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The clinical reality of psoriasis is that there is no “typical” presentation. While research studies and guidelines for care emphasize quantifiable characteristics of disease like body surface area (BSA) involvement or Psoriasis Area and Severity Index (PASI) scores, clinicians recognize that various factors related to the disease and its treatment may weigh heavily on any given patient. Disease affecting the palms and soles, for example, may not be extensive, but the effects can be profound. Disease affecting the scalp may be little more than a nuisance to one patient, but the daily requirement of applying topical medication to the head can reduce quality of life.

While pharmacological options for treatment continue to expand and provide important treatment approaches, established therapies remain essential for many patients. Light-based therapies have witnessed some developments in recent years, with the shift away from UVA-based treatments to UVB and Narrow-band UVB and now even excimer laser delivery of UVB phototherapy.


Light-based therapies continue to be popular among patients, due to their relative safety and efficacy. 1,2

Historically, light-based therapies have earned mixed marks for convenience from patients and practitioners. For example UVB light-box therapy to treat large BSAs or targeted delivery of light to treat scalp disease may be significantly easier and more patient-friendly than the application of topicals to large areas or to hair-bearing skin. However, scheduling several-times-per-week sessions and navigating insurance and co-pays can be challenging.

The excimer laser (XTRAC, PhotoMedex) is a newer option for targeted delivery of UVB phototherapy that has helped to increase the convenience of light therapy in my practice. Compared to the exposure provided by a light box, the laser reduces the total UVB exposure for the patient and prevents irradiation of un-involved skin.

As with traditional light-boxes, targeted UVB can typically be administered by a non-physician. We have a designated technician on-staff to provide XTRAC treatments, and she maintains her own schedule, providing many opportunities for patients to present for their 15-30 minute treatment session at their convenience.

For our practice, this approach has worked well and has caused no interruption in other office operations. As a practitioner, a benefit of an office-based treatment is that I can track patient adherence, which inevitably lags over time with pharmacologic therapy for most psoriasis patients.

Targeted UVB therapy may be perceived as technologically advanced and may have appeal to some patients, thus increasing interest and possibly bolstering adherence. Additionally, many patients welcome a device-based in-office procedure that gives them a sense that something is “being done” to help their condition. This can be a psychological benefit that again contributes to treatment adherence.

I prescribe concomitant topical prescription therapy for all my excimer laser patients. In my experience this combination approach provides for better treatment outcomes than monotherapy. The speed and efficiency of the combination approach in many cases seems to encourage adherence with the regimen; Patients who see results quickly are incentivized to continue treatment. Plus, at every XTRAC treatment, we have the opportunity to remind patients to be compliant with their medications at home.

We educate patients at the start of the treatment program that laser treatment is provided at specific intervals for a given period of time and that eventually topical therapy will be used as maintenance or for initial management of flares. Many patients who achieve clearance with the excimer laser treatment remain relapse free for several months or more before requiring re-treatment with the laser.


Having used traditional light boxes in my practice for many years, I was somewhat skeptical about using excimer laser therapy for psoriasis. However, over time I have been convinced of the benefit and now have three lasers, one in each of my offices. I have made changes to my practice to accommodate the technology, though these have been relatively minor. In addition to training the technician and creating a separate scheduling system for her, we also assigned a billing staff person to handle insurance questions, gain any required pre-authorizations for coverage and/or any referrals needed related to this treatment. PhotoMedex also provides support in this regard, helping patients determine whether the excimer laser treatment is covered. Increasingly, insurance providers are expanding coverage.

We have used internal marketing to educate existing patients (including those who may not have been to the office for several years) that we offer XTRAC, and we provide educational information throughout the practice. We also have new patients who come to us specifically because they learned that we offer the treatment. PhotoMedex has a large-scale marketing program in place in many major markets that supports and promotes the laser by name and the conditions it treats. PhotoMedex also staffs call centers that helps direct interested and eligible patients to providers in their area. They will also prescreen potential patients eligibility and confirm insurance coverage.


The XTRAC laser provides a targeted delivery of UVB energy to the skin, and is ideally suited for discrete areas of involvement. The laser is also especially suited to successfully perform scalp treatments. However, I have increasingly used this therapy for patients with larger BSA involvement. I also rely on this laser therapy for patients with steroid phobia, who simply will not use a mid-to-high potency steroid to calm psoriasis. Excimer laser therapy is not appropriate for all patients, including those on photosensitizing drugs or those with a history of melanoma. Patients with known sensitivities to light can be treated conservatively to minimize adverse events.

Dr. Serure is a board certified dermatologist in Long Island, NY with offices in Commack, Smithtown and Hampton Bays. She serves as the chairperson for the Department of Dermatology at St. Catherine of Siena Medical Center.

  1. Chen X, Yang M, Cheng Y, Liu GJ, Zhang M. Narrow-band ultraviolet B phototherapy versus broad-band ultraviolet B or psoralen-ultraviolet A photochemotherapy for psoriasis. Cochrane Database Syst Rev. 2013 Oct 23;10.
  2. Almutawa F, Alnomair N, Wang Y, Hamzavi I, Lim HW. Systematic review of UV-based therapy for psoriasis. Am J Clin Dermatol. 2013 Apr;14(2):87-109.
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