Advances in Treating Leg Veins

09/04/2008
L eg veins are an extremely common problem. A recent epidemiologic study found that 80% of the population had reticular veins or telangiectasia. Another study revealed that approximately 50% of women developed leg veins by the age of 50. In addition, 50% of patients experienced symptoms associated with their leg veins. Since the 1980s, port wine stains and facial telangiectasia have been successfully treated with lasers. These lesions are easily treatable with lasers because the vessels comprised within them are generally superficially located, monomorphous and of small diameter. Vessels in port wine stains are usually 20 to 100 microns in diameter, and facial telangiectasia range from 50 to 200 microns. However, leg veins are heterogeneous vessels in a number of ways. They vary in size, relative state of oxygenation, and depth within tissue. For these reasons, leg veins have proven to be much more difficult to target with lasers. Despite these challenges in treating leg veins with lasers and other light-based devices, advances in the technology have led to improved results. This article will review the devices presently being used to treat leg veins, including: • pulsed KTP lasers (532 nm) • pulsed dye lasers (585 nm to 600 nm) • intense pulsed light sources (585 nm to 600 nm) • the near-infrared lasers: • alexandrite (755 nm) • diode lasers (800 nm, 810 nm and 940 nm) • 1064 nm Nd:YAG lasers. New Advances in Technology The newest trends in treating leg veins include applying longer millisecond pulse durations, using deeper penetrating wavelengths and advanced skin cooling techniques. • Longer pulse durations. This precludes the development of purpura, and enables slow, even heating of larger diameter vessels. • Longer wavelengths. These penetrate more deeply and enable treatment of larger diameter vessels that are situated more deeply. The 1064 nm Nd:YAG lasers can penetrate skin down to 5 mm in depth. • Skin cooling techniques. An array of skin cooling techniques help protect the epidermis and allow the safe use of significantly higher energies without harming the skin’s surface. In order to successfully treat leg veins with lasers, the endothelial wall must be irreversibly damaged by the laser energy. Hemoglobin within the red blood cells of the vessels is the actual target for laser light. Wavelengths of light are chosen for vascular indications based on their preferential absorption by hemoglobin and relatively low absorption by melanin, the other major cromophore in skin. Light energy is converted to heat energy within the targeted structure. The pulse duration or exposure time is determined based on the ability to generate enough heat to passively diffuse through the endothelial wall, but not to adjacent tissue structures within the dermis. Here are some insights into the following lasers and their capabilities in treating different types of leg veins. KTP Lasers Pulse KTP lasers have a wavelength of 532 nm, and utilize a range of pulse durations from 1 ms to 200 ms, depending on the manufacturer. At this wavelength, there is excellent hemoglobin absorption, but melanin is also strongly absorbed. The KTP lasers should, therefore, not be used on suntanned individuals or patients with darker skin types because of risk of pigmentary changes. KTP lasers are most effective for vessels less than 1 mm in diameter. Studies performed using pulsed KTP lasers have shown good clearance rates. A recent study performed by Dr. Robert Adrian found that 63% of patients had greater than 75% clearance with up to three treatments. Another paper by Dr. Eric Bernstein indicated greater than 75% clearance in two treatments for telangiectasia up to 1 mm in diameter. With these lasers, a single pass of contiguous pulses is applied along the length of the vessel. The endpoint is spasm of the vessel or blanching. Additional passes can be performed until blanching or vessel edema occurs, but pulse stacking should be avoided. The Aura (Laserscope) and VersaPulse system (Coherent/ESC) lasers are equipped with a sapphire cooled laser tip that provides epidermal cooling during treatment while enabling excellent visualization at the treated vessels. I’ve demonstrated that the application of a cold hydrogel to the skin during treatment permits easier handling of the laser handpiece and decreased side effects including pain, edema and erythema. Pulsed Dye Laser A long-pulsed 1.5 ms pulsed dye laser from Candela was the first laser specifically developed for the treatment of leg telangiectasia, and a similar device is available from Cynosure. These lasers can be tuned from 585 nm to 600 nm, and are used at a pulse duration of 1.5 ms. These wavelengths provide excellent hemoglobin absorption, and the lasers are effective in treating isolated telangiectasia up to approximately 1.2 mm in diameter. Post-treatment purpura lasting approximately 7 to 10 days is produced after treatment, and transient hyperpigmentation may occur with an incidence of 20% to 40%. Since melanin absorption is relatively high at this wavelength, there is a risk of pigmentary change in dark or suntanned skin. Intense Pulsed Light (IPL) The intense IPL is a pulse flashlamp device that was originally developed as the Photoderm by Energy Systems Corporation (now Lumenis) and is not technically a laser — it emits a spectrum of light from 515 nm to 1200 nm. But, like a laser, it uses high fluences and short, pulsed exposure times. There are a wide variety of IPL systems now available from many manufacturers. This device has been used for the treatment of leg veins up to 2.0 mm in diameter. It is particularly useful for the treatment of post-sclerotherapy telangiectatic matting. Like other visible light devices, treatment should be limited to fair-skinned individuals without suntans. Patients treated with pulsed dye lasers at pulse durations <6 ms, will develop purpura, which may last approximately 1 week. Overnight compression is useful, even for smaller telangiectasia. Sun exposure should be avoided to prevent the development of post-inflammatory hyperpigmentation. Near-Infrared Lasers Near-infrared lasers have recently been explored for the treatment of leg veins. The longer wavelengths provide increased tissue penetration, enabling effective