Norm of Magnetic Resonance Urography
Usage of Magnetic Resonance Urography
Identification of urinary tract dilation, particularly after transplantation; detection of neurogenic bladder dysfunction, ectopic ureters in children; alternative to intravenous pyelography and computed tomography in renal-impaired clients for whom excretory urography is contraindicated, such as those with uremia and renal impairment or those with no excretory function. Helpful during pregnancy and in those clients allergic to contrast medium, because of the noninvasive nature of the procedure. Other usage should be reserved for those clients in which less expensive testing has proven inconclusive.
Description of Magnetic Resonance Urography
Magnetic resonance urography (MRU) is a costly but extremely accurate, noninvasive, and noncontrast method of identifying renal conditions which are not well identified with other technology such as computed tomography, pyelography, and ultrasound. In MRU, urine appears white, and so the adequacy of the excretory route and obstructive impairments can be evaluated. The MRU may be enhanced with the use of the breath-hold method, using intravenous gadolinium (Gd).
Professional Considerations of Magnetic Resonance Urography
Consent form IS required.
- See Preparation, Magnetic resonance imaging.
- Client must be well-hydrated before the procedure.
- The client is positioned supine on the MRU table and an antenna is coiled around the abdomen.
- Noncontrast method:
- a. A scout MRU is performed to locate the kidneys and ureters and then is used as a guide to acquire multiple images of the urinary system.
- Breath-hold method:
- a. An intravenous injection of 10 mL of gadolinium chelate is followed by fast-spoiled, gradient echo sequences acquired during breath-holding at 5, 10, and 15 minutes.
- The collecting system is evaluated according to a scale of 0 to 3.
- See Postprocedure Care, Magnetic resonance imaging.
Client and Family Teaching
- MRU is used to evaluate whether there are obstructions in the kidneys and ureters.
- See Client and Family Teaching, Magnetic resonance imaging.
Factors That Affect Results
- See Factors That Affect Results, Magnetic resonance imaging.
- Insufficient hydration will reduce the quality of the results.
- MRU with contrast has been used to evaluate renal tumors and to evaluate the upper urinary tract in children.