PHYSMOD_UVR

This is shorter than visible light but longer than x-rays; 400-200 nm

UVR

UVR

Freq:

Wavelength:

Freq : 1.65 × 10^15 to 7.5 ×10^14 Hz

Wavelength: shorter than visible light but longer than x-rays

BANDS→ WAVELENGTH→ OTHER NAME → USE

1. UVA → ________ nm →______ UV → _______

2. UVB → ________ nm →______ UV →________

3. UVC → ________ nm → ______ UV →______

1. UVA → (315) 320-400 nm →Long-wave UV; Near UV → blacklight

2. UVB → (280) 290-320 nm →Middle-wave UV →skin erythema; sunburn

3. UVC → (200) < 100-290 nm → Short-wave UV →germicidal; bactericidal

UVR characteristics

• Method of transmission: __________

• Reflected, refracted, and absorbed 

  • Absorbed within the first ___ mm (0.22 mm) of human skin 

  • ___% absorbed in the dermis

• _________ property - causes chemical changes or metabolism of superficial skin tissues (closer to visible light = longer wavelengths) 

  • Used for physiologic effects like electron excitation 

• _________ property - primarily harmful; x-ray; can cause gene mutation, harmful to DNA  (closer to x-ray, shorter wavelength)

  
  

• Radiation (Phototherapy)

• 1-2mm of human skin

• 80-90% absorbed in dermis

• Non-ionizing; Ionizing 💢

Phototherapy

• Excessive natural UVR exposure → DNA damage

  • Cutaneous _____ melanoma

  • _____-cell carcinoma

  • ______-cell carcinoma

• Excessive natural UVR exposure → DNA damage

  • Cutaneous malignant melanoma

  • Vasal-cell carcinoma

  • Squamous-cell carcinoma

Factors Affecting UV Penetration (read)

• Intensity of radiation 

• Wavelength of radiation 

• Power of radiation source 

• Exposure duration 

• Distance of radiation source 

• Frequency 

• Size of area 

• Thickness of skin 

• Pigmentation of skin

Pigmentation

• Presence of melanin affects penetration

  • INC/DEC? melanin on skin = ↑ barrier to penetration = ↑ protection

INC ( darker the better)

