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Nathaniel J. Jellinek - One of the best experts on this subject based on the ideXlab platform.
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Longitudinal Melanonychia: detection and management of nail melanoma.
Hand surgery : an international journal devoted to hand and upper limb surgery and related research : journal of the Asia-Pacific Federation of Societ, 2013Co-Authors: Kathleen A. Mannava, Leslie Robinson-bostom, Sandeep Mannava, L. Andrew Koman, Nathaniel J. JellinekAbstract:Malignant melanoma of the nail confers a higher mortality rate compared to other cutaneous melanomas, which is often attributable to delayed diagnosis. Two-thirds of nail melanomas present as longitudinal Melanonychia (LM), longitudinally-oriented brown-black bands of pigment in the nail plate. This article delineates the appropriate clinical approach toward evaluation and management of a patient with longitudinal Melanonychia, which includes determining risk factors for melanoma, recognizing scenarios in which biopsy is indicated, selecting the appropriate biopsy technique, and managing a patient in whom the diagnosis of nail melanoma has been made.
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REVIEW ARTICLE LONGITUDINAL Melanonychia: DETECTION AND MANAGEMENT OF NAIL MELANOMA
2013Co-Authors: Kathleen A. Mannava, Leslie Robinson-bostom, Sandeep Mannava, L. Andrew Koman, Nathaniel J. JellinekAbstract:Malignant melanoma of the nail confers a higher mortality rate compared to other cutaneous melanomas, which is often attributable to delayed diagnosis. Two-thirds of nail melanomas present as longitudinal Melanonychia (LM), longitudinallyoriented brown-black bands of pigment in the nail plate. This article delineates the appropriate clinical approach toward evaluation and management of a patient with longitudinal Melanonychia, which includes determining risk factors for melanoma, recognizing scenarios in which biopsy is indicated, selecting the appropriate biopsy technique, and managing a patient in whom the diagnosis of nail melanoma has been made.
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midline paramedian longitudinal matrix excision with flap reconstruction alternative surgical techniques for evaluation of longitudinal Melanonychia
Journal of The American Academy of Dermatology, 2010Co-Authors: Siobhan C. Collins, Katharine B. Cordova, Nathaniel J. JellinekAbstract:Background Surgical evaluation of longitudinal Melanonychia requires biopsy of the nail matrix. Previous publications have presented detailed surgical approaches to this problem. However, discussion of longitudinal excision with local matrix flap reconstruction is documented sparsely in the literature. Objective To describe the indications for and technique of performing a longitudinal, full-thickness excision for longitudinal Melanonychia; as this surgery poses a high risk of postoperative split nail, reconstruction is essential. Three local matrix flaps are detailed to maximize functional and cosmetic results. Methods The authors detail the different procedures, with several illustrations and clinical photographs highlighting the techniques. Results These techniques provide the surgeon with additional approaches to excise lesions of longitudinal Melanonychia and reconstruct the surgical defects. Limitations All surgeries of the nail matrix pose a risk of postoperative nail dystrophy and/or split nail. Conclusion The different flaps provide elegant local alternatives to second-intention healing and maximize cosmetic and functional results after matrix excision with narrow margins for longitudinal Melanonychia.
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Midline/paramedian longitudinal matrix excision with flap reconstruction: alternative surgical techniques for evaluation of longitudinal Melanonychia.
Journal of the American Academy of Dermatology, 2010Co-Authors: Siobhan C. Collins, Katharine B. Cordova, Nathaniel J. JellinekAbstract:Background Surgical evaluation of longitudinal Melanonychia requires biopsy of the nail matrix. Previous publications have presented detailed surgical approaches to this problem. However, discussion of longitudinal excision with local matrix flap reconstruction is documented sparsely in the literature. Objective To describe the indications for and technique of performing a longitudinal, full-thickness excision for longitudinal Melanonychia; as this surgery poses a high risk of postoperative split nail, reconstruction is essential. Three local matrix flaps are detailed to maximize functional and cosmetic results. Methods The authors detail the different procedures, with several illustrations and clinical photographs highlighting the techniques. Results These techniques provide the surgeon with additional approaches to excise lesions of longitudinal Melanonychia and reconstruct the surgical defects. Limitations All surgeries of the nail matrix pose a risk of postoperative nail dystrophy and/or split nail. Conclusion The different flaps provide elegant local alternatives to second-intention healing and maximize cosmetic and functional results after matrix excision with narrow margins for longitudinal Melanonychia.
