The effect of age and sex on esophageal hiatal surface area among normal North American adults using multidetector computed tomography.

The size of the esophageal hiatus is clinically important for preserving the integrity of the lower esophageal sphincter mechanism. The purpose of this study was to systematically establish the mean hiatal surface area (HSA) for normal North American adults under physiologic conditions and assess the relationship between sex and age on HSA. Multi-Detector Computer Tomogram (MDCT) images of the esophageal hiatus in 119 healthy adult subjects (61 males and 58 females with an age range of 24-88 years) were retrospectively analyzed using the multi-planar reconstruction (MPR) technique to directly measure their hiatal length (long axis), width (short axis) and surface area at end inspiration. The mean HSA for males was 2.88 cm, with a standard deviation of 0.74 cm. The mean HSA for females was 2.51 cm, with a standard deviation of 0.68 cm. There was a statistically significant difference in HSA between males and females (p = 0.0053); however, there was no statistically significant difference between the HSA among different age groups (p = 0.8439). Similarly, significant differences between males and females were demonstrated in both the length (p = 0.0263) and width (p = 0.0311) measurements, but there was no evidence of an association of these parameters with age. For the first time, the normal size of the hiatus at end inspiration has been established noninvasively for a population of healthy adults from MDCT images.