treatment of larger diameter vessels at deeper locations in the dermis and subcutaneous tissues. Lasers applied to leg vein treatment include the alexandrite (755 nm), diodes (800 nm, 810 nm and 940 nm) and the Nd: YAG. • Alexandrite lasers. This wavelength provides much deeper penetration than the KTP and pulsed dye lasers. These lasers are effective for treating telangiectasia, venulectasia, reticular veins, and foot and ankle vessels. Melanin absorption also occurs at 755 nm, particularly with the high fluences utilized. Treatment is therefore limited to patients with phototypes I to III without evidence of a suntan in order to avoid epidermal damage. Telangiectasia >0.3 mm in diameter are effectively coagulated with the application of higher fluences to compensate for the lower absorption coefficient of hemoglobin. The best results are achieved with pulse durations of 3 ms to 5 ms and fluences higher than 50 J/cm2. My own research has shown that reticular veins can also be removed using these parameters, typically with one treatment session. Dr. David McDaniel studied the Cynosure Apogee and found about 48% clearance after three treatments using relatively low fluences — 20 J/cm2. We studied the Candela GentleLASE system with higher fluences — 60 to 80 J/cm2 with a 3 ms pulse duration and found that 65% of patients with veins up to 2 mm in diameter had greater than 75% clearance after one treatment. With the GentleLASE system, the epidermis is protected by a cryogen cooling system (the Dynamic Cooling Device). • Diode lasers.The 800 nm and 810 nm diodes, which are used for hair removal, as well as a 940 nm diode laser (which has been studied in Europe) have been shown to effectively treat lower extremity vessels. Dr. Christine Dierickx first studied the diode laser for leg vein treatment and found that, in up to three treatment sessions, 42% of patients showed greater than 75% clearance. Her studies were performed using relatively low fluences — 15 J/cm2 to 40 J/cm2. Dr. Peter Kaudewitz recently reported 1-year follow-up results following treatment of telangiectasia with a 940 nm diode laser. Small spot sizes, 0.5 mm to 1.5 mm in diameter, and fluences in the 300 J/cm2 to 400 J/cm2 range were used. Seventy-five percent of patients had greater than 75% clearance 1 year after treatment. Only skin types I to III were tested. Larger vessels would be expected to respond well to this wavelength using larger spot sizes and skin cooling techniques. With the diode lasers, as with the other systems, the veins are treated with a single pass of contiguous laser pulses. The 940 nm diode laser is not equipped with a skin cooling device, so ice cubes were applied for post-treatment cooling. Nd:YAG Lasers The newest wavelength that’s been applied to the treatment of leg veins is the 1064 nm Nd:YAG laser. It provides the deepest penetration of all the near-infrared wavelengths. It’s a versatile wavelength because smaller diameter vessels such as telangiectasia and venulectasia, as well as larger, deeper vessels such as reticular veins and foot and ankle vessels and tributary varicosities can be treated. The caveat is that treatment of these larger veins can be quite painful and vessel resolution may be prolonged compared to sclerotherapy treatment. Treatment has been shown to be safe in skin types I to IV. Cooling is essential with this wavelength because of the high heat generation within the dermis. Drs. Robert and Margaret White published the first report using the 1064 nm lasers for leg vein treatment, and they achieved approximately 75% clearance 3 months after one treatment session, treating a range of vessels up to 3 mm in diameter. Dr. Neil Sadick has reported 1-year follow-up using the VascuLight (Lumenis) system and demonstrated greater than 75% clearance in 64% of patients. I recently published a report with Drs. Omura, Dover and Arndt using the Coolglide laser (Altus) to treat reticular veins. We found two-thirds of the patients had >75% clearance at 3 months after one treatment. The treatment technique with the Nd:YAG lasers is similar to the other devices. Smaller diameter vessels are treated with smaller spot sizes and higher fluences; larger spot sizes and lower fluences are used for venulectasia and reticular veins. Treatment of larger veins often requires the use of atopic anesthetic cream because of treatment-associated discomfort, particularly with deeply penetrating Nd: YAG lasers. Reticular veins may develop intravascular coagula that require extraction, as is performed following sclerotherapy treatment. Compression therapy is used for 2 to 3 days after treatment of larger vessels. Laser Treatment Compared to Sclerotherapy A recent study by Dr. Brian Zelickson demonstrated equivalent clearance rates and side effect profiles when matched patches of vessels were treated on the bilateral legs with sotradechol sclerotherapy and either a 755 nm alexandrite laser or a 1064 nm Nd: YAG laser. Such studies suggest that laser therapy is a reasonable first-line treatment option in the appropriate patients. Multiple Modalities Reap the Best Results An ideal therapy for leg veins would provide 100% clearance, have no side effects, and would be painless. However, this type of treatment currently does not exist, be it sclerotherapy or any laser or light source modality. For best results, we often require multiple modalities. A given individual may require a combination of phlebectomy, sclerotherapy and laser treatment for optimum clearance of their leg veins. Sclerotherapy remains the gold standard for telangiectasia, venulectasia and reticular veins; surgical modalities are the mainstay for varicosities and junctional reflux. Primary indications for laser therapy include telangiectatic matting, isolated telangiectasia, the very fine pink vessels that are difficult to treat with sclerotherapy, patients who have failed sclerotherapy, and patients who are needle-phobic. Foot and ankle vessels are an excellent indication for laser therapy to avoid risk of skin necrosis associated with retrograde flow of sclerosant agents. Lasers and light sources are playing a greater role in the treatment of leg veins, and, in the proper setting, achieving results comparable to conventional methods without an increased risk of adverse effects.