A study of the solar effect on actinic keratoses by quantification of elastic fibres using an image analysis system

It is widely accepted that elastotic changes of the skin are primarily an i ndicator of cumalative sun exposure of the dermis: and are a characteristic finding of actinic keratoses, To date, there ha, e been few reports that m easure the amount of elastic tissue objectively and quantitatively,, especi ally in actinic keratoses, The computerized image analysis method has prove d useful recently in determining the area of elastic fibres, Using this met hod, we objectively quantified the elastotic tissue in actinic keratoses an d evaluated the relationship between the degree of dermal elastosis, epider mal at? pia and histological types of actinic keratoses, Of the 28 actinic keratoses studied, the average percentage area of the elastic fibre was 40. 48 +/- 14.48 (mean I SD) percentile. There was a 3.65-fold increase in the amount of elastic fibre in actinic keratoses compared with that of seborrho eic keratoses occurring on the face (p < 0.00001). In addition, the more se vere the atypia, the greater the area of elastic fibres in a representative section of the dermis, In conclusion, we observed that on quantitative ass essment of elastic tissue in actinic keratoses, the percentage area of the elastic fibres in a representative section of the dermis ranges from 34.86 to 46.11%. This result may pro, ide information for use in histological dia gnosis of actinic I;keratoses and evidence for the possible role of sunligh t in the pathogenesis of actinic keratosis.