Renal Nuclear Medicine Studies

Basic Renal Scan (Functional renal imaging)

Instrumentation

Data Acqusition

Energy peak: 140keV

Window: 20%

Dynamic/flow and static

Data analysis

Matrix:

Flow: 128x128

Dynamic: 256x256

Number of images:

Flow: 2sec/frame for 1-2min

Data set: 30-60 images

Dynamic: 30sec/frame for 30 min

Data set: 60 images

Static: 2min

Data set: 1

RPH

Tc99m-MAG3 or Tc99m-DTPA

Look at Rph section for dose amount MOA and MOL

Imaging:

Patient Position:
-Supine (can be standing for post void)
-Sternal notch to include both kidneys, inferior bladder in FOV

Views: Posterior (anterior if patient has had a renal transplant)

Procedure:

Bolus inj.

Immediately begin flow

Begin the dynamic function image after flow

Have the patient void then do the post void image standing with back to detector

Interpretation

Processing:

Renogram

A renogram is a time-activity curve that provides a graphic representation of the uptake and excretion of a rph.

Draw ROI around the aorta, bladder, both kidneys, and a background below each kidney

This creates the information to make the renogram

Normal: the curve for each kidney should be reasonably symmetric with prompt uptake and a peak between the first 3-5 min. A decreased slope of less than 50% at the 20 min mark.

If DTPA was used then a GFR of 120 mL/min is normal

If MAG3 was used then a ERPF of 600 mL/min is normal

Abnormal: more uptake in one kidney than the other. A lower excretion rate. Asymmetric curve

Indications

Evaluation of renal perfusion and function, and collecting system patency information

Equipment and Parameters

Full FOV for adults

Zoom FOV for pediatrics

Typically a zoom of 2

LEAP collimator

Single or Dual head gamma camera

IV Supplies

Patient Prep

Adequately hydrated

Oral hydration of 20 ounces (App. 3 cups an Hr. before imaging) or IV hydration of 250 ml prior to images

Start IV

Patient needs to void before scan and those who cannot void bladder need a urinary catheter

Detailed Patient History

Do you still have both of your kidneys?Previous transplant?Also look in patients records for:previous imaging done to see kidney location/sizecreatinine levels (high number may indicate kidney failure)If the patient has a nephrostomy, check the order to see if the tube should be clamped or not.Make sure patient has not had a recent renal arteriogram with contrast.

Contraindications

Pregnancy/Breastfeeding

A recent renal arteriogram with contrast

Currently taking Diuretics

Dehydrated

Patient is unable to remain still

Radiopharmaceuticals

Functional Radiopharmaceuticals

These are rapidly taken up and excreted by the kidneys by a single, simple physiological mechanism (i.e. ERPF or GFR)

Glomerular Agents

I-125 Iothalamate

Dose:Adult: 80 uCi Pediatric: 1uCi/kg; minimum 10 uCiAdministered via IVMOL: simple/passive diffusionAKA: GlofilMeasurement of GFRPoor image quality

Tc99m-DTPA

Dose:Adult: 10-20 mCiPediatric: 200uCi/kg; minimum 2mCiAdministered via IVMOL: Inulin analogExcreted 100% via glomerular filtration within 2 hrs.Assess renal blood flow, function, drainage of the pelvicalyceal systemsMeasures GFRReadily availableGreat image quality, low radiation dose to patient

Tubular Agents

I-131 Hippuran

Dose:Adult: .025-.2mCi Pediatrics: Not used in pediatricsAdministered via IVMOL: ion exchangeNo longer available in the US due to the high radiation dosage and low image qualityUsed to measure ERPFHigh first pass extraction: almost all of the radiation delivered to the kidneys remains in the kidneys.Near total tubal secretionHigh target to background ratio

Tc99m-MAG3

Dose: Adult: 10-20 mCi Pediatrics: 100 uCi/kg; minimum 1 mCiAdministered via IVMOL: binds to RBCClearance 100% via tubular secretionUsed to measure ERPFRecommended in pts with decreased renal function and infantsHigh first pass ratioHigh target to background ratioGreat image quality, low radiation dose

Morphological Radiopharmaceuticals
(AKA cortical agents)

Agents that are rapidly taken up by the kidneys, BUT use more complex mechanisms that involve ERPF, GFR, Tubular secretion, AND tubular resorption

