SPECT／CT同机融合显像检测鼻咽癌侵犯颅底骨的临床价值

Clinical value of 99Tcm-MDP SPECT/CT in diagnosing skull base bone involvement ofnasopharyngeal carcinoma

目的 探讨99Tcm-亚甲基二膦酸盐（MDP）SPECT结合定位CT对鼻咽癌（NPC）颅底骨侵犯（SBBI）检测能力及临床价值。方法 对165例鼻咽癌初治患者于放疗前同期进行99Tcm-MDP SPECT结合定位CT鼻咽颅底断层骨显像和MRI检查。于SPECT/CT图像矢状面，颅底放射性浓聚程度最高（L）层面与高位颈椎体（C1-C3，S）处勾画相同大小的感兴趣区（ROI），计算其放射性摄取比值，L/S〉1提示SBBI。以MRI结果为标准，采用双盲法对两者检测结果进行比较。根据肿瘤的不同侵犯途径，进一步把颅底骨分斜坡、岩尖、蝶骨体、蝶窦底和翼突、翼板等区域进行统计分析。结果 SPECT/CT检测SBBI总体灵敏度、特异性、准确度、阳性预测值、阴性预测值、к值分别为96.74%（89/92）、72.60%（53/73）、86.06%（142/165）、81.65%（89/109）、94.64%（53/56）、0.711，ROC曲线下面积0.847，差异有统计学意义（Z=12.436，P〈0.01）；斜坡、岩尖区域的阳性预测值（91.67%）明显高于蝶骨体、蝶窦底区域和翼突、翼板区域的阳性预测值（30.00%、14.29%）。结论 99Tcm-MDP SPECT/CT能有效地检测鼻咽癌SBBI，尤其在斜坡、岩尖区域，与MRI检测结果高度一致。

Objective To evaluate the diagnostic value of 99Tcm-methylene diphosphonate（MDP）SPECT/CT in skull base bone involvement （SBBI） of nasopharyngeal carcinoma （NPC）.Methods Whole-body and skull-base tomography 99Tcm-MDP SPECT/CT and MRI were applied in 165 untreated NPC patients. The radioactive counts within a region of interest （ROI） of suspected SBBI （L） were delineated from the sagittal plane of SPECT images. The radioactive counts within a same size ROI of upper cervical vertebra C1 to C3（S） were also analyzed. The ratio of L and S （L/S） was calculated. L/S 〉 1 indicates SBBI.MRI data was used as a standard control. The results were double-blind compared and evaluated.In addition, SBBI was further analyzed in different regions,includingthe clivus and petrous apex region of the skull base, the base of sphenoid bone and sphenoid sinus region, the Pterygoid process and lamina lateralis and lamina medialis region. Results The sensitivity, specificity, accuracy, positive predictive value, negative predictive value and κ value for SBBI detection by SPECT/CT were 96.74%（89/92）, 72.60%（53/73）, 86.06%（142/165）, 81.65%（89/109）, 94.64%（53/56） and 0.711, respectively. The area under the ROC （receiver operating characteristic） curve （AUC） was 0.847, which showed statistically significant difference （Z=12.436, P〈0.01）. In the SBBI evaluation by SPECT/CT for different regions, the positive predictive value of SPECT/CT for SBBI detection in the clivus and petrous apex region of the skull base was significantly higher than that in the base of sphenoid bone, sphenoid sinus region, the pterygoid process, lamina lateralis and lamina medialis region （91.67% vs. 30.00%,14.29%） Conclusions 99Tcm-MDP SPECT/ CT could be used for the detection of nasopharyngeal SBBI, especially in the clivus and petrous apex region of the skull base. The test results were highly consistent with the MRI findings.