Choosing the Appropriate Imaging Modality for Pediatric Urologic Disorders

Abstract

Imaging has important role in diagnosis of urinary tract pathologies in pediatric population. The trend in choosing the imaging modality is towards reduced or no radiation exposure and obtaining combined morphological and functional imaging. Prescribing the appropriate imaging technique by referring physician is as essential as performing and interpreting it by radiologist. One of the annoying issues in radiology is performing inappropriate or less useful imaging studies for suspected urologic disorders prescribed by the referring physicians, so it is of great worth to choose the most convenient radiologic examination considering its indication, specificity, limitation, safety, availability and cost.

Objectives:

To develop good practice of the first line imaging modalities as well as further imaging strategy in various pediatric urological disorders among the referring physicians in order to choose the most appropriate technique considering its specificity, safety and availability.

Methods:

This article is based on review of various published papers and articles from international journals.

Result:

Ultrasound is universally the modality of choice in pediatric uroradiology. It is inexpensive, immediate, painless, radiation free, widely available and requires no sedation. Magnetic resonance imaging is the second imaging option after Ultrasound in children. It is radiation free modality and provides both morphologic and functional information. Computerized tomography it is less suitable for routine imaging in pediatrics due to its high radiation dose but it is the modality of choice in the context of blunt abdominal trauma and inadequate ultrasound result for urolithiasis. Plain radiography is used to visualize any radio-opaque objects in the urinary tract and to evaluate the position of stents or drains. Voiding cysto-urethrography provides anatomic and functional information about the urinary bladder and the urethra and is the gold standard for detection of vesico-ureteric reflux. Usage of Intravenous Urography is now in universal decline but can still be used as an alternative in the absence of cross sectional imaging facility. Catheter directed angiography has very limited application in pediatric uroradiology due to the invasive nature and is largely replaced by MR Angiography and CT Angiography. Retrograde urethrography and cystogram are essential for evaluation of urethral abnormalities and are replaced by CT cystography in the context of trauma. Nuclear medicine imaging offers functional information about urinary tract. Positron emitted tomography permits the study of organ function by detecting alterations in biochemical processes that suggest disease before changes in anatomy are apparent therefor important in early detection of cancer and evaluation of effects of cancer therapy.

Conclusion:

Knowledge of indication, specificity, limitation, availability and patient safety of various imaging modalities in suspected urological disorders in pediatric population is essential for referring physicians in order to achieve the correct diagnosis with less risk and expenses to the patients.