Renogram (Lasix)

Indication

• This procedure is indicated in patients with dilated collecting systems (Hydronephrosis and Hydroureter) to distinguish which systems are obstructed and may require operative reconstruction from those which are dilated but not obstructed. The procedure is particularly useful for assessing the significance of residual urinary tracer dilation after pyeloplasty or ureteral neocystostomy.

Contraindications

• Patients who are dehydrated.

Radiopharmaceuticals

• 10 mCi Tc 99m MAG-3 IV

Pharmaceutical

• Furosemide 0.3 mg/kg to 0.5 mg/kg administered intravenously slowly over a period of one to two minutes.

Patient Preparation

• Patient should be normally hydrated. Administration of intravenous diuretics is contraindicated in dehydrated patients. Patient should void immediately prior to beginning the study. In some pediatric patients where distal ureteral obstruction is suspected, a catheter should be placed in the urinary bladder and allowed to drain freely in order to prevent bladder accumulation of radioactivity which may superimpose and obscure the distal ureters.

Procedure

• Place the patient supine on the scintibed table centered over the detector.
• Inject the radiopharmaceutical as a bolus.
• Image the patient in the posterior projection in a supine position so as to include the kidneys, ureters, and bladder.
• 40 minutes of images.