COSMETIC DERMATOLOGY

A primer on cosmetic dermatology—Part I

By Robin Ashinoff, MD

A dermatologist shares her expertise on the role of lasers and other increasingly popular ways to remove unsightly spider veins and unwanted hair.

Demand for cosmetic procedures has exploded over the last 10 to 15 years. And for at least that long, dermatologic surgeons have been performing a variety of cosmetic procedures that have been proved safe and effective. Picking up on this trend, a few enterprising ob/gyns are even adding aesthetic services to their practices. In this and a concluding article next month, I will review some of these procedures from a practical standpoint. In Part I, I'll first discuss eliminating spider veins through sclerotherapy, lasers and intense pulsed light, and then laser hair removal. The concluding article will address microdermabrasion, Botox injections, and soft tissue augmentation.

Sclerotherapy for spider veins

Popularly known as "spider veins," telangiectatic leg vessels are extremely common, affecting from 30% to 40% of American women and about 5% to 15% of American men.¹ Most dermatologists treat abnormal leg veins and telangiectasias that are less than 2 mm in diameter; a few treat the larger veins and saphenous varicosities. I'll focus primarily on treating small "spider" telangiectasias of the legs with sclerosing agents.

Histologically, telangiectasias of the legs are dilated venous and capillary vessels with thickened walls that—as part of a superficial vascular network—lie about 0.2 to 0.4 mm below the granular layer of the epidermis.² What causes these types of superficial vessels? There are no hard and fast scientific facts, only theories. Clinically, they're seen more often in women and seem to run in families. True varicose veins are probably due to an inherited abnormality in the deep venous or valvular systems—or both. Small telangiectasias, on the other hand, don't seem to be pressure related and most of these patients have no deep vascular or valvular abnormalities. Their greater frequency in women suggests that estrogen likely plays a role. Certainly, many patients report having developed these lesions for the first time during pregnancy or that it exacerbated existing lesions.

All sclerosants work by injuring the vessel's endothelial lining (Table 1).^3-7 Some sclerosants—detergent agents, for example—directly necrotize the endothelium, while others work by osmosis, which more gradually destroys that layer.⁸ This causes thrombosis and then organization of the thrombus. Some vessels spontaneously recanalize—an outcome we do not want to occur—while others scar down and become invisible, which is the goal of such therapy.

TABLE 1
Common sclerosing agents

Choosing sclerosing agents. A variety of sclerosing agents are used to treat telangiectasias. I use hypertonic saline, 23.4% or 11.7%, which is approved by the FDA as an abortifacient but not as a sclerosing agent (see "My sclerotherapy procedure"). Highly effective, the advantages of hypertonic saline are its low cost and the absence of the allergic reactions that can occur with some synthetic sclerosants. One drawback is that hypertonic saline causes a burning sensation upon injection and can also cause some cramping of the adjacent muscle. In addition, if this agent is infiltrated, it can lead to ulceration and sloughing of the overlying skin. We therefore advise patients that this may leave a permanent scar. Also, removal of the troubling side effect of hyperpigmentation of the overlying skin—seen in a minority of patients—may require bleaching agents, laser treatment—or both—and may last several months.

Agents available abroad. Several other sclerosants that are combinations of salt and sugar solutions are available abroad and in Canada but are not yet FDA-approved. One advantage is that they are almost painless upon injection; however, allergic reaction is possible. Sloughing of the skin is rare. A drawback to these agents is that results may be slower than with hypertonic saline. Another popular injection agent that is not FDA-approved, polidocanol (Aethoxysclerol), is used in strengths of 0.25% to 0.5% for smaller telangiectasias. Although polidocanol is less likely to cause complications like sloughing or hyperpigmentation, allergic reactions are possible.^3-8

Sodium tetradecyl sulfate (Sotradecol), a detergent agent, is FDA-approved for treating telangiectasias. The potential for hyperpigmentation and necrosis is higher than with polidocanol and there have been reports of allergic reactions, including anaphylaxis.⁸

Sodium morrhuate, a mixture of sodium salts sold as Scleromate, is used mostly for large varicose veins. It has caused several cases of anaphylaxis and necrosis.

