Evaluation of a non-ablative, fractional 1565 nm laser for the improvement of striae distensae albae.

BACKGROUND AND OBJECTIVE: Striae distensae (SD) represent therapeutically challenging forms of dermal atrophic scarring. In addition to topical ointments, medical needling and various energy-based devices, non-ablative fractional lasers have been suggested for their improvement. However, objective evaluations of their efficacy are widely missing. In this study, we aimed to assess the clinical improvement of SD albae after three treatments with a non-ablative fractional 1565 nm Er: glass laser by employing three-dimensional analysis and several questionnaires. METHODS: A total of 16 Caucasians suffering from SD albae were included in this prospective study. Every patient received three treatments - one every 4 weeks - using a non-ablative, fractional 1565 nm laser (two passes: 300 µbeams/cm2 , 40 mJ inside the SD; 150 µbeams/cm2 , 50 mJ inside the SD and within the surrounding area). Questionnaires (DLQI, POSAS), digital photography and three-dimensional analysis employing PRIMOS® software and VECTRA® camera system were taken at baseline, 1 and 6 months after the last treatment. RESULTS: Evaluation of objective measurements at 6-month follow-up (FU) showed a significant reduction in depth of atrophic lesions by 31.7% and less skin irregularities with Smax at baseline of 621.2 µm decreasing to 411.6 µm (P < 0.01, respectively). Improvement in objective measurements was supported by significant changes in patients' rating of skin appearance. POSAS patient total score declined from 33.5 points to 17.5 points throughout the study (P < 0.001). From baseline to 6-month FU, patients' life quality improved by 68.0% (DLQI score). Procedures showed no lasting negative side-effects and little to no down time. CONCLUSION: The use of a fractional non-ablative 1565 nm laser represents a safe approach for the treatment of SD albae. Clinically observed improvements were supported by significant data from objective measurements. The results achieved at 1-month FU represented at 6-month FU, showing stable clinical improvements.

Investigation on radiofrequency and laser (980 nm) effects after endoluminal treatment of saphenous vein insufficiency in an ex-vivo model.

OBJECTIVES: An ex-vivo model for the experimental evaluation of endoluminal thermal procedures for occlusion of saphenous veins was developed. Radiofrequency obliteration (RFO) and endovenous laser therapy (ELT) were compared using this model. DESIGN: Experimental ex-vivo treatment study. MATERIALS AND METHODS: The model consists of the subcutaneous foot veins from freshly slaughtered cows which were reperfused in situ with heparinised bovine blood. The veins were treated with either radiofrequency (RFO n=5) or with endoluminal 980 nm laser light (ELT n=5) using a continuous pull-back for RFO and a stepwise illumination and pull-back protocol for ELT. Immediately after treatment perivenous tissue and veins were examined macroscopically. In a second study the same treatment parameters were used in four further vein segments with RFO (n=2) and ELT (n=2). These vein segments were examined microscopically in HE-stained histological sections. RESULTS: Induration of the vessel wall and contraction of the vessel lumen were observed after RFO. Laser treatment produced carbonised lesions of the vein wall. After 12-24 laser exposures these lesions often became transmural, causing complete perforation of the vessel wall. Histological evaluation after radiofrequency treatment demonstrated homogenous circular thermal tissue alteration with disintegration of intima and media structures. Histological evaluation after endovenous laser treatment showed large variations of thermal tissue effects. Tissue effects ranged from major tissue ablation and vessel wall disruption to minor effects located between laser exposures and on the opposite vessel wall. CONCLUSIONS: Our model is suitable for systematic scientific evaluation of endovenous thermal occlusion procedures. Our first results and theoretical considerations indicate that endovenous laser treatment should be modified in order to ensure controlled homogenous circular thermal damage, avoiding vessel wall perforation and damage to perivascular structures.