Radiology of olfactory neuroblastoma

Olfactory neuroblastoma is often misdiagnosed pathologically. The authors reviewed eight such cases in which the pathological findings met strict criteria. These neoplasms are locally invasive in the nose and paranasal sinuses, with frequent intraorbital and intracranial extension as well as distant metastases. A rare primary presentation in the sphenoid sinus-clivus region is described. Computed tomography is the procedure of choice in defining intraorbital extension and is complementary to precision laminagraphy for defining intracranial extension. Angiography frequently shows hypervascularity and may be of further help in assessing intracranial extension.