Chronic intradiploic hematomas of the skull without coagulopathy: Report of two cases.

BACKGROUND Chronic intradiploic hematoma was first described by Chorbski and Davis in 1934. To date, only twelve cases have been reported in the literature. Chronic intradiploic hematomas have also been described as non-neoplastic cysts of the diploe, traumatic cysts, and giant cell repetitive granulomas. The term chronic intradiploic hematoma was coined by Sato et al. in 1994. CASE DESCRIPTION Case 1: a 16-year-old male presented with a non-tender scalp swelling on the right fronto-orbital region. Computed tomography (CT) scans showed an intraosseous isodense lesion with surrounding sclerosis. Magnetic resonance imaging (MRI) results revealed an intradiploic mass with homogeneous cystic and abnormal signal intensities. Case 2: a 64-year-old male presented with a 6-month history of headaches and visual disturbances. CT scans showed an isodense lesion with surrounding sclerosis in the posterolateral left orbit. MRI results revealed a hypointense lesion on both the T1weighted and T2-weighted images of the posterolateral left orbit. CONCLUSION Although rarely seen, the presence of a benign chronic hematoma should be considered as part of the differential diagnosis for each intradiploic mass lesion. When taking the medical history, all patients with such mass lesions should be asked about previous minor or major head traumas. Due to the possibility of progressive growth, surgical excision of an intradiploic hematoma is recommended after radiological diagnosis of the condition.