Stretch marks: Using lasers, light devices for treating striae

April 1, 2008

Striae distensae are a very common post-pregnancy complaint in women, yet they frequently occur in other situations as well. Obesity, rapid weight gain or weight loss, puberty or weightlifting can also cause striae. Chronic use of topical steroids, especially in intertriginous or Cushing's syndrome also will lead to stretch marks.

Key Points

Striae distensae are a very common post-pregnancy complaint in women, yet they frequently occur in other situations, as well. Obesity, rapid weight gain or weight loss, puberty or weightlifting can also cause striae. Chronic use of topical steroids, especially in intertriginous or Cushing's syndrome also will lead to stretch marks.

Some data suggests that up to 90 percent of pregnant women will develop striae, and up to 70 percent of adolescents (females more than males). With this high of an incidence - and no cure - we can definitely expect to see more research and development in this area.

Histologically, striae demonstrate atrophy of the epidermis with flattening of the rete ridges. The dermal collagen is densely packed, similar to a scar. Elastic fibers are thin and fragmented.

Elastic skin may be less likely to tear with stretching. Regular use of moisturizers including oils may help achieve these results. None of these preventive measures have been proven in clinical trials, though several, including cocoa butter and shea butter, have had a reputation for this purpose.

In my opinion, true prevention does not exist, leaving much of the focus on treatments.

Treatments for stretch marks are paramount, but most are based on theory and anecdotal reports, and not true science.

Topically applied retinoids have been shown to clinically improve the appearance of early striae. Tretinoin .05 percent to 0.1 percent should be applied nightly, as tolerated. If no desquamation ensues, application can be increased to twice a day.

For those patients who cannot tolerate tretinoin application without side effects, combination with a lipid containing moisturizer may increase tolerability.

Other topical medicaments for treatment of striae include growth factor creams, peptide products, retinols, trichloracetic acid peels and microdermabrasion.

Many of the creams marketed for striae contain "proprietary proteins and peptides" which can run from $40 to $240 for a 6-ounce tube - per ounce, the cost of American caviar. Months of treatments may be necessary for results, resulting in a possibly large financial burden for no guaranteed improvement.

As our laser armamentarium has become more sophisticated, is there now a role for these devices in the treatment of striae?

Let's take a systematic approach to the problem. Since the histologic changes in striae occur in the epidermis and dermis, a deep-penetrating laser would be ideal. In addition to penetration into the dermis, restructuring and thickening of the epidermis, plus a remodeling of both elastin and collagen fibers, would be necessary.

These are many of the same goals of laser treatments for photoaging. The erythema associated with striae rubra would also need to be amenable to this wavelength. The device must also be safe for use off-face, since most striae occur there. It may be that one device is not enough to eliminate these lesions. Also, striae rubra may end up responding differently than older striae alba lesions.

Lasers have been used in striae since McDaniel reported the use of the pulsed dye laser (PDL) on stretch marks in 1996. Originally lasers, like the PDL, had their best success at treating striae rubra.

The erythema in the stretch mark was used as the chromophore for PDL's 585/595 nm wavelength with much success. Erythema of the striae was reduced in several studies, improving the cosmetic appearance of the lesion, but not eliminating it.

Erythema in striae responds best to low-fluence treatments using PDL with a larger spot size, perhaps correlating with deeper laser penetration. Still, little to no response at all was seen for the textural component of the lesions.

Current reports on treatment for striae distensae include use of fractional resurfacing devices including Fraxel Re:store (1550 nm) (Kin, 2008), RF + 585 nm pulsed dye (Suh, et al, 2007), eximer laser (Goldberg, et al, 2005) and intense pulsed light (IPL)(Hernandez-Perez, et al, 2002).

In most studies, pulsed dye lasers were effective at reducing erythema of striae rubra, but not effective at improving the appearance of striae alba (Jimenez, et al, 2003).

When used in combination with a radiofrequency device (Thermage®), a histologic increase in collagen was noted, with 59 percent of patients noting a "good" improvement in elasticity.

Eximer lasers (UVB) showed some promise at repigmenting striae alba, but as expected, no improvement in the textural component of the stretch mark.

Nonablative devices, such as the Smoothbeam (1450 nm, Candela), have clinically not been very useful, though they do increase collagen histologically.

Fractional resurfacing offers a possible mechanism to remedy many of the associated components of a stretch mark. The ability to resurface off-face, which in the past was not possible with classic resurfacing devices, may offer a new weapon in the war against stretch marks.

Epidermal turnover and increased collagen production and elastin remodeling, make these devices almost ideal for striae and scars. There are only few published studies to date on striae and fractional resurfacing.

A study using fractional resurfacing (Fraxel Re:store, Reliant) on six patients showed both clinical improvements in melanin and erythema indices, and also elasticity (Kin, et al, 2008).

Histologically, an increase in collagen and elastin deposition was visualized, as well as an increase in epidermal thickness. These devices are only moderately effective at removing erythema, as their target is water and not hemoglobin.

As we have seen in our clinic, these devices may be more effective on striae alba than striae rubra. Also, combination with a PDL prior to fractional resurfacing for striae rubra may yield the most impressive results.