Accuracy of Sonographic Renal Pelvic Diameter in Assessment of Renal Function among Patients with Ureteropelvic Junction Obstruction using Scintigraphy as a Gold Standard.

Objectives: The study aimed to assess the diagnostic accuracy of sonographic renal pelvic diameter (RPD) in pediatric patients with ureteropelvic junction obstruction (UPJO) and its potential as a solo diagnostic tool. The study also looked for a clinically meaningful cutoff point in sonographic RPD, with the goal of optimizing sensitivity and specificity for discriminating between normal and impaired renal function in UPJO cases. Materials and methods: The study, which took place at a maternity and child hospital, involved 75 children under the age of three who had been diagnosed with UPJO. Data was collected from 2020 to 2022 using both ultrasonography and renal scintigraphy, with cases diagnosed using only one modality being excluded. Results: The analysis included descriptive and t-tests. The results demonstrated a significant difference in sonographic RPD between pediatric patients with normal and impaired renal function and with large and normal renal diameters. The average renal pelvis diameter was found to be 2.2 ±1.9 cm. The sensitivity and specificity of sonographic RPD for predicting impaired renal function in UPJO vary significantly across multiple cutoff points, underlining RPD's diagnostic potential. Conclusion: The study concluded that combining two modalities (ultrasound and scintigraphy) improves results when the renal pelvic diameter surpasses 1 cm.