San Antonio School of Dentistry, University of Texas Health Science Center, San Antonio, Tex.
Department of Pediatric Dentistry, Araraquara Dental School, São Paulo State University, Araraquara, SP, Brazil.
Am J Orthod Dentofacial Orthop. 2019 Jul;156(1):53-60. doi: 10.1016/j.ajodo.2018.07.024.
Pharyngeal airway space (PAS) assessment has been used in the past for a better understanding of orthodontic and surgical outcomes; however, this analysis could be unreliable. Our objective was to evaluate possible changes in the PAS reading in the same patient from their consecutive cone-beam computed tomography (CBCT) scans.
We evaluated a total of 27 patients' CBCT scans obtained at 2 time points with the use of a standardized acquisition protocol. The mean age at T0 was 31 years (range 17-62 years) and the follow-up records (T1) were taken after 4-6 months. Dolphin Imaging software was used to measure the volumes of the nasopharynx, oropharynx, and hypopharynx. We also evaluated the craniocervical position with the use of a lateral cephalogram.
The variables exhibited high intraclass correlation coefficients (ICCs) when measuring the same CBCT scan twice (T0 and T0). However, The ICC between the measurements performed on the first and second CBCT scans (T0 and T1) showed that the only variable with high reproducibility between the 2 scans was cranial base, with an ICC >0.97. Average differences of 682.1 mm, 2255.3 mm, and 517.4 mm were found for the nasopharynx, oropharynx, and hypopharynx, respectively. Regarding the cephalometric angles, average differences between T0 and T1 scans were 0.6°, 2.7°, and 0.4° for OPT.CVT, OPT.SN, and cranial base, respectively.
Different CBCT exams with equal scanning and patient positioning protocols can result in different 3D PAS readings. A more careful interpretation of CBCT volumetric data to achieve adequate conclusions of the clinical outcomes is necessary.
过去,人们通过评估咽腔气道空间(PAS)来更好地理解正畸和手术的效果;然而,这种分析可能并不可靠。我们的目的是评估同一患者在连续锥形束计算机断层扫描(CBCT)扫描中 PAS 读数的可能变化。
我们共评估了 27 名患者的 CBCT 扫描,这些扫描是在使用标准化采集方案的 2 个时间点获得的。T0 时的平均年龄为 31 岁(17-62 岁),随访记录(T1)在 4-6 个月后获取。使用 Dolphin Imaging 软件测量鼻咽、口咽和下咽的体积。我们还使用侧位头颅侧位片评估颅颈位置。
当两次测量同一 CBCT 扫描(T0 和 T0)时,变量的组内相关系数(ICC)较高。然而,第一次和第二次 CBCT 扫描(T0 和 T1)测量值之间的 ICC 表明,只有颅底在两次扫描之间具有高度可重复性,ICC>0.97。鼻咽、口咽和下咽的平均差异分别为 682.1、2255.3 和 517.4mm。关于头影测量角度,T0 和 T1 扫描之间的平均差异分别为 OPT.CVT、OPT.SN 和颅底的 0.6°、2.7°和 0.4°。
具有相同扫描和患者定位方案的不同 CBCT 检查可能会导致不同的 3D PAS 读数。为了得出临床结果的充分结论,需要更仔细地解释 CBCT 体积数据。