UVR Equipments

• _______________

  • Small

  • Emit radiation at constant intensity

  • Used for smaller areas

  • Hot Quartz or Cold Quartz

  • For localized application

Mercury Arc Lamps

Mercury Arc Lamps

1. ______________

   1. Burner (argon gas and mercury)

   2. ↑ pressure and temperature

   3. (+) erythema and pigmentation

   4. Applied ____ from the area

   5. Needs warm up ?

Hot Quartz

• ≥15” from area

• NO warm up

Mercury Arc Lamps

2. _________

   1. Quartz tube with mercury (ionized vapor) 

   2. ↓ pressure and temperature 

   3. Minimal erythema and (-) pigmentation 

   4. Application at close proximity (____ inches) 

   5. Needs 5 _____ warm-up

2. Cold Quartz

   1. 1-2 inches

   2. needs 5 min warm up

UVR Equipments

2. Fluorescent Lamps

   1. Long 

   2. Emit ____-intensity radiation 

   3. Used for ____ areas 

   4. Low pressure mercury discharge tubes with phosphor coating inside (_______) 

• Higher intensity radiation

• larger areas

• Theraktin

Physiologic Effects of UVR

1. Erythema Production

   1. Dilation of blood vessels due to ______ release 

   2. Exposure to ____ or _____ after drug sensitization 

   3. Skin Redness - _________ release 

1. Dilation of blood vessels due to histamine release 

2. Exposure to UVB or UVA after drug sensitization 

3. Skin Redness - prostaglandin release 

Physiologic Effects of UVR

2. Tanning

   1. Delayed _____ of the skin

   2. Due to exposure

   3. Increased production and upward migration of _____ granules and oxidation of _______

   4. Skin color affects penetration of UV (Tanning = ↓ penetration)

   5. ↑ tan = ↑ protection

Fluorescent and hot quartz can both cause tanning or pigmentation

1. Delayed pigmentation of the skin

2. Due to exposure

3. Increased production and upward migration of melanin granules

   and oxidation of premelanin

4. Skin color affects penetration of UV (Tanning = ↓ penetration)

5. ↑ tan = ↑ protection

Fluorescent and hot quartz can both cause tanning or pigmentation

Physiologic Effects of UVR

3. Epidermal Hyperplasia

   1. Thickening of ______ layer of skin

   2. Thickening of _______ (stratum corneum) due to cell proliferation

   3. Occurs usually after _____ hours after exposure to UVR

1. Thickening of superficial layer of skin

2. Thickening of eipdermis (stratum corneum) due to cell proliferation

3. Occurs usually after 72 hours after exposure to UVR

Physiologic Effects of UVR

4. Vitamin D Synthesis

   1. Coverts ingested provitamin D to _________

      1. Found to be an effective treatment for ______

1. Coverts ingested provitamin D to active Vitamin D 

   1. Found to be an effective treatment for psoriasis

Physiologic Effects of UVR

5. Bacterial Effect

   1. ____ = bactericidal 

      • Also promotes _____ healing 

      • _______ = slough off (shed off) dead skin cells 

UVA & UVB =_______/______

1. UVC = bectericidal 

   • Also promotes wound healing 

   • Desquamation = slough off (shed off) dead skin cells 

UVA & UVB = redness or sunburn

UVR VS IRR

UVR

• _______ effect

• No _____

• Absorbed at _____ mm

• _____ source

• Delayed ______ (dark)

• Lasts for ______ days

• Has _____ wavelength (more superficial)

• Photochemical effect

• No heat

• Absorbed at 1-2 mm

• Luminous source

• Delayed erythema (dark)

• Lasts for several days

• Has shorter wavelength (more suiperficial)

UVR VS IRR

Infrared

• ______ Effect

• Absorbed as _____

• Absorbed at ___ mm

• ______ and _______

• Immediate _____ (light)

• Lasts for ___- ____ mins

• Has _____ wavelength (deeper penetration)

Infrared

• Physical Effect

• Absorbed as heat

• Absorbed at 3 mm

• Luminous and non-luminous

• Immediate erythema (light)

• Lasts for 20-30 mins

• Has longer wavelength (deeper penetration)

Dosimetry

Parameter → Synonym → Formula → Unit

• Irradiance (I) → Intensity /Power → ________ → _______

• Exposure Duration T → Treatment time → NA → ______

• Dose per Treatment(D1) → Amount of energy delivered to skin for a single treatment →_______ → ______

• Cumulative Dose (Dc) → Summation of all doses →______ → ______

• Irradiance (I) → Intensity or power → Measured by UV sensor on device → mw/cm2

• Exposure Duration T → Treatment Time → NA → sec

• Dose per Treatment(D1) → Amount of energy delivered to skin for a single treatment → Dt = I x T → mJ/cm2

• Cumulative Dose (Dc) → Summation of all doses → Dc=EDt → J/cm2

_______ Law

• Inverse relationship of irradiance and exposure time

Bunsen-Roscoe Law / Reciprocity Law

Fitzpatrick Skin Phototype Method

• ____________ Method

  • More convenient to use; based on skin color and reaction to sun exposure

Fitzpatrick Skin Phototype Method

Fitzpatrick Scale

• 1 → _____ white → ____ easily; never ___

• 2 → ____ white → burns ____; tans _____

• 3 → ____ brown → burns ____ ; tans _____

• 4 → ____ brown → burns ____ ; tans ____

• 5 → ____ brown → burns ____ ; tans _____

• 6 → _____ → burns ____ ;intense _____

• 1 → Lighter white → burns easily; never tans

• 2 → Darker white → burns easily ;tans minimally

• 3 → Light brown → burns mod; tans gradually

• 4 → Moderate brown → burns min; tans well

• 5 → Dark brown → burns rarely; tans profusely

• 6 → Black →never burns; intense tanning

Recommended UV Dosing based on Skin Phototype

Treatment Freq → _____ per week

3-5 treatments per week

______________

• UV-induced Erythema - varies on each individual

• Dose of UV radiation that will produce a barely detectable erythema about 8-24 hours after exposure

Minimal Erythemal Dose Method

Minimal Erythemal Dose Method : Dose-Response Assessment

• Suberythemal Dose (SED)

• __________ (MED)

• First Degree Erythema (E1)

• Second Degree Erythema (E2)

• Third Degree Erythema (E3)

______ is the target effect

REMEMBER: to instruct the patient to observe which shape appears last but disappears first (Erythrometer, 15s increments)

Minimal Erythemal Dose

Minimal Erythemal Dose Method

Minimal Erythemal Dose Method

Minimal Erythemal Dose Method

Guidelines in Altering Intensity

For Cold Quartz (Kromayer Lamp), the lamp is applied at least ____ inch away from the wound

