Leviav A, Wolf R, Vilan A
Departments of Plastic Surgery and Dermatology, Kaplan Hospital, Rehovot, Israel.
Dermatol Online J. 2004 Oct 15;10(2):4.
In psoriasis the earliest observable electron microscopic changes are in the papillary dermis vasculature. Selective photothermolysis of the dermal vasculature using a 585-nm pulsed-dye laser (PDL) for the treatment of psoriasis was reported more than a decade ago. Although clinically effective, the pulsed-dye laser has limited practicality because of small spot size (5-10 mm) and lack of cost effectiveness. The objective of this study is to evaluate the safety and efficacy of a novel Light and Heat Energy (LHE) selective-photothermolysis system for the treatment of psoriasis. This system delivers controlled heat simultaneously with the light pulse; it has a large beam spot (55 x 22 mm) and is sufficiently cost effective to be widely used. Thirteen patients, seven with plaque psoriasis, five with palmoplantar psoriasis, and one with guttate psoriasis participated in a controlled study. Patients received two therapy regimens in parallel: LHE plus salicylic acid or salicylic-acid cream alone as control. Treatments were applied twice weekly spread evenly over 4-6 weeks. In most cases a fluence of 8.6 J/cm2 was applied. Efficacy of the treatment was assessed using the psoriasis-severity index (PSI) calculated from the investigator's overall assessment of the plaque's erythema, scaling, and induration. PSI was evaluated at baseline, at every other treatment visit, and during two follow-up visits scheduled 1 and 5 weeks following the last treatment. In eleven patients who completed the treatment regimen, the average global PSI score for the treated sites was reduced by 65 percent. In contrast, the control sites average global PSI score was reduced by only 7.4 percent. Six patients (55 %) had a significant improvement of 70-percent reduction or above in their PSI score, ten patients (91 %) had a 50 percent or above reduction; only one patient had a poor response (12.5 % reduction in global PSI). Erythema was reported in all cases and resolved within 24-48 hours. Six cases of burns were resolved within 2 days to 2 weeks following appropriate remedy. No cases of dyspigmentation were encountered. Light and Heat Energy (LHE) selective photothermolysis combined with salicylic acid appears to be a practical modality for the treatment of mild to moderate psoriasis. Patients experience discomfort that is only mild. There is no convalescence downtime. Clinical results obtained are similar to those reported with the pulsed-dye laser; however, this new system seems more suitable to be widely adopted as a treatment modality. Further followup is required to determine whether remission periods will be as long as those reported for treatment with the pulsed-dye laser.
在银屑病中，最早可观察到的电子显微镜下的变化出现在乳头层真皮血管系统。十多年前就有报道使用585纳米脉冲染料激光（PDL）对真皮血管系统进行选择性光热解来治疗银屑病。尽管在临床上有效，但脉冲染料激光由于光斑尺寸小（5 - 10毫米）且缺乏成本效益，实际应用有限。本研究的目的是评估一种新型光热能量（LHE）选择性光热解系统治疗银屑病的安全性和有效性。该系统在发出光脉冲的同时传递可控热量；它具有大光斑（55×22毫米）且成本效益足够高，可广泛应用。13名患者参与了一项对照研究，其中7名患有斑块状银屑病，5名患有掌跖银屑病，1名患有点滴状银屑病。患者并行接受两种治疗方案：LHE联合水杨酸或仅用水杨酸乳膏作为对照。每周治疗两次，均匀分布在4 - 6周内。在大多数情况下，能量密度为8.6 J/cm²。使用银屑病严重程度指数（PSI）评估治疗效果，该指数由研究者对斑块的红斑、鳞屑和硬结的总体评估计算得出。在基线、每次治疗访视以及最后一次治疗后1周和5周安排的两次随访中评估PSI。在完成治疗方案的11名患者中，治疗部位的平均总体PSI评分降低了65%。相比之下，对照部位的平均总体PSI评分仅降低了7.4%。6名患者（55%）的PSI评分显著改善，降低了70%或更多，10名患者（91%）降低了50%或更多；只有1名患者反应不佳（总体PSI降低12.5%）。所有病例均有红斑报告，且在24 - 48小时内消退。6例烧伤在适当治疗后2天至2周内痊愈。未出现色素沉着异常病例。光热能量（LHE）选择性光热解联合水杨酸似乎是治疗轻至中度银屑病的一种实用方法。患者仅感到轻度不适。无需恢复期。获得的临床结果与脉冲染料激光报道的结果相似；然而，这种新系统似乎更适合作为一种治疗方式被广泛采用。需要进一步随访以确定缓解期是否会与脉冲染料激光治疗报道的一样长。
