tailieunhanh - Advanced Techniques in Dermatologic Surgery - part 7

mô học kiểm tra ngay lập tức sau khi (A) tám đi với Er: YAG laser một mình ở 1,7 J với một vị trí 4 đường kính mm và trên 10 đến 20% chồng lên nhau. (B) Ngay sau khi ba đi với Derma-KTM giống hệt Er: YAG thiết lập, nhưng với việc bổ sung của laser CO2 ở mức 10 W và 50 msec thời gian xung | 232 Goldman Figure 12 Histologic examination immediately after A eight passes with the Er YAG laser alone at J with a 4 mm diameter spot and 10 to 20 overlap. B Immediately after three passes with the Derma-KTM at identical Er YAG settings but with the addition of the CO2 laser at 10W and 50 msec pulse duration. C Immediately after four passes with the Derma-KTM at identical Er YAG settings but with the addition of the CO2 laser at 5W and 50 msec pulse duration hematoxylin-eosin 200x . Note minimal amount of nonspecific thermal damage at these laser fluences. Abbreviation Er YAG erbium YAG. Source From Ref. 3. to be used by combining short- and long-pulse passes to ablate and provide thermal effects relatively independently. Adrian and Colleagues reported a side-by-side comparison with the UPCO2 laser on periorbital and perioral areas. They compared the UPCO2 laser set at a density of 5 X 3 passes with 10 10-msec pulses of the Er YAG at 5 J cm2 with a 5-mm diameter spot size on the other side. Postoperative discomfort erythema and time for re-epithelialization were similar. Patients treated with the UPCO2 laser had a better response on deeper wrinkles 13 . Sciton Contour LR This Er YAG laser combines two separate laser heads to combine independent thermal and ablative effects by having one laser head operate LR with the UPCO2 Er YAG Lasers 233 in a short pulse msec with the other head operating in a long pulse mode 1-10 msec . In this manner the Sciton Contour laser ablates tissue with a sequential thermal seal. This laser provides 45 W of power with a 50-Hz repetition rate. At 50 overlap of 3-mm diameter spots fluences of up to 100 J cm2 can be generated. The ablative mode has a short 200 psec suprathreshold pulse. A coagulative pulse immediately follows the ablative pulse. The Sciton ContourTM pattern generator gives a 4-mm spot diameter with a scanning field variable to cm X cm. Spots can be overlapped from 10 to 50 . The pattern has an .