COMPUTED TOMOGRAPHY OF THE PHARYNX IN A CLOSED VS. OPEN MOUTH POSITION
Article first published online: 7 MAR 2011
© 2011 Veterinary Radiology & Ultrasound
Veterinary Radiology & Ultrasound
Volume 52, Issue 4, pages 357–361, July/August 2011
How to Cite
LAURENSON, M. P., ZWINGENBERGER, A. L., CISSELL, D. D., JOHNSON, L. R., McPETERS, M. J., SPRIET, M. P., TAYLOR, S. L. and POLLARD, R. E. (2011), COMPUTED TOMOGRAPHY OF THE PHARYNX IN A CLOSED VS. OPEN MOUTH POSITION. Veterinary Radiology & Ultrasound, 52: 357–361. doi: 10.1111/j.1740-8261.2011.01805.x
- Issue published online: 19 JUL 2011
- Article first published online: 7 MAR 2011
- Received November 13, 2010; accepted for publication January 17, 2011.
The pharynx is anatomically complex and evaluation can be difficult even with cross-sectional imaging. Eight animals had computed tomography (CT) studies of the head performed with the mouth open and closed. The studies were anonymized and evaluated by four radiologists for visibility of six anatomic regions (dorsal wall of nasopharynx, lumen of nasopharynx, dorsal margin of the soft palate, ventral margin of the soft palate, oropharynx, and laryngopharynx) and for certainty of a normal or abnormal diagnosis of four different anatomic regions (nasopharynx, soft palate, oropharynx, and laryngopharynx). Mean visual scores differed significantly between mouth positions and were improved when the mouth was open. The ability of radiologists to classify anatomic regions as normal or abnormal vs. unsure also varied between mouth positions, and there was greater uncertainty when the mouth was closed. In addition, estimated volume of the air-filled nasopharynx differed significantly as a function of mouth position and was greater when the mouth was open (mean=1.187 cm3, SE=0.177) vs. closed (mean=0.584 cm3, SE=0.116). Computed tomographic evaluation of the pharynx can be improved with the mouth open.