The correct answer is A. Pulsed dye laser.
The pulsed dye laser (PDL) is considered to be the laser of choice for the treatment of many cutaneous vascular lesions, especially facial telangiectasias, port-wine stains, superficial hemangiomas, poikiloderma of Civatte, and erythematotelangiectatic rosacea.
2 – KTP laser: KTP laser can be used to effectively treat some vascular lesions (e.g. telangiectasias) in a purpura-free manner. While it can be used to treat vascualr lesions including telangiectasias, pulsed dye laser is the laser of choice for treatment of cutaneous vascular lesions such as telangiectasias. 3 – Intense pulsed light: IPL is most commonly used for patients with phototypes I–III with chronic photodamage or for hair removal. For treatment of patients with more darkly pigmented skin, longer wavelength filters or lower fluences plus longer pulse widths can be used. Filters can also be used for other specific indications, e.g. treatment of vascular lesions. Although it can be used to treat vascular lesions, PDL is considered to be the laser of choice for treatment of facial telangiectasias. 4 – Diode laser: Diode lasers can be used to treat leg venulectasias and telangiectasias (“spider veins”), blue reticualr veins, and venous malformations. However, a pulsed dye laser is considered to be the laser of choice for treatment of facial telangiectasias. 5 – Nd:YAG laser: The deeply penetrating Nd:YAG 1064 nm laser has significantly less hemoglobin absorption than the wavelengths of the PDL or KTP lasers. This laser can be used to treat deeper vascular lesions and spider veins up to 3 mm in size. Because of its poor coefficient of absorption by hemoglobin, much higher fluences are required to produce transmural heating of blood vessels. Nd:YAG lasers should be used with extra caution when treating vascular lesions.
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