Ultraviolet Radiation Flashcards
UV raidiation wavelength is from ___ nm to below ___nm
400 290
3 bands of UV radiation
UVA
UVB
UVC
UVA has a wavelength of ___-___nm
UVB has a wavelength of ___-___nm
UVC has a wavelength less than ___nm
320-400
290-320
290
What effect does UVA have on the skin? UVB? UVC?
UVA produces fluorescence
UVB produces the most skin erythema
UVC is germicidal (chronic open wounds)
When is UV radiation intensity at its greatest?
with high-powered lamp, close to patient, perpendicular to skin surface
5 Effects of Ultraviolet Radiation
- Erythema production
- Tanning
- Epidural hyperplasia
- Vitamin D synthesis
- Bactericidal
With ___ doses of UV radiation the immune responses is suppressed
low
With ___ doses of UV radiation the immune response is activated.
high
What skin conditions are indications for the use of UV radiation?
- Psoriasis
- Scleroderma
- Eczema
- Atopic dermatitis
- Cutaneous T-cell lymphoma
- Vitiligo
- Palmaplantar pustulosis
What band of UV radiation is most commonly used for the treatment of chronic open wounds?
UVC
How does UV help with wound healing?
It enhances epithelialization and destroys bacteria
6 Contraindications for UV
- Irradiation of the eyes
- Skin Cancer
- Pulmonary Tuberculosis
- Cardiac, kidney or liver disease
- Systemic Lupus Erythematosus
- Fever
5 Precautions for UV
- Photosensitizing medications
- Photosensitizing supplements
- Photosensitivity
- Recent X-ray therapy
- Too soon after previous dose
4 Adverse Effects of UV Radiation
- Burning
- Premature aging of the skin
- Carcinogenesis
- Eye damage
How do you determine a patient’s sensitivity to UV radiation?
Using a square grid pattern, expose different squares for extended periods of time
What are the 5 dose responses?
- Suberythemal dose (SED)
- Minimal erythemal dose (MED)
- First-degree erythema (E1)
- Second-degree erythema (E2)
- Third-degree erythema (E3)
Describe Suberythemal dose (SED)
There is no change in skin redness 24 hrs after UV exposure
Describe Minimal erythemal dose (MED)
The smallest dose producing erythema within 8 hrs after exposure that disappears within 24 hrs after exposure
Describe 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
Describe 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
Describe Third-degree erythema (E3)
Erythema with severe blistering, peeling and exudation. This dose is generally 10 times the MED
At which dosage should you treat your patient?
Minimal erythemal dose (MED)
