Abstract

Background:
The renal collecting system comprises the minor calyces, major calyces, infundibula, and renal pelvis, which together facilitate urine drainage into the ureter.

Aim:
This study aimed to analyze morphological variations of the renal pelvicalyceal system with respect to the position of the renal pelvis and patterns of calyceal drainage in a cadaveric population.

Methods:
This descriptive cadaveric study was conducted on 50 kidneys obtained from 25 cadavers over 3 years. The pelvicalyceal system was exposed by careful dissection, and variations were classified based on the position of the renal pelvis according to the Sampaio and Ningthoujam classification systems. Data are expressed as frequency and percentage.

Results:
An intrarenal pelvis was observed in 23 (46%) specimens, followed by borderline pelvis in 12 (24%) and extrarenal pelvis in 8 (16%). Absence of renal pelvis was noted in 7 (14%) specimens. According to Sampaio’s classification, type AI was the most common (25, 50%). Based on the Ningthoujam classification, the bicalyceal pattern was the most frequent (27, 54%). A rare variation of extrarenal calyces with absent pelvis was observed in 1 (2%) specimen.

Conclusion:
The morphology of the renal pelvicalyceal system has significant variability. Awareness of these variations may aid in accurate radiological interpretation and endourological procedure planning. However, the findings should be interpreted in light of the limitations of cadaveric studies.

Key words: Anatomical variation; Cadaveric study; Calyceal pattern; Pelvicalyceal system; Renal pelvis.