Lower energy and pulse stacking. A safer alternative for skin tightening using fractional CO2 laser

PURPOSE : To evaluate the effect of different energies and stacking in skin shrinkage. METHODS : Three decreasing settings of a fractional CO2 laser were applied to the abdomen of Twenty five Wistar rats divided into three groups. Group I (n=5) was histologically evaluated for microthermal zones dimensions. Groups II and III (n=10 each) were macroscopic evaluated with freeware ImageJ for area contraction immediately and after 30 and 60 days. RESULTS : No statistical significance was found within microthermal zone histological dimensions (Group I) in all settings studied. (Ablation depth: 76.90 to 97.18µm; Coagulation depth: 186.01 to 219.84 µm). In Group II, macroscopic evaluation showed that all settings cause significant immediate skin contraction. The highest setting cause significant more intense tightening effect initially, contracting skin area from 258.65 to 179.09 mm2. The same pattern was observed in Group III. At 30 and 60 days, the lowest setting significantly sustained contraction. CONCLUSION : Lower fractional CO2 laser energies associated to pulse stacking could cause consistent and long lasting tissue contraction in rats.

Fractional Erbium laser in the treatment of photoaging: randomized comparative, clinical and histopathological study of ablative (2940nm) vs. non-ablative (1540nm) methods after 3 months

BACKGROUND: Fractional non-ablative lasers keep the epidermis intact, while fractional ablative lasers remove it, making them theoretically more effective. OBJECTIVES: To evaluate the clinical and histological alterations induced by fractional photothermolysis for treating photoaging, comparing the possible equivalence of multiple sessions of 1540nm Erbium, to one session of 2940nm Erbium. METHODS: Eighteen patients (mean age 55.9) completed the treatment with three sessions of 1540nm fractional Erbium laser on one side of the face (50 mJ/mB, 15ms, 2 passes), and one session of 2940nm on the other side (5mJ/mB, 0.25ms, 2 passes). Biopsies were performed before and 3 months after treatment. Clinical, histological and morphometric evaluations were carried out. RESULTS: All patients presented clinical improvement with no statistically significant difference (p> 0.05) between the treated sides. Histopathology revealed a new organization of collagen and elastic fibers, accompanied by edema, which was more evident with the 2940nm laser. This finding was confirmed by morphometry, which showed a decrease in collagen density for both treatments, with a statistical significance for the 2940nm laser (p > 0.001). CONCLUSIONS: Three 1540nm sessions were clinically equivalent to one 2940nm session. The edema probably contributed to the positive results after three months, togheter with the new collagen and elastic fibers organization. The greater edema after the 2940nm session indicates that dermal remodeling takes longer than with 1540nm. It is possible that this histological superiority relates to a more prolonged effect, but a cohort longer than three months is needed to confirm that supposition. .

Evaluación de los efectos del LED en el tejido dérmico de ratones / The effect of application of red LED on the dermis of rats

Diodos Emisores de la Luz- Light Emitting Diodes (LED) son fuentes de luz que están siendo introducidos en los tratamientos del envejecimiento. El objetivo del estudio fue evaluar los efectos del LED rojo en la dermis de ratones wistar. Se trata de un estudio experimental controlado y randomizado, fueron utilizados 20 ratones wistar divididos en cinco grupos. Los grupos fueron: G1 en donde se aplicó 10 sesiones de diez minutos de fototerapia por LED. El G2 con 20 sesiones de 10minutos, el G3 con 10 sesiones de 20 minutos, el G4 con 20 sesiones de 20 minutos y el G5 fue el grupo control. Después de las aplicaciones se recolectó el material biológico de la zona, siendo realizado el análisis histológico de las áreas que recibieron las aplicaciones, sometiéndolas a las coloraciones de HE, tricómico de Masson y Verhoeef. Fue observada la presencia de micro vasos dérmicos con resultados significativos entre el G2 y el G5. Con relación a la presencia de mastocitos hubo resultados significativos entre el G1 y el G3. El análisis de las fibras elásticas presentó resultados significativos en los grupos G1, G2, G3, G4 en comparación al grupo control (G5). La evaluación de los efectos del LED en las fibras colágenos, los grupos tratados comparados al grupo control no presentaron ninguna diferencia significativa.

