Effects of the lower energy and pulse stacking in carbon dioxide laser skin treatment: an objective analysis using second harmonic generation.

PURPOSE: To evaluate the effect of fractional carbon dioxide (CO2) laser treatment using lower power associated with pulse stacking within collagen fibers, using second harmonic generation microscopy and computerized image analysis. METHODS: Twenty male Wistar rats aging eight weeks were used. Each treatment area received a single-pass CO2 fractional laser with different parameters. The 20 animals were divided into two groups and euthanized after 30 and 60 days. Second harmonic generation images were obtained and program ImageJ was utilized to evaluate the collagen organization within all areas. Collagen anisotropy, entropy and optical density were quantified. RESULTS: Increased anisotropy over time was observed in all four areas, but only reached statistical significance (p = 0.0305) when the mildest parameters were used (area four). Entropy decreased over time in all areas, but without significance(p = 0.1779) in area four. Density showed an overtime increase only in area four, but no statistical significance was reached (p = 0.6534). CONCLUSIONS: When combined, the results obtained in this study regarding anisotropy, entropy and density tend to demonstrate that it is possible to achieve collagen remodeling with the use of lower power levels associated with stacked pulses.

Effects of the lower energy and pulse stacking in carbon dioxide laser skin treatment: an objective analysis using second harmonic generation

ABSTRACT Purpose To evaluate the effect of fractional carbon dioxide (CO2) laser treatment using lower power associated with pulse stacking within collagen fibers, using second harmonic generation microscopy and computerized image analysis. Methods Twenty male Wistar rats aging eight weeks were used. Each treatment area received a single-pass CO2 fractional laser with different parameters. The 20 animals were divided into two groups and euthanized after 30 and 60 days. Second harmonic generation images were obtained and program ImageJ was utilized to evaluate the collagen organization within all areas. Collagen anisotropy, entropy and optical density were quantified. Results Increased anisotropy over time was observed in all four areas, but only reached statistical significance (p = 0.0305) when the mildest parameters were used (area four). Entropy decreased over time in all areas, but without significance(p = 0.1779) in area four. Density showed an overtime increase only in area four, but no statistical significance was reached (p = 0.6534). Conclusions When combined, the results obtained in this study regarding anisotropy, entropy and density tend to demonstrate that it is possible to achieve collagen remodeling with the use of lower power levels associated with stacked pulses.

Effects of the lower energy and pulse stacking in carbon dioxide laser skin treatment: an objective analysis using second harmonic generation

ABSTRACT Purpose To evaluate the effect of fractional carbon dioxide (CO2) laser treatment using lower power associated with pulse stacking within collagen fibers, using second harmonic generation microscopy and computerized image analysis. Methods Twenty male Wistar rats aging eight weeks were used. Each treatment area received a single-pass CO2 fractional laser with different parameters. The 20 animals were divided into two groups and euthanized after 30 and 60 days. Second harmonic generation images were obtained and program ImageJ was utilized to evaluate the collagen organization within all areas. Collagen anisotropy, entropy and optical density were quantified. Results Increased anisotropy over time was observed in all four areas, but only reached statistical significance (p = 0.0305) when the mildest parameters were used (area four). Entropy decreased over time in all areas, but without significance(p = 0.1779) in area four. Density showed an overtime increase only in area four, but no statistical significance was reached (p = 0.6534). Conclusions When combined, the results obtained in this study regarding anisotropy, entropy and density tend to demonstrate that it is possible to achieve collagen remodeling with the use of lower power levels associated with stacked pulses.

Second-harmonic generation imaging analysis can help distinguish sarcoidosis from tuberculoid leprosy.

Sarcoidosis and tuberculoid leprosy (TL) are prototypes of granulomatous inflammation in dermatology, which embody one of the histopathology limitations in distinguishing some diseases. Recent advances in the use of nonlinear optical microscopy in skin have enabled techniques, such as second-harmonic generation (SHG), to become powerful tools to study the physical and biochemical properties of skin. We use SHG images to analyze the collagen network, to distinguish differences between sarcoidosis and TL granulomas. SHG images obtained from skin biopsies of 33 patients with TL and 24 with sarcoidosis retrospectively were analyzed using first-order statistics (FOS) and second-order statistics, such as gray-level co-occurrence matrix (GLCM). Among the four parameters evaluated (optical density, entropy, contrast, and second angular moment), only contrast demonstrated statistical significance, being higher in sarcoidosis (p = 0.02; 4908.31 versus 2822.17). The results may indicate insufficient differentiating power for most tested FOS and GLCM parameters in classifying sarcoidosis and TL granulomas, when used individually. But in combination with histopathology (H&E and complementary stains, such as silver and fast acid stains), SHG analysis, like contrast, can contribute to distinguishing between these diseases. This study can provide a way to evaluate collagen distribution in granulomatous diseases.

