Falkowski Anna L, Kovacs Balazs K, Schwartz Fides R, Benz Robyn M, Stieltjes Bram, Hirschmann Anna
Department of Radiology, University Hospital Basel, University of Basel, Petersgraben 4, 4031, Basel, Switzerland.
Department of Radiology, Orthopedic University Hospital Balgrist, University of Zurich, Forchstrasse 340, 8008, Zurich, Switzerland.
Skeletal Radiol. 2020 Dec;49(12):1965-1975. doi: 10.1007/s00256-020-03508-7. Epub 2020 Jun 18.
To compare fracture detection, image quality, and radiation dose in patients with distal extremity fractures using 3D tomography and computed tomography (CT).
IRB approval was obtained including informed consent for this prospective study from June to December 2016. Patients diagnosed with an acute fracture at CT were consecutively scanned on the same day using 3D tomography. Anatomical location (effected bone and location within the bone) and morphological characteristics of fractures (avulsion, articular involvement, mono- vs. multifragmented, displacement), visibility of bone/soft tissue structures, and image quality were assessed independently by two blinded readers on a 5-point Likert scale. Dose-length-product (DLP; mGy*cm) was compared between both modalities. Descriptive statistics, Wilcoxon signed rank test (P < 0.05), Student's t test (P < 0.05), and Cohen's kappa (κ) for interreader reliability were calculated.
In 46 patients (28 males; 18 females; mean age, 53 ± 20 years) with 28 hand/wrist and 18 foot/ankle examinations, 86 out of 92 fractures were diagnosed with 3D tomography compared with CT. No false-positive finding occurred at 3D tomography. The six missed fractures on 3D tomography were five avulsion fractures of the carpals/metacarpals or tarsals/metatarsals, respectively, and one nondisplaced fracture of the capitate. Interreader agreement of anatomical location and morphological characteristics was substantial to almost perfect for upper (κ = 0.80-0.96) and lower (κ = 0.70-0.97) extremity fractures. Visibility of bone and soft tissue structures and image quality were slightly inferior using 3D tomography compared with CT (upper extremity P < 0.001-0.038 and lower extremity P < 0.001-0.035). DLP of a comparable scan coverage was significantly lower for 3D tomography (P < 0.001) for both upper (3D mean, 19.4 ± 5.9 mGycm; estimated CT mean, 336.5 ± 52.2 mGycm) and lower extremities (3D mean, 24.1 ± 11.1 mGycm; estimated CT mean, 182.9 ± 6.5 mGycm). Even the highest DLP with 3D tomography was < 30% of the mean estimated CT dose of a comparable area of coverage.
Fracture assessment of peripheral extremities is reliable utilizing a low-dose 3D tomography X-ray system, with slightly reduced image quality.
比较使用三维断层扫描和计算机断层扫描（CT）对四肢远端骨折患者进行骨折检测、图像质量和辐射剂量的情况。
本前瞻性研究于2016年6月至12月获得机构审查委员会（IRB）批准，包括患者的知情同意。在CT检查中诊断为急性骨折的患者于同一天连续接受三维断层扫描。两名不知情的阅片者独立使用5分李克特量表评估骨折的解剖位置（受累骨骼及骨骼内位置）、骨折的形态学特征（撕脱、关节受累、单块与多块、移位情况）、骨/软组织结构的可视性以及图像质量。比较两种检查方式的剂量长度乘积（DLP；mGy*cm）。计算描述性统计量、威尔科克森符号秩检验（P < 0.05）、学生t检验（P < 0.05）以及阅片者间可靠性的科恩kappa（κ）系数。
46例患者（28例男性；18例女性；平均年龄53 ± 20岁）接受了28次手部/腕部和18次足部/踝部检查，92处骨折中有86处通过三维断层扫描诊断出来，与CT诊断结果相比差异无统计学意义。三维断层扫描未出现假阳性结果。三维断层扫描漏诊的6处骨折分别为5处腕骨/掌骨或跗骨/跖骨的撕脱骨折以及1处头状骨的无移位骨折。对于上肢（κ = 0.80 - 0.96）和下肢（κ = 0.70 - 0.97）骨折，阅片者在解剖位置和形态学特征方面的一致性为实质性到几乎完美。与CT相比，使用三维断层扫描时骨和软组织结构的可视性以及图像质量略差（上肢P < 0.001 - 0.038，下肢P < 0.001 - 0.035）。对于上肢（三维平均，19.4 ± 5.9 mGycm；估计CT平均，336.5 ± 52.2 mGycm）和下肢（三维平均，24.1 ± 11.1 mGycm；估计CT平均，182.9 ± 6.5 mGycm），三维断层扫描在可比扫描范围内的DLP显著更低（P < 0.001）。即使三维断层扫描的最高DLP也小于可比覆盖区域估计CT平均剂量的30%。
使用低剂量三维断层扫描X射线系统对周围四肢骨折进行评估是可靠的，但其图像质量略有下降。