The major complications of sclerotherapy include hyperpigmentation (which occurs in 20% to 30% of my patients) and sloughing of the overlying skin. Hyperpigmentation—which can persist for several months—likely results from a combination of post-inflammatory changes due to deposition of melanin as well as vessel rupture leading to hemosiderin streaks.⁹ Injecting around the ankles can cause edema, although thrombophlebitis after injection of these types of superficial vessels is rare. We also wrap our patients with Ace bandages to provide compression after injection, and treat the site immediately following therapy with a potent topical corticosteroid cream. Up to 5% of patients experience "telangiectatic matting"; that is, they develop a group of very small vessels adjacent to the treatment site.² Roughly 50% of the time, if physicians hold off treating the patient for several months, these seemingly idiosyncratic vessels will spontaneously disappear. If they persist, one can continue to inject them.

We do recommend that immediately after and between treatments, patients wear graduated compression hose, which seems to help with clearing.

Laser vein removal

Lasers or intense pulsed light sources can destroy endothelial cells through thermal injury. Some believe they also produce less inflammation when compared with injecting material directly into the vessel. However, many of the same side effects seen with sclerotherapy occur with laser and light sources: ulceration of the skin, hyperpigmentation, and matting.

While many years of proven efficacy and safety have established sclerotherapy as the gold standard, certain patients refuse to undergo this procedure because they fear needles or think that a laser is less painful; it is not.⁸ Several newer lasers are more applicable for treating leg vessels. They are all based on the theory of selective photothermolysis, which states that one can selectively target a chromophore within the skin and injure it—without destroying surrounding tissue—by choosing an appropriate wavelength of light and an appropriate pulse duration.¹⁰

The initial lasers used for leg veins were flashlamp-pumped pulsed dye lasers (PDLs). The original 585 nm PDL (with a 450 msec pulse duration) treats blood vessels measuring no more than 0.1 mm in diameter and those that are more superficially located in the skin.^11,12 For deeper penetration and greater thermal injury of larger vessels, however, one must use 595 and 600 nm PDLs with pulse widths greater than 1.5 msec.¹³ Although these lasers are somewhat effective, results have not been totally gratifying. In addition, intense pulsed light sources with wavelengths ranging from 500 to 1200 nm—which can vary both pulse duration and wavelength and also produce sequential pulses—have also been used to treat leg veins with mixed results.¹⁴

The reason that leg veins are more difficult than facial vessels to treat with laser is that leg veins are usually deeper within the skin and subject to more constant pressures from venous reflux in deep veins, as well as from gravitational forces. They are also larger in diameter. The pulse duration needed to destroy these blood vessels has been calculated to be in the 3- to 10-msec range.¹

When treating leg veins, one must also apply some type of cooling system to the skin so that the surrounding tissue does not suffer injury and possibly ulcerate, leaving a permanent scar or permanent hypopigmentation.

Researchers recently reported that Nd:YAG laser (1064 nm) irradiation can be efficacious in treating small reticular veins and telangiectasias on the legs.¹⁵ The longer wavelength of the Nd:YAG laser allows light to penetrate further into the dermis. The pulse duration of these longer pulsed Nd:YAG lasers are in the range of 10 to 50 msec. This study reported significant improvement in 71% of leg vessels after only two treatments.¹⁵ This Nd:YAG laser uses contact cooling and the researcher used postoperative ice packs to limit surrounding tissue injury. In this particular study, however, more than 60% of patients suffered from postinflammatory hyperpigmentation.