Josette André - One of the best experts on this subject based on the ideXlab platform.
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tangential excision of pigmented nail matrix lesions responsible for longitudinal Melanonychia evaluation of the technique on a series of 30 patients
Journal of The American Academy of Dermatology, 2013Co-Authors: Bertrand Richert, Anne Theunis, Sarah Norrenberg, Josette AndréAbstract:Objectives We sought to assess the shave biopsy technique, which is a new surgical procedure for complete removal of longitudinal Melanonychia. We evaluated the quality of the specimen submitted for pathological examination, assessed the postoperative outcome, and ascertained its indication between the other types of matrix biopsies. Design This was a retrospective study performed at the dermatologic departments of the Universities of Liege and Brussels, Belgium, of 30 patients with longitudinal or total Melanonychia. Results Pathological diagnosis was made in all cases; 23 patients were followed up during a period of 6 to 40 months. Seventeen patients had no postoperative nail plate dystrophy (74%) but 16 patients had recurrence of pigmentation (70%). Limitations This was a retrospective study. Conclusions Shave biopsy is an effective technique for dealing with nail matrix lesions that cause longitudinal Melanonychia over 4 mm wide. Recurrence of pigmentation is the main drawback of the procedure.
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Consensus on Melanonychia nail plate dermoscopy
Anais brasileiros de dermatologia, 2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical professionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.
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consenso sobre dermatoscopia da placa ungueal em melanoniquias consensus on Melanonychia nail plate dermoscopy
2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:Resumo: Este consenso, com foco em melanoniquia e dermatoscopia da lâmina ungueal, se destina a orientar os medicos que trabalham com melanoniquia e auxiliar no manejo destes pacientes. O grupo internacional de estu- dos sobre melanoniquia foi fundada em 2007 e tem agora 30 membros, incluindo dermatologistas e dermatopa- tologistas com conhecimento especializado em unhas. A necessidade de definicoes comuns de dermatoscopia da lâmina ungueal foi abordada durante a segunda reuniao deste grupo, realizada em fevereiro de 2008. Antes desta reuniao e ate a presente, nao existem orientacoes com base em evidencias sobre a utilizacao de dermatoscopia da placa ungueal. Palavras-chave: Dermoscopia; Doencas da unha; Melanoma; Unhas Abstract: This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical pro- fessionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.
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Consensus on Melanonychia nail plate dermoscopy Consenso sobre dermatoscopia da placa ungueal em melanoniquias
Sociedade Brasileira de Dermatologia, 2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical professionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.Este consenso, com foco em melanoníquia e dermatoscopia da lâmina ungueal, se destina a orientar os médicos que trabalham com melanoníquia e auxiliar no manejo destes pacientes. O grupo internacional de estudos sobre melanoníquia foi fundada em 2007 e tem agora 30 membros, incluindo dermatologistas e dermatopatologistas com conhecimento especializado em unhas. A necessidade de definições comuns de dermatoscopia da lâmina ungueal foi abordada durante a segunda reunião deste grupo, realizada em fevereiro de 2008. Antes desta reunião e até a presente, não existem orientações com base em evidências sobre a utilização de dermatoscopia da placa ungueal
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Longitudinal Melanonychia in children: a clinical and histopathologic study of 40 cases.
