diuretic renal scintigraphy

4_5888477601076350746

by محاضرات غير ربحية للطلاب

Image acquition

by Kabita Baral

Renal Failure

by Loralie Rodrigues

Rhabdomyolysis with Crush Injury

by Yerin Han

injection into a foley catheter by injection port

cystography

bladder

Activity in upper urinary tracts during filling, full capcity, and while voiding

No reflux visualized

All or almost all of solution is voided from the bladder

interpertation

total bladder volume of residual post void volume and bladder volume at initiation of reflux can be measured

residual volume- (voided volume)(post void ct)/prevoid ct -post void ct

total volume - voided volume+ residual volume

reflux volume-ROI cts x totalbladder vol/prevoid bladder ROI ct

initial volume- total volume - total saline instilled

bladder volume at reflux- initial volume + saline reflux volume

procedure

45 min

hang 250-500 mL saline bag (make sure tubing is clamped) for gravity feed infusion (no higher than 100 cm above table) note amount of saline at start and finish volume going to need tone instilled

(age+2)x30

filling phase

start camera for flow, fill bladder completely with Rph/ saline mixture. monitor P-scope closely for signs of reflux. if reflux is seen, record amount of saline infused at that time. when bladder is full, stop flow images and take 120 sec immediate static of POST and Lt and Rt POST obliques. record amount of saline used to fill bladder and cpm during POST view instruct pt to resist the urge to urinate.

voiding phase

start flow study. deflate folley balloon have pt void take a 120 sec immediate post void POST static and record CPM. measure and determine volume in mL voided by pt

review images for any reflux

sitting up and pelvis against camera bladder and bag FOV some kidneys

Tc99m SC

agitate before injecting-particles can settle to the bottom or on the sides of the syringe

Tc99m DTPA

0.5-1 mCi

kit prep

shake and shoot

LFOV gamma camera LEAP or LEHR collimator 64x64

filling phase 10 sec/frame for 1 min 64x64

pre void phase 120 sec static image

voiding 2 sec/frame for 120 sec

post void phase 120 sec static image

pregnancy/breastfeeding

before you bring patient back cover all equipment with chucks

keep additional chucks on hand

ID patient

verify DO

explain procedure

consent for catherzation

void prior to starting scan

use a clean weighed diaper for infant

note amount of saline start to finish

indications/symptoms

Evaluation and detection of vesicoureteral reflux - VUR

diahrea

lack of appittie

fever

strong family history

direct - scan using a catheter, is preferred it has a higher sensitivity and specificity than the indirect method

indirect- scan without using scan

morphological renal imaging

critical organ

kidney/bladder wall

abnormal

pyelonephritis is reconized by the decrease of uptake

uptake in a column of bertin but not in a mass caused by a tumor

normal

homogeneous uptake in both kidneys

should demonstrate a smooth renal contour

shape of kidneys vary, as is the thickness of the cortex

upper poles may often appear less intense due to splenic impression on the cortex and attenuation from liver and spleen

Tc99m GH

adult 10-20 mCi children 200 uCi/kg

MOL-secreted by glomerular filtration and tubular secretion

kit needs to be refrigerated

renal clearance is 50% at 3 hours

Tc99m DMSA *perferred

adult 5 mCi children 50uCi/kg

websters rule for pediatric dose; (age+1)/(age+7)x adult dose

MOL- tubluar binding , it is taken up by the renal cortex (proximal convoluted tubule)

90% is bound to plasma protein after injection

approximatly 16% of DMSA will be in urine 3 hours after injection

data acqusition

timing- 2 hours after dosing

statics - 500K cts each image for a total of 5 images.

views- POST/RAO/LAO/RPO/LPO with kidneys in the center of FOV

SPECT- 180 degrees- 40 views per head 3 degrees/stop or 40 sec/stop

LFOV gamma camera

parallel hole collimator for differential calculation

pinhole collimator for for cortical images

SPECT single, dual, or triple head

pregnancy or breast feeding

dehydrated

well hydrated two 8 oz. of water

informed consent- for children sedation my be ideal

detection of pyelonephritis

used to detect the presence or absence of small renal infarctions

Adema or scarring from acute pyelonephritis

hypertrophied columns of Bertin are not uncommon and can mimic a renal mass lesion, thus it is important to detect it because it alleviates biopsy and radical surgery.

