3.0T磁共振成像对听神经瘤的诊断及与病理学检查结果的对照分析

Diagnosis of acoustic neuroma:3.0T magnetic resonance imaging versus pathology

目的 3.0T磁共振成像(3.0 tesla magnetic resonance imaging,3.0T MRI)可应用于对听神经瘤的诊断。文中用3.0T MRI对听神经瘤进行诊断,探讨听神经瘤的MRI表现,结合病理学检查结果,提高手术前对听神经瘤的认识。方法回顾性分析22例行MR检查和手术病理证实的听神经瘤患者。使用西门子Magnetom Trio 3.0T磁共振仪,采用扫描方法为MR平扫梯度回波序列(FL2D)的T1加权成像、自旋回波序列(TSE)的T2加权成像、扩散加权成像及增强后的T1加权成像。对神经瘤肿块的大小、形态、位置、坏死、囊变、信号强度及其增强程度等MRI各种表现分别观察和记录,重点观察实性肿块和囊性肿块的病理学特点,将MR表现和病理学检查结果进行对照分析。结果 22例听神经瘤中,MRI示实性肿块15例,占68.2%,瘤体在T1WI及T2WI呈等信号,病理表现主要以梭形的Antoni A型细胞为主。囊实性肿块6例,占27.3%,呈T1WI等低、T2WI等高的混杂信号,病理表现为伴黏液变性的Antoni B型细胞为主,并混有Antoni A型细胞。出血性肿块1例,占4.5%,呈T1WI等高、T2WI等低的混杂信号。增强扫描示肿块实性部分均明显强化,囊变部分不强化。22例患侧的听神经均增粗、强化。结论 MRI能客观显示听神经瘤的病理学特点,为制定手术方案提供重要信息。

Objective 3.0-tesla （3.0T） MRI has an important value in the diagnosis of acoustic neuroma. This study aimed to investigate the MRI manifestations of acoustic neuroma based on the findings of 3.0T MRI and histopathology in order to improve the preoperative identification of the tumor. Methods We retrospectively analyzed 22 cases of acoustic neuroma confirmed by MRI and histopathologic examinations. The patients underwent 3.0T MRI scanning, the scan sequences mainly including T1 weighted imaging （WI） with FL2D, T2WI with FSE and diffusion WI （DWI） on unenhanced routine SE sequence and T1 -WI on enhanced MRI. We ob- served the size, appearance, site, necrosis, cystic change, signal intensity, degree and pattern of the tumors, and compared the MRI findings with histopathologic results, particularly the pathologic basis of solid and cystic masses. Results Among the 22 cases of acoustic neuroma, MRI revealed 15 solid masses （68.2%）, with homogeneous isointensity on T1 and T2 WI, 6 cystic masses （27.3%）. with heterogeneous hvoo- or isointensitv on T, WI and heterogeneous iso- or hvnerintensitv on T. WI. and 1 hemorrhagicmass, with heterogeneous iso- or hyperintensity on T1 WI and heterogeneous iso- or hypointensity on T2 WI. Histopathology showed mainly antoni A spindle cells in the solid mass and chiefly antoni B cells with mucinous degeneration in the cystic mass. Enhanced MRI manifested obvious enhancement on the solid parts but not on thecystic cases components of the masses, while enhanced TI WI exhibited ipsilateral auditory nerve thickening and enhancement in all lhe Conclusion MRI can objectively demonstrate the pathologie features of acoustic neuroma and provide valuable information tot