Comparative numerical analysis and optimization of blood vessels heated using various lasers

Pushkareva, A. E.; Ponomarev, Igor; Topchiy, Sergey B.; Klyuchareva, S. V.

doi:10.1088/1555-6611/aac903

Cited by 7 publications

(11 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The skin was assumed to have a multilayer plane-parallel structure of finite width and infinitely extended along the skin surface. 13 The skin structure was considered to consist of the epidermis including a basal layer (stratum basale) containing melanin, as the skin chromophore, and dermis composed of discrete blood vessels keeping oxyhemoglobin, as the most potent chromophore. Epidermis including the basal layer of 15 μm was assumed to have the thickness of 70 μm.…”

Section: Methodsmentioning

confidence: 99%

Numerical Modeling and Clinical Evaluation of Pulsed Dye Laser and Copper Vapor Laser in Skin Vascular Lesions Treatment

2018

View full text Add to dashboard Cite

Introduction: Different yellow lasers have been successfully used for the treatment of vascular lesions. This study is aimed to ascertain the role and efficiency of copper vapor lasers (CVLs) and pulsed dye lasers (PDLs) for the treatment of vascular lesions using numerical modeling and to compare results with our clinical experience. In this study we aimed to develop criteria for the choice of more efficient laser exposure mode, investigate more relevant modes of laser irradiation to ensure selective photothermolysis of target vessels, and compare the CVL and PDL efficiency in the course of patients with skin vascular lesions (SVL) treatment. Methods: We performed numerical simulation of the processes of heating a vessel with CVL and PDL to temperatures at which its coagulation could occur. Calculated fluencies were compared with clinical results of laser therapy performed on 1242 patients with skin hemangiomas and vascular malformations (SHVM), including 635 patients treated with CVL and 607 patients treated with PDL. PDL and CVL provided excellent results in 40 and ten days after treatment. The treatment was not painful. Patients did not need anesthesia. Postoperative crusts were greater with PDL than with CVL. Results: Results of computer simulation of a selective vessel heating using PDL and CVL radiation are presented. By results obtained, depth of the location and sizes of vessels that could be selectively heated to more than 75°C are determined. Conclusion: Based on calculated and clinical data, the heating mode for dysplastic vessels using a series of CVL micropulses could be regarded to be safer and more efficient than the mode of a PDL short, powerful pulse.

show abstract

Section: Methodsmentioning

confidence: 99%

Numerical Modeling and Clinical Evaluation of Pulsed Dye Laser and Copper Vapor Laser in Skin Vascular Lesions Treatment

2018

View full text Add to dashboard Cite

show abstract

“…For modeling, we used the Matlab mathematical programming system and its application Femlab for solving partial differential equations using the Finite element method. 4,5 The geometry of the model is shown in Figure 1. A three-layer model, including the dermis, in which the vessel was located, the epidermis with a thickness of 70 microns, and the epidermal basal layer, with a thickness of 15 microns, represented the skin.…”

Section: Modelmentioning

confidence: 99%

“…Copper vapor laser (CVL) radiation at a yellow wavelength at 578 nm provides the maximum heating selectivity of dysplastic vessels and clinical effectiveness and safety in the PWS treatment of patients. 4 The choice of laser treatment parameters allows the photodestruction of dysplastic vessels in PWSs with minimal post-radiation changes in dermal collagen. 5 There has been little clinical data using the CVL in PWS treatment in Asian people with Fitzpatrick skin type III-V. 6,7 PWS treatment is more difficult and unpredictable in patients with darker skin phototypes since skin of color absorbs light energy better than fair skin.…”

Section: Introductionmentioning

confidence: 99%

Numerical Modeling of The Dysplastic Vessel Heating in PWS by Yellow 578 nm Copper Vapor Laser Radiation for Different Skin Phototypes

