Table 1 Different clinical scenarios and imaging guideline

Perinatal urinary tract dilatation

Ultrasound

After sonographic detection of UTD, MCUG may be required for detection of VUR or PUV

If reflux is found, Tc-99m-DMSA scintigraphy is the investigation of choice for functional

If VUR is not encountered, so obstruction is the probable cause of UTD for dynamic renal scintigraphy

MRI also can be requested especially in complex renal anomalies (robust anatomical and functional capabilities)

Recurrent urinary tract infection

Ultrasound in infants below two years or present with atypical or recurrent UTI

MCUG in all children with abnormal ultrasound or atypical or recurrent UTI

MCUG, and if positive, DMSA scintigraphy; Or DMSA scintigraphy and if positive MCUG

Enuresis and daytime urinary incontinence

Screening ultrasound (pre-void and post-void scan)

MRI of the spine is reserved for children with suspected abnormalities of the lumbosacral spine

MR urography can be of value in detection of structural anomalies particularly ectopic ureter

IVP may be of value if the access to MRI is limited

Abdominal masses

Following ultrasound, cross-sectional imaging with CT or MRI is mandatory for further evaluation and initial staging

CT enables simultaneous evaluation of both lungs

MRI is more sensitive in detecting contralateral synchronous masses

Flank pain

Ultrasound and radiography

Low-dose non-contrast CT should be reserved when ultrasound is non-diagnostic or further anatomical details are needed for surgical intervention

Hematuria

Ultrasound

Subsequent imaging depends on the initial ultrasound findings

Trauma

Ultrasound is the first modality for trauma surveillance especially in patients with minimal symptoms

Four-phase post-contrast CT of the urinary tract (Pre- and post-contrast phases in arterial, nephrographic and pyelographic phases)

Nonpalpable testis, ambiguous genitalia and common urogenital sinus anomalies

General guidelines recommend against preoperative imaging of nonpalpable testis

Ultrasound and or MRI in cases of ambiguous genitalia

Genitogram represents the main preoperative radiological assessment in urogenital sinus anomalies, some centres may add pelvic MRI

Renovascular hypertension

Ultrasound with Doppler is the initial imaging modality

CT or MR angiography are the recommended further imaging modalities

Catheter angiography after failure of medical therapy for hypertension or when ultrasound reveals size discrepancy between both kidneys, or in children with neurofibromatosis