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2.
An Acad Bras Cienc ; 92(1): e20190554, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32491128

RESUMO

Skin is the outermost and largest organ of the human body that protects us from the external agents. Among the various types of diseases affecting the skin, melanoma (skin cancer) is the most dangerous and deadliest disease. Though it is one of the dangerous forms of cancer, it has a high survival rate if and only if it is diagnosed at the earliest. In this study, skin cancer classification (SCC) system is developed using dermoscopic images. It is considered as a classification problem with the help of Bendlet Transform (BT) as features and Support Vector Machine (SVM) as a classifier. First, the unwanted information's such as hair and noises are removed using median filtering approach. Then, directional representation based feature extraction system that precisely classifies curvature, location and orientation is employed. Finally, two SVM classifiers are designed for the classification. The performance of the SCC system based on Bendlet is superior to other image representation systems such as Wavelets, Curvelets, Contourlets and Shearlets.


Assuntos
Dermoscopia/métodos , Melanoma/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Máquina de Vetores de Suporte , Diagnóstico por Computador , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
PLoS One ; 15(6): e0234352, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32544197

RESUMO

Asymmetry, color variegation and diameter are considered strong indicators of malignant melanoma. The subjectivity inherent in the first two features and the fact that 10% of melanomas tend to be missed in the early diagnosis due to having a diameter less than 6mm, deem it necessary to develop an objective computer vision system to evaluate these criteria and aid in the early detection of melanoma which could eventually lead to a higher 5-year survival rate. This paper proposes an approach for evaluating the three criteria objectively, whereby we develop a measure to find asymmetry with the aid of a decision tree which we train on the extracted asymmetry measures and then use to predict the asymmetry of new skin lesion images. A range of colors that demonstrate the suspicious colors for the color variegation feature have been derived, and Feret's diameter has been utilized to find the diameter of the skin lesion. The decision tree is 80% accurate in determining the asymmetry of skin lesions, and the number of suspicious colors and diameter values are objectively identified.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Melanoma/diagnóstico por imagem , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico , Algoritmos , Cor , Tomada de Decisões Assistida por Computador , Dermoscopia/métodos , Humanos , Melanoma/patologia , Dermatopatias , Neoplasias Cutâneas/patologia
4.
J Dtsch Dermatol Ges ; 18(7): 692-697, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32597015

RESUMO

BACKGROUND AND OBJECTIVES: The incidence of melanoma is rising and prevention plays an important role. Multiple nevi as well as a medical history of melanoma are important risk factors. In affected patients, a two-step algorithm consisting of total-body photography (TBP) and sequential digital dermatoscopy (SDD) is a helpful diagnostic tool. PATIENTS AND METHODS: This was a retrospective observational study that lasted six years in order to evaluate the significance of the two-step algorithm. Cases were evaluated based on distinct dermoscopic patterns and statistical analyses were performed with the latest version of SPSS. RESULTS: 6020 dermoscopic images of 214 patients were included. TBP was performed at a mean interval of 16.9 months (SD ± 1.43 months), while SDD was performed every 9.9 months (SD ± 1.68 months). The number needed to excise was 4.6 and the number needed to monitor was 548. Excisions were mostly performed because dynamic changes were observed. A total of eleven melanomas were detected and had a mean tumor thickness of 0.44 mm (SD ± 0.15 mm; range 0.2-0.6 mm). CONCLUSIONS: Invasive melanomas had a tumor thickness of less than 0.6 mm, thus providing evidence of an effective strategy for early melanoma detection. Excisions of benign nevi were minimized as indicated by a low number needed to excise.


Assuntos
Algoritmos , Dermoscopia/métodos , Melanoma/diagnóstico , Fotografação , Neoplasias Cutâneas/diagnóstico , Humanos , Melanoma/patologia , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Fatores de Tempo
6.
Hautarzt ; 71(8): 627-646, 2020 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-32377768

RESUMO

Dermatoscopy as a noninvasive diagnostic tool is not only useful in the differentiation of malignant and benign skin tumors, but is also effective in the diagnosis of inflammatory, infiltrative and infectious dermatoses. As a result, the need for diagnostic punch biopsies in dermatoses could be reduced. Hereby the selection of affected skin areas is essential. The diagnostic accuracy is independent of the skin type. Helpful dermatoscopic features include vessels morphology and distribution, scales colors and distribution, follicular findings, further structures such as colors and morphology as well as specific clues. The dermatoscopic diagnosis is made based on the descriptive approach in clinical routine, teaching and research. In all clinical and dermatoscopic diagnoses that remain unclear, a punch biopsy with histopathology should be performed. The dermatoscope should be cleaned after every examination according to the guidelines.


