Fluid-fluid levels in cystic lumbosacral schwannomas: a report of three cases.

Magnetic resonance imaging features of three benign cystic lumbosacral schwannomas, which showed multiple fluid-fluid levels, are described. One of the tumours showed bone destruction with fluid-fluid levels that closely mimicked an aneurysmal bone cyst. Pathological examination confirmed haemorrhage as the cause of fluid-fluid levels in the tumours. Though a rare finding, fluid-fluid levels with bone destruction can also be caused by nerve sheath tumours and hence must be included in the list of differential diagnoses of spinal tumours.