Treatment of cutaneous vascular lesions using multiple-intermittent cryogen spurts and two-wavelength laser pulses: numerical and animal studies.
نویسندگان
چکیده
BACKGROUND AND OBJECTIVES Presently, cutaneous vascular lesions are treated using a single cryogen spurt and single laser pulse (SCS-SLP), which do not necessarily produce complete lesion removal in the majority of patients. In this study, the feasibility of applying multiple cryogen spurts intermittently with multiple two-wavelength laser pulses (MCS-MTWLP) was studied using numerical and animal models. STUDY DESIGN/MATERIALS AND METHODS Two treatment procedures were simulated: (1) SCS+532 nm SLP; and (2) MCS+532/1064 nm MTWLP. Light transport and heat diffusion in human skin were simulated with the Monte Carlo method and finite element model, respectively. Possible epidermal damage and blood vessel photocoagulation were evaluated with an Arrhenius-type kinetic model. Blood vessels in the rodent window chamber model (RWCM) were irradiated with either SLP or MTWLP. Laser-induced structural and functional changes in the vessels were documented by digital photography and laser speckle imaging (LSI). RESULTS The numerical results show that the MCS-MTWLP approach can provide sufficient epidermal protection while simultaneously achieving photocoagulation of larger blood vessels as compared to SCS-SLP. Animal studies show that MTWLP has significant advantages over SLP by inducing irreversible damage to larger blood vessels without adverse effects. CONCLUSIONS MCS-MTWLP may be a promising approach to improve therapeutic outcome for patients with cutaneous vascular lesions featuring large blood vessels.
منابع مشابه
Experimental study of multiple-intermittent cryogen spurts and laser pulses for the treatment of port wine stain birthmarks
Cryogen spray cooling (CSC) is used to minimize the risk of epidermal damage during pulsed laser treatment of port wine stain (PWS) birthmarks. Unfortunately, the current approach to CSC does not provide the necessary epidermal protection for all patients, particularly those with darker skin types. Therefore, alternative approaches need to be sought to improve PWS laser therapy. On a previous n...
متن کاملHeat Transfer Dynamics during Treatment of Port Wine Stain Birthmarks with Multiple-intermittent Cryogen Spurts and Laser Pulses
Port wine stain (PWS) is a congenital, progressive vascular malformation of human skin. Presently, all PWS patients are treated using single cryogen spurt and single laser pulse exposure (SCS-SLP), which does not produce complete lesion blanching in the vast majority of patients. In this study, the feasibility of applying multiple cryogen spurts intermittently with multiple laser pulse exposure...
متن کاملCryogen spray cooling efficiency: improvement of port wine stain laser therapy through multiple-intermittent cryogen spurts and laser pulses.
BACKGROUND AND OBJECTIVES Cryogen spray cooling (CSC) is used to minimize the risk of epidermal damage during laser treatment of port wine stain (PWS) birthmarks. Unfortunately, CSC may not provide the necessary protection for patients with high concentrations of epidermal melanin. The objectives of this study are to: (1) provide a definition of cooling efficiency (eta) based on the amount of h...
متن کاملEffects of cryogen spray cooling and high radiant exposures on selective vascular injury during laser irradiation of human skin.
BACKGROUND Increasing radiant exposure offers a means to increase treatment efficacy during laser-mediated treatment of vascular lesions, such as port-wine stains; however, excessive radiant exposure decreases selective vascular injury due to increased heat generation within the epidermis and collateral damage to perivascular collagen. OBJECTIVE To determine if cryogen spray cooling could be ...
متن کاملIntermittent cryogen spray cooling for optimal heat extraction during dermatologic laser treatment.
Fast heat extraction is critically important to obtain the maximal benefit of cryogen spray cooling (CSC) during laser therapy of shallow skin lesions, such as port wine stain birthmarks. However, a film of liquid cryogen can build up on the skin surface, impairing heat transfer due to the relatively low thermal conductivity and higher temperature of the film as compared to the impinging spray ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Lasers in surgery and medicine
دوره 39 6 شماره
صفحات -
تاریخ انتشار 2007