Background

Split kidney function (SKF) is critical for treatment decision in pediatric patients with hydronephrosis and is commonly measured using renal scintigraphy (RS). Non-contrast-enhanced magnetic resonance urography (NCE-MRU) is increasingly used in clinical practice. This study aimed to investigate the feasibility of using NCE-MRU as an alternative to estimate SKF in pediatric patients with hydronephrosis, compared to RS.

Methods

Seventy-five pediatric patients with hydronephrosis were included in this retrospective study. All patients underwent NCE-MRU and RS within 2 weeks. Kidney parenchyma volume (KPV) and texture analysis parameters were obtained from T2-weighted (T2WI) in NCE-MRU. The calculated split KPV (SKPV) percent and texture analysis parameters percent of left kidney were compared with the RS-determined SKF.

Results

SKPV showed a significant positive correlation with SKF (r = 0.88, p < 0.001), while inhomogeneity was negatively correlated with SKF (r = − 0.68, p < 0.001). The uncorrected and corrected prediction models of SKF were established using simple and multiple linear regression. Bland–Altman plots demonstrated good agreement of both predictive models. The residual sum of squares of the corrected prediction model was lower than that of the uncorrected model (0.283 vs. 0.314) but not statistically significant (p = 0.662). Subgroup analysis based on different MR machines showed correlation coefficients of 0.85, 0.95, and 0.94 between SKF and SKPV for three different scanners, respectively (p < 0.05 for all).

Conclusions

NCE-MRU can be used as an alternative method for estimating SKF in pediatric patients with hydronephrosis when comparing with RS. Specifically, SKPV proves to be a simple and universally applicable indicator for predicting SKF.

Graphical Abstract

中文翻译：

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非增强磁共振尿路造影测量肾积水儿科患者分裂肾功能：与肾闪烁扫描的比较

背景

分裂肾功能 (SKF) 对于肾积水儿科患者的治疗决策至关重要，通常使用肾闪烁扫描 (RS) 进行测量。非增强磁共振尿路造影（NCE-MRU）越来越多地应用于临床实践。本研究旨在探讨与 RS 相比，使用 NCE-MRU 作为评估肾积水儿科患者 SKF 的替代方法的可行性。

方法

这项回顾性研究纳入了 75 名患有肾积水的儿童患者。所有患者均在 2 周内接受 NCE-MRU 和 RS 治疗。肾实质体积 (KPV) 和纹理分析参数通过 NCE-MRU 中的 T2 加权 (T2WI) 获得。将计算的左肾分裂 KPV (SKPV) 百分比和纹理分析参数百分比与 RS 测定的 SKF 进行比较。

结果

SKPV 与 SKF 呈显着正相关（r  = 0.88，p  < 0.001），而不均匀性与 SKF 呈负相关（r  = − 0.68，p  < 0.001）。利用一元线性回归和多元线性回归建立了SKF的未校正和校正预测模型。Bland-Altman 图证明两种预测模型具有良好的一致性。校正后的预测模型的残差平方和低于未校正模型的残差平方和（0.283 vs. 0.314），但不具有统计显着性（p  = 0.662）。基于不同 MR 机器的亚组分析显示，三种不同扫描仪的 SKF 和 SKPV 之间的相关系数分别为 0.85、0.95 和 0.94（ 全部p < 0.05）。

结论

与 RS 相比，NCE-MRU 可作为估计肾积水儿科患者 SKF 的替代方法。具体来说，SKPV 被证明是一个简单且普遍适用的预测 SKF 的指标。

图形概要