The impact of pelvicalyceal anatomy on the stone formation in patients with lower pole renal stones.

BACKGROUND

The aim of our study was to determine whether various anatomic factors constitute a predisposition to a lower pole renal stones.

MATERIALS AND METHODS

We analysed the computed tomography (CT) urography of 75 patients with a single lower pole stone. Measurements were taken of the infundibulopelvic angle (IPA), infundibular width (IW), infundibular length (IL) and calyceopelvic height (CPH).

RESULTS

The mean patient age was 50 years (range 17-79 years). The mean stone size was 11.9 mm. The mean IPA using Sampaio method in affected kidney was 113.4 ± 15.3o (range 80-139o), 59.5 ± 17.3o using Elbahnasy method. The values of IPA on the contralateral kidney were 119.86 ± 15.37o (range 79-141o; p = = 0.001) using Sampaio method of measurement and 59.78 ± 12o (range 34-90 o; p = 0.465) using the method described by Elbahnasy. We reported statistically significant differences between stone-bearing kidney and contralateral kidney in measurement IPA using only Sampaio method. The mean infundibular width was 4.22 ± 1.81 mm on the affected kidney and 3.72 ± 2.5 mm on the contralateral side (p = 0.164). The mean infundibular length was 15.37 ± 4.57 mm on the affected kidney and 14.66 ± 4.35 mm on the unaffected side (p = 0.329). The CPH was 10.19 ± 4.05 mm on the affected kidney and 10.44 ± 3.83 mm on the normal side (p = 0.688).

CONCLUSIONS

Pelvicalyceal morphology of the kidney is one of the factors that determine the risk of developing kidney stones. Out of the analysed morphological parameters of kidney IPA is a statistically significant risk factor to form lower pole kidney stones. Other anatomic parameters did not seem to have a significant role in predisposing to form lower pole kidney stone. (Folia Morphol 2018; 77, 1: 16-21).