Renal Imaging

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Renal Imaging

View & Position

Supine

Posterior

Unless the study is post transplant, then an anterior view is acquired.

Scans

Cystogram

Used to visualize the bladder

F.O.V.

• Have bladder and bag in F.O.V.
• Dome of bladder in bottom of F.O.V.
• Kidneys in the upper F.O.V. (not necessary to have full kidneys in view

45 min study

3 phases:

• Bladder full
• Urination phase (Micturition)
• After voiding

Preparation

• Need to have a foley catheter
• Cover all surfaces with chucks
• Prep saline bag (250-500 mL) Inject radiopharmaceutical into bag

Flow

Filling Phase: 10 sec/frame- 60 seconds

Start imaging

• Filling phased: start image for flow
• Fill bladder completely with saline/radiopharm mix through foley port (calculated by-- Age of patient x 30 =

bladder capacity)

• Fill bladder till drip slows or leakage of port

Watching for reflux above the bladder.

If there is reflux:

• Record saline infused at that time.

Pre-Void Phase

Pre-Void Phase: 120 second static image

Full Bladder:

• Stop flow images and immediately start static image of Posterior of patient.
• (If possible) Right & left obliques
• Record the amount of saline used to fill and CPM

Have patient hold bladder!

Void Phase

Voiding phase: 2 sec/frame 120 sec

Start 2nd "flow" study:

• Deflate foley Cath.
• sit patient up and use potty chair
• Have patient urinate
• Visualize urination

Post-Void Phase

Post Void Phase: 120 sec static image

• Record Cpm
• Measure and record volume in mL of voided fluid
• Calculate Saline- volume urinated
• Review for signs of reflux

• Activity in upper urinary tracks seen during filling, pre ,and during voiding

• No visualization of reflux of tracer past bladder during filling or voiding.
• All or most solution is voided from bladder

1 mCI

TC99m DTPA

Tc99m- Diethylenetriamine Penaacetic Acid

Tc99m Sulfur Colloid

Significant renal dysfunction

Evaluate and detect VUR

Vesicoureteral Reflux- failure of the Uretervesical valve.

Morphological Scan

Renal Cortical Scintigraphy

Peds Dose: 50 uCi/kg

Tc99m GH

Tc99m- Glucoheptonate

15-20 mCi

Tc99m DMSA

• Tc99m Dimercaptosuccinic acid
• Preferred radiopharmaceutical due to 40% retained in tubules.

5 mCi

Inject radiopharmaceutical

via IV

Wait 2 hours to image

Images

• SPECT 180
• Planar 500k counts, ANT/ POST
• (optional) Pinhole(look at each kidney individually

• Decreased uptake: possible mass
• Decreased uptake in renal paranchyma - Pyelonephritis

• Uptake will be seen in the Column of Bertin.
• homogenous uptake

Contraindications: None

presence or absence of renal infarctions

Differentiate between mass and normal variant

Normal variant is the Column of Bertin

Detect Pyelonephritis

Pyelonephritis:Kidney infection that starts in the bladder and travels to kidneys. This is due to reflux of bacterial infected urine.

Renal Scan With ACE Inhibitor

Renal Scintigraphy Augmented by ACE inhibitor

ACE inhibitor Administration

• Captopril - 50mg pill (Oral) - 1 hour prior to radiopharmaceutical
• Enalaprilat - 40ug/kg (IV) over 3-5 min. - 10 min prior to radiopharmaceutical

Injection of RadiopharmaceuticalImage Immediately

IV Bolus

Functional renal scan procedure

Renogram

This establishes a Time-activity curve, representing perfusion and function of the kidneys.

If test proves abnormal- acquire baseline test (with no ACE inhibitor) 3-4 days post.

