The MedDerm Phototherapy
Center is one of the highest quality in Southern
California.
Various light therapies are available at MedDerm to treat
a wide variety of medical disorders of the skin.
Phototherapy is the controlled delivery of
artificial ultraviolet light. Ultraviolet light (a portion of
the light emitted by the sun) is subdivided into UVA, UVB and
UVC.
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UVA and UVB light wavelengths are
beneficial for the treatment of a variety of skin disorders
including, but not limited to, psoriasis, vitiligo,
mycosis fungoides (cutaneous T-cell lymphoma), chronic
itching (pruritus and/or prurigo) and various types of
dermatitis (eczema). |
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When UV light is absorbed into the
skin, it suppresses the immune function of the skin. This
helps to rid the skin of immunologic problems that lead
to skin damage and destruction. Fortunately, UV therapy
does not suppress the overall immune function of the body
(systemic immunity). |
Narrowband UVB (NB-UVB) therapy is 311nm
wavelength light that suppresses abnormal lymphocyte function
in the skin. NB-UVB is thought to be superior to Broad Band
UVB light exposure because narrowband light eliminates the
most dangerous shortwave UVB rays. Those short rays are most
highly associated with the induction of skin cancer.
Ultraviolet A-1 spectrum (UVA-1) is 340-440nm
wavelength light (peak output is 370-390nm). UVA-1 is long-wave
radiation that suppresses the function of the peripheral (skin)
T and B lymphocytes. These are important immune cells, however,
in many skin diseases they lead to dysfunctional immune reactions.
Like the shortened UVB exposure of NB-UVB, UVA-1 also provides
an effective therapeutic spectrum without the dangers of short
wave exposure.
The following skin disorders can be treated with
ultraviolet phototherapy. Approximate treatment times
and number of sessions required are listed. Treatments are
usually given 2 to 3 times per week. These vary depending
on the degree of skin involvement and with the skin disease.
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Psoriasis
– approximately 30 sessions to clear and maintenance
sessions after clearance. |
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Vitiligo –
60 sessions or more over 6 to 9 months. |
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Atopic dermatitis
– approximately 15 sessions |
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Morphea/Localized Scleroderma
– approximately 30 sessions |
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Systemic Sclerosis/Scleroderma
– session number varies with skin involvement |
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Granuloma Annulare
– 15 sessions |
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Generalized Pruritus
(itching) – minimum 20 sessions |
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Polymorphous Light Eruption
– begin treatments 3 weeks before planned sun exposure |
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Urticaria Pigmentosa –
25 sessions in most cases |
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Graft vs. Host Disease (GVHD)
- session number varies with skin involvement |
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Cutaneous T-cell Lymphoma
(Mycosis Fungoides) –approximately 30 sessions,
but varies with severity of disease. |
Psoralen and Ultraviolet A Phototherapy (PUVA)
combines the administration of psoralen (OxsoralenTM)
with UVA light exposure 2 to 3 days per week. Oxsoralen
(which can be applied topically or taken orally) makes the
skin more sensitive to UVA. Compared with Broad Band UVB
treatment, PUVA clears psoriasis more consistently and in
fewer treatments. However, it is associated with nausea,
headache, fatigue, burning, and itching. Sunlight must be
avoided after ingesting or applying Oxsoralen to avoid sunburn,
and eye protection must be worn for 24 hours after taking
Oxsoralen by mouth. Long-term PUVA treatment has been associated
an elevated risk of non-melanoma skin cancers and melanoma
in psoriasis patients.
Photodynamic Therapy (PDT) is effective
for the treatment of actinic keratoses (precancers
of the skin) and thin non-melanoma skin cancers (superficial
basal cell carcinoma and superficial squamous cell carcinoma).
PDT can also be used to improve acne vulgaris, sebaceous
gland enlargement and large pore size. PDT is a two-step
procedure that is done on an outpatient basis.
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First, a photosensitizing
medication called aminolevulinic acid (ALA
or Levulan) is applied to the affected skin.
It is selectively absorbed by precancerous and cancerous
skin cells, as well as sebaceous glands. It is allowed
to
“incubate” on the skin for 45 to 120 minutes
prior to exposure to therapeutic light (Blu-U).
The skin cells that have absorbed the ALA photosensitizer
are then “activated”
to selectively destroy
the cells that absorb ALA and undergo the photochemical
reaction. In some patients, both blue light (Blu-U) and
red light (BBL) are used to quench the photochemical
reaction and remove background photodamage.
PDT is relatively pain free. The major side effect
is temporary inflammation of the skin that appears
as red, tight skin initially and then red, peeling
skin which can take up to 3 days to heal. It may take
7-10 days to heal if the treated individual is exposed
to sun during the 48 hours following treatment. After
PDT is performed, it is important to avoid exposure
to bright light and/or direct sunlight to prevent excessive
redness and swelling. Normal indoor lighting, television
and computer exposure are fine. In some cases, two
treatments may be needed to clear all precancerous
lesions; most clear in one treatment. The results are
often maintained for many years if careful sun protection
is followed thereafter. |
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