Revision 29 for 'Giant hepatic venous malformation'All Revisions
Giant hepatic venous malformation
There is poor agreement in the literature as to the exact definition of what constitutes a giant hepatic hemangioma (also known as giant hepatic (slow flow) venous malformations as some of the literature defines as a size > 4 cm but others >6 or even >10 cm. Either way they are examples of atypical hepatic hemangiomas 3.
Many are asymptomatic, however hemorrhage, thrombosis and mass effect may lead to abdominal fullness and pain. Depending on location and size compressive effects on adjacent structures (biliary dilatation or vascular structures) may also lead to presentation.
Hemorrhage and/or rupture (following trauma/biopsy typically) may also be encountered.
May contains areas of central necrosis/liquefaction, hemorrhage, peripheral calcification, fibrosis and thrombosis.
Giant hemangiomas may demonstrate similar findings to their smaller relatives, although findings are less consistent.
On non contrast scans the lesions are usually heterogeneous hypo-attenuating masses with marked central areas of low attenuation.
Typical enhancement pattern is of peripheral nodular enhancement that gradually fills centrally and follows aortic density (same as smaller hemangiomas).
Contrast filling may be slow and the central portions may never be demonstrated to fill in. Occasionally they may have no contrast enhancement.
Capsular retraction from scaring may also be seen.
- sharply marginated hypo intense mass
- cleft like areas of low signal intensity
- cleft like area may remain hypo intense during enhancement
- enhancement pattern is otherwise similar to that seen on CT
- T2: cleft area may be markedly T2 hyper intense
Treatment and prognosis
Potential complications include:
- mass effect on adjacent structures (e.g. biliary tree, hepatic vessels)
- Kasabach-Merritt syndrome 4 (form of consumptive coagulopathy due to thrombocytopaemia)