Pyloric volume: an important factor in the surgeon's ability to palpate the pyloric "olive" in hypertrophic pyloric stenosis.

OBJECTIVE

The objective of this study was to determine whether the size of the pyloric mass is one of the factors in the surgeon's ability to palpate the pyloric "olive".

MATERIALS AND METHODS

The ultrasonographic images and medical records of 60 infants with surgically confirmed hypertrophic pyloric stenosis (HPS) were reviewed. The pyloric diameter (PD) and pyloric length (PL) were measured and the pyloric volume (PV) was calculated using the equation PV = 1/4pi x (PD)2 x PL. Based on the pediatric surgeon's physical examination the infants were divided into two groups: those with and those without palpable pyloric masses.

RESULTS

Infants with a palpable pyloric mass had an average pyloric volume of 3.33 +/- 1.76 mm3, which was statistically larger than those whose hypertrophied pylorus could not be palpated (average volume 2.59 +/- 2.07 mm3, P < 0.01). There was no statistically significant age difference between the two groups.

CONCLUSION

Clinical skill of the examiner and other clinical aspects (patient cooperation, etc.) determine palpability of the pylorus in HPS. The size of the hypertrophied pylorus is also an important factor affecting the clinician's ability to palpate the pyloric mass.