Lasers, UV Radiation Flashcards
The clinical effects of EM Radiation are determined by = ?
FWI
Lasers, UV Radiation
The nature of the clinical effects of EM Radiation are determined by:
- Frequency
- Wavelength range of the radiation
- Intensity of the radiation
- Examples of low frequency EM radiation include = ?
- Examples of high frequency EM radiation = ?
Lasers, UV Radiation
Low Frequency EM Radiation:
- Extremely low-frequency waves (ELF)
- Shortwaves
- Microwaves
- IR radiation
- Visible light
- Ultraviolet A and B (UVA, UVB)
- Nonionizing; cannot break molecular bonds or produce ions
- Can be used for therapeutic medical applications
High Frequency EM Radiation:
- X-rays, gamma rays
- Ionizing, can break molecular bonds to form ions
- Can inhibit cell division
- Used for imaging or tissue destruction
Intensity of EM Radiation:
Intensity of EM is greatest when = ?
3 things…
Lasers, UV Radiation
Intensity is greatest when =
- Energy output is high
- Radiation source is close to the patient
- Beam is perpendicular to the surface of the skin
Clinical Use of EM Radiation:
IR radiation produces = ?
Lasers, UV Radiation
Clinical Use of EM Radiation:
- IR radiation produces superficial heating.
Clinical Use of EM Radiation:
UV radiation produces = ?
Lasers, UV Radiation
UV radiation produces:
- Erythema
- Tanning
- Epidermal hyperplasia
Clinical Use of EM Radiation:
Shortwave and microwave radiation are used to heat = ?
Lasers, UV Radiation
Shortwave and microwave radiation = Used to heat deep tissues, decrease pain, decrease edema, facilitate tissue healing
Clinical Use of EM Radiation:
Low-intensity laser are used to promote = ?
Lasers, UV Radiation
Low-intensity laser – Used to promote tissue healing, control pain and inflammation
Physiological Effects of EM Radiation
Arndt-Shulz Law = ?
Lasers, UV Radiation
- Minimal stimulus needed to initiate biological process.
- Too strong may be inhibitory.
Laser = ?
Think L.A.S.E.R
Lasers, UV Radiation
Laser = Light Amplification by Stimulated Emission of Radiation.
Laser light can be = ?
Lasers, UV Radiation
Laser light:
- Monochromatic
- Coherent
- Directional
What source of light?
High-intensity light in one area = ?
Lasers, UV Radiation
Laser diodes:
- Each producing light in the visible or IR range of the EM spectrum.
- Many applicators include a few laser diodes, SLDs and LEDs together in a cluster (10-20 diodes).
- High-intensity light in one area
Sources of light:
LEDs produce = ?
Lasers, UV Radiation
LEDs (Light emitting diodes) produce:
- Low-intensity, non-coherent, non-monochromatic, non-directional light that may appear to be one color and spreads widely.
Sources of light:
SLDs produce =?
Lasers, UV Radiation
SLDs (Supraluminous diodes) produce:
- High-intensity, almost monochromatic light
- Not coherent
- Require shorter application than LEDs
- Deliver energy to a wider area than laser
Laser
Three sources of light = ?
Lasers, UV Radiation
Laser - Sources of light:
- LEDs (Light emitting diodes)
- SLDs (Supraluminous diodes)
- Laser diodes
High power lasers are used for = ?
scope…
Lasers, UV Radiation
High power - AKA “hot” lasers:
- Surgical cutting and coagulation
- Ophthalmologic
- Dermatologic
- Oncologic
- Vascular
Lower power lasers are used for = ?
Lasers, UV Radiation
Low-level laser therapy (LLLT) - AKA low-power laser, “cold” or “soft” laser:
- Treatment of tendon or ligament injury
- Arthritis
- Lymphedema
- Soft-tissue healing
- Bone healing
- Neurological conditions
- Pain management
Wavelength
- Longer wavelength = ?
- Shorter wavelength = ?
Lasers, UV Radiation
Wavelength:
- Optimal depth of penetration is 600-1300 nm (red or IR).
- Longer wavelength = Lower frequency = Penetrates deeper.