Tc99m-glucoheptonate

No longer used in the US5-10% retention by the renal cortexDose: 10-15mCiROA: IVMOL: Glomerular filtration and tubular secretion

Tc99m- DMSA

AKA: SuccimerDose:Adult: 5mCi Pediatric: 55uCi/kg; minimum of 500 uCiAdministered via IV34% is retained by the renal cortexMOL: Tubular binding

Diuretic Renal Imaging

Indications

To distinguish between obstructive hydronephrosis and non-obstructive collecting system dilation

Evaluate renal function and urodynamics

Instrumentation

Data Acquisition

Dynamic/Flow and Static

Energy: 140 keV

Window: 20%

Data Analysis

Matrix

Flow: 128x128

Dynamic: 256x256

Number of Images

Flow: 2sec/frame for 2 min

Data set: 60 images

Dynamic: 30 sec/frame for 20 min

Data set: 40 images

Static: 2min

Data set: 1

Rph/Interventional pharmaceuticals

Tc99m-MAG3 or Tc99m-DTPA

Tc99m-MAG3 is the preferred RphGo to the descriptions of the Rph for dose, MOL, and MOA

Lasix: 40 mg

If a pediatric patient dose is 1mg/kg with a max of 40mg

Imaging

Views

Posterior with both kidneys and bladder within the FOV

If the patient has had a renal transplant than images should be acquired in the anterior view

Patient Position

Supine

Some protocols may want the patient to be in an upright position with there back to the camera. This is mostly for post void imaging.

Procedure

Bolus Injection of Rph

Immediately begin the flow imaging

Begin Dynamic imaging immediately after the flow. (20min)

Once the dynamic has been going for 20min, Inject the Lasix (40mg for an adult)

Some protocols have the patient void before the Lasix injection.The Lasix is a slow injection over a 1-2 min period

Continue dynamic for 20min

Have the patient void and then do a post void static. The patient can either be is the supine position or upright with there back to the detector.

Interpretation

Processing

Renogram

Normal: Symmetric curve, excretion begins 2-3 min post Lasix injections, and the bladder curve increases post Lasix injection.

Abnormal: Asymmetric curve, No excretion from the kidneys/ no filling of the bladder, and slow activity increase in kidneys

Additional Patient Prep

Stop taking diuretics 4 days prior to exam

Renal with ACE

Indications

To assess if patients hypertension is related to possible RAS (renal artery stenosis: the narrowing of one or more arteries that carry blood to your kidneys.)

Additional Patient Prep

NPO 4-6 Hrs before exam

Obtain a baseline BP and start an IV

Additional Contraindications

Patient was not NPO for at least 4 hrs

Stop taking ACE inhibitors/diuretics 4 days prior to exam

Instrumentation

Data acquisition

Energy:140 keV

Window: 20%

Data analysis

Matrix

Flow: 128x128

Dynamic: 256x256

Number of images

Flow: 2sec/frame for 2 min

Data set: 60 images

Dynamic: 30sec/frame for 20-30 min

Data set: 40-60 images

RPh/ Interventional pharmaceuticals

Rph: 5-10 mCi of Tc99m-DTPA or Tc99m-MAG3 (MAG3 is the preferred RPH)

Refer to Radiopharmaceutical section for MOA, and MOL

Interventional Pharmaceuticals

Captopril: 25-50 mg

Pill is crushed up and added to water Administered POMust be given 1HR prior to Rph injection

Enalaprilat: 40ug/kg

Administered via IVWait 10 min before the injection of Rph

Imaging

Procedure

Get the Baseline BP

Give the patient the chosen ACE inhibitor and wait the designated time

If captopril wait 1 hr. before Rph injection and take BP every 15 minIf Enalaprilat wait 10 min before Rph injection

Inject the chosen Rph and begin the flow immediatly (2min)

Begin the Dynamic immediately after flow (20-30min)

Take the patient final BP

Patient position: Supine

Views: Posterior with both kidneys and bladder in the FOV

Interpretation

Normal: Symmetric curve, prompt kidney uptake, Decreased kidney activity to T1/2 at 8-12min mark, bladder activity increases as the kidneys excrete

Abnormal: Asymmetric curve, low uptake, little to no excretion from kidneys, bladder activity does not increase