Normal results: No significant abnormalities in the time-activity curve

Non-Radiophamecutical

Enalaprilat

40ug/kg

IV administration given over 3-5 minutes

monitor blood pressure prior and after administration

Captopril

25-50 mg

• Oral administration

monitor blood pressure every 15 minutes for 1 hour post administration

Patient currently on ACE inhibitor

Patient needs to discontinue ACE inhibitor

• Captopril- 48 hours prior to scan
• Lisinophil or Enalaprilat- 1 week prior to scan

RAS wit Hypertension

Renal Hypertension & no RAS

RAS: Renal Artery Stenosis

Diuretic Renal Scan

Non-Radiopharmaceutical

Furosemide

Doses:

• Adult: 40 mg
• Peds: 1mg/kg max 40 mg

Bolus Injection Image Immediately

ROI:

• Sternal notch in top 1/3
• kidneys center of view.
• Bladder at bottom 1/3

Dynamic acquisition "Function"

• Represents the function of the kidneys.
• Dynamic acquisition for 20-30 min. 20sec/frame.
• Can be used to determine both absolute and relative renal function.

Inject Furosemide

• Inject Furosemide (Lasix) at the 20-30 minute mark. This is very important as timing is crucial to this study
• Dose: Adult- 40 mg Peds- 1mg/kg max 40 mg
• Inject Furosemide over 2-3 minutes
• Have patient hold bladder

Lasix response- 2-5 min

max- 15 min.

Dynamic acquisition #2

Continue Dynamic acquisition for another 20-30 min.

20 sec/frame

(Optiona) Post void

Renogram

Abnormal

Normal

Functional Rph:

Tc99m- Diethylenetriamine Penaacetic Acid

MAGS3

GOLD STANDARD

Functionl Rph:

Tc99m- Mercaptoacetylglycylglycylglycine

10 mCi

UTI

Function

• Evaluate function & post-diuresis drainage

Functional Renal Scan

Patient on diuretic

Patient on ACE inhibitor

Indications

Renal Artery Stenosis

Hydronephrosis

Occurs in infants

Renal Function

Renal function and Urodynamics

Split renal function

Renal perfusion

Urinary Reflux & Scarring

Acute Renal Failure

Renal Transplant

Post transplant evaluation of function

Procedure

Bolus Injection Image immediately

ROI:

• Sternal notch in top 1/3
• kidneys center of view.
• Bladder at bottom 1/3

Blood flow & filtration

Dynamic acquisition. 20 frames at 3sec/frame- 1 min.

Represents the the initial arrival of Rph into the kidneys.

Lasts 30-60 seconds.

Dynamic Aquistion "Function"

• Represents the function of the kidneys.
• Dynamic acquisition for 19-30 min. 20sec/frame.
• Can be used to determine both absolute and relative renal function.

(Optional)Post Void

Static acquisition for 2 min. after patient has voided.

Position: Supine or sitting

Processing

Renogram

This establishes a Time-activity curve, representing perfusion and function of the kidneys.

The curve:

1) Vascular Transit Phase: perfusion of kidneys and aorta.

2) Tubular Concentration Phase: the peak of the curve. correlates with ERPF.

3) Excretion Phase: Down slope of the curve, produced by excretion of Rph and clearance of collecting system.

Abnormal Study

Any deviation from the "normal" activity curve.

Less than 600mL/min

Normal Study

Assessing ERPF- Normal is 600mL/min

Max activity: 3-5 min

Renal uptake ratios: 2-3 min

1/2 Time excretion: 8-12 min

Radiopharmaceutical

DTPA

Functional Rph:

Tc99m- Diethylenetriamine Penaacetic Acid

• Glomerular filtration agent
• No tubular excretion

Dose:10-20mCi

Pediatric Dose: 200 uCi/kg; Min. 2 mCi

MAG3

GOLD STANDARD

Functionl Rph:

Tc99m- Mercaptoacetylglycylglycylglycine

• Tubular secretion
• Effective renal plasma flow agent

Dose: 10-20mCi

Pediatric Dose: 100 uCi/kg; Min. 1mCi

Patient Prep

Void prior to study

NPO not needed

Light meal and hydration before scan are okay.

Patient MUST be hydrated

This can be done by drinking fluids- at least 20 ounces, or can be done by IV hydration- 250mL

IV must be in place

Equipment

Single or dual head gamma camera

LEAP or LEHR collimator

LFOV

Contraindications

Dehydration

Recent NM studies performed

Pregnant/Breastfeeding

Iodine contrast study performed recently