Exorenal circulation of pediatric kidney: evaluation with Power Doppler imaging

Area of Science:

• Pediatric Radiology
• Vascular Imaging
• Renal Physiology

Background:

• Assessing renal collateral circulation is crucial for understanding kidney health in children.
• Power Doppler (PD) sonography offers a non-invasive method to evaluate blood flow.
• Limited data exists on pediatric renal collateral visualization and its changes in disease states.

Purpose of the Study:

• To evaluate Power Doppler (PD) sonography's ability to demonstrate kidney collateral circulation in pediatric patients.
• To assess changes in collateral circulation in children with reduced cortical blood flow, such as in acute pyelonephritis (APN).

Main Methods:

• Seventy-seven children were studied using PD sonography.
• The study identified capsular and perforating collateral vessels.
• Participants were categorized into three age groups: neonates, 1 month–2 years, and 2–15 years, including healthy subjects and those with APN or prenatal pyelectasia.

Main Results:

• PD sonography successfully visualized perforating vessels and the exorenal arcade in all neonates and infants.
• In children with APN, an increased caliber of capsular vessels surrounding avascular areas was observed.
• Vessel caliber and number decreased with age in healthy children, with visualization in younger age groups (2-15 years).

Conclusions:

• Exorenal circulation is visible in normal pediatric kidneys using PD sonography.
• Renal collateral vessel caliber and number are highest in neonates and decrease with age.
• Hypoperfused conditions, like extensive APN, can lead to significant variations in pediatric renal vascularity.