Kosalagood Pasupen, Silkosessak Onanong C, Pittayapat Pisha, Pisarnturakit Pagaporn, Pauwels Ruben, Jacobs Reinhilde
Department of Radiology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand.
Oral Imaging Center, OMFS-IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, University of Leuven, Leuven, Belgium.
Clin Implant Dent Relat Res. 2015 Dec;17(6):1217-27. doi: 10.1111/cid.12221. Epub 2014 Mar 28.
Information regarding linear accuracy is necessary for efficient treatment evaluation, especially for maxillofacial reconstruction or implants.
To investigate the accuracy of linear measurements from multiple cone beam computed tomography (CBCT) devices.
A RANDO® phantom was scanned with eight CBCT scanners (11 modes). The viewing software accompanying each scanner was employed for measurements in mediolateral, anteroposterior, and supero-inferior dimensions by two dentomaxillofacial radiologists. Digital caliper measurements were used as a "gold standard." ANOVA with Scheffé post hoc analysis and intraclass correlation coefficient (ICC) were utilized for statistical analyses. The level of confidence was 95%.
Differences from the gold standard among 11 acquisition modes were statistically significant (p < .001). Measurements from one unit were always underestimated compared with all others (p < .001). The range of absolute measurement errors for tested units was -2.56 to 0.54 mm (mean ± SD 0.45 ± 0.71) including the outlier and -0.34 to 0.54 mm (0.16 ± 0.11) excluding the outlier. Slightly more values were underestimated than overestimated (41 of 66 measurements, 7 out of 11 CBCT modes). ICC scores for inter- and intraobserver agreement were perfect (1.000).
Treatment planning from large-volume CBCT was found to be reliable in all except one of the investigated scanners. New CBCT scanners should always be tested for geometric accuracy.
对于有效的治疗评估，尤其是颌面重建或植入物，有关线性精度的信息是必要的。
研究多台锥形束计算机断层扫描（CBCT）设备线性测量的准确性。
使用八台CBCT扫描仪（11种模式）对RANDO®体模进行扫描。两名口腔颌面放射科医生使用每台扫描仪附带的观察软件在内外侧、前后和上下维度进行测量。数字卡尺测量用作“金标准”。采用方差分析和谢费尔事后分析以及组内相关系数（ICC）进行统计分析。置信水平为95%。
11种采集模式与金标准之间的差异具有统计学意义（p <.001）。与所有其他设备相比，一台设备的测量值总是被低估（p <.001）。测试设备的绝对测量误差范围为-2.56至0.54毫米（平均值±标准差0.45±0.71）（包括异常值）和-0.34至0.54毫米（0.16±0.11）（不包括异常值）。被低估的值略多于被高估的值（66次测量中的41次，11种CBCT模式中的7种）。观察者间和观察者内一致性的ICC评分均为完美（1.000）。
除一台被调查的扫描仪外，发现大容量CBCT的治疗计划在其他所有扫描仪上都是可靠的。新的CBCT扫描仪应始终进行几何精度测试。