Journal of the American Academy of Dermatology, 1999Co-Authors: Sophie Goettmann-bonvallot, Josette André, Stéphane BelaichAbstract:Abstract Objective: Very little has been published on longitudinal Melanonychia in children. Our objective was to determine the nature of melanocytic lesions in pediatric patients with longitudinal or total Melanonychia and to look for correlations between clinical and histologic features. Methods: All patients younger than 16 years of age with longitudinal or total Melanonychia who were evaluated at our nail disorder outpatient clinic between September 1993 and September 1996 were included. The clinical and histologic features of the nail condition were determined in each case. Results: Forty patients were included. The final diagnosis was nevus in 19 cases (junctional in 17 cases and compound in 2), lentigo in 12 cases, and functional longitudinal Melanonychia in 9. The latter corresponded to a hyperpigmentation caused by melanocytic activation with no increase in the number of melanocytes. None of the patients had melanoma. Appearance within the first year of life, periungual pigmentation, and total Melanonychia were consistent features in patients with melanocytic hyperplasia (lentigo or nevus). Early onset of a dark broad lesion in a white patient was typical of melanocytic hyperplasia, although none of these features were pathognomonic. Conclusion: Benign melanocytic hyperplasia (lentigo or nevus) was the cause of 77.5% of cases of longitudinal Melanonychia in our overall pediatric population and of 85% of cases in the subset of white patients. All the remaining cases of longitudinal Melanonychia were the result of melanocytic activation. (J Am Acad Dermatol 1999;41:17-22.)
Siobhan C. Collins - One of the best experts on this subject based on the ideXlab platform.
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midline paramedian longitudinal matrix excision with flap reconstruction alternative surgical techniques for evaluation of longitudinal Melanonychia
Journal of The American Academy of Dermatology, 2010Co-Authors: Siobhan C. Collins, Katharine B. Cordova, Nathaniel J. JellinekAbstract:Background Surgical evaluation of longitudinal Melanonychia requires biopsy of the nail matrix. Previous publications have presented detailed surgical approaches to this problem. However, discussion of longitudinal excision with local matrix flap reconstruction is documented sparsely in the literature. Objective To describe the indications for and technique of performing a longitudinal, full-thickness excision for longitudinal Melanonychia; as this surgery poses a high risk of postoperative split nail, reconstruction is essential. Three local matrix flaps are detailed to maximize functional and cosmetic results. Methods The authors detail the different procedures, with several illustrations and clinical photographs highlighting the techniques. Results These techniques provide the surgeon with additional approaches to excise lesions of longitudinal Melanonychia and reconstruct the surgical defects. Limitations All surgeries of the nail matrix pose a risk of postoperative nail dystrophy and/or split nail. Conclusion The different flaps provide elegant local alternatives to second-intention healing and maximize cosmetic and functional results after matrix excision with narrow margins for longitudinal Melanonychia.
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Midline/paramedian longitudinal matrix excision with flap reconstruction: alternative surgical techniques for evaluation of longitudinal Melanonychia.
Journal of the American Academy of Dermatology, 2010Co-Authors: Siobhan C. Collins, Katharine B. Cordova, Nathaniel J. JellinekAbstract:Background Surgical evaluation of longitudinal Melanonychia requires biopsy of the nail matrix. Previous publications have presented detailed surgical approaches to this problem. However, discussion of longitudinal excision with local matrix flap reconstruction is documented sparsely in the literature. Objective To describe the indications for and technique of performing a longitudinal, full-thickness excision for longitudinal Melanonychia; as this surgery poses a high risk of postoperative split nail, reconstruction is essential. Three local matrix flaps are detailed to maximize functional and cosmetic results. Methods The authors detail the different procedures, with several illustrations and clinical photographs highlighting the techniques. Results These techniques provide the surgeon with additional approaches to excise lesions of longitudinal Melanonychia and reconstruct the surgical defects. Limitations All surgeries of the nail matrix pose a risk of postoperative nail dystrophy and/or split nail. Conclusion The different flaps provide elegant local alternatives to second-intention healing and maximize cosmetic and functional results after matrix excision with narrow margins for longitudinal Melanonychia.
Bertrand Richert - One of the best experts on this subject based on the ideXlab platform.
