHERMAL EFFECT-
 When ultrasound is delivered in a pulsed mode, with a
20% of duty cycle, heat generated during the on time of
the cycle is dispersed during the off time, resulting in
no measurable net increase in temperature.
 The intracellular calcium levels .
 skin and cell membrane permeability.
 mast cell degranulationand the release of histamine.
 Ultrasound also promotes macrophage responsiveness
and increases the rate of protein synthesis by fibroblasts
and tendon cells
 low intensity ultrasound increases nitric oxide synthesis
in endothelial cells and increases blood flow when
appliedto fractures bones .

16. CLINICAL APPLICATIONS
OF
ULTRASOUND

17. 1) Soft tissueshortening
 Soft tissue shortening can be the result of immobilization, inactivity,
or scarring and can cause joint range of motion restrictions, pain,
and functional limitations.
 Increasing the temperature of soft tissue increases its extensibility
property as ultrasound can penetrate to the depth.
 Joint capsules, tendons, and ligament these tissues have high
ultrasound absorption coefficients.
 The deep heating produced by 1 MHz continuous ultrasound at 1.0 to 2.5
W/cm2 intensity has been shown to be more effective.

18. 2) Pain control
 The ultrasound waves shows a good result in stimulation of
the cutaneous thermal receptors as compared to other
superficial heating agents like paraffin wax, IR.
 The changes in nerve conduction velocity also has effect on
reduction of pain.
 The nonthermal effects of ultrasound helps in
modulations of inflammation by nonthermal effects of
ultrasound.
 Studies show that Continuous ultrasound at 0.5 to 2.0
W/cm2 intensity and 1.5 MHz frequency is more effective
than superficial heating agents like paraffin ,IR.

19. 3) Dermal ulcers and Surgical skin incisions
 Some studies have shown that ultrasound accelerates
the healing of vascular and pressure ulcers.
 Pulsed Ultrasound at 20% duty cycle, 1.0 W/cm2
intensity, 3 MHz frequency, for 5 to 10 minutes.
 Ultrasound is applied around the periwound area in
case of dermal ulcer or surgical skin incisions or the
wound can be treated directly by covering it with an
ultrasound coupling sheet.

20. 4) Tendon and ligament injuries
 While treating any acute injuries we should use
nonthermal effect i.e(pulsed mode with a 20% duty
cycle, 1.0 to 2.0 W/cm2 intensity, 1 MHz frequency,
for 5 to 10 minutes) because any raise in tissue
temperature can aggravate inflammation.
 Lately in chronic stage or recovery stage we can go
with continues mode to have a thermal effect and
facilitate healing.
 Apart of reducing inflammation and facilitating
healing it also contributes in reduction of pain.

21. 5)Bone fracture
 As we already studied bone has the maximum
absorption coefficients
 Current research supports the use of very low-dose
ultrasound for facilitation
of fracture healing.
 The parameters found to
be effective are pulse mode
1.5 MHz frequency,
0.1 W/cm2 intensity,
20% duty cycle,
for 15 to 20 minutes daily.

22.  6) phonophorosis
 Phonophoresis is the application of ultrasound along
with a topical drug like corticosteroids and NSAIDs
to treat tissue inflammation associated with
conditions such as tendinitis or bursitis, ultrasound is
intended to enhance delivery of the drug through the
skin, for local or systemic effects.
 Transcutaneous drug delivery has a number of
advantages over oral drug administration. It provides
a higher initial drug concentration at the delivery
site, avoiding the liver.
 Transcutaneous delivery also avoids the pain, trauma,
and infection risk associated with injection and
allows delivery to a larger area than that is achieved
by injection.

24. CONTRA-INDICATIONS
 Malignant tumor
 Pregnancy
 Central nervous system (CNS) tissue.
 Plastic or Joint cement
 Pacemaker
 Thrombophlebitis
 Reproductiveorgans

25. ADVERSE EFFECT OF ULTRASOUND
 ultrasound when applied incorrectly ,or when
contraindicated can have adverse effect.
 The most common adverse effect is a burn, which may
occur when high-intensity, continuous ultrasound is
applied, particularly if the head is not movied.
 The risk of burns is further increased in areas with
impaired circulation or sensation and with superficial
bone.
 To minimize the risk of burning a patient,therapist
always move the ultrasound head.
 Reduce the ultrasound intensity in areas with superficial
bone, or if the patient complains of any increase in
discomfort with the application of ultrasound.

26.  Ultrasound standing waves can cause blood cell stasis
because of collections of gas bubbles or cavitation.
 This is accompanied by damage to the endothelial lining of
the blood vessels.
 Although the stasis is reversed when ultrasound
application stops, endothelial damage remains.
 Another concern is the possibility of cross-
contamination and infection of patients. The transducer
heads were generally contaminated with bacteria
(Staphylococcus)normallyfound on the skin.

27. QUICK REVIEW
ON
CLINICAL DECISION MAKING
OF
ULTRASOUND PARAMETERS

28. 2mins×ERA