中耳胆脂瘤的影像诊断:高分辨率计算机断层成像与磁共振成像的比较研究

目的:评估和比较高分辨率计算机断层成像(high resolution computer tomography,HRCT)与磁共振成像(magnetic resonance imaging,MRI)对中耳胆脂瘤的诊断价值。方法:回顾性分析临床初步诊断为中耳胆脂瘤患者55人(63耳)在术前5天内进行的16排HRCT和1.5T MRI诊断结果,以病理诊断为基础对HRCT和MRI的诊断结果进行对比研究,统计分析HRCT和MRI的灵敏度、特异度、阳性预期值、阴性预期值,以及Kappa检验两者之间的内在观察一致性。结果:63耳中,病理确诊为中耳胆脂瘤40耳。HRCT正确诊断30例,假阳性11例,假阴性10例,灵敏度、特异度、阳性预期值以及阴性预期值分别为75%、52.17%、73.17%、54.55%。MRI正确诊断37例,假阳性和假阴性各为3例,灵敏度、特异度、阳性预期值以及阴性预期值分别为92.5%、86.96%、75%和86.96%。HRCT与MRI诊断结果之间的内在观察一致性Kappa=0.274(P0.05)。剔除既往有手术史的10耳,只针对无手术史的53耳,HRCT与MRI诊断结果之间的内在观察一致性增高,吻合度一般,Kappa=0.462(P0.05)。结论:MRI的总体阳性检出率高于HRCT,尤其是对中耳胆脂瘤手术后复发的诊断;HRCT与MRI两者相结合对于中耳胆脂瘤的明确诊断具有互补作用。

Imaging Diagnosis of Middle Ear Cholesteatoma: Comparative Study on High Resolution Computed Tomography and Magnetic Resonance Imaging

Objective:To evaluate and compare the value of high resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) in the diagnosis of middle ear cholesteatoma.Methods:Retrospectively analyzed 55 patients (63 ears) with clinically suspected middle ear cholesteatoma who received both 16-slice HRCT and 1.5T MR scanning within 5 days before operation. HRCT and MRI were compared based on pathology and performed statistical analysis. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of HRCT and MRI were calculated and the inter-observer agreement between both was assessed with the kappa value.Results:Among 63 ears, 40 ears were diagnosed as middle ear cholesteatoma by pathology. By HRCT, 30 ears having middle ear cholesteatoma were identified correctly. The false positive was 11 and the false negative was 10. The sensitivity, specificity, PPV and NPV of HRCT were 75%, 52.17%, 73.17% and 54.55%, respectively. In contrast, 37 ears having middle ear cholesteatoma were identified correctly by MRI. Both the false positive and the false negative were 3. The sensitivity, specificity, PPV and NPV of MRI were 92.5%, 86.96%, 75% and 86.96%. The inter-observer agreement between HRCT and MRI was poor, Kappa=0. 274 (P<0.05). Removing 10 post-operative ears, only for the 53 non-operated ears, the inter-observer agreement between HRCT and MRI raised, Kappa=0.462 (P<0.05).Conclusion:The total positive rate of MRI was higher than HRCT, especially for post-operative recurrence. The combination of HRCT and MRI had a complementary role in diagnosis of middle ear cholesteatoma.