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tangential excision of pigmented nail matrix lesions responsible for longitudinal Melanonychia evaluation of the technique on a series of 30 patients
Journal of The American Academy of Dermatology, 2013Co-Authors: Bertrand Richert, Anne Theunis, Sarah Norrenberg, Josette AndréAbstract:Objectives We sought to assess the shave biopsy technique, which is a new surgical procedure for complete removal of longitudinal Melanonychia. We evaluated the quality of the specimen submitted for pathological examination, assessed the postoperative outcome, and ascertained its indication between the other types of matrix biopsies. Design This was a retrospective study performed at the dermatologic departments of the Universities of Liege and Brussels, Belgium, of 30 patients with longitudinal or total Melanonychia. Results Pathological diagnosis was made in all cases; 23 patients were followed up during a period of 6 to 40 months. Seventeen patients had no postoperative nail plate dystrophy (74%) but 16 patients had recurrence of pigmentation (70%). Limitations This was a retrospective study. Conclusions Shave biopsy is an effective technique for dealing with nail matrix lesions that cause longitudinal Melanonychia over 4 mm wide. Recurrence of pigmentation is the main drawback of the procedure.
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Consensus on Melanonychia nail plate dermoscopy
Anais brasileiros de dermatologia, 2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical professionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.
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consenso sobre dermatoscopia da placa ungueal em melanoniquias consensus on Melanonychia nail plate dermoscopy
2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:Resumo: Este consenso, com foco em melanoniquia e dermatoscopia da lâmina ungueal, se destina a orientar os medicos que trabalham com melanoniquia e auxiliar no manejo destes pacientes. O grupo internacional de estu- dos sobre melanoniquia foi fundada em 2007 e tem agora 30 membros, incluindo dermatologistas e dermatopa- tologistas com conhecimento especializado em unhas. A necessidade de definicoes comuns de dermatoscopia da lâmina ungueal foi abordada durante a segunda reuniao deste grupo, realizada em fevereiro de 2008. Antes desta reuniao e ate a presente, nao existem orientacoes com base em evidencias sobre a utilizacao de dermatoscopia da placa ungueal. Palavras-chave: Dermoscopia; Doencas da unha; Melanoma; Unhas Abstract: This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical pro- fessionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.
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Consensus on Melanonychia nail plate dermoscopy Consenso sobre dermatoscopia da placa ungueal em melanoniquias
Sociedade Brasileira de Dermatologia, 2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical professionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.Este consenso, com foco em melanoníquia e dermatoscopia da lâmina ungueal, se destina a orientar os médicos que trabalham com melanoníquia e auxiliar no manejo destes pacientes. O grupo internacional de estudos sobre melanoníquia foi fundada em 2007 e tem agora 30 membros, incluindo dermatologistas e dermatopatologistas com conhecimento especializado em unhas. A necessidade de definições comuns de dermatoscopia da lâmina ungueal foi abordada durante a segunda reunião deste grupo, realizada em fevereiro de 2008. Antes desta reunião e até a presente, não existem orientações com base em evidências sobre a utilização de dermatoscopia da placa ungueal
Pier Alessandro Fanti - One of the best experts on this subject based on the ideXlab platform.
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Tips for Diagnosis and Treatment of Nail Pigmentation with Practical Algorithm
Dermatologic Clinics, 2015Co-Authors: Bianca Maria Piraccini, Emi Dika, Pier Alessandro FantiAbstract:The observation of a black-brown pigmentation of the nail is often alarming for the patient and for the clinician, as they are aware that it can be a possible clinical manifestation of melanoma of the nail apparatus. Luckily, however, nail melanoma is a much less frequent cause of brown-black nail color than other melanocytic and nonmelanocytic pigmentations, which include subungual hematoma, exogenous pigmentations, and Melanonychia due to benign conditions. A correct clinical history and careful examination help the clinician to distinguish the different conditions and to decide the correct management of Melanonychia both in children and in adults.
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Consensus on Melanonychia nail plate dermoscopy
Anais brasileiros de dermatologia, 2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical professionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.
