鼻腔、鼻窦血管外皮瘤的CT和MRI表现

目的 探讨鼻腔、鼻窦血管外皮瘤的CT和MRI表现.方法 回顾性分析9例经组织学证实鼻腔、鼻窦血管外皮瘤的CT(9例)和MRI(7例)资料,并分析其中3例动态增强扫描的TIC.结果 血管外皮瘤位于鼻腔5例、上颌窦3例,蝶窦1例;病变呈梭形4例、类圆形3例,不规则形2例,病灶最大径18～52 mm,平均31 mm,边界清楚7例,模糊2例.CT表现:与脑灰质比较,平扫病变呈等密度6例,略高密度3例,2例增强后呈较均匀的显著强化;邻近骨质受压、吸收7例,骨质侵蚀破坏2例.MRI表现:与脑灰质比较,T1WI呈较均匀低信号、T2WI呈高信号3例,T1WI、T2WI均呈等信号4例,其中2例信号不均匀;增强后显著均匀强化4例,不均匀强化3例.3例TIC均为持续上升型.病变侵犯眼眶2例,侵犯海绵窦、前颅底脑膜及翼腭窝、颞下窝1例.5例随访3～8年,其中2例复发.结论 MRI增强后显著强化、持续上升型TIC是鼻腔、鼻窦血管外皮瘤较典型的影像表现;骨质表现有助于良、恶性判断;影像检查能够准确显示病变的范围.

CT and MRI findings of sinonasal hemangiopericytoma

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.