Czaja J M, McCaffrey T V
Department of Otorhinolaryngology, Mayo Clinic, Rochester, MN 55905, USA.
Ann Otol Rhinol Laryngol. 1996 Jul;105(7):504-9. doi: 10.1177/000348949610500702.
A device that determines cross-sectional area (CSA) of the airway by acoustic reflections (Hood, Inc) was used to measure subglottic area. Airway models were made from Plexiglas rings with known internal dimensions similar to clinically encountered stenoses of various lengths and diameters. Acoustic measurements of airway area were made and compared to actual CSA. There is a strong correlation between CSA measured acoustically and the actual area of simulated stenoses. However, when the CSA of the stenosis was < 0.64 cm2, the signal was impaired, resulting in overestimation of the stenotic CSA. In simulated stenoses with a CSA of < 0.38 cm2, acoustic measurement of the CSA beyond the stenotic segment was unreliable. Determination of the origin of stenosis was accurate with this method. The CSA of cadaver airways was also measured acoustically. The CSA 2.0 cm below the glottis of normal airways in males ranged from 1.28 to 2.74 cm2 and in females 0.87 to 1.43 cm2, with means of 2.16 and 1.09 cm2. It appears that acoustic measurement of CSA of subglottic stenosis is a feasible clinical technique that yields dimensions of the airway in situations in which direct measurements are impossible. It was suggested that this technique be used for assessment of subglottic stenosis and evaluation of the efficacy of treatment of subglottic stenosis.
一种通过声学反射测定气道横截面积（CSA）的设备（胡德公司）用于测量声门下面积。气道模型由有机玻璃环制成，其内部尺寸已知，类似于临床上遇到的各种长度和直径的狭窄。对气道面积进行声学测量并与实际CSA进行比较。声学测量的CSA与模拟狭窄的实际面积之间存在很强的相关性。然而，当狭窄的CSA<0.64平方厘米时，信号受损，导致狭窄CSA被高估。在CSA<0.38平方厘米的模拟狭窄中，狭窄段以外的CSA声学测量不可靠。用这种方法确定狭窄的起源是准确的。还对尸体气道的CSA进行了声学测量。男性正常气道声门以下2.0厘米处的CSA范围为1.28至2.74平方厘米，女性为0.87至1.43平方厘米，平均值分别为2.16和1.09平方厘米。看来，声门下狭窄CSA的声学测量是一种可行的临床技术，在无法进行直接测量的情况下能够得出气道尺寸。有人建议将该技术用于声门下狭窄的评估以及声门下狭窄治疗效果的评估。
