Objective: To explore the effect and safety of fractional 1565 nm laser on white striae gravidarum (SG) in abdomen and observe the influencing factors of treatment effect. Methods: Thirty-six patients, aged 24-39 years old, were randomly divided into two groups(group A, n=16, group B, n=20): patients in group A underwent two passes of laser treatment: striae were locally scanned at moderate level energy(35 mJ/μb) with high density(300 dot/cm²), and high level energy (45 mJ/μb)with low density(150 dot/cm²)was adopted for the whole area.Group B received one pass of treatment at moderate energy with high density 35 mJ/μb, 300 dot/cm²). All patients received three laser treatments at a 6 weeks interval. Improvement of SG appearance was assessed by blinded reviewers, 3 months after the last treatment, using a percentage category scale. Meanwhile, patients satisfaction was evaluated. The impact of skin aging on laser treatment was evaluated. Patient satisfaction scores and side effects were evaluated. Results: All patients completed the overall trial. The average improvement of scores was 1.69±0.95, which contributed to a fairly good response rate of 88.89%. The patients satisfactory and very satisfactory rate was 58.3%(21/36). There was no significant difference in improvement score between group A(1.88±0.89) and group B(1.55±1.00) (P< 0.01). The operation duration of group B was shorter than group A, (29.6±4.9)min vs.(53.7±5.5)min, P<0.05. There was a moderate negative correlation between aging and laser treatment effect (r=-0.553). The abnormal color of skin(erythema and post-inflammatory hyperpigmentation) in group A lasted longer than group B, (9.17±4.03)d vs. (6.73±2.29)d, P<0.05.The pain score during treatment was tolerable, with the score of 2.61±0.76. Conclusions The treatment with fractional 1565 nm laser can improve the appearance of SG. It is more timesaving when the entire implicated area treated by one pass at moderate level energy with high density. Skin aging will discount the effect.

Photoelectric and ultrasonic technology rapid development has brought more choices for facial rejuvenation, but its prosperous clinical application forms a sharp contrast with its weak theoretical based research. Moreover, there is still no consensus on how to standardize the short-term and long-term effects of skin rejuvenation for different energy sources. This paper summarizes the application and progress of photoelectric and ultrasonic technology in facial rejuvenation in recent years, with emphasis on its characteristics and combination with other non-surgical treatments. Combining a variety of non-surgical treatments to maximize efficacy and balance the related risks is the direction of future development.

Objective: To observe the effect of monopolar radiofrequency(RF) and fractional CO₂ laser on the filler hyaluronic acid (HA) injected subcutaneously in rats. Methods: Five circular areas with a diameter of 2 cm at the dorsum of each rat were prepared for different treatment randomly: (1)HA injection group(HA). (2)HA injection+ fractional CO₂ laser treatment group(HA+ CO₂). (3)HA injection+ radiofrequency treatment group(HA+ RF). (4)0.9%NaCl+ fractional CO₂ laser treatment group(NaCl+ CO₂). (5)0.9%NaCl+ radiofrequency treatment group(NaCl+ RF). The volume of HA in group 1, 3, 4 were determined via MRI with reconstruction of Mimics Research X 17.0 before or 1, 3, 6, 12 months after photoelectric treatment. The rates of absorption of each time point and duration were calculated. Results: The mass of HA could be even recognized 12 months after treatment macroscopicly. Inflamatory cell infiltration and fibring were observed around HA in HA, HA+ RF, HA+ CO₂ group within 1 month. The fibrous capsule formed around HA, which was enhanced by RF and CO₂ laser therapy since 3 months post therapy. There was no significant difference of volume of HA among the three groups before photoelectric treatment. There was significant difference of HA volume on 12 months post treatment, HA(311.90±52.59) μl, HA+ RF(404.80±64.29) μl, HA+ CO₂(357.60±59.10) μl(P<0.01). The volume of HA received RF treatment degraded more slowly. The rate of HA absorption during 3-6 months post treatment was significantly lower than that of 6-12 months post treatment(P<0.05). Conclusions Fractional CO₂ laser and radiofrequency do not increase the degradation of HA. On the contrary, they may prolong the duration of HA injected subcutaneously in rat.