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INTRODUCTION, PRODUCTION, THERAPEUTIC
INDICATION, CONTRAINDICATION, PRECAUTION
& DANGERS.
Ultraviolet radiation (UVR) covers a small part
of electromagnetic spectrum lying between
the violet end of the VISIBLE LIGHT and X-RAY
REGION.
UVR are INVISIBLE to the human
eyes.
Natural source of UVR is SUN.
UVR provoke CHEMICAL CHANGES &
not simply heat at sites where they
are absorbed.
1. Reflection
2. Refraction
3. Absorption
4. Penetration
Snow Desert area
90%
5%15-30%
The longer the wavelength, the deeper the penetration
UVA (LONG UV) UVB (MEDIUM UV,
ERYTHEMAL UV)
UVC (SHORT UV,
GERMICIDAL UV)
WAVELENGTH 400 – 320nm 320 – 290nm 290 – 200nm
PENETRATION deeper dermis Deep Epidermis
only a small
proportion
reaches the upper
dermis.
absorbed or
reflected
predominantly in
the stratum
corneum and in
upper layers of
the epidermis.
EFFECTS development of
slow natural tan
Produces new
pigment
formation,
sunburn, Vitamin
D synthesis.
Responsible for
inducing SKIN
CANCER
Does not reach
the surface of the
earth so usually
does not affect
the human
UV Radiation
Hour
Monthof theyear
Geographicposition
SunPosition
Elevates mood and improves energy
1. High pressure mercury vapor
lamp – Air cooled.
2. High pressure mercury vapor
lamp – Water cooled ( Kromayer
lamp).
3. Fluorescent lamps
It used for GENERAL UV
IRRADIATION.
The spectrum contains a
large proportion of short UVR
which are undesirable for the
general treatment.
FLUORESCENT TUBES:
The modern treatment methods often require
the use of Long UV without short UV.
So to meet this criteria the fluorescent tubes
are used.
These are similar to the tubes used for
lighting.
It is made of a type of glass which allows long
UV to pass.
The output proportion of this is mainly of Long
UV, Few IRR & some Short UV.
It is mainly used for General Irradiation for
individual or in Group.
The UVR physiological effects
may be divided into 2 groups;
Local – Effects which produced
locally in the area.
General – Results from a systemic
effects of radiation.
In the presence of UVB, 5 to 20 minutes of daily
exposure.
UVB irradiation quickly converts
epidermal 7-dehydrocholesterol
into previtamin D3; the latter
then isomerizes to vitamin D3
(cholecalciferol), which is then
converted in the liver to 25-
hydroxyvitamin D3 and
subsequently in the kidneys
to 1,25-dihydroxyvitamin D3, its
active form. UVR-induced vitamin
D3 synthesis is maximal at
suberythemogenic doses.
APPETITIE & SLEEP BEING IMPROVED
NERVOUSNESS & IRRITABILITY
DECREASED
Acute and Subacute Effects1. Acute inflammatory erythema (sunburn)
2. Pigment darkening and delayed tanning
3. Epidermal hyperplasia
4. Desquamation
5. Immunologic changes
Chronic Effects
1. Photo-aging
2. Photocarcinogenesis
First observable effect of UV Irradiation.
UVR exposure leads to the acute inflammatory
reaction of sunburn.
Wavelengths around 300 nm are the most
erythemogenic, with those between 260 and
280 nm a little less so.
It cause chemical action which result in
IRRITATION & DESTRUCTION of cells. This
causes liberation of “H”-substance which
produce the TRIPLE RESPONSE.
The triphasic response to the firm stroking of the skin
characterized by sharply demarcated erythema, a
brief blanching of the skin, and release of histamine
from the mast cells, followed by arteriolar dilation
causing an intense red flare that extends beyond the
margins of the affected site, and ending with the
appearance of a wheal having the configuration of the
original stroking.
1.
In a few individuals, brief immediate erythema occurs within seconds of UVR exposure and lasts for minutes.
