CT and MRI findings of sinonasal hemangiopericytoma / 中华放射学杂志

ABSTRACT

Objective To determine the CT and MRI features of the sinonasal cavity. Methods The CT and MRI of nine patients with histologically proved hemangiopericytoma in the sinonasal cavity were retrospectively reviewed. All nine patients underwent CT and seven of them underwent MRI. In addition, the time-intensity curve (TIC) of dynamic contrast-enhanced (DCE) MRI were analyzed in three patients. Results The lesions were from the nasal cavity in 5 cases, the maxillary sinus in 3 cases, and the sphenoid sinus in one case. The lesions appeared spindle in 4 cases, oval in 3, and irregular in 2. The mean maximum diameter of the lesions was 31 mm (range, 15 to 52 mm). Seven hemangiopericytomas had welldefined margins and 2 had ill-defined margins. On plain CT, the lesions were isodense to gray matter in six (66. 7% ) and slightly hyperdense in three (33. 3% ) patients. Only two patients had post-contrast CT and the tumors showed marked enhancement. The lesions caused adjacent bony compression and absorption in 7 cases and bony destruction in 2. On MR T1WI, hemangiopericytomas appeared hypointense in 3 (42. 8% ) patients and isointense in 4 (57. 2% ) patients. On T2WI, the lesions appeared hyperintense in three (42.8%) patients and isointense in four (57.2%) patients. On T1WI, all the lesions showed relatively homogeneous signal, while 2 lesions revealed heterogeneous signal on T2WI. Hemangiopericytomas showed marked homogeneous contrast enhancement in 4 cases and heterogeneous contrast enhancement in 3.TIC showed a steady enhancement pattern in 3 patients. The lesions involved the orbit in 2 cases and,cavernous sinus, anterior skull base meninge, pterygopalatine fossa and infratemporal fossa in one case. Five patients underwent follow-up for two to eight years after surgery. Two patients were found to have recurrence.Conclusions Marked enhancement and steady enhancement pattern of TIC on MRI are typical manifestations of hemangiopericytoma of the sinonasal cavity. Bone changes may help to identify the nature of the lesion. Imaging can accurately detect the scope of hemangiopericytoma in this region.