Processing: Renogram

Optional Maneuvers

A baseline renal scintigraphy without ACE should be done either before the Scintigraphy with ACE, or it can be done 2-3 days post Ace renal scintigraphy

Some protocols give the patient lasix just like a diuretic scintigraphy to empty any pelvic retention

Morphological Renal Imaging

Indications

Adema or scarring from acute pyelonephritis

Confirmation of suspected hypertrophic column of berlin

Instrumentation

Data Acquisition

Energy: 140keV

Window: 20%

Data analysis

Matrix: 128x128

Number of images

Statics

Parallel hole colimator: 500K counts per image

Data set:2-6 images

Pinhole Collimator: 100K counts per image

Data set:2-6 images

SPECT: 180 Rotation with 40sec/stop for 40 Views

Rph

Tc99m- DMSA or Tc99m- GH

Go to Radiopharmaceutical section for Dose, MOL, and ROA

Imaging

Position: Supine

Views: Ant, Post, and an optional RAO,LAO,RPO,LPO

Procedure

Inject the Chosen Rph, then wait 2hrs before imaging

Select the proper collimator

Parallel or Pinhole CollimatorA Pinhole collimator is preferred for children

Place the patient supine and begin taking static images (approximately 3min per view)

A SPECT can also be done (Approximately 15-30min)

Interpretation

Normal: A smooth renal contour. Uniform and equal tracer concentration

Abnormal: To differentiate a Column of Bertin from a true mass, DMSA will show uptake and a mass will not have any uptake. If Acute Pyelonephritis is the issue it may appear as single or multiple defects resulting in decreased uptake.

Processing: No processing, it is a qualitative study

Additional Patient Prep: If this is a pediatric patient, a parent must sign a informed consent for sedation to begin study

Vesicoureteral Reflux Scan

Indications: Evaluation and detection of vesicoureteral reflux (VUR)

Patient Prep.

Place absorbent pads around the potty chair if it is going to be used

Thoroughly explain the procedure to both the patient and the parents

Obtain a written consent for catheterization

Have the patient void before the exam. If the patient is an infant, have them wear a clean diaper.

Prepare a 500mL bag of saline

Instrumentation

Data Acquisition

Energy: 140keV

Window: 20%

Data Analysis

Matrix: 128x128

Number of Images

Bladder filling: Dynamic 5sec per frame for 60 sec.

Data Set: 12 images

Pre-Void: 120sec static image

Data Set: 1 image

Void: Dynamic 2sec/ frame for 120sec.

Data Set: 60 images

Post-Void: 120sec static image

Data Set: 1 image

Ancillary Equipment: IV pole and potty seat (if needed)

Rph

Tc99m- Sulfur Colloid

Dose: .5-1mCi

Route of Administration: Via Foley catheter tubing

MOL: Compartmental localization with the flow of Urine

Imaging

Patient Position: Sitting if using the potty seat, or lying supine of the table

Views: Posterior, LPO, and RPO with bladder and kidneys on the FOV

Procedure

Prep the patient by having them void or by making sure they are in a clean diaper if an infant.

Prep 500mL saline bag and the Tc99m sulfur colloid

Place the foley catheter using aseptic technique. Inflate the balloon and tape to secure.

Prepare camera for dynamic 60sec fill. Then inject Tc99m sulfur colloid into the tubing connected to bladder catheter. Begin to fill bladder with saline and begin the dynamic image.

Fill the bladder until drip from the bag slows or the patient begins to void around the catheter.

To determine the max capacity of a patients bladder use the formula: (age+2) x 30= Volume instill (mL)

If Reflux is seen, record the amount of saline that was infused

Take a immediate static once the bladder is full (120sec)

Deflate the catheter balloon and have the patient void while taking a dynamic image (2sec/frame for 120sec)

Take an immediate post-void static (120 sec)

Remove the patients foley catheter. Then measure the urine.

Interpretation

Normal: No reflux visualized. Nearly all of solution is voided from bladder.

Abnormal: Activity in upper urinary tract during filling, at full capacity, and /or while voiding.

Processing

Calculate the residual urine volume

Formula for calculating the residual volume (mL)= Voided volume (mL) x Residual counts/min ________________________________________________ Max counts/min - Residual counts/min

Draw ROIs around intrarenal collecting systems and bladder