PMID- 21384398
OWN - NLM
STAT- MEDLINE
DCOM- 20110711
LR  - 20161125
IS  - 1096-9101 (Electronic)
IS  - 0196-8092 (Linking)
VI  - 43
IP  - 2
DP  - 2011 Feb
TI  - Intense pulse light and 5-ALA PDT: phototoxic effects in vitro depend on the 
      spectral overlap with protoporphyrine IX but do not match cut-off filter 
      notations.
PG  - 176-82
LID - 10.1002/lsm.20970 [doi]
AB  - BACKGROUND AND OBJECTIVES: Successful photodynamic therapy (PDT) requires a light 
      source by which light is absorbed by the photosensitizer. Such absorption is 
      achieved by adapting the emission spectrum of the lamp to the absorption-spectrum 
      of the photosensitizer. Intense pulsed light sources (IPLs) are widely used in 
      dermatology, but a standardized protocol for IPL-PDT is not available. Five 
      different IPLs were chosen to evaluate their efficacy for PDT in vitro and the 
      possibility for developing a standard protocol for PDT. MATERIALS AND METHODS: 
      Emission-spectra of IPLs were measured with an optical spectrograph and compared 
      with the absorption spectrum of protoporphyrine IX (PpIX). Keratinocytes were 
      incubated with 5-ALA and illuminated with the IPLs. Cell viability was determined 
      for radiant exposures ranging from 0 to 504 J/cm(2) and pulse durations from 8 to 
      100 milliseconds. A standard LED light source was used as a reference. RESULTS: 
      Cell viability is less effectively reduced by 5-ALA-PDT with IPLs than by a LED 
      light source. Radiant exposures of the five IPLs ranged between 80 and 
      311 J/cm(2) to achieve the EC(50) value. This value correlated with the spectral 
      overlap of the respective IPL and the absorption-spectrum of PpIX but not with 
      the cut-off filter notations supplied by the manufacturer. CONCLUSIONS: All IPLs 
      assessed emit different spectra because of different filter technologies. 
      Different radiant exposures (J/cm(2) ) were necessary to achieve a photodynamic 
      effect with 5-ALA in vitro depending on these spectra similar to the photodynamic 
      effect of the standard LED light source. IPLs may be applicable in clinical PDT 
      but radiant exposure protocols must be separately evaluated for each single IPL 
      despite similar cut-off filter specifications. Such protocols are highly 
      important for clinical practice to avoid a potential mismatch of excitation 
      wavelengths and to prevent photothermal side effects when light intensities of up 
      to hundreds of W/cm(2) are applied.
CI  - Copyright (c) 2011 Wiley-Liss, Inc.
FAU - Maisch, Tim
AU  - Maisch T
AD  - Department of Dermatology, Regensburg University Hospital, 93053 Regensburg, 
      Germany. tim.maisch@klinik.uni-regensburg.de
FAU - Moor, Anne C E
AU  - Moor AC
FAU - Regensburger, Johannes
AU  - Regensburger J
FAU - Ortland, Christoph
AU  - Ortland C
FAU - Szeimies, Rolf-Markus
AU  - Szeimies RM
FAU - Baumler, Wolfgang
AU  - Baumler W
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Lasers Surg Med
JT  - Lasers in surgery and medicine
JID - 8007168
RN  - 0 (Photosensitizing Agents)
RN  - 0 (Protoporphyrins)
RN  - 88755TAZ87 (Aminolevulinic Acid)
RN  - C2K325S808 (protoporphyrin IX)
SB  - IM
MH  - Aminolevulinic Acid/*adverse effects
MH  - Cell Survival/drug effects
MH  - Clinical Protocols/standards
MH  - Dose-Response Relationship, Radiation
MH  - Humans
MH  - In Vitro Techniques
MH  - Keratinocytes/*drug effects
MH  - Light/*adverse effects
MH  - Photochemotherapy/*methods
MH  - Photosensitizing Agents/*adverse effects
MH  - *Protoporphyrins
MH  - Spectrum Analysis
EDAT- 2011/03/09 06:00
MHDA- 2011/07/12 06:00
CRDT- 2011/03/09 06:00
PHST- 2011/03/09 06:00 [entrez]
PHST- 2011/03/09 06:00 [pubmed]
PHST- 2011/07/12 06:00 [medline]
AID - 10.1002/lsm.20970 [doi]
PST - ppublish
SO  - Lasers Surg Med. 2011 Feb;43(2):176-82. doi: 10.1002/lsm.20970.