Related Experiment Video
Updated: May 16, 2026

Simultaneous Laryngopharyngeal and Conventional Esophageal pH Monitoring
Published on: December 14, 2020
Nasal backflow and the difficulty of relaxation in the upper esophageal sphincter
Jin-Woo Park1, Bum Sun Kwon, Ji Hae Chang
1Department of Physical Medicine and Rehabilitation, Dongguk University Ilsan Hospital, Gyeonggi-do, Republic of Korea. jinwoo.park.md@gmail.com
Objectives/Hypothesis:
Nasal backflow is the regurgitation of material into nasopharynx during swallowing and it can be easily observed by videofluoroscopy. We aimed to evaluate the association between nasal backflow and the prevalence of aspiration, as well as the relationship between nasal backflow and the opening of the upper esophageal sphincter.
Study Design:
Retrospective case-control study.
Methods:
There were 182 cases of videofluoroscopic swallowing studies that were retrospectively reviewed. The presence of nasal backflow and laryngeal aspirations were checked, and the anteroposterior maximum width of the upper esophageal sphincter opening was measured on lateral images of videofluoroscopic swallowing studies. The difference in maximum upper esophageal sphincter width between the group with nasal backflow and the group without nasal backflow was statistically verified.
Results:
Twenty patients showed nasal backflow, which was closely related to laryngeal aspiration (odds ratio = 10.97; 95% CI = 2.46-48.85; P < 0.05). Their maximal upper esophageal sphincter width (mean ± standard deviation) was 6.82 ± 1.96 mm and significantly different from the group without nasal backflow (9.35 ± 1.56 mm) (P < 0.05).
Conclusion:
Nasal backflow was closely associated with the presence of aspiration; the opening of upper esophageal sphincters significantly decreased in the cases of nasal backflow.
Related Concept Videos
Esophageal Achalasia
Gastroesophageal Reflux Disease
Gastroesophageal Reflux Disease I: Meaning and Pathophysiology
Esophageal Strictures-I: Introduction
Etiology
The primary cause of esophageal strictures is long-standing gastroesophageal reflux disease (GERD), accounting for about 70 to 80% of adult cases. Chronic acid reflux can lead to injury and scarring of the esophageal lining, culminating in...
Hiatal Hernia
Gastroesophageal Reflux Disease II: Clinical Features and Management
Clinical Manifestations
GERD presents itself in a multitude of ways, with symptoms varying from person to person. The hallmark symptoms are...
