Melanocytic nevi of left upper eyelid, including canthus

This code signifies the presence of a melanocytic nevus, commonly known as a mole, located specifically on the left upper eyelid, encompassing the canthal region. These are benign proliferations of melanocytes, appearing as pigmented lesions.

Apply this code when documentation clearly identifies a melanocytic nevus on the patient's left upper eyelid, including any involvement of the inner or outer canthus. This is appropriate for initial diagnosis, follow-up, or prior to excision of such a lesion.

• Ensure the documentation specifies "left" upper eyelid; laterality is crucial for accurate coding.
• Distinguish from malignant melanoma (C43.-) or other benign eyelid lesions (e.g., D23.121 for other benign neoplasms of the left upper eyelid).
• Verify the lesion is indeed a nevus and not another type of pigmented lesion requiring a different code.