Liu Nai-Chieh, Troconis Eileen L, McMillan Matthew, Genain Marie-Aude, Kalmar Lajos, Price David J, Sargan David R, Ladlow Jane F
Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
College of Veterinary Medicine, Cornell University, Ithaca, NY.
Vet Radiol Ultrasound. 2018 May;59(3):289-304. doi: 10.1111/vru.12590. Epub 2018 Jan 15.
Computed tomography (CT) is used to document upper airway lesions in dogs with brachycephalic obstructive airway syndrome. The presence of an endotracheal tube during CT scanning is often required for general anesthesia. We hypothesized that the endotracheal tube placement would change the soft tissue dimensions of the upper airway. The aims of this prospective, method comparison study were to evaluate the reliability of the previously reported upper airway CT measurements with endotracheal tube placement, and to propose measurements that are minimally affected by the endotracheal tube. Twenty brachycephalic dogs were included in this study. Each dog underwent head/neck CT with an endotracheal tube, followed by a second scan without the endotracheal tube. Ten measurements of the soft palate, nasopharynx, and trachea were performed. Tracheal dimension was significantly larger with the endotracheal tube compared to without, whereas the soft palate cross-sectional area was significantly smaller with the endotracheal tube than without the endotracheal tube. The influence of the endotracheal tube on the caudal nasopharynx cross-sectional (transverse-sectional) area varied with a mean proportional absolute difference of 35%. Rostral soft palate thickness, tracheal perimeter, and cross-sectional area of the rostral nasopharynx were the measurements least affected by the endotracheal tube (intraclass correlation coefficient = 0.964, 0.967, and 0.951, respectively). Therefore, we proposed that these three measurements may be most useful for future brachycephalic obstructive airway syndrome studies that require CT scanning of intubated animals. However, with endotracheal tube placement, measurements of soft palate length, caudal nasopharyngeal cross-sectional area, and trachea height and width may not be reliable.
计算机断层扫描（CT）用于记录患有短头阻塞性气道综合征的犬的上气道病变。CT扫描期间通常需要放置气管插管以进行全身麻醉。我们假设气管插管的放置会改变上气道的软组织尺寸。这项前瞻性方法比较研究的目的是评估先前报道的气管插管放置情况下上气道CT测量的可靠性，并提出受气管插管影响最小的测量方法。本研究纳入了20只短头犬。每只犬在放置气管插管的情况下进行头/颈部CT扫描，然后在不放置气管插管的情况下进行第二次扫描。对软腭、鼻咽和气管进行了10次测量。与不放置气管插管相比，放置气管插管时气管尺寸明显更大，而放置气管插管时软腭横截面积明显小于不放置气管插管时。气管插管对鼻咽尾端横截面积的影响各不相同，平均比例绝对差异为35%。软腭前端厚度、气管周长和鼻咽前端横截面积是受气管插管影响最小的测量指标（组内相关系数分别为0.964、0.967和0.951）。因此，我们建议这三项测量指标可能对未来需要对插管动物进行CT扫描的短头阻塞性气道综合征研究最有用。然而，在放置气管插管的情况下，软腭长度、鼻咽尾端横截面积以及气管高度和宽度的测量可能不可靠。
