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Therapeutic Equipments Laser Therapy
Application Technique for Lasers Therapy
Categories of lasers according to the lasing medium
1) Solid laser (neodymium-YAG (Yttrium Aluminum Garnet), ruby, Diode) a
solid laser has several uses in the medical and scientific fields. And also used
in lower energy as (pointer) and in children's toys
2) Gas laser (He Ne, CO2, and Argon) has many uses in the industrial and military
fields where generate with very high energy. Argon (Ar)a gas laser of noble
gases and is used in the field of ophthalmology and there are many other types
3( Liquid laser (Rhodamine G6) - Organic dyes as a lasing medium
4) Chemical – extremely high powered, frequently used for military purposes Types of laser in medicine
Lasers are of three types:-
1. The power laser is used for destructive or surgical purposes.
2. Soft lasers have a very superficial effect and are used principally for treating the skin.
3. Mid laser is the type used by physiotherapists as their depth of penetration is
sufficient to produce a biological effect on deeper tissues without damaging them.
Technique of application
1. The wearing of protective glasses by the therapist and patient; 2. Working in a well-lit room; 3. Ra'aed Alobaidi
Avoiding reflect surfaces with the beam (mirrors, polished floors, chrome plating, etc.).
4. There is a slight problem with the accumulation of static electric charge by the
therapist with the hand held unit .This is more easily dissipated by operators
wearing non-insulating footwear and washing their hands at the end of treatment.
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Therapeutic Equipments Laser Therapy
5. Calculation of the laser dose
• The incident dose is measured as either POWER DENSITY or ENERGY DENSITY.
• Power density is given in watts per centimeter squared (W/cm2). It is usually in
the region of 50 W/ cm2 or less.
• Power density (W/cm2) = mean power (W) Surface area (cm2)
• Energy density given in joules per centimeter squared (J/cm2).
• Energy density (J/cm2) = mean power (W) X time(min) Surface area (cm2)
• There is wide variation in the recommendations for the optimal energy for
different conditions the usual ranges are from 1 to 10 J/cm2, but doses as low as
0.5 J/cm2 and up to 32 J/cm2 have been suggested.
• Higher doses are usually recommended for subcutaneous tissues.
• The most commonly used range for the dose is from 0.5: 4 J/cm2.
6. Contact techniques laser is applied using two main techniques:
a( Contact technique this technique for the optimum laser treatment using diode
systems (handheld probe) the tip of the probe is held perpendicular in contact of
the skin. This technique allows deeper penetration of laser and maximizes the
power density on the target tissues as reflection is minimized. b) Ra'aed Alobaidi
Non-contact technique this technique is used in the treatment of open wounds.
The distance between the laser probe and wound bed should be 0.5-1 cm. The
probe also should be held perpendicular to the site of radiation
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Therapeutic Equipments Laser Therapy
7. Method of application laser therapy a. Point application
• It is used to irradiate localized painful spots. Using the handheld probe, one can
use the contact and non-contact technique. It is commonly used in the treatment
of localized painful site, trigger points, and acupuncture points. b. Scanning application
• Scanning technique is used for the treatment of large areas, especially in wound healing.
• This technique the laser beam is automatically scanned across a predefined area.
Automatic scanning allows the easy uniform simple
application of laser treatment over a large area
instead of using manual scanning
• Usually used in case of wound healing. When the
laser machine is not offered with automatic scanners, manual scanning is
applied using a single handheld probe (non-contact). This technique is achieved
by the motion of the operator’s hand. Considerable care is required to ensure
that a reasonably uniform dosage is delivered to all wound area.
c. Gridding application: A more practical and less time consuming alternative
method to manual scanning for treating wounds. For this, the area of the wound
bed is visualized as being covered with a grid work of squares measuring 1cm X 1 Ra'aed Alobaidi cm. Apply to each square is systematically treated with a single diode probe. 8. Dosage :
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Therapeutic Equipments Laser Therapy
Amount of energy applied per unit area Measured in Joules/square cm (J/cm2).
Joule – unit of energy (1 Joule = 1 W/sec), Dosage is dependent on:
The output of laser in mW Time of exposure in seconds. Beam surface area of laser
in cm2Various dosage ranges per site (1-9 J/cm2)
9. Duration and frequency of treatment
The duration of treatment is determined according to the power of the laser unit.
For example, if the laser unit has 30 mW power to irradiate each cm2 with 1.5
J/cm2 each square is irradiated for 50sec. Laser treatment is given once daily or on alternate days T A = (E / Pav ) × A
T A = treatment time for a given area
E = mJ of energy per cm 2
P av = Average laser power in mW A = beam area in cm 2 E =1.5 P av = 0.003 A = 0.1
T A = (1.5 / 0.003) × 0.1 T A =50 sec Or Ra'aed Alobaidi
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