For Hot Quartz lamp, the lamp is is initially applied ___-___ cm distance 

Distance is altered when duration has reached the maximum ___ minutes 

• at least 1 inch away

• 60-80cm distance

• 5 minutes

Contraindications

Over the eyes  Skin Cancer  Pulmonary Tuberculosis  Cardiac, Kidney or Liver Disease  Systemic Lupus Erythematosus  Fever  Taking birth control pills

Precautions

• Photosensitivity or Photoallergy 

• Photosensitizing Medications 

• Recent x-ray therapy 

• No dose of UV should be done until the effects of the previous treatmernt have disappeared 

Indications

1. Subacute and Chronic Psoriasis

   1. Narrow-Band UVB (NBUVB) 

      • ___ or E__

      • Also for _____ 

   2. PUVA (Psoralen + UVA) 

      • Usually, E__ is used 

      • E2 for ____ and ____

      Also used for: 

      • Eczema 

      • Urticaria 

      • Cutaneous T-cell lymphoma 

      • Some photosensitive disorders

1. Narrow-Band UVB (NBUVB) 

   • MED or E1 

   • Also for vitiligo 

2. PUVA (Psoralen + UVA) 

   • Usually, E1 is used 

   • E2 for heels and elbows

   Also used for: 

   • Eczema 

   • Urticaria 

   • Cutaneous T-cell lymphoma 

   • Some photosensitive disorders

Indications

2. Cystic Acne/Acne Vulgaris

   1. E1 for ___, ____ and ____

   2. E2 for ____ and ____

2. Cystic Acne/Acne Vulgaris

   1. E1 for face, neck and chest

   2. E2 for back and shoulders

Indications

3. Non-Infected Open Wounds

   1. Such as surgical incisions, pressure/ venous/ arterial ulcers

   2. Use UV___

   3. Granulation Tissue = no treatment or suberythemal dose to ____ only, no progression

   4. Decubitus Ulcers = affecting the epidermis/dermis: __/_

   5. Surrounding skin = _____, daily

3. Non-Infected Open Wounds

   1. Such as surgical incisions, pressure/ venous/ arterial ulcers

   2. Use UVC

   3. Granulation Tissue = no treatment or suberythemal dose to MED only, no progression

   4. Decubitus Ulcers = affecting the epidermis/dermis: E1/E2

   5. Surrounding skin = MED, daily

4. Infected Open Wounds

   1. Thin yellowing slough = ____ daily and unprogressed

   2. Definite green or yellow slough = ___ daily and unprogressed

   3. Black Slough = __ daily

   4. Surrounding skin = ____ daily

1. Thin yellowing slough = E2 daily and unprogressed

2. Definite green or yellow slough = E3 daily and unprogressed

3. Black Slough = E3 daily

4. Surrounding skin = MED daily

Other Indications

• Counter-irritation for pain relief (____ applied that the discomfort masks the pain)

• Alopecia - UV__ at __ or _

• Vitamin D deficiency

• Uremic pruritus - ___ UV__

• Counter-irritation for pain relief (E3 applied that the discomfort masks the pain)

• Alopecia - UVB at E1 or E2

• Vitamin D deficiency

• Uremic pruritus - SED UVB

PRECAUTIONS

Photosensitizing Medications

• _________ = sensitizing agent 

• Sulphonamides & Tetracyclines = ___ 

• Griseofulvin = ________ 

• Phenothiazine = _______ 

• ________ = diuretic

Psoralen = must stay away from the sun because it can cause hyperpigmentation (increases light penetration)

• Psoralen = sensitizing agent 

• Sulphonamides & Tetracyclines = antibiotics 

• Griseofulvin = antifungal 

• Phenothiazine = tranquilizer 

• Chlorothiazide = diuretic

Adverse Effects

• Burning

• Premature aging of skin (actinic damage) 

• Carcinogenesis 

• Eye damage (photokeratitis, conjunctivitis, cataracts)

Documentation

TBD

UV Overdose

• IRR for 20 mins every hour for 6-8 hrs

Documentation for Overdose

• Date 

• Lamp used 

• Distance 

• Exact area treated (specify pt position) 

• Time 

• Reaction obtained

Treatment Considerations

• Phototesting for the determination of MED 

  • Time of appearance (last to appear) 

  • Time of disappearance (first to disappear) 

• Characteristics/description 

• Calculation of dosage 

• Area of application 

• Progression

Steps in Determining Dosage

Trivia:

Define the word “racist”

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