Medial Canthal Haemangioma Section Mimicking a Dermoid Cyst: A Diagnostic Challenge

Haemangiomas are benign vascular neoplasms typically diagnosed in infants and rarely seen in adults. Their occurrence in the medial canthal region is particularly uncommon and may clinically mimic more frequent benign lesions such as dermoid cysts. This is a rare case of an adult-onset medial canthal capillary haemangioma that was initially misdiagnosed as a dermoid cyst, emphasising the diagnostic challenge posed by such presentations. A 46-year-old female presented with a 10-year history of a painless, slowly progressive swelling over the right medial canthus. The lesion was soft, mobile, non-tender, and measured approximately 0.5×0.5 cm, without associated visual disturbances or discharge. Based on clinical examination, a provisional diagnosis of dermoid cyst was made. The lesion was surgically excised under local anaesthesia, revealing a well-circumscribed, encapsulated soft mass. Histopathological analysis demonstrated proliferation of capillary-sized blood vessels lined by flattened endothelial cells within a fibrous stroma, confirming the diagnosis of capillary haemangioma. The postoperative period was uneventful, and no recurrence was noted at three months follow-up. Adult-onset periorbital haemangiomas are extremely rare, with few cases documented in the literature. Their clinical presentation frequently overlaps with dermoid cysts due to similar location, consistency, and benign nature. Misdiagnosis is therefore common, highlighting the need for a high index of suspicion. Unlike infantile haemangiomas, adult variants do not undergo spontaneous involution and often require surgical excision for definitive management. This case underlines the importance of considering vascular tumours in the differential diagnosis of long-standing periorbital swellings in adults. Accurate diagnosis through histopathological confirmation is essential to avoid mismanagement and contributes to the limited existing literature on this rare clinical entity