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consenso sobre dermatoscopia da placa ungueal em melanoniquias consensus on Melanonychia nail plate dermoscopy
2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:Resumo: Este consenso, com foco em melanoniquia e dermatoscopia da lâmina ungueal, se destina a orientar os medicos que trabalham com melanoniquia e auxiliar no manejo destes pacientes. O grupo internacional de estu- dos sobre melanoniquia foi fundada em 2007 e tem agora 30 membros, incluindo dermatologistas e dermatopa- tologistas com conhecimento especializado em unhas. A necessidade de definicoes comuns de dermatoscopia da lâmina ungueal foi abordada durante a segunda reuniao deste grupo, realizada em fevereiro de 2008. Antes desta reuniao e ate a presente, nao existem orientacoes com base em evidencias sobre a utilizacao de dermatoscopia da placa ungueal. Palavras-chave: Dermoscopia; Doencas da unha; Melanoma; Unhas Abstract: This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical pro- fessionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.
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Consensus on Melanonychia nail plate dermoscopy Consenso sobre dermatoscopia da placa ungueal em melanoniquias
Sociedade Brasileira de Dermatologia, 2013Co-Authors: Nilton Di Chiacchio, Pier Alessandro Fanti, Bianca Maria Piraccini, Débora Cadore De Farias, Sergio Henrique Hirata, Bertrand Richert, Martin Zaiac, R. Daniel, Josette André, Beth S. RubenAbstract:This statement, focused on Melanonychia and nail plate dermoscopy, is intended to guide medical professionals working with Melanonychia and to assist choosing appropriate management for Melanonychia patients. The International Study Group on Melanonychia was founded in 2007 and currently has 30 members, including nail experts and dermatopathologists with special expertise in nails. The need for common definitions of nail plate dermoscopy was addressed during the Second Meeting of this Group held in February 2008. Prior to this meeting and to date (2010) there have been no evidence-based guidelines on the use of dermoscopy in the management of nail pigmentation.Este consenso, com foco em melanoníquia e dermatoscopia da lâmina ungueal, se destina a orientar os médicos que trabalham com melanoníquia e auxiliar no manejo destes pacientes. O grupo internacional de estudos sobre melanoníquia foi fundada em 2007 e tem agora 30 membros, incluindo dermatologistas e dermatopatologistas com conhecimento especializado em unhas. A necessidade de definições comuns de dermatoscopia da lâmina ungueal foi abordada durante a segunda reunião deste grupo, realizada em fevereiro de 2008. Antes desta reunião e até a presente, não existem orientações com base em evidências sobre a utilização de dermatoscopia da placa ungueal
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Nail matrix nevi: A clinical and histopathologic study of twenty-two patients
Journal of the American Academy of Dermatology, 1996Co-Authors: Antonella Tosti, Bianca Maria Piraccini, Robert Baran, Norma Cameli, Pier Alessandro FantiAbstract:Abstract Background: Because most dermatologists do not regularly perform biopsies of longitudinal Melanonychia, even when the pigmentation presents as a single band, the true prevalence of nail matrix nevi is unknown. Objective: Our purpose was to determine the prevalence of nail matrix nevi in white patients with longitudinal Melanonychia involving a single digit and to determine whether longitudinal Melanonychia caused by a nail matrix nevus can be clinically distinguished from longitudinal Melanonychia from other causes. Methods: From January 1989 to December 1994 we performed a nail biopsy on 100 of 128 consecutive white patients who had a single band of “idiopathic” longitudinal Melanonychia. Results: A nail matrix nevus was detected in 22 patients. A junctional nevus was found in 19 specimens and a compound nevus in three specimens. Conclusion: Nail matrix nevi in Caucasian patients are uncommon but not exceptional. The number of nevi presenting with longitudinal Melanonychia exceeded that of melanoma. The diagnosis of nail matrix nevi is impossible clinically and always requires histopathologic study. The pathologic features of nail matrix nevi are similar to those of skin nevi except for their architectural pattern, which reflects the peculiar anatomy of the nail unit.