Vascular skin lesions have been treated with pulsed dye lasers with pulses as long as 0.5 milliseconds, and mechanically gated continuous lasers with pulses as short as 30 ms. Until recently, the pulsewidth range from 0.5 ms to 30 ms has not been explored. For the Phase I work of the project, Laserscope developed a KTP laser at 532 nm (green) that was pulsed from 1 to >30 ms, and very encouraging animal studies were conducted at Wellman Labs, MGH, showing that this pulsewidth range may be very important to treat vascular lesions, as was previously predicted from theoretical modeling. For Phase II of this project, this KTP laser will be used in clinical evaluation for portwine stains and telangiectasia. A dye laser will be added to this KTP laser to give millisecond pulses tunable from 520 to 630 um. Animal studies and clinical evaluation will follow at Wellman labs for treatment of vascular lesions with this tunable laser. The output of this laser is also Q-switched and can produce pulses at 532 nm with a pulsewidth of 150 ns, as well as pulses at 1064 nm with about 50 ns pulsewidth. These micropulses will be used to treat pigmented lesions and possible tattoos. A mechanical scanner will also be developed to enable very uniform treatment of vascular as well as pigmented lesions. If successful, a single laser will then be able to treat vascular and pigmented lesions as well as tattoos. PROPOSED COMMERCIAL APPLICATION: Family of Dermatology Laser Products from Laserscope: 1. Pulsed KTP Laser (532 nm), 1 to 20 ms, with scanner for vascular lesion. 2. Same laser, with tunable dye laser from 570 to 630 nm added. 3. Same laser, with features to treat pigmented lesions and tattoos added. 4. Family of scanners with above lasers.