The Light-Emitting Diodes Light Emitting Diodes (LED) are a source of light wich are being introduced into the treatment of aging process. This study evaluate the effect of application of red LED on the dermis of Wistar rats. Twenty Wistar rats were used in this randomized controlled experimental study. Those rats were divided randomly into five groups. The G1 group underwent ten sessions of phototherapy by LED lasting ten minutes each. The G-2, 20 sessions of 10 minutes, the G-3, 20 minutes, the fourth group, 20 sessions of 20 minutes and the G-5 group was the control group. After the application, the biological material was collected and the histological analysis of the areas that suffered application were done, being subjected to HE staining, and Masson trichrome & Verhoeff. It was observed the presence of dermal microvascular, with significant results among G2 and G5 groups. Regarding the presence of mast cells, significant results were observed among G1 and G3 groups, however, that was not the case with the G5. By analyzing the elastic fibers, significant results were observed among G1, G2, G3, G4 groups, but the same results weren’t observed in the fifth group. Regarding the assessment of the effects of LED on the collagen fibers, the treated groups, when compared to the control group, showed no significant difference.

effects of x-rays on the hair follicles, blood vessels, collagen and elastic fibers, of the skin of guinea pigs and the role of vitamin C, a morphological study under light microscope

To observe the effects of x-rays on hair follicles, blood vessels and collagen and elastic fibers of the skin and role of vitamin C. A prospective experimental study. This study was conducted at the Department of Anatomy, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre Karachi from 2008 to 2009. Twenty seven animals were taken and were divided in to three groups. Each group was further subdivided into three subgroups containing three animals each according to the time of sacrifice i.e. 48 hours, 15[th] day and 45 [th] day respectively. A single whole body x-irradiation in a dose of 5 Gy was given. Group C animals were also given injection of vitamin-C intraperitoneally in the dose of 1mg/G/day. Animals were sacrificed under either anaesthesia after completion of their respective periods. Tissues were processed and 4-5 micron thick paraffin embedded sections were cut and stained with Hematoxylin and eosin for morphology of hair follicles and blood vessels, Masson's trichrome for study of collagen and Van Geison for elastic fibers. Group A served as control. In Group 'B' hair follicles were reduced in size and number of cells per bulb was also reduced, blood vessels were dilated their endothelial cells were swollen lumen was narrow and vessel wall great extent in less than 15 days but there was no sign of improvement in elastic fibers. X-rays have hazardous effects on hair follicles, blood vessels and collagen fiber elastic fiber. Vitamin C minimizes these hazardous effects

Luz intensa pulsada no fotoenvelhecimento: avaliação clínica, histopatológica e imuno-histoquímica / Intense pulsed light in photoaging: a clinical, histopathological and immunohistochemical evaluation

FUNDAMENTOS: A luz intensa pulsada tem sido muito utilizada no tratamento do fotoenvelhecimento sem completo conhecimento de seu mecanismo de ação. OBJETIVO: Estudar a ação da luz intensa pulsada no fotoenvelhecimento e na resposta imunológica cutânea por meio de estudo clínico, histopatológico, avaliando células de Langerhans (CD1), expressão da molécula de adesão intercelular, de linfócitos CD4 e CD8 e quantificação de colágeno e fibras elásticas. MÉTODOS: Um total de 26 pacientes, com idades entre 40 e 65 anos, com fototipos II a III de Fitzpatrick, foram tratadas do fotoenvelhecimento usando LIP, em 5 sessões, com intervalo mensal, durante o ano de 2006. Todas as pacientes foram submetidas à avaliação histológica e imuno-histoquímica 6 meses após o tratamento. RESULTADOS: Ao término do tratamento, houve melhora clínica em 76,92 por cento dos casos, estando relacionada ao aumento significante de fibras colágenas (51,33 por cento) e elásticas (44,13 por cento). O tratamento com luz intensa pulsada promoveu redução de linfócitos CD4 e não alterou a intensidade de linfócitos CD8. Além disso, promoveu aumento significante de pequenos vasos sanguíneos, não ectásicos, molécula de adesão intercelular positivos. CONCLUSÃO: O tratamento facial com luz intensa pulsada promoveu intensa melhora clínica que foi comprovada pelo estudo histopatológico da pele, constituindo boa opção de tratamento para o fotoenvelhecimento cutâneo, por ser técnica não- ablativa, segura e eficaz.

BACKGROUND: Intense pulsed light has been used in the treatment of photoaging without a full understanding of its mechanism of action. OBJECTIVE: To study the effect of intense pulsed light on photoaging and on the skin immune response by means of a clinical and histopathological study, evaluating Langerhans cells (CD1), expression of intercellular adhesion molecule, of CD4 and CD8 lymphocytes and quantification of collagen and elastic fibers. METHODS: In 2006 a total of 26 patients, aged 40 to 65 years, with phototypes II to III (Fitzpatrick scale), were treated for photoaging using intense pulsed light in five sessions with a monthly interval. All the patients were subjected to histological and immunohistochemical evaluation 6 months after treatment. RESULTS: At the end of the treatment clinical improvement was observed in 76.92 percent of cases. This improvement was associated to a significant increase of collagen (51.33 percent) and elastic (44.13 percent) fibers. Intense pulsed light treatment led to a reduction of CD4 lymphocytes and did not alter the amount of CD8 lymphocytes. It also led to a significant increase of small, nonectatic blood vessels, positive intercellular adhesion molecule. CONCLUSION: Facial treatment with intense pulsed light promoted major clinical improvement that was confirmed by histological examination of the skin. This technique is a good treatment option for skin photoaging because it is non-ablative, safe and effective.