Histomorphometric approach to differentiate skin lesions of tuberculoid leprosy from sarcoidosis.

BACKGROUND: More than 200 000 new cases of leprosy are detected worldwide annually. Physicians commonly have difficulty in differentiating tuberculoid form of leprosy (TL) from sarcoidosis' cutaneous manifestation. METHODS: Skin biopsies of 33 patients with TL and 24 with sarcoidosis were reviewed on hematoxylin and eosin- and Gomori-stained sections, in order to find reliable criteria for distinguishing one disease from another. RESULTS: Nine of the 24 features analyzed presented significant predictive value for diagnosis (P < .05). Predominance of tuberculoid granulomas in adnexal and neural distribution, and granulomas replacing the nerves localized within sweat gland glomeruli were predictive to TL diagnosis. For sarcoidosis, dermal fibrosis, back-to-back distribution of the granulomas, presence of atypical giant cells and plasma cells, greater number of conventional giant cells, and spared nerves beside the granuloma were predictive criteria. The median surface density of reticulin fibers was significantly higher in sarcoidosis (3.44) than in TL (2.99). Nonetheless, using logistic regression, this variable did not discriminate between the diseases (P = .096). CONCLUSIONS: Isolated histological features are not fully predictive to differentiate the 2 diseases. However, those with statistical value can assist this distinction in diagnostic practice. Although the results of the analysis of the reticulin fibers density did not tell apart TL from sarcoidosis, they corroborate the idea of fiber fragmentation within tuberculoid leprosy granulomas, reiterating the importance of morphometry in the histological examination.

Efeitos do tratamento tópico com ácido hialurônico 0, 2% em queimadura de segundo grau: um relato de experiência / Effects of topical treatment with hyaluronic acid 0, 2% in second-degree burn: an experience report / Efectos del tratamiento tópico con ácido hialurónico 0, 2% quemadura de segundo grado: un relato de experiencia

OBJETIVO: Testar o uso tópico diário e prolongado na cicatrização de queimaduras em idoso, observando-se os parâmetros: tempo de cicatrização, presença ou ausência de cicatrizes hipertróficas e o efeito estético final resultante do tratamento. RELATO DE CASO: Trata-se de um relato de caso realizado em clínicaescola de uma Faculdade de Enfermagem do interior paulista. O estudo descreve o tratamento empregado em lesão por queimadura de segundo grau em uma paciente de 64 anos, que sofreu queimadura de espessura parcial por escaldadura. Foi realizado registro fotográfico e a avaliação da ferida. Inicialmente, a paciente recebeu o tratamento convencional com sulfadiazina de prata 1% durante sete dias. Como não houve resolução, iniciou-se o tratamento com ácido hialurônico (AH) 0,2% diariamente. Com 14 dias de tratamento, observou-se completa reepitelização. Após 27 dias do início do tratamento, a cicatriz apresentou-se com melhora de hiperpigmentação e não havia sinais de hipertrofia. Não foram observados eventos adversos locais ou sistêmicos durante o período de estudo da lesão. CONCLUSÃO: Os dados permitem concluir que a aplicação tópica de AH 0,2% em queimaduras de paciente idoso contribuiu para acelerar a cicatrização, melhorou a evolução do tratamento e o resultado estético.

OBJECTIVE: To test daily and prolonged topical use in the healing of burns in the elderly, considering the parameters: time of healing, presence or absence of hypertrophic scars and the final aesthetic effect resulting from the treatment. CASE REPORT: This is a case report carried out in the clinical school of a School of Nursing at São Paulo state. The study describes the treatment used in second-degree burn injury in a 64-year-old patient who suffered partial thickness burn by scald. Photographic recording and wound evaluation were performed. Initially, the patient received conventional treatment with 1% silver sulfadiazine for seven days. As there was no resolution, treatment with 0.2% hyaluronic acid (HA) was started daily. At 14 days of treatment, complete re-epithelization was observed. After 27 days, the scar presented with improvement of hyperpigmentation and there were no signs of hypertrophy. No local or systemic adverse events were observed during the study period of the lesion. CONCLUSION: The data allow us to conclude that the topical application of AH 0.2% in burns of elderly patients contributed to accelerate healing, improved treatment evolution and aesthetic result.