U L T R A V I O L E T - PowerPoint Presentation

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U L T R A V I O L E T

R A D I A T I O NSlide2

ULTRAVIOLET RADIATION (UVR)

Radiation between the visible light & X-ray sections of the electromagnetic spectrum. (J. Ritter)

VISIBLE LIGHT

IRR

UVR

RADIO

fSlide3

NATURE OF UVR

1. Strongly

absorbed in air (*short-wavelength

UVR)2. Behave like visible radiation in terms of properties (reflection, refraction, transmission and absorption)

3. Transmit more energy, thus, producing more chemical changes not just simply heatSlide4

CATEGORIES OF UVR

UVA

UVB

UVC

Wavelength

(nm)

320-400

290-320

200-290

315-400

280-315

100-280

Other Names

Long

Medium

Short

Blacklight

Erythemal

Germicidal

Near

Near

FarSlide5

CATEGORIES OF UVR

Near UVR- nearer the visible light spectrum but are longer in wavelength

*Longer wavelength

are more beneficial (BIOTIC)

Shorter wavelength are ABIOTICSlide6

PRODUCTIONS OF UVR

I. NATURAL WAY: SUN

II. ARTIFICIAL WAYSlide7

I. NATURAL WAY: SUN

5-10% of the sun’s energy is in the UVR range (180-400 nm)

UVA 6.3% of sunlight during summer; UVB 0.5%

Both UVA & UVB can be involved in sunburn and skin diseasesSlide8

II. ARTIFICIAL WAY

Passage of electric current thru gas (vaporized mercury)

Collision with the electrons flowing between the lamp’s electrodes

Mercury atoms become excited

Excited electrons return to particular electronic states in the mercury atom

Release some of the energy they have absorbed

RADIATIONSlide9

II. ARTIFICIAL WAY

UVR can be produced if the temperature is high enough and pressure is low

UVR= T° + P°Slide10

ARTIFICIAL UVR APPARATUS

John Low

Wadsworth

1. Kromayer lamp

1. Water-cooled lamp (Kromayer lamp)

2. Fluorescent lamp

2. Fluorescent lamp

3. Medium pressure mercury arc lamp (Alpine Sunlamp)

3. Air-cooled lamp (Alpine Sunlamp)

4. Low pressure mercury vapor discharge tubesSlide11

KROMAYER LAMP

a.k.a.

water-cooled lamps

requires pre-heating of 5 minutes

a medium pressure mercury vapor designed to be used in contact with the tissue (i.e. treatment of localized pressure areas and ulcers).Slide12

A. KROMAYER LAMP

wavelengths of the rays produced are concentrated at 366 nm but a wide range of both

UVA & UVB are produced.Slide13
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B. FLUORESCENT LAMPS

low-pressure mercury discharge tubes with a phosphor coating on the inside

absorbs short UVR which causes excitation of the phosphor atoms and remission at a longer wavelengthSlide15
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B. FLUORESCENT LAMPS

gives considerable UVA & UVB output;

NO UVCmore commonly used for Psoriasis affecting large body areasSlide17

C. ALPINE SUN LAMP

a.k.a

air-cooled lampsgenerally used for treatment of generalized skin conditions like Acne

and PsoriasisUsually applied at a distance of 45-50 cmSlide18
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D. LOW PRESSURE MERCURY VAPOR DISCHARGE TUBES

Components:

a. Tube or envelope made of quartz or special glass to allow UVR to pass through

b. Metal electrodes sealed in the ends of the tube

c. Electric circuit to regulate electric currentSlide20

PHYSIOLOGIC EFFECTS

1. Erythema or redding & tanning

- only encountered when

UVB (at 250-297 nm) treatment is used.

Minimal Erythemal Dose = smallest UVR dose to result in erythema that is just detectable by eye between 8-24 hrs after exposureSlide21

PHYSIOLOGIC EFFECTS

2. Pigmentation

- results from formation of melanin in deep regions of the skin & migration of melanin noticeable about 2 days after exposure

-

UVB at 300 nmSlide22

PHYSIOLOGIC EFFECTS

3. Hyperplasia

- occurs at 72 hrs using

UVB

4. Increase skin growth- increase keratinocyte cell turnover so that skin grows more rapidly for a time leading to shedding of most superficial cells at an earlier stageSlide23

PHYSIOLOGIC EFFECTS

5. Vitamin D production

-

UVB convert sterols in the skin (7-dehydrocholesterol) to vitamin D at 280-300 nm

6. Destruction of bacteria-occurs by suppressing DNA and RNA synthesis at UVB at 250-270 nmSlide24

PHYSIOLOGIC EFFECTS

7. Wound healing

- using UVB at 260-280 nm

8. Increase production of RBC

9. Stimulation of steroid metabolism

- UVR promotes vasomotor responses causing antirachitic effectSlide25

PHYSIOLOGIC EFFECTS

10. Immunosuppressive effects

- UVB destroys Langerhans cells & stimulate proliferation of suppressor T cellsSlide26

PHYSIOLOGIC EFFECTS

11. Conjunctivitis / photokeratitis / cataract

- conjunctivitis occur at UVB with 270 nm

- cataracts at UVA since it can pass thru the eye’s lensSlide27

PHYSIOLOGIC EFFECTS

12. Premature aging of the skin

(dry, wrinkled, decreased function of sebaceous and sweat glands)

