Randomised split-face study of two fractionalised resurfacing lasers to treat photoageing

Post-procedure care

For the areas treated with the ActiveFX, subjects were instructed to maintain a barrier coating of Vaseline (petroleum jelly) using a tongue depressor and to continue doing this every few hours to prevent direct contact between the treated tissue and air during healing. They were also instructed to wash the treated area with cool water, 2% dilute vinegar, or Cetaphil if required. All patients received Omnilux 633 nm light.

In patient CM (Figure 4) the author used dilute vinegar soaks (one teaspoon of distilled white vinegar to two cups water) applied over a layer of Vaseline every few hours postoperatively, but only because the patient requested multiple passes. The patients were shown demonstration photographs of other patients to explain that the treated facial areas will be pink–red for the first 2 days post-treatment, before turning a darker red to purple colour. They were also warned about the possibility of a herpetic outbreak on the third day, and shown photographs of how this would appear.

The patients were reviewed at 7–10 days postoperatively, during which time the treated areas of the face had mostly returned to normal, although the neck sometimes remained erythematous. Outbreaks of herpetic infection were reviewed on an almost daily basis, and patients were prescribed Famvir 750 mg three times per day during this period. A topical steroid (1% Hydrocortisone) was applied to two patients for continual itch, possibly a result of Vaseline sensitivity.

Skin biopsies and histology

Skin biopsies were obtained from five of the patients intraoperatively from each side, after one laser pass, and at 3 months postoperatively. Lesion penetrative dimensions were assessed histologically using haematoxylin and eosin. Blinded histological examination of laser-treated halves was performed to determine the amount of tissue ablation, residual thermal damage, inflammation, and new collagen synthesis.

The patients received a single fractional ablative CO2 treatment with the ActiveFX device on one side of the face, and the DEKA SmartXide DOT device on the other. Micrographic analysis showed a 30% increase in new collagen on the CO2 treated side and a 15% increase of new collagen on the other side.

These slides were reviewed by dedicated skin histopathologists Professor Kieran Sheahan and Dr Tom Crotty, Consultant Histopathologists, St Vincent’s University Hospital, Dublin, Ireland.

Case studies

Photoageing

In Figure 2, the patient was a 59-year-old Caucasian female with a ‘normal’ level of photoageing. She had a history of herpes simplex and was prescribed Famvir 750 mg once daily.

The left side of her face was treated with the ActiveFx: energy 125 mJ, rate 125 Hz, CPG 3/5/4. The right side was treated with the SmartXide: power 30 W, Dot mode spacing 400 μm, dwell time 500 μs with two passes under the eye. The ActiveFx settings for the neck were: energy 90 mJ, rate 125 Hz, CPG 3/5/1.

On the third day post-treatment she developed full facial herpes and some truncal spots and prescribed Famvir 750 mg three times per day for 7 days.

Perioral rhytides

In Figure 3, the patient was a 72-year-old Caucasian female who had moderately severe facial rhytides, especially in the perioral area. She also had a moderate level of photoageing.

The left side was treated with the ActiveFx: energy 125 mJ, rate 125 Hz, CPG 3/5/3. The right side was treated with the SmartXide: power 30 W, Dot mode spacing 400 μm, dwell time 1 ms, with two passes over each side.

Although her rhytides were equal initially, the patient and author felt the ActiveFx side responded best with regard to the reduction of coarse lines. Scoring for fine lines dropped from 3 to 1 for both lasers at day 30. Scoring for perioral coarse lines dropped from 4 to 2 for ActiveFx, and 4 to 3 for SmartXide at day 30.

Periorbital rhytides

In Figure 4, the patient was a 53-year-old Caucasian male with bilateral periorbital rhytides. He had had a previously poor response to Isolagen fibroblast transplantation in this area. He also had a moderate level of photoageing.

The right eye was treated with the ActiveFx: energy 100 mJ, rate 125 Hz, CPG 3/5/2. The left eye was treated with the SmartXide: power 30 W, Dot mode spacing 200 μm, dwell time 500 μs, with two passes under the eye.

Periorbital rhytides

In Figure 5, the patient was a 39-year-old Caucasian female with moderate bilateral periorbital rhytides. She had had previous treatment with Dysport bilaterally 2 months prior to this procedure.

The right eye area was treated with the ActiveFx: energy 100 mJ, rate 125 Hz, CPG 3/5/2. The left eye area was treated with the SmartXide: power 30 W, Dot mode spacing 400 μm, dwell time 500 μs with two passes.

Discussion

Although the two CO2 lasers initially appeared to produce equivalent clinical improvement of lesions and rhytides, there was a marked difference in new collagen formation noted at 3 months. Re-epithelialisation after Omnilux 633 nm light occurred in all laser-treated areas at day 5, and this appeared to be similar for both lasers. The mean duration of re-epithelialisation was 5.7 days after resurfacing (range 4–9 days). This appeared to be in keeping with previous studies11, and was quicker than a similar study the author had performed in 2007 without the application of post-procedural phototherapy. No patient reported a crusting effect on their face after 6 days. All patients usually received only one pass with both laser devices. However, in some cases, two or more passes were performed — if deemed necessary — to allow a better overall result for the patient or cover overlap and fill in missed edges.

