Acceleration of ALA-induced PpIX fluorescence development in the oral mucosa

Lasers Surg Med. 2003;32(3):185-8. doi: 10.1002/lsm.10144.

Abstract

Background and objectives: The development of 5-aminolevulinic acid (ALA)-induced tissue fluorescence is optimal 2-4 hours after ALA application. Goal of this work was to develop a means of accelerating oral topical ALA-induced tissue fluorescence.

Study design/materials and methods: In 300 hamsters, DMBA (9,10 dimethyl-1,2-benzanthracene) cheek pouch carcinogenesis produced dysplasia in 3-5 weeks. Topical application of 20% ALA in Eucerin was followed by localized ultrasound treatment (1, 3.3 MHz) in 150 animals. In 75 animals, ALA was applied in an Oral Pluronic Lecithin Organogel (OPLO-an absorption enhancer) vehicle. Seventy-five animals received only topical ALA in Eucerin. Hamsters were sacrificed and cryosections underwent fluorescence measurements, histological evaluation, 20-180 minutes after ALA application. One-way ANOVA detected independent effects of pathology on laser-induced fluorescence (LIF). Two-way ANOVA tested for independent effect of pathology and of OPLO, ultrasound, and interaction effects.

Results: Ultrasound significantly (P < 0.05) accelerated tissue fluorescence development.

Conclusions: Low-frequency ultrasound can accelerate ALA-induced fluorescence development.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Administration, Topical
  • Aminolevulinic Acid / pharmacology*
  • Analysis of Variance
  • Animals
  • Carcinoma, Squamous Cell / pathology
  • Cricetinae
  • Disease Models, Animal
  • Mouth Mucosa / drug effects
  • Mouth Mucosa / pathology*
  • Mouth Neoplasms / parasitology
  • Photosensitizing Agents / pharmacology*
  • Probability
  • Protoporphyrins / pharmacokinetics*
  • Sensitivity and Specificity
  • Spectrometry, Fluorescence / methods*

Substances

  • Photosensitizing Agents
  • Protoporphyrins
  • Aminolevulinic Acid
  • protoporphyrin IX