Assuntos
Dermoscopia/métodos , Dermatopatias Infecciosas/diagnóstico , Neoplasias Cutâneas/diagnóstico , Pele/diagnóstico por imagem , Humanos
7.
J Cancer Res Ther ; 16(1): 40-52, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32362608

RESUMO

Context: Skin cancer is a complex and life-threatening disease caused primarily by genetic instability and accumulation of multiple molecular alternations. Aim: Currently, there is a great interest in the prospects of image processing to provide quantitative information about a skin lesion, that can be relevance for the clinical images and also used as a stand-alone cautioning tool. Setting and Design: To accomplish a powerful approach to recognize skin cancer without performing any unnecessary skin biopsies, this article presents a new hybrid technique for the classification of skin images using Firefly with K-Nearest Neighbor algorithm (FKNN). Materials and Methods: FKNN classifier is used to predict and classify skin cancer along with threshold-based segmentation and ABCD feature extraction. Image preprocessing and feature extraction techniques are mandatory for any image-based applications. Statistical Analysis Used: Initially, it is essential to eliminate the illumination variation and the other unwanted shadow areas present in the skin image, which is done by homomorphic filtering called preprocessing. Results: The comparison of our proposed method with other existing methods and a comprehensive discussion is explored based on the obtained results. Conclusion: The proposed FKNN provides a quantitative information about a skin lesion through hybrid KNN and firefly optimization that helps for recognizing the skin cancer efficiently than other technique with low computational complexity and time.


Assuntos
Algoritmos , Dermoscopia/métodos , Lógica Fuzzy , Processamento de Imagem Assistida por Computador/métodos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Análise por Conglomerados , Dermoscopia/instrumentação , Humanos , Melanoma/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Máquina de Vetores de Suporte
8.
Actas dermo-sifiliogr. (Ed. impr.) ; 111(3): 257-260, abr. 2020. ilus
Artigo em Espanhol | IBECS | ID: ibc-191530

RESUMO

El uso de los láseres de colorante pulsado (pulse dye laser [PDL]) y de dióxido de carbono (CO2) para el tratamiento de los dermatofibromas (DF) ha demostrado tener buenos resultados clínicos. Un total de 23 DF fueron tratados en dos sesiones con el láser de alejandrita Q-Switched de 755 nm (7,5 J/cm2, 3 mm, 50 ms), dejando entre cada sesión un intervalo de 4semanas. Para el eritema residual se utilizó el láser V Beam PDL con una longitud de onda de 595nm (10-11 J/cm2, 7 mm, 1,5 ms). En 9 de las pacientes se observó una atenuación parcial de la coloración marrón y en 14 de ellas una desaparición completa de la misma. Las pacientes refirieron un grado elevado de satisfacción después de haber realizado el tratamiento. Así mismo, 15 de las pacientes notaron una disminución en el endurecimiento de los DF. En el examen dermatoscópico previo al tratamiento, en todos los DF se observó la presencia de una red de pigmento. Esta red de pigmento desapareció en todos los casos tras la aplicación del láser. La combinación del láser V Beam PDL y del láser de alejandrita Q-Switched en los DF constituye una alternativa terapéutica adecuada que, además de buenos resultados cosméticos, ha conseguido un elevado grado de satisfacción por parte de los pacientes


Pulsed dye and carbon dioxide lasers have been applied in dermatofibroma with clinical improvement. We treated 23 dermatofibromas two times at a 4-week interval with Q-Switched alexandrite laser 755 nm (7.5 J/cm2, 3 mm, 50 ms). V Beam pulsed dye laser with a wavelength of 595nm was used for the residual erythema (10-11 J/cm2, 7 mm, 1.5 ms). A partial attenuation of brown colour was observed in 9 patients and complete disappearance of brown colour in 14 patients. Patient satisfaction was very high. Fifteen patients felt a decrease in hardening of dermatofibroma after treatment. A pigment network in dermoscopy was observed in all patients before treatment and no one after treatment. A combined treatment using both V Beam pulsed dye laser and Q-Switched alexandrite laser may be a therapeutic option to reduce the aesthetic effect of dermatofibroma with a high patient satisfaction and good cosmetic outcomes