Other lasers that may effectively treat leg veins include the 755 nm alexandrite laser at higher fluences and small spot sizes with a pulse duration of 3 msec or longer. A drawback is that it may also cause a significant inflammatory reaction, purpura, and matting.¹⁶ One study found that the super-long-pulse 810 nm diode laser may also give unpredictable results in treating leg veins.¹⁷

Lasers are continuing to become more effective in selective treatment of leg veins; however, most of the patients in my personal practice receive sclerotherapy for their leg veins. At times, I've treated matting—very-small-caliber vessels that cannot be cannulated—with some of the PDLs, and have seen improvement of these types of small vessels.

Laser hair removal

Since the FDA approved the first hair removal laser more than 10 years ago, the subsequent development of lasers for this purpose has been explosive (Table 2). The advantage of laser hair removal over conventional treatment, such as shaving, waxing, and chemical depilatories, is the ability to effectively treat a very large area in a relatively short time with few side effects. In addition, patients are advised that even if they do not necessarily have total or permanent hair removal, the regrowth is almost always thinner and lighter than the original hair. The hair becomes much more like vellus hair.¹⁸

TABLE 2
Some available hair removal lasers

To fully understand laser hair removal, one must have a basic understanding of the anatomy and physiology of hair. Hairs are composed of three parts; the hair bulb, the isthmus, and the infundibulum (Figure 1). The matrix cells that produce the hair shaft are within the bulb and the bulb is within the dermal papilla. The infundibulum is the part of the hair follicle from the opening on the surface of the skin to where the sebaceous duct enters the hair follicle. The region of the hair follicle from the opening of the sebaceous duct down to where the arrector pili muscle inserts into the hair follicle is called the isthmus. It is thought that in order to achieve damage to the hair follicle, one must damage not only the bulb but also the area of interface with the arrector pili muscle, which is also referred to as "the bulge."

Hair follicles go through three phases of growth; anagen (active growth); telogen (the resting state); and catagen (involution). The longer the duration of the hair follicle's anagen phase, the greater the length of the hair, because of the longer growing period.¹⁷ More than 80% of our hair follicles are in anagen at any one time while the remainder are either in telogen or catagen phases. For hair removal to succeed, it's thought that targeting the bulge—as well as the dermal papilla containing the matrix cells—is necessary. It's also thought that the stage of the hair cycle might be an important factor in how well the laser will destroy the hair, because at different stages, the dermal papilla may be more superficial or more deeply located within the skin.

No one really has identified the optimal intervals for laser hair removal treatments. In my office, we tend to initially treat at monthly intervals and then when we start to see delay in hair regrowth, we spread the treatments out so they're less frequent. However, preoperative consent for laser hair removal does include a full discussion with the patient, during which we explain that results can vary, and that multiple treatments are necessary, sometimes as many as eight or nine for long-term hair delay. Not all patients will experience the same results and unfortunately there is no foolproof predictor of who will do well with these lasers.

Before beginning laser hair removal, especially on a woman with facial hair, ask the patient about the possibility of an underlying metabolic or endocrine disorder or even what medications she is taking. When appropriate, I refer patients to an endocrinologist for a diagnostic work-up. Certainly, no matter what type of laser treatment a patient is undergoing, you must speak to her to be sure she is not taking isotretinoin (Accutane)—or the newly FDA-approved generic form (Amnesteem)—which can cause hypertrophic or keloidal scarring. It's equally imperative to take a full drug history because several other drugs can be problematic. I'm reminded of a patient who was taking oral gold and then had laser hair removal. After the procedure, everywhere the laser had been applied, she had gold deposited in her skin that appeared greenish black in color. Nor should you treat patients who are tanned or contemplating getting a tan between treatments, as this will darken the overlying skin, leading to more complications.

All laser systems do cause mild-to-moderate discomfort. For those patients who find it quite uncomfortable, we use a topical lidocaine cream to treat sensitive areas. In addition, all the hairs are shaved or clipped before laser use, so that no hair is lying on the skin to absorb energy. Postoperatively, we apply ice-packs to the treated area for comfort and to cool down the skin—and usually a mid-potency corticosteroid to decrease inflammation. We also send the patient home with antibiotic ointment if she experiences any crusting or scabbing. A corticosteroid cream is given in case of any irritation that night or the next day.