Otherwise, the typical delayed bright red appearance of a sunburn develops confluently on all sufficiently exposed skin, beginning within 30 minutes to 8 hours, peaking at 12 to 24 hours and diminishing over hours to days in the case of UVB exposure.
In the case of UVA, the reaction is deeper red in color, is usually more persistent, and often begins during irradiation, before fading over hours to days.
After excessive exposure, edema and blistering may occur, which, if widespread, may lead to associated systemic symptoms such as chills and malaise. Such reactions are generally followed by pruritus and desquamation over a period of days to weeks.
Photoprotection is the best prevention.
Once excessive UVR exposure has occurred, only symptomatic treatment can be offered (e.g. increased fluid intake, emollient creams or lotions); topical or oral nonsteroidal or steroidal anti-inflammatory agents must be administered as soon as possible after irradiation, or they will not help.
If the sunburn is severe or life-threatening, hospitalization and treatment as for thermal burns are necessary.
1
It is thought that the UVR stimulates
MELANOCYTE & ACCELERATES the
production of MELANIN PIGMENT.
Pigmentation commonly follows an
erythemal reaction.
It varies with the dosage of UVR & the
different individuals.
Following a single exposure to UVR:
Immediate pigmentary darkening
- occurs within minutes and fades over 6–8 hours.
- most obvious in darkly pigmented skin as greyish coloration
- representoxidation & redistribution of pre-existing melanin
or melanin precursors
• Delayed tanning
- develops in genetically competent individuals over hours to
days and persists for weeks to months
• - tyrosinase activity → new pigment production
- the size and number of melanocytes,
- transfer of melanosomes to keratinocytes,
Repeated exposures to UVR:
number of stage IV melanosomes transferred to keratinocytes
number of active melanocytes.
UVR provokes an increased reproduction of
KERATINOCYTES.
This leads to thickening of epidermis which
acts does acts a PROTECTION AGAINST THE
RAYS.
So longer doses are required to repeat an
ERYTHEMAL reaction.
Hyperplasia lasting a month or so occurs over a
period of hours to days following UVB, but
generally not UVA, exposure.
This results from a markedly increased
cellular mitotic rate and DNA, RNA and
protein synthesis.
Hyperplasia of the viable epidermis and
thickening of the stratum corneum result
in several-fold protection against later
sunburning; this adds to, and may
exceed, that simultaneously provided by
delayed tanning, particularly in fair-
skinned individuals.
It is the shedding of dead cells from
the surface of the skin.
The desquamation is proportional to
the intensity of the erythema.
Cutaneous UVB, UVC, and, to some extent,
UVA irradiation
Exerting both pro- and anti-
inflammatory responses
I. Alters epidermal Langerhans cell
function.
II. Generates regulatory T lymphocytes.
III. changes the cutaneous cytokine profile.
refers to cutaneous changes secondary to
long-term exposure to sunlight.
Photoaging is much less pronounced and has
a delayed onset in individuals with more
darkly pigmented skin
1. Solar elastosis
2. Nodular elastosis
3. Weathering nodules
4. Cutis rhomboidalis nuchae
5. Colloid milium
6. Wrinkling (coarse > fine)
7. Favre-Racouchot syndrome
8. Actinic comedonal plaque
9. Poikiloderma of Civatte
10.Solar purpura and hemosiderin
deposition
11.Fragility /photo-onycholysis
12.Pseudoscars
13.Erosive pustular dermatosis
14.Grover’s disease
15.Dyschromia/melasma
16.Solar lentigines,
17.Ephelides (freckles)
18.Actinic keratoses
19.Squamous cell carcinoma
20.Basal cell carcinoma
21.Cutaneous melanoma, especially
lentigo maligna
22.Acquired elastotic hemangioma
Cutis rhomboidalis nuchae
Favre-Racouchot syndrome
Favre-Racouchot syndrome
Colloid milium
Poikiloderma of Civatte
Grover’s disease
1. DERMATOLOGICAL CONDITIONS – Psoriasis,
Acne, Sub acute & Chronic Eczema.
