In a CT scan, air bubbles are frequently seen, and their sizes and locations may vary [10
]. In this study, we found there was a relationship between the presence of air bubbles and some GERD symptoms such as heartburn.
As heartburn is considered to be the most prevalent problem in patients with recognized GERD, an increase in the probability of heartburn due to an increase in the diameter of air columns in most parts of the esophagus motivates widely different discussions. The dilation of the esophagus in V-LES can be ascribed to the probable concomitancy of lower esophageal sphincter (LES) dysfunction that can cause GERD symptoms. However, the presence of an air column in the whole esophagus and also the significant correlation between the sizes of bubbles and heartburn cannot be justified fully by our present knowledge, especially in SV. Furthermore in our study, there was no history of scleroderma or other diseases which can dilate the esophagus. While the average age of our patients was 59, ED could not be attributed to aging processes. A 2005 case report described a young woman who did not respond to twice-daily doses of Rabeprazole. Following further investigations, the cause was revealed to be air swallowing. Therefore, it may be that persistent heartburn can be caused by aerophagia. This is one hypothesis about the relationship between air bubbles and heartburn, as a major symptom of GERD [12
As was previously noted, in our study, ED was defined as an air column greater than 10 cm in diameter in SV and CV and greater than 15 mm in diameter in V-LES. We observed that if the air bubbles were present in all sections of CT, regardless to their size, the risk for heartburn was greater than when there were only some sporadic air bubbles on CT (OR = 9.42). This finding requires further investigation.
Although there was no significant correlation between regurgitation and the presence of ED, there was a significant correlation between the size of air bubbles in V-LES and the presence of regurgitation. In a review of previous studies, Bredenoord and Weusten [13
] showed that the rate of air swallowing was linked to the size of the intragastric air bubble. They also showed that the number of air swallows was linked to the size of the intragastric air.
Further, although there was no significant correlation between regurgitation and the size of bubbles in other parts of the esophagus, the notable differences between the average size of the air column in patients with regurgitation and patients with no regurgitation motivate the continued careful examination of more cases, especially because the average size in patients with regurgitation was higher. Szczesniak showed that regurgitation caused by GERD, and GERD itself can cause air bubbles in the esophagus, thus we can say that regurgitation can also cause air bubbles.
In our research, taking PPIs was considered a factor that confirmed the presence of previous upper gastrointestinal symptoms. Although there was a significant correlation between taking PPIs and the size of the air bubbles, scrutinizing the mean size of the bubbles in patients who used PPIs and those who didn't use the drug revealed some remarkable findings that suggest the need for repeating the study with more cases. In our study, the mean size of bubbles in patients who did not use PPIs was greater than the group who had previously used this drug. This suggests that taking PPIs decreases the size of the air bubbles and that a history of using PPIs could have an influence on some symptoms, which thus may have also had some influence on our results [14
]. In a previous study, it was shown that some patients generated a distension-induced contractile response in the upper esophageal sphincter that was related to PPIs [15
]. Therefore, it is reasonable to conclude that PPIs can decrease the size and incidence of air bubbles by treating GERD symptoms.
Some minor symptoms of GERD were excluded from analysis, such as toothache that occurred following the consumption of cold or hot food. These minor symptoms were rare and would cause difficulties in a statistical analysis (because of the small amount of data in each group); therefore, we did not include them in our analysis. In a future study, the effects of air bubbles on all symptoms of GERD should be assessed.