Melanonychia - 黑甲病
觀察到不尋常的多行。 黑甲病 (Melanonychia) 大多是良性的，但如果這個級別有許多不規則的線條，則可以考慮進行活檢。
Muehrcke's lines
References
許多患者對黑甲症感到擔憂，因為它會導致指甲板變成棕黑色。這是指甲變色的常見原因，原因從良性到潛在嚴重的，如黑色素瘤。縱向帶狀黑甲症可能源自於各種局部或全身性因素。
Melanonychia is a very worrisome entity for most patients. It is characterized by brownish black discoloration of nail plate and is a common cause of nail plate pigmentation. The aetiology of melanonychia ranges from more common benign causes to less common invasive and in situ melanomas. Melanonychia especially in a longitudinal band form can be due to both local and systemic causes.
Melanonychia is a very worrisome entity for most patients. It is characterized by brownish black discoloration of nail plate and is a common cause of nail plate pigmentation. The aetiology of melanonychia ranges from more common benign causes to less common invasive and in situ melanomas. Melanonychia especially in a longitudinal band form can be due to both local and systemic causes.
Melanonychia represents a brown to black discoloration of the nail plate that may be induced by benign or malignant causes. Two main mechanisms are involved in the appearance of melanonychias, i.e., melanocytic activation and melanocytic hyperplasia.
甲週組織上有一條寬而深的色素帶，具有不規則的線條和色素延伸，是黑色素瘤的徵兆。