双能量CT能谱曲线预测甲状腺乳头状癌颈部中央区淋巴结隐匿性转移的价值

Value of Dual-energy CT Spectrum Curve from Primary Tumor in Prediction of Central Occult Lymph Node Metastasis in Papillary Thyroid Cancer

目的通过分析甲状腺乳头状癌(PTC)癌灶的双能量CT能谱曲线,预测颈部中央区隐匿性淋巴结转移(OLM)的概率,为临床手术方式的制定提供参考。方法回顾性收集术前行双能量CT扫描,且术后病理证实为PTC的患者。由放射医师分析CT图像,未检出颈部淋巴结转移者共140例。其中病理证实有中央组淋巴结隐匿性转移者(OLM+)88例、无转移者(OLM−)52例。测量PTC癌灶各单能量图像上的CT值并计算能谱曲线斜率k,分析2组间各参数的差异。结果(1)动静脉期OLM+组与OLM−组之间PTC癌灶的k_(arterial)、40 keV_(arteria)l、40 keV_(venous)、160 keV_(venous)、180 keV_(venous)差异有统计学意义(P均<0.050);(2)比较40 keV_(arteria)l、karterial、40 keV_(venous)、160 keV_(venous)、180 keV_(venous)的诊断效能,AUC分别为0.590、0.622、0.590、0.429、0.424,当k_(arterial)=2.563时,诊断PTC肿瘤伴中央组OLM的敏感度及准确度分别为93.2%、69.3%;当40 keV_(venous)=370.25时,诊断PTC肿瘤伴中央组OLM的特异度为86.5%。结论PTC癌灶的能谱曲线预测颈部中央区隐匿性淋巴结转移的有一定的参考价值,其中k_(arterial)诊断的敏感度最高、40 keV_(venous)诊断的特异度最高。

Objective To predict the probability of occult lymph node metastasis(OLM)in the central region of the neck by analyzing the dual-energy CT energy spectrum curve of thyroid papillary carcinoma(PTC).Methods Patients with PTC confirmed by pathology before and after operation were retrospectively collected.CT images were analyzed by radiologists.There were 140 cases without cervical lymph node metastasis.Among them,88 patients with occult lymph node metastasis in the central group(OLM+)and 52 patients without metastasis(OLM−)were confirmed by pathology.The CT value of PTC on each single energy image was measured and the slope(k)of the energy spectrum curve was calculated.The differences in parameters between the two groups were analyzed.Results(1)the k_(arterial),40 keV_(arteria)l,40 keV_(venous),160 keV_(venous) and 180 keV_(venous) of PTC between OLM+group and OLM−group in arterial and venous phase were significantly different(P<0.05).(2)The AUC of 40 keV_(arteria)l,k_(arterial),40 keV_(venous),160 keV_(venous) and 180 keV_(venous) in PTC were 0.590,0.622,0.590,0.429 and 0.424 respectively.When k_(arterial)=2.563,the sensitivity and accuracy of diagnosing PTC with OLM in the central group were 93.2%and 69.3%.When 40 keV_(venous)=370.25,the specificity of PTC with OLM was 86.5%.Conclusion The energy spectrum curve of PTC has a certain reference value in predicting occult lymph node metastasis in the central region of the neck.k_(arterial) has the highest sensitivity and 40 keV_(venous) has the highest specificity.