Types of hair removal lasers

For the most part, the available hair removal lasers target the melanin in hair follicles. Melanin in the hair is seen in the matrix, shaft, and the epithelium of the follicle, as well as in the surrounding epidermis. Certainly, laser hair removal is more difficult and the complication rate is much higher when the adjacent epidermis is darker, compared to when less melanin is in the adjacent skin. Some of the available hair removal systems currently include the 694 nm long-pulsed ruby laser, the 755 nm long-pulsed alexandrite laser, the 800, 810, and 983 nm long-pulsed diode lasers, as well as the 1064 nm long-pulsed Nd:YAG lasers. The longer wave-length lasers, such as the Nd:YAG lasers, can penetrate 5 to 10 mm into the dermis, almost twice the reach of the 694 nm ruby laser.¹⁸

Ruby laser. These selectively target melanosomes, the intracellular organelles that make and contain melanin. After being irradiated with ruby lasers, selectively damaged pigmented hair follicles have been clearly demonstrated.^19,20 In addition, several studies in Caucasian patients have shown that the ruby laser can significantly inhibit hair regrowth even 2 years after a treatment. However, the transient complications after treatment have included hyperpigmentation in about 20% of patients and hypopigmentation in about 15%.¹⁹ Overall, we have found that it is safer to treat lighter-skinned people with the ruby laser and that multiple treatments are necessary.

The pulsed alexandrite. This laser has also been used to remove unwanted hair with minimal side effects in fair-skinned people. In our experience with an alexandrite system, patients have gotten significant hair delay for up to 2 years with very minor side effects.^21,22

The diode lasers. With their longer wavelengths of 800 nm to over 900 nm, these lasers have also produced good results with similar side effect profiles. Given the longer wavelength, however, they may be more effective in darker-skinned people, as are the longer-pulsed Nd:YAG lasers at 1064 nm.^23,24 In addition, all of the laser systems use slightly different cooling methods. The one we chose for our office uses a spray refrigerant prior to laser irradiation. Some of the other systems use cooled sapphire tips or cool water systems that decrease the temperature of the skin either before or after laser irradiation or at both times. Some other systems also require applying a cooled gel to the skin during the laser treatment.

Intense pulsed light. This system uses a Xenon flashlamp to produce an incoherent multiwavelengthed pulsed light (550 to 1200 nm) by attaching one of a series of long-pass filters, which are tailored to the patient's skin type and hair color. The pulse duration can range from 1.5 to 3.5 msec and the spot size used can either be 10 x 45 mm or 8 x 35 mm. It, too, uses a transparent gel to cool the skin during treatment.²⁵ Again, the possible complications after using this system are edema, erythema, hyperpigmentation, and blistering of the skin.

Photodynamic therapy. This method uses a combination of non-ionizing radiation with photosensitizing drugs to localize and target selective tissues. The drugs are activated by appropriately selecting the wavelengths of laser light that can selectively destroy tissue, while again minimizing damage to the surrounding tissue. These systems use 20% delta aminolevulinic acid applied topically and then irradiated with a wavelength of 630 nm. The advantage of photodynamic therapy is that it can be used in patients with a variety of skin types and hair colors. At present, long-term clinical studies are needed.¹⁸

Conclusions

In recent years, cosmetic dermatology has really taken off (as we'll see to an even greater extent in the section on Botox injections in next month's article.). While sclerotherapy is the gold standard for removing spider veins in legs, lasers or intense pulsed light sources are options for select patients. As for laser-assisted hair removal systems, a variety are currently on the market and—when used correctly—they can be quite effective, with few side effects.²⁶

REFERENCES

1. Dover JS, Sadick NS, Goldman MP. The role of lasers and light sources in the treatment of leg veins. Dermatol Surg. 1999;25:328-335.

