METHODS: Patients (n = 81) with the diagnosis of a plasma cell dyscrasia and whole-body DLCT at the time of diagnosis and follow-up were retrospectively enrolled. CI, CaSupp25, and CaSupp100 were quantitatively analyzed using regions of interest in the lumbar vertebral bodies and fractured vertebral bodies on baseline or follow-up imaging. VCa were calculated by subtraction (CaSupp100-CaSupp25), delineating bone only. Logistic regression analyses were performed to assess the possibility of imminent spine fractures.
RESULTS: In 24 patients, new vertebral fractures were observed in the follow-up imaging. The possibility of new vertebral fractures was significant for baseline assessment of CT numbers in CI, CaSupp25, and VCa (p = 0.01, respectively), with a higher risk for new fractures in the case of lower CT numbers in CI (Odds ratio = [0.969; 0.994]) and VCa (Odds ratio = [0.978; 0.995]) and in the case of higher CT numbers in CaSupp 25 (Odds ratio 1.015 [1.006; 1.026]). Direct model comparisons implied that CT numbers in CaSupp 25 and VCa might show better fracture prediction than those in CI (R2 = 0.18 both vs. 0.15; AICc = 91.95, 91.79 vs. 93.62), suggesting cut-off values for CI at 103 HU (sensitivity: 54.2%; specificity: 82.5; AUC: 0.69), for VCa at 129 HU (sensitivity: 41.7%; specificity: 94.7; AUC: 0.72).
CONCLUSIONS: Quantitative assessment with CaSupp and calculation of VCa is feasible to predict the vertebral fracture risk in MM patients. DLCT may prove useful in detecting imminent fractures.
方法:患者(n=81)在诊断和随访时被诊断为浆细胞发育不良和全身DLCT。CI,CaSupp25和CaSupp100在基线或随访成像时使用腰椎椎体和骨折椎体中的感兴趣区域进行定量分析。VCa通过减法计算(CaSupp100-CaSupp25),只描绘骨头。进行Logistic回归分析以评估即将发生脊柱骨折的可能性。
结果:在24名患者中,在随访影像中观察到新的椎体骨折。新椎体骨折的可能性对于CI,CaSupp25和VCa的CT数量的基线评估具有重要意义(分别为p=0.01),在CI(赔率比=[0.969;0.994])和VCa(赔率比=[0.978;0.995])较低的情况下,以及在CaSuppp25(赔率比1.015[1.006;1.026])较高的情况下,新发骨折的风险较高。直接模型比较表明,CaSuppp25和VCa的CT数字可能比CI中的CT数字显示更好的骨折预测(R2=0.18,两者与0.15;AICc=91.95,91.79vs.93.62),建议CI在103HU时的临界值(灵敏度:54.2%;特异性:82.5;AUC:0.69),对于129HU的VCa(灵敏度:41.7%;特异性:94.7;AUC:0.72)。
结论:使用CaSuppp进行定量评估并计算VCa可以预测MM患者的椎体骨折风险。DLCT可能被证明可用于检测即将发生的骨折。