Objective: To determine whether the MR finding of cysts along the intracranial margin of sinonasal esthesioneuroblastomas can be considered to suggest this tumor.

Methods: MR scans of 54 patients who had sinonasal lesions with intracranial extension were examined specifically for cysts along the intracranial margins of the lesions.

Results: Only 3 of the 54 patients had these cysts, and all 3 of these patients had esthesioneuroblastoma. Surgical pathologic findings of one specimen showed the cyst to be marginally located within the tumor.

Conclusions: If cysts are seen on MR along the intracranial margin of a sinonasal mass, this finding highly suggests esthesioneuroblastoma.