METHODS: Forty-six patients with pathologically proven PAs and 47 schwannomas in the parapharyngeal space were enrolled. All patients underwent conventional MRI, and DW-MRI and DCE-MRI were performed in 30 and 33 patients, respectively. Fisher\'s exact, Mann-Whitney-U tests and Independent samples t-test were used to compare variables between PAs and schwannomas. Multivariate logistic regression analysis was used to examine the diagnostic performance of MRI parameters.
RESULTS: The PAs usually show lobulation sign, posterior displacement of ICA and attached to the parotid gland deep leaf, while bird beak configuration, anterior displacement of ICA and involvement of foramen jugular were more commonly seen in the schwannomas(all p < 0.001). The washout rate of PAs was found to be higher than that of schwannomas (p = 0.035), whereas no significance was found in the other DCE-MRI parameters and in ADCs(p > 0.05). Using a combination of conventional MRI features including lobulation sign, bird beak configuration, direction of internal carotid artery(ICA) displacement and attached to the parotid gland in multivariate logistic regression analysis, sensitivity, specificity, and accuracy in differential diagnosis of PAs and schwannomas were 97.8%, 91.5% and 94.6%, respectively.
CONCLUSIONS: Conventional MRI can effectively differentiate PAs from schwannomas in the parapharyngeal space with a high diagnostic accuracy. The DCE-MRI and DWI have limited added diagnostic value to conventional MRI in the differential diagnosis.
方法:纳入46例经病理证实的PAs和47例咽旁间隙神经鞘瘤患者。所有患者均接受常规MRI检查,在30和33例患者中进行了DW-MRI和DCE-MRI,分别。费希尔的精确,使用Mann-Whitney-U检验和独立样本t检验来比较PAs和神经鞘瘤之间的变量。多因素logistic回归分析用于检查MRI参数的诊断性能。
结果:PA通常显示分叶征,ICA后移并附着于腮腺深叶,而鸟嘴配置,ICA前移位和颈静脉孔受累在神经鞘瘤中更常见(均p<0.001)。发现PAs的洗脱率高于神经鞘瘤(p=0.035),而在其他DCE-MRI参数和ADC中没有发现显著性(p>0.05)。结合常规MRI特征,包括分叶征,鸟嘴配置,颈内动脉(ICA)位移方向和与腮腺的连接在多因素logistic回归分析中,灵敏度,特异性,PAs和神经鞘瘤的鉴别诊断准确率为97.8%,91.5%和94.6%,分别。
结论:常规MRI可有效鉴别咽旁间隙神经鞘瘤和PAs,诊断准确率高。DCE-MRI和DWI对常规MRI的鉴别诊断价值有限。