1. The Objective Identification of Dermatoscopic Features using Spectrophotometric Intracutaneous Analysis

2. Marc Moncrieff 1,4, Symon Cotton 2, Ela Claridge 3, Per Hall 1 1 - Department of Plastic & Reconstructive Surgery, Addenbrooke’s Hospital, Cambridge, UK 2 - Astron Clinica, Cambridge, UK 3- Department of Computer Science, University of Birmingham, UK 4 - Department of Plastic & Reconstructive Surgery, West Norwich Hospital, Norwich, UK

3. SIA Technique developed in UK Analyses remitted light from the skin Produces ‘SIAgraphs’

4. Epidermal melanin Collagen Blood Dermal melanin Array spectrometerLight SIA

5. Total Melanin SIAgraph

6. Tumour punches holes in collagen Collagen thrown into whorls and rosettes around invasive nodule Thickening of collagen at invasive margin Collagen SIAgraph

7. Blood displaced by invasive tumour Erythematous blush at invading margin Blood SIAgraph

8. Dermal Melanin SIAgraph

9. Early Trial Results FeatureSens (%) Spec (%) Melanin Globules100 8.4 Dermal Melanin 96.156.8 No Biaxial Symmetry96.229.7 Dermal Melanin Globules88.566.6 Collagen Holes 78.874.0 Asymmetry76.962.2 Erythematous Blush 75.065.5 Blood Displacement 7570.3 Biaxial Symmetry 3.870.3 Displacement with Blush63.584.8

10. Early Trial Results

13. Very simple features identified As accurate as dermatoscopy Results do not include interpretation of dermatoscopic features

14. Skin Surface Microscopy / Dermatoscopy A (useful) adjunct to clinical diagnosis Limitations –training very limited and very necessary –subjective findings –subjective interpretation

15. Blue Formed by: –Dermal melanin –dermal Hb –thinning of collagen –thickening of keratin Hidden by: – epidermal melanin – thrombosis

16. Bahmer et al (1990): “Histopathologically this corresponds to superficial fibrosis with melanophages and / or pigmented malignant cells in the papillary dermis” Bahmer et al (1990) J Am Acad Dermatol 23: pp. 1159-62 Blue - Grey (white) Veil

17. Menzies et al (1996): “It is the single most significant surface microscopic finding of invasive melanoma” Menzies et al (1996) An Atlas of Surface Microscopy of Pigmented Skin Lesions (p.18) Blue - Grey (white) Veil

19. Blue-Grey Veil x

20. =

21. Histology

22. Summary Blue/grey veil detected by SIAscopy Sensitivity = 96% for invasive melanoma Allows objective assessment of surface microscopic features according to underlying histopathology The SIAscope is a diagnostic tool in its own right