Kidney Diagnostics (Renal scintigraphy)

Nierenszintigraphie-top-01-936The renal scintigraphy is a special examination of the two separate sides of the renal blood flow or renal function and the renal excretion performance of both. With the renal scintigraphy, pathological changes in the kidney can be detected (e.g., inflammation, tumors, urinary retention, and high blood pressure control after renal transplantation).


Other names: renal scintigraphy, renal clearance

Used contrast agents: Tc-99m Mag3 (Mercaptylacetyltriglycine)

What is a renal scintigraphy?

The renal scintigraphy is a nuclear medical examination procedure for the assessment of each side of the kidneys’ renal function (renal clearance), the urine flow into the bladder. It also allows for the assessment of the kidney location, its shape, and size. The examination measures the renal excretion of the radioactive substance by the kidneys. Disturbances of the renal function can be detected at an early stage, even before they are noticed in laboratory tests. 

When is this examination needed (indication)?

With this examination consequences of disease on renal blood flow, renal function and excretion can be estimated at an early stage, such as:

  • Recognition of general renal dysfunction after kidney disorders (e.g., inflammation, tumors)
  • For separate assessment of renal perfusion and function such as in living kidney donors or from kidney surgery
  • Diagnosis of urinary obstruction
  • Assessment of the relevance of stenosis of the renal arteries (possible cause of high blood pressure)
  • In renal transplant for clinical monitoring of renal function
  • In infants with abnormalities of the urinary tract to study the urinary flow

How is the examination performed?

It is a non-invasive examination, in which the patient receives an injection into the vein. The substance accumulates quickly in the kidney tissue and, which is positioned in the back of the patient lying mostly recorded. Based on the speed of excretion of the substance is not only the total

This substance accumulates rapidly in the renal tissue and then discharged. Over a period of about 40 mintues, images are recorded with a gamma camera that is positioned in the back of the patient (patients will for the most part lie down during the examination).

NiereInjNeu2Based on the speed of excretion of the substance, not only the total renal function can be accessed accurately, but also for each kidney, the percentage of the function can be calculated separately.  In addition, urinary obstruction, such as in an expanded renal pelvis, a renal pelvic tightness or ureter stenosis can be documented.

Is a special preparation necessary for the exam?

Special preparations on the part of the patient are not required. However, about 30 minutes prior to the actual examination, the patient should drink about 1 liter of fluid, enough to achieve a good urinary flow.

Radiographic contrast medication should not have been administered within the 48 hours prior to the exam since the results could otherwise be distorted.


Does medication have to be discontinued before the exam?

In general, medications should not be discontinued prior to the exam. For specific problems, specific blood pressure lowering drugs, could possibly distort the results. If in doubt, please ask beforehand.


Are there side effects?

The drug is usually well tolerated; side effects (such as dizziness, flushing, headache) and allergic reactions are extremely rare and are usually only moderate.


When should the examination not be conducted (contraindications)?

The only contraindication is pregnancy or breastfeeding.


How high is the radiation exposure?

Since the radioactive substance is used in very low doses and is excreted quickly, radiation exposure will be very low and is comparable to the exposure of a normal X-ray.


Who pays for the examination?

The renal scintigraphy is a standard benefit of all statutory and private health insurance.