Evaluation of differential renal function in children - a comparative study between magnetic resonance urography and dynamic renal scintigraphy.

BACKGROUND: Urinary system anomalies, both congenital and acquired, constitute a relatively common clinical problem in children. The main role of diagnostic imaging is to determine early diagnosis and support therapeutic decisions to prevent the development of chronic renal disease. The aim of this study was to evaluate the utility of magnetic resonance urography (MRU) in assessment of urinary system in children, by comparing differential renal function calculated using MRU with dynamic renal scintigraphy (DRS). MATERIALS AND METHODS: The study group consisted of 46 patients aged 1 week to 17 years (median 7 (0.5; 13) years, 17 (37%) girls, 29 (63%) boys), who underwent dynamic renal scintigraphy due to various clinical reasons. All participants underwent MRU, which was used to measure differential renal function. Functional analysis was performed using dedicated external software (CHOP-fMRU and pMRI without prior knowledge of DRS results. MRU results acquired using pMRI were assessed for inter and intraobserver agreement. RESULTS: Statistical analysis of the results showed excellent agreement between MRU and DRS in measuring differential renal function with Pearson correlation coefficient 0.987 for CHOP-fMRU and 0.971 for pMRI, p < 0.001. Interclass correlation coefficient (ICC) for these programs was 0.987 (95% CI 0.976-0.993) and 0.969 (95% CI 0.945-0.983) respectively, p < 0.001. The Bland-Altman 95% limits of agreement for CHOP-fMRU results vs. DRS was - 6.29-5.50 p.p. and for pMRI results vs. DRS - 9.15-9.63 p.p. The differential renal function measurements calculated in pMRI showed excellent intraobserver and interobserver agreement with ICC 0.996 (95% CI 0.994-0.998) and 0.992 (95% CI 0.986-0.996) respectively, p < 0.001. CONCLUSIONS: The study showed no significant differences between magnetic resonance urography and dynamic renal scintigraphy in calculating differential renal function. It indicates high utility of MRU in the evaluation of urinary system in children.

Magnetic Resonance Characteristics of Baló Concentric Sclerosis in Children.

BACKGROUND: Baló concentric sclerosis is a rare demyelinating disease with characteristic magnetic resonance appearance of multilayered ringlike lesions of demyelination. This disease is extremely rare in children. We present the clinical data, radiological appearance, and development of lesions in eight children. METHODS: We analyzed the clinical information of eight patients diagnosed between 2012 and 2020. Magnetic resonance brain and spinal cord examinations with contrast medium administration were performed using a 1.5-T scanner. RESULTS: All patients presented at least one typical Baló lesion on brain imaging. Four patients additionally had typical multiple sclerosis plaques. All primary Baló lesions had a characteristic appearance of concentric hyperintense rings on T2-weighted imaging and were round or ovoid. Cerebrospinal fluid analysis was performed in all patients. Oligoclonal bands were present in seven patients, and four of them had multiple sclerosis plaques on baseline brain magnetic resonance imaging. CONCLUSION: Baló concentric sclerosis in children is characterized by acute and severe onset with hemiparesis as a predominant symptom. The size, contrast enhancement, and restricted diffusion depend on the phase of the disease.