PT  - JOURNAL ARTICLE
AU  - C Eker
AU  - S Montán
AU  - E Jaramillo
AU  - K Koizumi
AU  - C Rubio
AU  - S Andersson-Engels
AU  - K Svanberg
AU  - S Svanberg
AU  - P Slezak
TI  - Clinical spectral characterisation of colonic mucosal lesions using autofluorescence and δ aminolevulinic acid sensitisation
AID  - 10.1136/gut.44.4.511
DP  - 1999 Apr 01
TA  - Gut
PG  - 511--518
VI  - 44
IP  - 4
4099  - http://gut.bmj.com/content/44/4/511.short
4100  - http://gut.bmj.com/content/44/4/511.full
SO  - Gut1999 Apr 01; 44
AB  - BACKGROUND AND AIMS Laser induced fluorescence (LIF) from colonic mucosa was measured in vivo with and without δ aminolevulinic acid (ALA) in an attempt to differentiate between neoplasia and non-neoplasia in real time during colonoscopy.METHODS Spectra from 32 adenomas, 68 normal sites, and 14 hyperplastic polyps in 41 patients were obtained with a point monitoring system. Twenty one of the patients had been given a low dose of ALA as a photosensitiser before the examination. Light of 337, 405, or 436 nm wavelength was used as excitation. Stepwise multivariate linear regression analysis was performed.RESULTS With 337 nm excitation, 100% sensitivity and 96% specificity was obtained between normal mucosa and adenomas. Seventy seven per cent of the hyperplastic polyps were classified as non-neoplastic. When exciting with 405 and 436 nm, the possibility of distinguishing different types of tissue was considerably better in the ALA patients than in the non-ALA patients.CONCLUSIONS The in vivo point measurements imply that a good discrimination between normal tissue and adenomatous polyps can be obtained using the LIF technique. Excitation at 337 nm and at 405 nm or 436 nm using ALA gives good results. LIF also shows potential for distinguishing adenomatous from hyperplastic polyps. The number of detection wavelengths could be reduced if chosen properly.ALAδ aminolevulinic acidLIFlaser induced fluorescenceMVLRmultivariate linear regressionPpIXprotoporphyrin IX