2. Calcium / Phosphorus disease –
Osteomalacia
3. Non pulmonary tuberculosis
4. Local Ulceration – Ulcers, Pressure sores,
Surgical incision
5. Counter Irritant Effect.
The principle therapeutic uses of UVR are of SKIN
DISEASES
1. PSORIASIS:-
In this state the aim of UVR irradiation is to decrease the
DNA synthesis in the cells of the skin & to improve the skin
condition
Acne is also a skin condition which presents PUSTULES,
PAPULES formed by blocking of sebaceous pores & hair
follicles affecting mainly the face, chest & back.
The more severe & long lasting forms cause disfiguring &
serious distress.
Using UVR is aiming to produce desquamation to open the
blocked pores and hair follicles.
E2 dose is given to the face, chest and neck.
It is an INFLAMMATORY RESPONSE in
the skin associated with OEDEMA.
The patient suffers marked ITCHING
with REDNESS, SCALING, VESCILES &
exudation of serum on the skin.
A mild UVR treatment will help. (Sub
acute & Chronic stage)
It is a condition in which destruction of
MELANOCYTES in local areas causes WHITE
PATCHES to appear on the skin.
Both UVA & UVB stimulate melanocyte activity.
UVA seems to provoke a DARKER & LONGER
LASTING TANNING.
UVB provokes more THICKENNING.
Infected wounds such as
1. ULCERS
2. PRESSURE SORES
3. SURGICAL INCISIONS are often treated with HIGH
DOSES of UVR.
The aim of UVR irradiation is to destroy the surface
bacteria, remove the (SLOUGH) infected material
& promote repair.
E3 dose is sufficient, the dose is may be given daily
and is not being applied to normal skin.
The aim of UVR mainly UVA is to
stimulate the GROWTH of
GRANULATION TISSUE & SPEED
UP REPAIR.
Example for non infected wounds
are – Venous / Arterial ulcers.
It is used to produce a strong
counter irritation effect over
the site of DEEP SEATED PAIN.
E4 dose is given to cause
discomfort and producing mask
of pain.
1. Pulmonary Tuberculosis
2. Severe cardiac disturbances
3. Systemic Lupus Erythematosis
4. Severe Diabetes
5. Known Photosensitivity.
7. Photosensitizing medication.
8. Deep x – Ray therapy.
9. Acute Febrile illness
10. Recent skin grafts.
Porphyria
Sarcoidosis
Xeroderma pigmentosum
Acute psoriasis
Generalized dermatitis
Acute eczema
Herpes simplex
Hypersensitivity to
sunlight
1. Shock
2. Eyes - UVR may produce conjunctivitis,
iritis or cataract.
3. Over Dosage – UVR burn can occur.
Mainly E4 reaction
4. Ozone – Important to ensure adequate
Ventilation in the area.
Proper patient education should be given:-
1. Wear Goggles
2. Observe & monitor the skin condition
3. Keep skin moisture following exposure to UVR
4. Pigmentation changes are to be expected &
are a normal response.
5. Prolonged & repeated exposure leads to
premature aging.
It is used to assess the individual patients (ERYTHEMAL) reaction to UVR irradiation.
The basis for any calculation of any UVR dosage is the MED (MINIMAL ERYTHEMA DOSE)
This MED refers to the response of erythema for the dose to be given
The patient must understand that the purpose of the MED test is to DETERMINE just how much EXPOSURE TIME is necessary based on their skin sensitivity.
It is a slight reddening
(erythema) of the skin
which takes from 6 – 8hrs
to develop & which is still
just visible at 24hrs.
1. The area chosen for the test is of importance.
2. Because the patient is to inspect at regular
intervals a convenient, visible site is essential.
3. It should be clear of skin disease.
4. The FLEXOR SURFACE of the FOREARM is the most
usual site.(Other sites are – Abdomen, Medial aspect
of arm / thigh)
5. The selected site should be cleaned with soap &
water to remove surface grease.
6. Cover the patient other areas leaving only the
forearm exposed to UVR.
7. Three to Five holes of at least 2cm² & 1cm
apart are cut in a piece of
lint/paper/cardboard is taken for irradiation of
UVR along with a slide cover – to pull up to
reveal one opening at a time.
