introduction light therapy - fh münster€¢ introduction • light therapy ... neurodermatitis ......
TRANSCRIPT
Medical Light Sources
• Introduction• Light therapy
– Full spectrum– UV– IR
• Applications– Endoscopy– Medical LASER
Light Therapy in History• Tuberculosis since
1895• Rachitis since 1921
Sanatoriums in Davos, Braunwald….7h in sunlight
Generation of Vitamin D3– Produced in the skin– Needs UV-B (290 - 315
nm)
Vitamin D3
Utilisation of Vitamin A660-668Red
Heat Therapy880-904IR
Vitalization446Blue
Tanning skin315-400UV-A
Synthesis of Vitamin D3280-315UV-B
Disinfection200-280UV-C
Important forWavelength[nm]
SpectralRange
Lack of Light Causes• Depressions• Sleep disorder
Therapy:½ h with 10.000 Lux oror 2 h with 2500 Lux
Decomposition of Melatonin
Decomposition of MelatoninSu
ppre
ssio
n of
Mel
anto
nin
[%]
Radiant flux density [µW*h/cm2] Time of day
Time of irradiation (3h)
Con
cent
ratio
nof
Mel
anto
nin
Icterus neonatorumor Crigler-Najjar Syndrome
Decomposition of erythrocytes in the first days after birthForming of Bilirubin causes the icterus
Exposure with blue light (460 nm) leads to Lumirubin
Philips Special Blue lampsF20T12/BB or F40/BB
Philips Special Blue lamps F20T12/BBor F40/BB
BaMgAl10O17:Eu2+
Wavelength [nm]
Em
issi
on In
tens
ity[a
.u.]
Therapy for Skin Diseases
Acne• Light with wavelength of 415 nm• Oxygen radicals are generated on
the skin surface
Bacteria are destroyed
Problem: proliferation hyperkeratosis– scarring– increased cell devision
α-Ba3Y(BO3)3:Eu
Therapy for Skin diseases
Neurodermatitis• UV-B (311 nm, LaB3O6:Bi3+,Gd3+)• In severe cases additionally UV-A (340 - 400 nm
LaPO4:Ce3+)
Wavelength [nm]
Em
issi
on in
tens
ity[a
.u.]
Tanning of skinUV-A (315-400nm) • 95% of radiation• Tanning of the epidermis
immediate reactionshort term effect
UV-B (280-315nm)• 5% of radiation• Tanning of the deeper skin
takes 2-3 dayslong term effect
Oxidation of Melanin causesthe tanning.
Wavelength [nm]
Em
issi
on in
tens
ity[a
.u.]
DisinfectionUV-C (200 - 280 nm)• Absorbtion of the DNA at 254 nm
degeneration of thegenetic information
reproduction is inhibited
• 99.99% of microorganism are killed• Works in spits of a second
Absorption curve of the DNA
Wavelength [nm]
Inte
nsity
[a.u
.]
254nmSpectral efficiency curveof cell inacitvation
Infrared Therapy• rheumatism
• neurodermatitis
• backache
• cancer therapy (high energy IR-A)
IR-A and IR-B
• Incandescent bulb with a filter
• YAG:Nd Laser
IR-C
• heated-up ceramic
Endoscopy• Light source:
• Xenon-Lamp• LED
• Fibre-optic• Glasfibre• Polymeric optical fiber
high refractiveindex
Medical LASER• Erasing of tattoos YAG:Nd (1064 nm) and Ruby (694 nm)• Correction of eyes ArF (193 nm) and Ti:Saphir (800 nm)• Hair removal Alexandrit Laser (755 nm)• Laser scalpel CO2-Laser (10.6 µm), YAG:Nd (1064 nm)
References• Light and Lasers (Jerry Joseph Wilmink, Vanderbilt University, Nashville)• Leben mit optischer Strahlung (Joachim Fisch, Karin Bieske)• Informationen zur Tiefenwärme (www.pooldoktor.at)• Licht in der Geschichte der Medizin (Dr. med. Urs Stillhard)• Alternative Medizin – Die Heilkraft des Lichts
(www.mweisser.50g.com/licht.htm)• Laser in der Medizin (Seminar Vortrag von Steffen Eich)• www.wikipedia.org• Lichttechnik und Leuchtstoffe (Vorlesungsskript Prof. Dr. Thomas Jüstel)