2. Stegman SJ, Tromovitch TA, Glogau RG. Sclerotherapy. In: Cosmetic Dermatologic Surgery. 2nd ed. Chicago, Ill: Year Book Medical Publishers, Inc; 1990:277-287.

3. Ouvry PA. Telangiectasia and sclerotherapy. J Dermatol Surg Oncol. 1989;15:177-181.

4. Goldman MP, Kaplan RP, Oki LN, et al. Sclerosing agents in the treatment of telangiectasia. Comparison of the clinical and histologic effects of intravascular polidocanol, sodium tetradecyl sulfate, and hypertonic saline in the dorsal rabbit ear vein model. Arch Dermatol. 1987;123:1196-1201.

5. Carlin MC, Ratz JL. Treatment of telangiectasia: comparison of sclerosing agents. J Dermatol Surg Oncol. 1987;13:1181-1184.

6. Goldman MP, Bennett RG. Treatment of telangiectasia: a review. J Am Acad Dermatol. 1987;17:167-182.

7. Shields JL, Jansen GT. Therapy for superficial telangiectasias of the lower extremities. J Dermatol Surg Oncol. 1982;8:857-860.

8. Weiss RA, Weiss MA. Treatment of varicose and telangiectatic veins: sclerotherapy, ambulatory phlebotomy and laser. In: Narins RS, ed. Cosmetic Surgery: An Interdisciplinary Approach. New York, NY: Marcel Dekker, Inc; 2001:513-525.

9. Goldman MP, Sadick NS, Weiss RA. Cutaneous necrosis, telangiectatic matting and hyperpigmentation following sclerotherapy. Etiology, prevention, and treatment. Dermatol Surg. 1995;21:19-29.

10. Anderson RR, Parrish JA. Selective photothermolysis: precise microsurgery by selective absorption of pulsed radiation. Science. 1983;220:524-527.

11. Goldman MP, Fitzpatrick RE. Pulsed-dye laser treatment of leg telangiectasia: with and without simultaneous sclerotherapy. J Dermatol Surg Oncol. 1990;16:338-344.

12. Goldman MP, Martin DE, Fitzpatrick RE, et al. Pulsed dye laser treatment of telangiectases with and without subtherapeutic sclerotherapy. Clinical and histologic examination in the rabbit ear vein model. J Am Acad Dermatol. 1990;23:23-30.

13. Hsia J, Lowery JA, Zelickson B. Treatment of leg telangiectasia using a long-pulse dye laser at 595 nm. Lasers Surg Med. 1997;20:1-5.

14. Raulin C, Weiss RA, Schonermark MP. Treatment of essential telangiectasias with an intense pulsed light source (PhotoDerm VL). Dermatol Surg. 1997;23:941-945.

15. Rogachefsky AS, Silapunt S, Goldberg DJ. Nd:YAG laser (1064 nm) irradiation for lower extremity telangiectasias and small reticular veins: efficacy as measured by vessel, color and size. Dermatol Surg. 2002;28:220-223.

16. Kauvar AN, Loo WW. Pulsed alexandrite laser for the treatment of leg telangiectasia and reticular veins. Arch Dermatol. 2000;136:1371-1375.

17. Eremia S, Li C, Umar SH. A side-by-side comparative study of 1064 nm Nd:YAG, 810 nm diode and 755 nm alexandrite lasers for treatment of 0.3-3 mm leg veins. Dermatol Surg. 2002;28:224-230.

18. Lou WW, Kauvar AN. Laser hair removal. In: Narins RS, ed. Cosmetic Surgery: An Interdisciplinary Approach. New York, NY: Marcel Dekker, Inc; 2001:881-893.

19. Dierickx CC, Grossman MC, Farinelli WA, et al. Permanent hair removal by normal-mode ruby laser. Arch Dermatol. 1998;134:837-842.