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Histiocitoma Fibroso Benigno/terapia , Lasers de Corante/uso terapêutico , Terapia de Luz Pulsada Intensa , Dermoscopia/métodos , Lasers de Estado Sólido/uso terapêutico , Estudos Prospectivos , Satisfação do Paciente , Hipopigmentação/diagnóstico
11.
An Bras Dermatol ; 95(3): 379-382, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32276794

RESUMO

In situations in when a dermoscopic record of a large lesion is desirable, the resulting images are usually restricted to a small field of view due to the limited diameter of dermatoscope lenses. This limitation often produces several photographs separately, thus losing the possibility of a single-image global evaluation. In these case reports, we show examples of a recently published image montage technique called Wide Area Digital Dermoscopy, in this case, applied to basal cell carcinomas.


Assuntos
Carcinoma Basocelular/diagnóstico por imagem , Dermoscopia/métodos , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Cutâneas/diagnóstico por imagem , Carcinoma Basocelular/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Neoplasias Cutâneas/patologia , Software
12.
An Bras Dermatol ; 95(3): 332-335, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32276798

RESUMO

Tinea capitis comprising of tinea favosa and kerion is mostly seen in school-aged children. Some tinea capitis often presented with insignificant findings under the naked eyes are easily overlooked. The authors describe an unusual case of tinea capitis caused by Trichophyton violaceum. The patient was an 8-year-old girl, with a history of pruritus on the scalp for more than one year. A diagnosis of tinea capitis was confirmed by clinical examination aided by dermoscopy, calcium fluorescent microscopy and culture. Comma and corkscrew hairs are two specific dermoscopic patterns of tinea capitis. The patient was treated with systemic itraconazole, topical application with 1% naftifine 0.25% ketoconazole cream followed after daily hair wash with 2% ketoconazole shampoo for 8 weeks.


Assuntos
Dermoscopia/métodos , Microscopia de Fluorescência/métodos , Tinha do Couro Cabeludo/diagnóstico por imagem , Cálcio , Criança , Feminino , Humanos , Reprodutibilidade dos Testes , Tinha do Couro Cabeludo/patologia , Trichophyton/isolamento & purificação
13.
An Bras Dermatol ; 95(2): 244-246, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32146011

RESUMO

The clinical diagnosis of Kyrle's disease may sometimes be challenging, due to the clinical similarity of lesions to other pruritic dermatosis. Although the dermoscopy is being increasingly used in daily practice, there is insufficient data in literature describing the dermoscopic patterns of Kyrle's disease, since only one report has been published to date. Herein we report our dermoscopic observation with additional diagnostic tips in a case who was diagnosed with Kyrle's disease histopathologically.


Assuntos
Doença de Darier/diagnóstico por imagem , Doença de Darier/patologia , Dermoscopia/métodos , Biópsia , Feminino , Humanos , Queratinócitos/patologia , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
16.
BMJ ; 368: m127, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041693

RESUMO

OBJECTIVE: To examine the validity and findings of studies that examine the accuracy of algorithm based smartphone applications ("apps") to assess risk of skin cancer in suspicious skin lesions. DESIGN: Systematic review of diagnostic accuracy studies. DATA SOURCES: Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, CPCI, Zetoc, Science Citation Index, and online trial registers (from database inception to 10 April 2019). ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Studies of any design that evaluated algorithm based smartphone apps to assess images of skin lesions suspicious for skin cancer. Reference standards included histological diagnosis or follow-up, and expert recommendation for further investigation or intervention. Two authors independently extracted data and assessed validity using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2 tool). Estimates of sensitivity and specificity were reported for each app. RESULTS: Nine studies that evaluated six different identifiable smartphone apps were included. Six verified results by using histology or follow-up (n=725 lesions), and three verified results by using expert recommendations (n=407 lesions). Studies were small and of poor methodological quality, with selective recruitment, high rates of unevaluable images, and differential verification. Lesion selection and image acquisition were performed by clinicians rather than smartphone users. Two CE (Conformit Europenne) marked apps are available for download. SkinScan was evaluated in a single study (n=15, five melanomas) with 0% sensitivity and 100% specificity for the detection of melanoma. SkinVision was evaluated in two studies (n=252, 61 malignant or premalignant lesions) and achieved a sensitivity of 80% (95% confidence interval 63% to 92%) and a specificity of 78% (67% to 87%) for the detection of malignant or premalignant lesions. Accuracy of the SkinVision app verified against expert recommendations was poor (three studies). CONCLUSIONS: Current algorithm based smartphone apps cannot be relied on to detect all cases of melanoma or other skin cancers. Test performance is likely to be poorer than reported here when used in clinically relevant populations and by the intended users of the apps. The current regulatory process for awarding the CE marking for algorithm based apps does not provide adequate protection to the public. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42016033595.


