J. E. Dornberger, Burn Centre with Plastic Surgery, BG Klinikum Unfallkrankenhaus Berlin, Berlin, Germany.
J. E. Dornberger, A. Eisenschenk, Department of Hand, Replantation and Microsurgery, BG Klinikum Unfallkrankenhaus Berlin, Berlin, Germany.
Clin Orthop Relat Res. 2021 Jan 1;479(1):151-160. doi: 10.1097/CORR.0000000000001425.
Cone beam CT (CBCT) is a widely available technique with possible indications in carpal ligament injuries. The accuracy of CBCT arthrography in diagnosing traumatic tears of the scapholunate ligament has not been reported.
QUESTIONS/PURPOSES: (1) What is the diagnostic accuracy of CBCT and how does it relate to the accuracy of multislice CT arthrography and conventional arthrography in diagnosing scapholunate ligament tears? (2) What is the estimated magnitude of skin radiation doses of each method?
This secondary analysis of a previous prospective study included 71 men and women with suspected scapholunate ligament tears and indications for arthroscopy. Preoperative imaging was conventional arthrography and either MSCT arthrography for the first half of patients to be included (n = 36) or flat-panel CBCT arthrography for the remaining patients (n = 35). Index tests identified therapy-relevant SLL tears with dorsal or complete SLL ruptures, and these tears were compared with relevant SLL tears which were determined through arthroscopy as Geissler Stadium III and IV by probing the instable SL joint with a microhook or arthroscope. These injuries were treated by open ligament repair and Kirschner wire fixation. Accuracy values and 95% confidence intervals were calculated. Additional estimates of the radiation skin doses of each CBCT exam and two MSCT protocols were subsequently calculated using dose area products, dose length products, and CT dose indices.
The diagnostic accuracy was high for all imaging methods. 95% CIs were broadly overlapping and therefore did not indicate differences between the diagnostic groups: Sensitivity of CBCT arthrography was 100% (95% CI 77 to 100), specificity was 95% (95% CI 76 to 99.9), positive predictive value was 93% (95% CI 68 to 99.8), and negative predictive value was 100% (95% CI 83 to 100). For MSCT arthrography, the sensitivity was 92% (95% CI 64 to 99.8), specificity was 96% (95% CI 78 to 99.9), positive predictive value was 92% (95% CI 64 to 99.8), and negative predictive value was 96% (95% CI 78 to 99.9). For conventional arthrography, the sensitivity was comparably high: 96% (95% CI 81 to 99.9). Specificity was (81% [95% CI 67 to 92]); the positive predictive value was 77% (95% CI 59 to 89) and negative predictive value was 97% (95% CI 86 to 99.9). Estimated mean (range) radiation skin doses were reported in a descriptive fashion and were 12.9 mSv (4.5 to 24.9) for conventional arthrography, and 3.2 mSv (2.0 to 4.8) for CBCT arthrography. Estimated radiation skin doses were 0.2 mSv and 12 mSv for MSCT arthrography, depending on the protocol.
Flat-panel CBCT arthrography can be recommended as an accurate technique to diagnose scapholunate ligament injuries after wrist trauma. Estimated skin doses are low for CBCT arthrography and adapted MSCT arthrography protocols.
Level III, diagnostic study.
锥形束 CT（CBCT）是一种广泛应用的技术，在腕部韧带损伤的诊断中有一定的适应证。CBCT 关节造影术诊断月骨三角骨韧带撕裂的准确性尚未报道。
问题/目的：（1）CBCT 的诊断准确性如何，与多层 CT 关节造影和常规关节造影在诊断月骨三角骨韧带撕裂方面的准确性有何关系？（2）每种方法的皮肤辐射剂量估计值是多少？
这是一项先前前瞻性研究的二次分析，包括 71 名男性和女性，怀疑有月骨三角骨韧带撕裂，有行关节镜检查的适应证。术前影像学检查为常规关节造影术，前一半患者行多层 CT 关节造影术（n = 36），后一半患者行平板 CBCT 关节造影术（n = 35）。指数试验以背侧或完全月骨三角骨韧带断裂的治疗相关 SL 韧带撕裂为目标，并通过微钩或关节镜探查不稳定的 SL 关节，将这些撕裂与通过关节镜确定的 Geissler Ⅲ级和Ⅳ级相关 SL 韧带撕裂进行比较。这些损伤通过开放性韧带修复和克氏针固定进行治疗。计算了准确性值和 95%置信区间。随后，使用剂量面积乘积、剂量长度乘积和 CT 剂量指数，对每种 CBCT 检查和两种 MSCT 方案的辐射皮肤剂量进行了额外的估计。
所有影像学方法的诊断准确性均较高。95%置信区间广泛重叠，因此没有表明诊断组之间存在差异：CBCT 关节造影的灵敏度为 100%（95%CI 77 至 100），特异性为 95%（95%CI 76 至 99.9），阳性预测值为 93%（95%CI 68 至 99.8），阴性预测值为 100%（95%CI 83 至 100）。对于多层 CT 关节造影术，灵敏度为 92%（95%CI 64 至 99.8），特异性为 96%（95%CI 78 至 99.9），阳性预测值为 92%（95%CI 64 至 99.8），阴性预测值为 96%（95%CI 78 至 99.9）。常规关节造影术的灵敏度也相当高：96%（95%CI 81 至 99.9）。特异性为（81%[95%CI 67 至 92]）；阳性预测值为 77%（95%CI 59 至 89），阴性预测值为 97%（95%CI 86 至 99.9）。报告了平均（范围）估计的皮肤辐射剂量，常规关节造影为 12.9 mSv（4.5 至 24.9），CBCT 关节造影为 3.2 mSv（2.0 至 4.8）。MSCT 关节造影的估计皮肤剂量取决于协议，为 0.2 mSv 和 12 mSv。
平板 CBCT 关节造影术可作为一种准确的技术，用于诊断腕部创伤后的月骨三角骨韧带损伤。CBCT 关节造影和适应的 MSCT 关节造影方案的估计皮肤剂量较低。
III 级，诊断性研究。
