磁共振扩散成像诊断颅内表皮样囊肿

目的讨论磁共振扩散成像诊断颅内表皮样囊肿的有用性和特异性。方法分析15例经手术证实的颅内表皮样囊肿磁共振扩散成像的表现，也比较其他MRI序列，包括T1、T2WI、质子密度加权像和快速水抑制反转恢复(fast fluid attenuated inversion recovery FLAIR)序列。结果磁共振扩散成像显示所有肿瘤(15个瘤灶)呈明亮的高信号，肿瘤与周围脑组织和脑脊液形成鲜明的对比；对手术后小的残存肿瘤(4个瘤灶)和复发肿瘤(3个瘤灶)的检出也极其敏感。结论磁共振扩散成像对表皮样囊肿有高度的敏感性和特异性，对手术前的定性诊断和手术后肿瘤的残存以及肿瘤复发的判断起着重要的作用。

Value of difusion-weighted MR imaging in intracranial epidermoids

Objective To evaluate the usefulness and specificity of diffusion weighted imaging (DWI) in the diagnosis of intracranial epidermoid Methods Fifteen patients with surgically proved intracranial epidermoids were evaluated with T 1 , T 2 weighted imaging, proton density weighted imaging and fast fluid attenuated inversion recovery (FLAIR) sequences followed by echo planar DWI Results DWI depicted all tumors ( n =15) as strong hyperintensity relative to CSF and brain tissues DWI was also sensitive in assessing small residual foci ( n =4) and recurrence of tumor ( n =3) Conclusion DWI is highly sensitive and specific in demonstrating epidermoids, and also in postoperatively assessing small residual foci and recurrence of tumors