Quantitation of stone burden: Imaging advances

The accurate diagnosis and quantitation of nephrolithiasis in patients with primary hyperoxaluria (PH) often directly impacts the medical and surgical management for individuals with both symptomatic and asymptomatic calculi. Traditionally, depiction of the size, location and appearance of urinary calculi has been provided by kidney, ureter and bladder plain film radiographs with or without tomography. Given advances in imaging technology there is a shift from conventional radiographs to cross-sectional imaging technology, namely unenhanced computed tomography (CT), CT urography, ultrasound and magnetic resonance imaging. These diagnostic techniques provide differing advantages and disadvantages for imaging stone disease. This review outlines imaging advances in the accurate diagnosis and quantitation of patients with metabolically active stone disease such as PH.