confirmation of suspected hypertrophied column or Bertin

renal wit6h ACE inhibition renogram

optional manuver

some protocols use IV furosemide shortly afterRph to clear the renal collecting systems of activty, which can interfere with cortical indices.

adults- 0.3-0.5 mg/kg

Subtopic

decrease in renal uptake

high blood pressure-hypertension is renin dependent.

prolongation of renal parenchymal transit

normal blood pressure

systolic- 90-140mmHg

diastolic 60-90mmHg

final blood pressure reading should be obtained at end of study

ACE inhibitors

Enalaprilat

orthostatic hypertension

0.04 mg/kg in 10 mL saline, IV over 5 min

timing- 10 min wait time after injection

Captopril

adverse effects

orthostatic hypertesion

rash

chest pain

tachycardia

loss of taste

25-50 mg pill

your going to crush pill, then put in water and give to patient.

timing- give Rph 60 min after patient was given captopril

monitor blood pressure every 15 min once given

flow- 2 sec/frame for 1 min 128x 128

contraindcation

patient dehydrated

not NPO 4-6 hours prior

patient not off ACE inhibitors/diuretics/A2 blockers 4 days prior

pregnant or breastfeeding

not NPO 48 hrs captopril

not NPO 1 week for lisinopril or enalaprilat

hydrate 1 hour prior 10 mL/kg

NPO 4-6 hours prior

4 days prior stop diuretics/ACE inhibitors/ A2 blockers

obatin a baseline blood pressure and start IV

NPO 48 hrs for captoptil

NPO 1 week for lisinopril or enalaprilat

indication

SNM procedure guidlines

renovascular hypertension

abrupt onset or severe hypertension

abdominal or flank bruits

unexplained azotemia in elderly hypertensive patient

recurrent pulmonary edema in an elderly hypertensive patient

hypertension in infants with an umbilical artery catheter

importance of this study

sensitive non-invasive

used for diagnosing renalvascular hypertension 1-4% of all cases of hypertension.

blocks A1 to A2

organ receiving largest dose of radiation

diuretic

calculate the ERPF

you should start to see the diuretic take in effect within first min

1/2 T clearnace should be by 10 min

the diuretic will be part of the graph

1/2 T clearance longer then 20 mins

urodynamically significant outflow obstruction is present

asymmetrical excretion

1/2T clearnce of less then 10 min

rapid and almost complete washout of radio tracer

both kidneys should excrete symmetrically

radiopharmaceutical

diuretic lasix(furosemide)

storing

room temp

keep out of light

drug interactions

furosemide may increase the ototoxic potential of aminoglycoside antibiotics

in pateints with anuria

patients with anhistory of hypersensitivity to furosemide

adveres effects

nausea

vomiting

diarrhea

headache

dizziness

hypotension

adult 0.3-0.5 mg/kg given over 2 to 3 min or based on creatinine levels children 1 mg/kg with max 40 mg

timing

F+0

F+20

F-15

Tc99m DTPA or MAG3

adults 10-15 mCi. children 100 uCi/kg max 5 mCi

iv bolus

LFOV gamma camera LEAP or LEHR collimator

flow 20 sec/frame for 1 to 2 min 128x128

dynamic 20-30 sec/frame for 20 min 256x 256

post void static 500k

energy 140 keV window 20%

contraindcations

recent NM study

pregancy or breast feeding

dehydration, diuretics

well hydrated-IV hydration is more relaible in the diagnosis of questionable cases of urinary obstruction

catheter for children/infants-in some cases the diagnosis of obstruction may be more reliable with bladder catheter

obtain serum creatinine levels

void prior

review patients hostory of urinary tract obstruction, prior surgery to the urinary tract and congenital abnormaities are important for accurate interpretaton of the study.

withhold diuretics for 24 hrs prior

indications

evaluation of dilated renal collecting system vs. obstructed renal collecting system

prenatal ultrasound diagnosis of hydronephrosis

post-surgical evaluation of a previously obstructed system.

distension of pelvicalyceal system as an etiology of back pain.

