Abstract
The theory of selective photo-thermolysis (SP) suggests the occurrence of optimal damage when the laser pulse duration (PD) equals the target thermal relaxation time (Tr). This study examines the clinical relevance of this theory. The study design and methods consisted of prospective, randomised, blinded, controlled study of KTP 532-nm laser treatment of 28 telangiectatic facial vessels. The PD varied from 0.13 to 1.71 times Tr (factor of 13). All vessels achieved marked improvement or clearance. The analysis of proportions reaching clearance over marked improvement for small and large calibre vessels shows a better outcome when the PD is nearer to the Tr (86% vs 57%; P=0.09, 95% CI for difference −3% to 60%). Logistic regression analysis shows that, as the ratio of PD to Tr increases (PD near to or higher than Tr), the chance of clearing improves (P=0.169; 95% CI 0.34 to 341). This study has shown that, for the range of vessels investigated: (1) marked improvement or clearance may be achieved using PDs that range between 0.13 and 1.71 times the Tr; and (2) it also reveals an overall trend towards a higher proportion of clearance when the PD is near to or higher than the Tr.
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References
Anderson RR, Parrish JA (1983) Selective photothermolysis: precise microsurgery by selective absorption of pulsed radiation. Science 220:524–527
Altshuler GB, Anderson RR, Manstein D, Zenzie HH, Smirnov MZ (2001) Extended theory of selective photothermolysis. Lasers Surg Med 29(5):416–432
West TB, Alster TS (1998) Comparison of the long-pulse dye (590–595 nm) and KTP (532 nm) lasers in the treatment of facial and leg telangiectasias. Dermatol Surg 24:221–226
Adrian RM, Tanghetti EA (1998) Long pulse 532-nm laser treatment of facial telangiectasia. Dermatol Surg 24:71–74
Gupta G, Bilsland D (2000) A prospective study of the impact of laser treatment on vascular lesions. Br J Dermatol 143:356–359
Clark C, Cameron H, Moseley H, Ferguson J, Ibbotson SH (2004) Treatment of superficial cutaneous vascular lesions: experience with the KTP 532 nm laser. Lasers Med Sci 19:1–5
Suthamjariya K, Farinelli WA, Koh W, Anderson RR (2004) Mechanisms of microvascular response to laser pulses. J Invest Dermatol 122:518–525
Anderson RR, Parrish JA (1981) The optics of human skin. J Invest Dermatol 77:13–19
Gambichler T, Avermaete A, Wilmert M, Altmeyer P, Hoffmann K (2001) Generalized essential telangiectasia successfully treated with high-energy, long-pulse, frequency-doubled Nd:YAG laser. Dermatol Surg 27:355–357
Dierickx CC, Casparian JM, Venugopalan V, Farinelli WA, Anderson RR (1995) Thermal relaxation of port-wine stain vessels probed in vivo: the need for 1–10-millisecond laser pulse treatment. J Invest Dermatol 105:709–714
Fiskerstrand EJ, Svaasand LO, Kopstad G, Ryggen K, Aase S (1996) Photothermally induced vessel–wall necrosis after pulsed dye laser treatment: lack of response in port-wine stains with small sized or deeply located vessels. J Invest Dermatol 107:671–675
Acknowledgement
We thank the Medical Photography Department, Ninewells Hospital and Medical School, Dundee, Scotland, for enabling us to carry out this study.
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Cameron, H., Ibbotson, S.H., Ferguson, J. et al. A randomised, blinded, controlled study of the clinical relevance of matching pulse duration to thermal relaxation time when treating facial telangiectasia. Lasers Med Sci 20, 117–121 (2005). https://doi.org/10.1007/s10103-005-0354-x
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DOI: https://doi.org/10.1007/s10103-005-0354-x