13. Skin cancers

14. Psychological effectsSlide28

INDICATIONS OF UVR

1. Skin diseases

a.) Psoriasis treatment

b.) Acne vulgaris treatment

To accelerate skin growth, help control infection, sterilize skin surface temporarily

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INDICATIONS OF UVR

2. Healing of wounds (venus ulcers & pressure sores)

To increase rate of skin growth and to provide antibiotic effectSlide30

INDICATIONS OF UVR

3. Vitiligo

Tanning and thickening of the skin

4. Protection of hypersensitive skin Slide31

INDICATIONS OF UVR

5. Alopecia

6. Treatment of vitamin D deficiency Slide32

INDICATIONS OF UVR

7. Pruritus due to biliary cirrhosis or uremia

8. Jaundice for newborn babiesSlide33

CONTRAINDICATIONS

1.

Acute skin conditions (acute eczema, dermatitis)

2. Skin damage due to ionizing radiations like deep X-ray therapySlide34

CONTRAINDICATIONS

3.

Systemic lupus erythematosus can be triggered or exacerbated

4. Photoallergy / photosensitivity (albinism will not tolerate UVR)Slide35

CONTRAINDICATIONS

5.

Porphyrias (rare metabolic disorder)

6. Pellagra (

dermititis due to severe niacin deficiency)Slide36

CONTRAINDICATIONS

7.

Acute febrile illness (pulmonary tuberculosis, severe cardiac involvement, acute diabetes mellitus)

8. Recent skin graftSlide37

PRECAUTIONS

Patients with:

a.) little pigmentation, often seen in blondes and redheads.

b.) conditions like syphilis, alcoholism, cardiac or renal disease, acute psoriasis, acute eczema, elderly and infants. Slide38

PRECAUTIONS

c.) Ingested certain food like strawberries, eggs or shellfish before treatment.

d.) Taking any of the ff: birth control, pills, tetracycline, diuretics and insulin.

e.) Recent superficial heat treatment before UVR radiation.Slide39

DANGERS OF USING UVR

1. Eyes (conjunctivitis)

2. Overdose (too long exposure; too close to the lamp)

3. Previously protected skin

4. Electric shock5. Burns6. Chill7. Sensitizers

8. Change of lampSlide40

LEVELS OF UVR ERYTHEMA

E1

E2

E3

E4

Latent period

6-12 hrs

6 hrs

3 hrs

Less than 24 hrs

Appearance

Mildly pink

Definite pink-red; blanches on pressure

Very red;

does not

blanches on pressure

Angry red

Approx. duration of erythema

Less than 24 hrs

2 days

3-5 days

A week

Skin edema

None

None

Some

BlistersSlide41

LEVELS OF UVR ERYTHEMA

E1

E2

E3

E4

Skin discomfort

None

Slight soreness; irritation

Hot& painful

Very painful

Desquamation

None

Powdery

In thin sheets

In thick sheets

Relation to dose causing E1

1

2.5

5

10Slide42

SELECTION OF DOSAGE LEVEL

DOSAGE

FREQUENCY

1. E1 or Minimal Erythemal Dose may be given to

total body area

Given daily

2. E2



up to

20% of total body area

Every second day

3. E3



up to

250 square cm

of normal skin

Every third or fourth day

4. E4



up to

25 square cm

of normal skin

Once a week or every forth nightSlide43

CALCULATION OF UVR DOSAGE

Basis: determined by performing skin test to get

MED or E1

Two units of measurements to consider:

a.) length of time (seconds)b.)

distance from the lamp (mm)Slide44

CALCULATION OF UVR DOSAGE

Levels of dosage intensity

a.) E1= determined by the skin test b.) E2= 2.5 x E1 c.) E3= 5 x E1

d.) E4= 10 x E1Slide45

If the E1 of the patient is 50 s at a distance of 200 mm, find E3 at 200 mm.Slide46

CALCULATION OF UVR DOSAGE

Progression of dosage:

a.) E1 is progressed by

25% of the preceding dose

b.) E2 is progressed by 50% of the preceding dose

c.) E3 is progressed by 75%

of the preceding dose Slide47

If E1 is 30 s at 200 mm, find the second progression (P2E1).Slide48

CALCULATION OF UVR DOSAGE

Alteration of intensity with distance

-guided by Law of Inverse Square

which states that as the distance between the source and the patient increases, the intensity decreases in proportion to the square of the distance.

Formula: I = 1/ d2 Slide49

nt

= ot x nd2 od2Slide50

CALCULATION OF UVR DOSAGE

Using Kromayer lamp:

-use the levels of dosage for intensity since the distance is always at 25 mm.

Using air-cooled lamps:

-distance is from the burner of the lamp to the patient and follow the Inverse square law formula.Slide51

Using the

kromayer, if the E1 of the patient is 2 s I/C, find the E1 at 100 mm.Slide52

Using the air cooled lamp, if the E1 at 400 mm is 30 s, find

the E1 at 200 mm.Slide53

CALCULATION OF UVR DOSAGE

Using an applicator:

1.) Compute for coefficient of the applicator: *Length of applicator in mm divided by 25

2.) Compute for applicator dose: *in-contact dose (secs at mm) x coefficient of applicator (in mm)Slide54
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THANK YOU!