2022

View full text Add to dashboard Cite

Introduction: Many clinical studies and protocols have been written about laser treatment for fair skin phototypes. However, for dark-skinned phototypes, information is limited, and the risk of burns is higher, especially if the same settings are recommended for fair skin. Competitive epidermal melanin absorption decreases the light energy reaching dysplastic vessels in a port-wine stain (PWS), preventing the vessel from achieving the temperature of the desired clinical result. Therefore, the choice of safe laser settings for different skin phototypes can be realized using numerical modeling of PWS vessel heating. This study aimed to demonstrate the algorithm for choosing both effective and safe photodestruction of dilated dermal vessels in PWS with the copper vapor laser (CVL) at 578 nm for different skin phototypes. Methods: We used the multilayered skin model with different melanin content for detecting the safe laser parameters for PWS treatment. The calculation of the selective heating of the vascular component with CVL radiation at yellow 578-nm wavelengths for different skin phototypes was performed via Matlab mathematical programming system and its application Femlab for solving partial differential equations using the Finite element method. Results: We determined the location, depth, and size of blood vessels that could be selectively heated to coagulation temperature for different skin prototypes. CVL fluence values need to be reduced almost two times for skin phototype IV than for skin phototype II to provide safe CVL treatment. The maximum depth of the location of the vessels, which can be selectively heated to coagulation temperature, also decreased for dark skin phototypes. Histological and histochemical findings validated the results of our calculations. Conclusion: To our knowledge, the use of numerical simulation to optimize has not yet been considered. According to our calculations, CVL could selectively heat the dilated vessel, which occurred in purple and proliferative-type PWS for dark skin at the reduced fluence range and depth.

show abstract

“…Для сравнения эффективности нагрева ткани и расположенных в ней сосудов увеличенного диаметра излучением ЛПМ и диодного лазера была выполнена процедура моделирования нагрева кровеносного сосуда с использованием пакета математического моделирования Matlab и его приложения для решения дифференциальных уравнений в частных производных Femlab, методика которой описана в [22].…”

Section: материал и методыunclassified

“…Численное моделирование [22] показало, что сосуды увеличенного диаметра нагреваются излучением ЛПМ сильнее, чем окружающая их ткань. По этой причине злокачественная ткань базалиомы, для которой характерна высокая васкуляризация [17,18], всегда будет нагреваться лазерным излучением ЛПМ в большей степени, чем здоровая ткань.…”

Section: материал и методыunclassified

Treatment of basal cell cancer in the periorbital area using a pulsed copper vapour laser

Klyuchareva

Ponomarev

Topchy

et al. 2018

Vestnik dermatologii i venerologii

View full text Add to dashboard Cite

An increase in life expectancy in developed countries is inevitably accompanied by an increase in the number of nonmelanoma skin diseases, which are primarily represented by basal cell cancer (BCC) occurring in elderly and old-age patients. The pathogenesis of such diseases is associated both with impaired proliferation and differentiation of the keratinocytes of the epidermal basal layer, as well as with the transformation of the vasculature in the papillary dermis in the vicinity of BCC. In recent years, such conditions have been increasingly treated using CO2 , neodymium, diode and pulsed-dye lasers. In many cases, these devices allow malignant BCC cells to be successfully eliminated. However, the use of near-infrared lasers in the periorbital area is limited due to a higher risk of damaging the organs of the visual system. Therefore, a search for new laser surgery methods that can be used for treating malignant skin tumours seems to be a prospective research direction.Methods. 3 male and 9 female patients diagnosed with primary BCC were treated using a copper vapour laser (Yakhroma-Med). The age of the patients varied from 34 to 77 years. Laser treatment was carried out in one session under the following irradiation parameters: the wavelength of 511 and 578 nm, the average power of up to 3 W and a series of 15 ns pulses. The pause between the pulses was 60 μs, with the exposure time ranging from 200 to 600 ms. The light spot diameter on the skin surface was 1 mm. The follow-up monitoring duration was 24 months.Results. In all the BCC patients, one session of copper vapour laser treatment allowed malignant cells in the disease area to be completely eliminated without relapses during 2 years after the therapy. The duration of skin healing in the irradiated area was 2 weeks in patients under the age of 40 years, compared to 3–4 weeks in elderly patients. After the treatment, short-term side effects, such as a slight edema, erythema and peeling, were observed.

show abstract

Comparative numerical analysis and optimization of blood vessels heated using various lasers

Cited by 7 publications

References 21 publications

Numerical Modeling and Clinical Evaluation of Pulsed Dye Laser and Copper Vapor Laser in Skin Vascular Lesions Treatment

Numerical Modeling and Clinical Evaluation of Pulsed Dye Laser and Copper Vapor Laser in Skin Vascular Lesions Treatment

Numerical Modeling of The Dysplastic Vessel Heating in PWS by Yellow 578 nm Copper Vapor Laser Radiation for Different Skin Phototypes

Treatment of basal cell cancer in the periorbital area using a pulsed copper vapour laser

Contact Info

Product

Resources

About