脊索样脑膜瘤的影像学表现

目的探讨脊索样脑膜瘤的影像学表现。方法回顾性分析6例经手术病理证实的脊索样脑膜瘤患者的CT和MRI。6例中4例接受CT,其中2例接受CT平扫和增强扫描,1例仅接受平扫、1例仅接受增强扫描;5例接受MR平扫及增强扫描,其中2例接受动态增强MRA检查。结果 4例病灶位于幕上,1例位于幕下桥小脑角区,1例跨小脑幕上下生长。3例侵犯邻近组织。3例伴瘤周水肿。3例病灶CT平扫分别呈低、等、高密度;5例病灶平扫MR T1WI均呈低信号,T2WI 4例呈高信号。4例MR增强检查中病灶明显强化,3例见脑膜尾征。2例MRA动脉期肿瘤均未见显影,其中1例静脉期肿瘤显影,1例MRA全程未见显影。结论脊索样脑膜瘤女性多见,发病年龄较轻;肿瘤好发于幕上,T2WI呈高信号;增强后强化明显,且呈延迟强化;易侵袭邻近组织,尤其是骨组织,但较少突破软脑膜侵袭脑实质。

Imaging appearances of chordoid meningioma

Objective To investigate imaging appearances of chordoid meningioma (CM). Methods CT and MRI of 6 patients with pathologically proved CM were retrospectively analyzed. Four cases were scanned with CT, among them 2 underwent plain scan and contrast enhanced scan, 1 underwent only plain scan, and the rest 1 underwent contrast enhanced scan. Five patients underwent plain and contrast enhanced MRI, among them 2 underwent dynamic MRA. Results Four lesions located supratentorially, 1 located at cerebellopontine angle, 1 located across the tentorium. Peritumoral edema and nearby tissue invasion were seen in 3 cases. Three cases showed as low, iso- and high density on plain CT, respectively. The lesions showed hypointensity on T1WI in 5 cases, hyperintensity on T2WI in 4 cases. Dense enhancement was seen in 4 cases. The "dural tail" was observed in 3 cases. On dynamic contrast-enhanced MRA, both lesions were not seen on artery phase, 1 was seen and another was not seen in venous phase. Conclusion CM has preponderance of young women, which generally locate supratentorially and show hyperintensity on T2WI. On gadolinium-enhanced T1WI, marked and delayed enhancement can be observed. Adjacent tissue invasion can be found in CM patients, especially bone destruction, but the lesions rarely invade brain parenchyma.