8. This cutting is fixed to the forearm with adhesive
plaster.
9. The cuttings are of different sizes & shapes in-
order to make IDENTIFICATION OF THE ERYTHEMA
EASIER for the patient.
10. Allow the lamp to warm up according to the
manufacturer instructions.
11. Place the lamp PERPENDICULAR to the area being
tested (Forearm) & a DISTANCE of 60 to 90cms from
the site.
12. Expose the 1st opening for 30sec, then expose the
2nd opening for another 30sec & go on till the last
opening
13. So the 1st opening would receive the longest
exposure time & the last opening would receive the
least amount of exposure time.
14. Switch off the lamp
15. Instruct the patient to MONITOR the forearm
every 2hrs & note which opening or shape appeared
pink / red first & when it faded / disappeared.
16. The patient is also given a card similar to the
opening to make a note.
Degree
of
Erythe
ma
Laten
t
perio
d
In HRS
Appearance
color
Duration
of
Erythema
Skin
Oedema
Skin
discomfort
Desquam
ation of
skin
Relation
to
E1 Dose
E1
(MED)
6-8 MILDLY PINK <24hrs NONE NONE NONE E1
E2 4-6 Definite PINK
RED. Blanches
on Pressure
2 Days None Slight
Soreness,
Irritation
POWDE
RY
2.5% of
E1
E3 2-4 Very red,
Does not
blanch on
pressure
3-5 Days Some Hot &
Painful
IN THIN
SHEETS
5% of
E1
E4 <2 Angry Red A Week BLISTER Very
Painful
THICK
SHEETS
10% of
E1
The skin response to UVR depends on;
1. The quantity of UVR energy applied to unit area
of the skin.(Depends on);
a) The output of lamp – Make, Type, Aging
b) Distance between the lamp & the skin – Inverse
square law
c) Angle at which radiations fall on the skin – cosine
law
d) Time for which radiations are applied
2. The sensitivity of the skin
1. An E1/MED – Given to the total body area
(Whole body)
2. An E2 - May not be given to up to 20% of
total body area
3. An E3 – May not be given to up to 250cm² of
normal skin
4. An E4 – May only be given to an area up to
25cm² of normal skin.
Key points
Gilaberte Y, González S. Actas Dermo-Sifiliográficas. 2010; 101: 659-72
Gilaberte Y, González S. Actas Dermo-Sifiliográficas. 2010; 101: 659-72
Sunscreen doesn’t offer 100% protection.
SPF(Sun Protection Factor) 30+ sunscreen blocks 96% of UV; SPF 15+ blocks out 93%.
In addition to sunscreen, wear a hat, sunglasses, more clothing, and seek shade.
Most cotton and cotton/polyesterfabrics protect against 95% of UV, but are less effective if wet, faded, or aged.
Sunscreens are photochemical systems thatabsorb or reflect UV radiation.
Frequently use of sunscreens is the bestphotoprotection strategy.
The first sunscreen was marketed in 1930 Actually there are 28 chemical filters in
Australia, 26 in Europe and 14 in USA.
Kockler J, Oelgemoller M, Robertson S, Glass B. Journal of Photochemistry and Photobiology. 2012; 1-17
Dispersion
UVR
Chemical or physical filters
Reflection
La capacidad de eritema depende◦ Longitud de onda de radiación
◦ Fotosensibilidad del individuo
◦ DEM uso estudios observacionales
SPF = ----------------MED protected
MED unprotected
Kockler J, Oelgemoller M, Robertson S, Glass B. Journal of Photochemistry and Photobiology. 2012; 1-17
20 min before and 2 - 3 hours
SPF 30 (97.5 UVB)◦ 370nm
High UVA protection
SPF 30 UVA highprotection
50- 80% solar damage isbefore 18
Correct solar protection
Walker D. Journal of Pediatric nursing. 2011 Article in press
Beyond the violet UV and Skin Karen Zapata Montenegro Dermatology and Dermatologysurgery CSS
Bolognia 2nd & 3rd ed.