- Shorter wavelength = Higher frequency = Penetrates less deeply.
- IR penetrates 2-4 cm into soft tissue
- Red light penetrates only a few mm, just through and below the skin.
Power and Power Density
Most laser diodes used for therapy ( class 3B ) have a power between = ?
Lasers, UV Radiation
Power and Power Density:
- Power = Rate of energy flow.
- Power Density = Amount of power per unit area.
- Class 3B
- Most laser diodes used for therapyhave a power between 5-500mW.
Energy and Energy Density
- Energy formula = ?
- Energy density = ?
Lasers, UV Radiation
Energy (J) = Power (W) x Time (s)
- Since energy includes time, the clinician using a laser light therapy device generally does not need to select (or document) the treatment time.
Energy Density = Amount of power per unit area
- Measured in J/cm2
- The treatment dose
- J/cm2 = Energy (J) / area of irradiation (cm2)
Effects of lasers and light include = ?
stimulates, promotes, alters, and initiates…
Lasers, UV Radiation
Effects of Lasers and Light:
- Stimulates ATP , and RNA production.
- Alters the synthesis of cytokines (inflammation), nerve conduction velocity, and regeneration
- Inhibit bacterial growth
- Promote vasodilation
- Initiates reactions at the cell membrane by affecting calcium channels and intercellular communication.
Contraindications for lasers = ?
Lasers, UV Radiation
Contraindications for Lasers:
- Malignancy
- Direct irradiation of the eyes
- Within 4-6 months of radiotherapy
- Hemorrhaging regions
- Over thyroid or other endocrine glands
Precautions for lasers include = ?
Lasers, UV Radiation
Precautions for Lasers:
- Low back or abdomen during pregnancy
- Epiphyseal plates in children
- Impaired sensation
- Impaired mentation
- Photophobia = Abnormal sensitivity to light, especially of the eyes
- Abnormally high sensitivity to light
- Pretreatment with one or more photosensitizers
- Medications that increase a patient’s sensitivity to light (have you ever been on antibiotics that warn you to wear sunscreen when out in the sun?).
Adverse effects of lasers and light include = ?
Lasers, UV Radiation
Adverse Effects of Lasers and Light:
- Transient tingling
- Mild erythema
- Skin rash
- Burning sensation
- Adverse effects from irradiation of the eyes
Laser Protocol
- Clear of _ ? _
- _ ? _ the skin
- Clinician & patient wear _ ? _
- Keep applicator _ ? _ to skin
- Do not _ ? _ during application
- Apply with _ ? _
Lasers, UV Radiation
Protocol:
- Clear of contraindications and indications
- Clean the skin
- Clinician and Patient wear protective eyewear
- Keep applicator perpendicular to skin
- Do not move during application
- Apply with firm pressure if not contraindicated
Parameters - Lasers & Light:
- Laser wavelength = ?
- Red wavelength = ?
- Near-IR wavelength = ?
Lasers, UV Radiation
Wavelength:
- Laser =
- 500 – 1100 nm
- Red =
- 600 – 700 nm
- Better for treating superficial tissues (5-10 mm)
- Near-IR =
- 700 - 1100 nm
- Longer wavelength
- Penetrates deeper (30-40 mm)
Power:
- Class 1 to class 4
- Clinically used at 3B (5 - 500 mW)
Scanning, gridding, and wanding are examples of = ?
Lasers, UV Radiation
Laser Treatment Techniques:
- Laser tip should be in light contact with skin.
- Directed perpendicularly to the target tissue.
- Gridding – imaginary grid with 1 cm squares.
- Scanning – no contact between laser tip and the skin.
- Wanding – uses oscillatory technique over a grid area.
What should be documented = ?
Lasers, UV Radiation
Documentation:
- Type of diode (laser, LED, SLD)
- Wavelength (nm)
- Power (mW)
- Area of the body treated
- Energy density (J/cm2)
- Patient’s reaction to treatment
Physical Properties of UV Radiation
- UVA = ? nm
- UVB = ? nm
- UVC = ? nm
Lasers, UV Radiation
- Divided into three bands:
- UVA = 320-400 nm
- UVB = 290-320 nm
- UVC = < 290 nm
Physical Properties of UV Radiation
- UVA = ?