Residual erythema remained in a small group for a period of 14 days, but this was mostly in the herpetic group. Postoperative erythema was most intense in the areas treated by SmartXide whenever the dwell time was increased to 1 ms. This effect was also noted with the ActiveFx at the energy level above 125 mJ. Most patients said they could use camouflage make up (e.g. GloMinerals®) to cover the erythema on days 4–5. No significant gender differences in the duration of re-epithelialisation, erythema or in the histopathology changes were noted.

The global score for photoageing for both devices improved from 13.8 at baseline to 9.6 at day 30. The score for fine lines was the most significant reduction, dropping from 3.6 at baseline to 1.4 at day 30. The score for sallowness was the most difficult to interpret at day 30 as patients still had some mild erythematous effect. Scores for reduction of coarse wrinkles (3.2 at baseline to 2.2 at day 30) were also difficult to interpret in this heterogeneous age grouping, with older patients requiring the deeper penetrating ‘harder’ MaxFx (also from Lumenis) rather than the ‘softer’ ActiveFx, and it is apparent that Lumenis are presently working on a combination therapy to address this.

The mean pain sensation felt during the treatment was 2.7, in keeping with other studies1. The author noted that most patients do not feel much pain with the ActiveFx if the topical anaesthetic is applied 1 hour before treatment, or until the settings are above 100 mJ. Some patients required ice-packs owing to a mild ‘burning’ effect after the procedure, but none required analgesia to take home.

Post-inflammatory hyperpigmentation (PIH) was not noted in any of the patients. Seventeen patients were classified as Fitzpatrick skin types I and the remaining four as type II. Two patients sustained a global facial herpetic infection. No patient experienced any adverse reaction to laser skin resurfacing outside herpetic infection, and 92% of patients were satisfied with their final aesthetic outcome. The mean patient age was 53 years (range 43–74 years). A small number of patients (< 3%) received full facial herpes. A similar study in 2007 showed levels of < 12%, especially with the ActiveFx. This number fell dramatically after changing prophylactic anti-viral protocol from Famvir 750 mg daily to Valaciclovir 500 mg twice daily for 1 week.

All skin biopsies in this study show the effect of thermal treatment with thermal coagulation of epidermis and superficial dermis in a depth ranging 85–700 µm. This was especially seen with the ActiveFx going below 700 µm. A number of studies show that the zone of residual thermal (coagulative) damage can extend a further 20–120 µm, depending on the particular laser variables used14–16. This was particularly evident in image C, in which the SmartXide thermal effect appears to be more diffuse than focal. As CO2 lasers differ in their biophysical properties, their documented depth of histological ablation and thermal effects vary15, 16.

Limiting the depth of penetration also decreases the risk of scarring and permanent pigmentary alteration. However, during the period of the study, the author became quite comfortable using the SmartXide with longer dwell time, reduced spacing and selective use of double passes, particularly in the upper lip and lateral periorbital areas of some patients outside the study to achieve better aesthetic effect. The longer dwell time, albeit with reduced spacing, could achieve deeper collagen stimulation to increase the rejuvenative effect. These parameters are for Fitzpatrick skin types I–III. In general, thinner periorbital skin usually requires fewer laser passes, but the author felt comfortable enough to double pass patients with the SmartXide in this area.

Conclusions

Laser resurfacing technology is continually changing and the type of laser purchased and the settings used by the operator is dependent on financial considerations, skin type, patient age, and thickness of epidermis and dermis to be treated. This means that an experienced operator can adapt the depth of penetration and thermal dwell time dependant of the laser, and depending on whether forehead, chin, nose or cheek requires treatment. In keeping with evolving computer design, Deka introduced a new stack setting software for the SmartXide DOT laser while this study was ongoing. As the original study had to be repeated owing to an ActiveFx mirror malfunction, it was felt that the new stacked settings with the SmartXide laser could achieve a deeper papillary dermal effect, and therefore increase neocollagenesis.

Since the end of this study, Deka has introduced the new SmartXide DOT HP superpulse technology, which is a step up from their previous S-pulse shape, allowing one to better control the depth of penetration. Preserving all the features of the 30 W SmartXide DOT, but with 60% more power, the new SmartXide DOT HP allows practitioners to target deeper tissue with a single pulse. It also avoids the need for pulse stacking and spares patients from uncontrolled lateral thermal damage. They have also introduced the SmartXide DOT/RF, merging fractional CO2 and radiofrequency on a multidisciplinary C02 laser platform.

Despite this, the Lumenis UltraPulse ActiveFx is considered a much superior laser. It has six-times the power of most CO2 lasers (225 mJ of energy) and four-times the depth of penetration of any other CO2 laser (up to 4 mm). It also has 34 FDA-cleared dermatology and plastic surgery indications, an optimal ablation/coagulation ratio with advanced patented technologies, and has adapted to support a wide spectrum of aesthetic and surgical capabilities. This was very obvious when the operator had to treat a giant congenital nevus at higher settings.

Newer additions to the Lumenis UltraPulse include DeepFX for the treatment of profound wrinkles, with a 0.12 mm spot size; TotalFX, which provides scar treatment, improved skin texture, and resolution of fine lines and wrinkles, with 1.3 mm and 0.12 mm spot sizes; and SCAAR FX, ‘Synergistic Coagulation and Ablation for Advanced Resurfacing’.