Flow and Function Renal Scan

Indications:
  • Evaluation for renal artery stenosis
  • Evaluation for RVH (renovascular hypertension)
  • Evaluation of renal tubular function
  • Kidney transplant evaluation
  • Obstruction of one or both of the renal tubules
Contraindications:
  • Patient has not discontinued ACE inhibitors
  • Patient is pregnant or breast feeding

Questions asked in Patient History:

Do you have a family hx of cancer? If so then what type and how long?
Do you have a hx of kidney disease?
Do you have both kidneys?
Did you have any recent or planned operations?
Do you have any pain? If so then where is it and how long have you had it?
Are you experiancing any nausea or vomiting?
Are you experiancing any urinary frequency or urgency?
Do you have any blood in the urine?
Are you diabetic?
Do you have any hx of cardiac diseases?
Do you have a hx of hypertension?
Do you have the results of any recent lab work?

Radiopharmaceutical information:
  • Radionuclide: Tc-99m or I-131
  • Radiopharmaceutical: Tc-99m MAG3, Tc-99m DTPA, Tc-99m GH
  • Adult dosing:
        • Tc-99m MAG3: 3-5mCi
        • Tc-99m DTPA: 15mCi
        • Tc-99m GH: 20mCi

  • Pediatric dosing: 100 uCi
  • Method of administration: Bolus injection
  • Method of Localization: active transport
  • Physical Half-life: 6 hrs

Patient Preparation:
  • Identify the patient (name and DOB)
  • Explain the procedure to the patient
  • Instruct the patient to hydrate (300-500mL of water)
  • Void before the scan
  • Have the patient stop any diuretics that he or she is taking
  • have the patient wear comfortable clothing with no metal or a gown

Side Effects:
No physical side effects for the procedure

Equipment Used:
Type of Camera or Probe:
Gamma camera

Collimator used:
LEHR

Acquisition Setup:
Photopeak(s): 140 keV

Window(s): 25%

Blood Flow: View(s): native kidney: posterior, transplant kidney: anterior

Matrix: 64x64
Time/Frame: 1-2 seconds/frame
Number of Frames or Duration: 60 seconds


Dynamic: View(s):
native kidney: posterior, transplant kidney: anterior
Matrix: 64x64
Time/Frame: 30 seconds/frame
Number of Frames or Duration: 25 minutes

Statics: View(s):
pre-void and post-void

Matrix: 64x64
Total Counts or Duration: 500k counts/image

Whole body: View(s)
Matrix: N/A
Scan Speed: N/A
Start/stop points: N/A

SPECT:
180 or 90 degree configuration
Total Rotation: N/A
Starting point: N/A
Matrix: N/A
Time/Azmuiths: N/A
Number of Azmuiths: N/A

Processing:
Filter: Butterworth
Cut-off: .4
Frequency:


Procedure:
  1. Lay the patient supine on the table
  2. Position the camera so that it is facing the patients kidneys posteriorly if native kidneys are present with no defects
  3. If there are any defects in the patients kidneys such as horseshoe kidney, pelvic kidney, polycystic disease, ileal loop, any masses that may change the position of the kidney, or foreshortening position the camera so that it faces anterior to the kidneys.
  4. Prepare the MAG3 injection
  5. Start the camera
  6. Immediately after starting the camera, bolus the MAG3 injection
  7. If bolus is is good the slope of you time activity curve should be steep, no activity persisting in the heart and lungs, and immediate visualization of the kidneys should be present.
  8. Image as soon as you see abdominal aortic uptake within 2-5 sec of the bolus injection
  9. At the 1-3 min marker paraenchymal tissue will be visualized
  10. Acquire blood flow images 1-2 sec/frame for 60 sec to evaluate renal perfusion of the kidneys
  11. Immediately after acquiring blood flow, begin dynamic imaging 30 sec/frame for 25 minutes to visualize renal clearance
  12. Obtain pre-void and post-void statics of 500k counts each.
  13. Analyze the TAC (time activity curve) to observe the renal flow and function.
  14. A normal TAC would usualy give you a 60:40 renal function for both kidneys and would give you two slopes that peak then go back down.
  15. An abnormal TAC would for example give you a 65:35 renal function while the one of the two slopes representing the functioning kidney will peak and go back down while the other slope would peak and remain that way.



Normal Uptake and common varients:
IMAG0001-1.jpg

Abnormal Uptake and causes:
Renal_obstruction.gif
Initial renal scintigraphy was performed to evaluate left renal function. Decreased blood flow with decreased function and minimal excretion is noted in the left kidney, suggesting an acute obstruction. (Stephanie Rhymer GU imaging part 1)

Artifacts:
Insert an image with an artifact, and explain what the artifact is.


References:
http://www.insideradiology.com.au/PDF/T43RNM-Renal-Scan-referrer.pdf

Shackett, Pete. Nuclear Medicine Technology: Procedures and Quick Reference. Philadelphia: Lippincott Williams & Wilkins, 2000. Print.

Stephanie Rhymer Power Point presentation- GU Imaging part 1

Ziessman, Harvey A., Janis P. O'Malley, and James H. Thrall. Nuclear Medicine: The Requisites. Philadelphia: Mosby Elsevier, 2006. Print.