20. Dierickx CC, Grossman MC, Farinelli WA, et al. Comparison between a long-pulsed ruby laser and a pulsed infrared laser system for hair removal. Laser Surg Med. 1998;22(S10):199.

21. Finkel B, Eliezri YD, Waldman A, et al. Pulsed alexandrite laser technology for noninvasive hair removal. J Clin Laser Med Surg. 1997;15:225-229.

22. Nanni CA, Alster TS. Laser-assisted hair removal: side effects of Q-switched Nd:YAG, long-pulsed ruby, and alexandrite lasers. J Am Acad Dermatol. 1999;41:165-171.

23. Kilmer S, Chotzen V, Calkin J, et al. Laser hair removal with the long pulse 1064 nm Coolglide laser system. Lasers Surg Med. 2000;26(S12):21.

24. Bencini PL, Luci A, Galimberti M, et al. Long-term epilation with long-pulsed neodymium: YAG laser. Dermatol Surg. 1999;25:175-178.

25. Gold MH, Bell MW, Foster TD, et al. Long-term epilation using the EpiLight broad band, intense pulsed light hair removal system. Dermatol Surg. 1997;23:909-913.

26. Liew SH. Unwanted body hair and its removal: a review. Dermatol Surg. 1999;25:431-439.

Dr. Ashinoff is Chief, Dermatologic and Laser Surgery, New York University Medical Center, Ronald O. Perelman Department of Dermatology, and Associate Professor of Clinical Dermatology, New York, N.Y.

My sclerotherapy procedure

Using a 30-G needle with a 1-mL Luer-Lok syringe, I inject up to 3 mL of hypertonic saline at one session. During the consent process, I always advise a patient that she will look worse before she looks better and that between treatments she'll likely look bruised and discolored. We tell women about the possibility of ulceration leading to a permanent scar, hyperpigmentation, and matting and also advise that multiple treatment sessions will be required for optimal results.

Using magnification of 1.5 x, I instruct the patient to lie down on the table at about a 45° angle and inject her while I am sitting. (We always pre-moisten the treatment area with 70% isopropyl alcohol so that the skin is more transparent.) I warn the patient that she'll have some discomfort, but it will be short-lived. Bending the needle to about a 45° angle, I always inject a very small amount of air to make sure the needle is in the vessel before injecting sclerosant under continuous low pressure. I continue until I see the vessel disappear.

Depending on the size of the vessel, I begin with 11.7% saline for smaller vessels. Aiming usually for the largest vessel I can see (which ideally will feed a number of adjacent ones), I inject between 0.1 to about 0.2 mL into any one area. Too large a volume of injection is more likely to cause ulceration or matting. The clinician mustn't allow the sclerosant to seep into the tissue as he or she pulls out; therefore, pulling back on the syringe can help prevent this from happening. Some physicians also keep topical nitroglycerin paste on hand and use it if they see prolonged blanching of the skin, which can be a sign of arteriolar injection, a cause of ulceration.⁸ If I do inadvertently extravasate the sclerosant, I always have some normal saline or lidocaine to inject into the area to dilute it.

After injection, the areas are massaged and we use compression over the site with Ace bandages. Vessels can be somewhat edematous, swollen, and discolored immediately after treatment. Patients return for the next treatment in about 3 to 4 weeks and are advised that three to five treatments are usually necessary. Approximately 80% of patients will get a good response after the first series of injections.⁸ However, most patients will need treatment in the future as new vessels develop.

Key points

• Among the sclerosing agents that can be used to treat "spider" telangiectasias of the legs are hypertonic saline, sodium tetradecyl sulfate, polidocanol, and sodium morrhuate.

• While sclerotherapy is the gold standard for removing spider veins in legs, lasers or intense pulsed light sources are options for select patients.

• When used correctly, a variety of available laser-assisted hair removal systems have few side effects and prove quite effective.

Robin Ashinoff. A primer on cosmetic dermatology--Part I.

Contemporary Ob/Gyn

2003;3:106-117.