- UVB = ?
- UVC = ?
what wavelength (short or long)
Lasers, UV Radiation
Physical Properties of Ultraviolet Radiation:
- UVA
- Aka long-wave UV
- Non-ionizing
- Produces fluorescence
- UVB
- Middle-wave UV
- Non-ionizing
- Produces the most skin erythema
- UVC (filtered out by the ozone layer)
- Shortwave
- IONIZING
- Germicidal
Effects of UV radiation include = ?
Lasers, UV Radiation
Effects of Ultraviolet Radiation:
- Erythema production
- Tanning
- Epidermal hyperplasia
- Vitamin D synthesis
- Other effects:
- Bactericidal
- Suppression of immune response w/ low doses
- Activation of immune response w/ high doses
- Wound Healing
- Enhances epithelialization
- Destroys bacteria
- Absorbed equally by all skin colors
- Erythema is redness of the skin caused by injury or another inflammation-causing condition.
Precautions for UV include = ?
everything photo…
Lasers, UV Radiation
Precautions for UV:
- Photosensitizing medications
- Photosensitizing supplements
- Photosensitivity
- Patients with fair skin and hair color, those w/ red hair have greater risk to UV exposure.
- Recent X-ray therapy
- No dose should be repeated until the effects of the previous dose have disappeared.
Contraindications for UV = ?
Lasers, UV Radiation
Contraindications for UV:
- Irradiation of the eyes
- Skin Cancer
- Pulmonary Tuberculosis
- Cardiac, kidney or liver disease
- Systemic Lupus Erythematosus
- Fever
What is UV used to treat = ?
Lasers, UV Radiation
Clinical Indications for use of UV:
- Skin conditions:
- Psoriasis
- Scleroderma
- Eczema
- Atopic dermatitis
- Cutaneous T-cell lymphoma
- Vitiligo
- Palmaplantar pustulosis
- Treatments:
UVB or PUVA
- Recent study of the use of UVA in conjunction with Psoralen-based topical and systemic drugs.
- Psoralen is a light-sensitive drug that absorbs UVA light and acts like UV radiation.
- Psoralens are taken orally or applied topically, with UVA light for treatment.
Adverse Effects of UV Radiation = ?
Adverse Effects of UV Radiation:
- Burning
- Premature aging of the skin
- Carcinogenesis
- Eye damage
Determining the minimal erythemal dose can be affected by = ?
Determining the Minimal Erythemal Dose:
- Determine the patient’s sensitivity to UV radiation.
- Varies widely
- Affected by:
- Skin pigmentation
- Age
- Prior exposure to UV
- Type of UV
- Use of sensitizing medications
- Use the same lamp for determining sensitivity and for treatment
Dose-response assessment:
- Suberythemal dose = ?
- Minimal erythemal dose = ?
- First-degree erythema = ?
- Second-degree erythema = ?
- Third-degree erythema = ?
Dose-Response Assessment:
- Suberythemal dose (SED):
- No change in skin redness occurs in the 24 hrs after UV exposure.
- Minimal erythemal dose (MED):
- The smallest dose produces erythema within 8 hrs after exposure that disappears within 24 hrs after exposure
- First-degree erythema (E1):
- Definite redness with some mild desquamation appears within 6 hrs after exposure and lasts for 1-3 days.
- This dose is generally 2.5 times the MED
- Second-degree erythema (E2):
- Intense erythema with edema, peeling, and pigmentation appears within 2 hrs after exposure and is like a severe sunburn.
- This dose is generally 5 times the MED
- Third-degree erythema (E3):
- Erythema with severe blistering, peeling and exudation. This dose is generally 10 times the MED.
UV
What should be included in the documentation = ?
Dose-response assessment:
Documentation - UV:
- If and how Psoralen was given
- Area of body treated
- Type of UV radiation used
- Serial number of the lamp
- Distance of the lamp from the patient
- Treatment duration
- Patient’s response to treatment
