Ultraviolet Radiation Therapy: Procedures and Indications

Definition of Ultraviolet Radiation (UVR)

UVR (Ultraviolet Radiation) refers to a type of electromagnetic radiation with a wavelength shorter than visible light but longer than X-rays, typically ranging from 100 to 400 nanometers (nm). It is divided into three main categories:

• UVA (315–400 nm): Least harmful, penetrates deeper into the skin.
• UVB (280–315 nm): Causes sunburn, has more energy, and is more harmful to the skin.
• UVC (100–280 nm): Most dangerous but absorbed by the Earth's atmosphere and does not reach the surface.

In therapeutic and physiotherapy contexts, UVR is used in ultraviolet therapy, also known as phototherapy, primarily for skin conditions.

Procedure of UVR Therapy

1. Preparation
   • The area to be treated is cleaned and exposed.
   • Protective goggles are provided to the patient and therapist to avoid eye damage.
   • Skin type is assessed (Fitzpatrick scale) to determine dosage.
2. Test Dose (Minimal Erythemal Dose - MED) Determination
   • A small patch of skin is exposed to UVR for different time intervals.
   • The MED is the smallest dose that causes redness (erythema) after 24 hours.
   • This helps in individualizing treatment dosage.
3. Application
   • Based on the MED, the treatment dose is calculated.
   • UVR is applied using a mercury vapor lamp or UV therapy unit at a specific distance and time.
   • Treatment usually begins with a sub-erythemal dose and is gradually increased.
4. Post-Treatment Care
   • Skin is observed for any adverse reactions.
   • Moisturizer may be applied to the treated area.
   • The patient is advised to avoid sun exposure post-treatment.

Indications for UVR Therapy

UVR is mainly indicated for dermatological and certain infectious conditions, including:

• Psoriasis
• Eczema (Atopic Dermatitis)
• Acne Vulgaris
• Vitiligo
• Chronic wounds and ulcers
• Pressure sores (bedsores)
• Fungal infections
• Bacterial skin infections (e.g., MRSA)
• Rickets and Vitamin D deficiency (in rare cases, UVC or artificial sunlight may be used)

Contraindications

• Skin cancer or precancerous lesions
• Lupus erythematosus
• Active tuberculosis
• Acute eczema or dermatitis
• Photosensitivity disorders or medication-induced photosensitivity
• Severe cardiovascular conditions