Renal scintigraphy

artifacts

phantom kidney-spleen overlies the left kidney giving a false impression of asymmetrically increased renal perfusion in patients with prior left nephrectomy

horseshoe kidney- a congenital abnormality where the bottom of the kidneys are connected.

attenuation

patient movement

foreshortening-planar artifact where kidney appears smaller then actual size

organ recieving largest dose of radiation

bladder wall

optional maneuvers

renal transplant

renal with ACE inhibitors- captopril oral 25-50mg should be taken hour prior to study or enalaprilat 0.04mg/kg IV should be given 10-15 prior study.

renal with lasix

processing

"a rengoram is simply a time activity curve that provides a graphic representation of the uptake and excretion of the Rph by the kidneys".

3 phases

3. clearance or excretion phase- represents the down slope of the curve and is produced by excretion of the Rph from the kidney and clearance from collecting system.

2. tubular concentration phase- first 1-5 mins and contains the peak of the curve. The inital uptake slope closely correlates with the ERPF vaules.

1. vascular transit phase- first 30-60 sec and represents blood flow of the Rph in each kidney. Should be symmetric . It should exceed or be equal that of the aorta .

ROIs are drawn over the aorta- may be used to asses the discreteness and adequacy of the injected bolus as well as relative renal perfusion.

ROIs are drawn around the kidneys - renogram curves are generated by these ROIs. occasionally just draw around the renal cortex if a considerable amount of collecting system is oresent.

background subtractions ROIs- are selected just inferior to each kidney.

ROIs around bladder

abnormal study

anything 40% or below

difference between kidneys 20% or more

delay in transit of Rph in kidneys

asymmetrical

normal study

renal uptake @ 2-3 min

1/2 T excretion 8-12 min

activity 50% by 20 min

max activity by 3-5 min

symmetrical

imaging technique

views- POST

patient supine with kidneys and bladder in FOV

transplant patients

they should be supine with ANT view images

radiopharmaceuticals

Tc99m DTPA or MAG3 which is perferred

10-15 mCi

IV bolus

MOL DTPA glomarular filtration MOL MAG3 tubluar secretion

kit prep for MAG3-vent with a needle to remove some nitrogen, add 20-100 mCi in 2 mL to vial, heat NOT boil for 10 min, cool for 15 min. Remove some pressure from vial then add 3 more mL for a total of 5cc. the tag needs to be 90% or better for it to be usable.

when looking for ERPF we use MAG3 normal ERPF is 600 ml/min

kit prep for DTPA- is very simply shake and shoot is all you need to do.

when looking for GFR we use DTPA normal GFR rate is 120ml/min

data acquisition and analysis

flow- 2 sec/frame for total 30 frames 128x 128

dynamic- 20 sec/frame for total 20 min 256x256

post void static 500k cts

static of dose before and after injection 30 cm from collimator is done at some clinical settings

energy 140 keV window 20% timing is immediatrly after dosing

detector system

LFOV Gamma Camera. LEAP collimator, for pediatrics diverging collimator may be optimal.

contraindications

dehydration

recent nuclear medicine study.

pregnant or breastfeeding.

patient prep

Encourage patient to void prior to scan and after

if not an abnormal renogram curve demonstrating delayed peak activity, delayed Rph clearance or an elevation of the ecretion slope can result.

patient should be well hydrated 1 hour before study 2 to 3 8 oz. cups of water over 30 min.

Indications

evaluation of renal perfusion and function and collecting system patency information.

relative renal function- both kidneys should function relatively the same.

renal transplant evaluation- is for checking that the transplant is not leaking urine,renal infarction, rejection obstruction, or cyclosporine toxicity.

acute renal failure-- helps determine their prognosis and most helpful in excluding acute vascular obstruction as a cause of renal failure.

obstructive uropathy-evauate obstruction in ureters

renovascular hypertension- evaluate renin hormone which is located in the kidneys that effects high blood pressure.

infection or inflammation-can be caused by bacteria. UTI is most common infection can escalate to a kidney infection. 85% is causative organsim is eschrichia coli

vesicoureteral reflux-evaluates the possibility of back flow of urine up the ureters.