Assuntos
Dermoscopia/métodos , Melanoma/diagnóstico , Aplicativos Móveis , Neoplasias Cutâneas/diagnóstico , Smartphone , Algoritmos , Biópsia , Dermoscopia/instrumentação , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Melanoma/patologia , Reprodutibilidade dos Testes , Medição de Risco/métodos , Pele/diagnóstico por imagem , Pele/patologia , Neoplasias Cutâneas/patologia
18.
An Bras Dermatol ; 95(1): 78-81, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31889590

RESUMO

The number of individuals with tattoos has been increasing worldwide, alongside with reports of complications varying from reactions to the injected pigments to infections caused by agents inoculated in the pigmentation process. The diagnosis of such unwanted events can be obtained through complementary non-invasive methods, preserving the maximum of the tattoo design. The authors present two cases of patients with warts on tattooing, and correlate their clinical aspects to in vivo and ex vivo dermoscopy, and to the findings in the histopathological examination, aiming to determine patterns that aid the diagnosis of these lesions without performing biopsy.


Assuntos
Infecções por Papillomavirus/diagnóstico por imagem , Infecções por Papillomavirus/patologia , Tatuagem/efeitos adversos , Verrugas/diagnóstico por imagem , Verrugas/patologia , Adulto , Biópsia , Corantes/efeitos adversos , Dermoscopia/métodos , Epiderme/patologia , Epiderme/virologia , Humanos , Masculino , Infecções por Papillomavirus/virologia , Verrugas/virologia
19.
An Bras Dermatol ; 95(1): 95-97, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31932162

RESUMO

The Borst-Jadassohn phenomenon is a morphological finding that consists of the presence of well-defined nests of cells located in the spiny stratum of an acanthotic epidermis. One of the neoplasms where this phenomenon is found is hidroacanthoma simplex. This neoplasm is considered the intraepidermal form of the eccrine poroma. Despite its benign nature, malignant transformations are reported. The present article reports a case of hidroacanthoma simplex and discusses the dermoscopy of this phenomenon.


Assuntos
Acantoma/diagnóstico por imagem , Acantoma/patologia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Idoso de 80 Anos ou mais , Biópsia , Dermoscopia/métodos , Epiderme/diagnóstico por imagem , Epiderme/patologia , Feminino , Humanos
20.
Microsc Res Tech ; 83(4): 410-423, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31898863

RESUMO

The numbers of diagnosed patients by melanoma are drastic and contribute more deaths annually among young peoples. An approximately 192,310 new cases of skin cancer are diagnosed in 2019, which shows the importance of automated systems for the diagnosis process. Accordingly, this article presents an automated method for skin lesions detection and recognition using pixel-based seed segmented images fusion and multilevel features reduction. The proposed method involves four key steps: (a) mean-based function is implemented and fed input to top-hat and bottom-hat filters which later fused for contrast stretching, (b) seed region growing and graph-cut method-based lesion segmentation and fused both segmented lesions through pixel-based fusion, (c) multilevel features such as histogram oriented gradient (HOG), speeded up robust features (SURF), and color are extracted and simple concatenation is performed, and (d) finally variance precise entropy-based features reduction and classification through SVM via cubic kernel function. Two different experiments are performed for the evaluation of this method. The segmentation performance is evaluated on PH2, ISBI2016, and ISIC2017 with an accuracy of 95.86, 94.79, and 94.92%, respectively. The classification performance is evaluated on PH2 and ISBI2016 dataset with an accuracy of 98.20 and 95.42%, respectively. The results of the proposed automated systems are outstanding as compared to the current techniques reported in state of art, which demonstrate the validity of the proposed method.


Assuntos
Dermoscopia/métodos , Processamento de Imagem Assistida por Computador/métodos , Melanoma/diagnóstico , Algoritmos , Diagnóstico por Computador , Humanos , Melanoma/classificação , Melanoma/patologia , Redes Neurais de Computação , Pele/patologia
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