Hyalinised hepatic hemangioma

Hyalinised hepatic hemangiomas, also known as sclerosing/sclerosed hepatic hemangiomas, are a rare variant of hepatic hemangioma. Because of their unusual imaging features, they cannot be reliably differentiated from a malignant tumor without a biopsy. Liver capsular retraction is a common feature of these lesions.

Pathology

A hyalinised hemangioma differs from a typical hemangioma by containing extensive fibrous tissue and obliterated/thrombosed vascular channels. Some consider a hyalinisation to be a stage in hemangioma involution. A hemangioma that is only partially fibrosed is described as "sclerosing". A completely fibrosed hemangioma is described as "sclerosed".

Radiographic features

MRI

• T1: hypointense
• T2: variable T2 signal intensity, less than that of a typical hemangioma
  • increasing sclerosis/fibrosis appears to correspond with increasing T2 hypointensity
• T1+C (Gd)
  • absent or mild arterial phase-contrast enhancement
    • decreased enhancement with more advanced sclerosis
  • slight peripheral enhancement may occur in the late phase
  • peripheral enhancement is usually a thin rim, compared with nodular discontinuous enhancement
• T1+C (Eovist): not described

Capsular retraction has been described in some hyalinised/sclerotic hemangiomas. Wedge-shaped transient hepatic intensity differences (THIDs) may be present in the adjacent liver.

Differential diagnosis

A hyalinised hemangioma cannot be reliably be differentiated from a hepatic malignancy on MRI, and biopsy is necessary for differentiation .