ZMDA MRD450 Intravenous Urography. Introduction Terminology Patient preparation Contrast Scout films...

ZMDA MRD450

Intravenous Urography

Intravenous Urography Introduction Terminology Patient preparation Contrast Scout films Compression Tomography Routine procedure/filming sequence

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Intravenous Urography Aka excretory urography Use decreased significantly in recent years

CT, US, MR is replacing

Remains primary modality for visualization of pelvocalyceal system and ureter


ZMDA MRD450

Terminology

Terminology Urogram

Visualization of kidney parenchyma, calyces and pelvis resulting from IV injection of contrast

Pyelogram Describes retrograde studies visualizing only

the collecting system

So, IVP is misnomer, should be IVU


Cystography Describes visualization of

the bladder Urethrography

Visualization of urethra Cystourethrography

Combined study to visualize bladder and urethra


One more word about terminology….

Contrast is what we give intravenously Dye is used on clothes and in cooking to

change the color of things—it is not given IV to patients!


Preparation of patients for IVU Bowel Prep

Controversial Eliminates fecal material and reduces amount of gas in

bowel

Dehydration Now thought to be unnecessary Improves degree of opacification of contrast Patients now kept NPO to decrease chance of vomiting as

well as producing slight dehydration


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ContrastWill be covered later

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Scout Films

Scout films for IVU Evaluate technique Look for calcifications Abnormal soft tissue Air within urinary tract Bony abnormalities Determine if a contraindication to abdominal

compression exists


Abnormal Soft Tissue Renal outlines Spleen Liver Loss of psoas margin may indicate

retroperitoneal pathology


Air Within urinary tract may indicate fistula or

gas forming infections If patient has Foley, may have been

introduced thru Foley


Bony abnormalities Osteoblastic metastases due to prostate

cancer Spine abnormalities may be associated

with neurogenic bladder


Proper scout radiograph Supine Should extend from upper renal poles to 2

cm below the inferior margin of pubic symphysis

Often difficult to fit this large area on a single radiograph, may need…. 14 x 17 of abdomen 10 x 12 of lower pelvis


Proper scout


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Ureteral Compression films

Value of ureteral compression Normal peristalsis may leave portions of

ureters empty of contrast With compression, ureters are compressed

against pelvis and are temporarily obstructed

As a result, the proximal ureters and intrarenal collecting system are optimally distended


Contraindications to compression

Abdominal Aortic Aneurysm Ureteral obstruction

Acute abdominal/flank pain

Recent abdominal surgery Abdominal stomas

Colostomy, ileostomy, ileal conduit


Proper compression Ureters are compressed against pelvis Place belt and pneumatic balloons at

upper edge anterior superior iliac spine Paddles should nearly meet at the

midline


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Tomograms

Scout tomograms


Tabletop is 0 cm position

Estimated midcoronal kidney level is determined as…

( Distance in cm from table top to ant abd wall / 3) +1

Example

27/3 = 9

9+1 =10cm

Anterior abd is 27 cm


Tomograms Average patient-- tomos at

8, 9, 10 cm Heavier patients– tomos at

9, 10, 11 Thinner patients– tomos at

7, 8, 9


Remember upper pole of kidney is more posterior than lower pole Think about kidney lying on

psoas muscle that gets larger more inferiorly so in average patient Upper pole best seen at 8 cm from

table top Mid kidney best seen at 9 cm from

table top Lower pole best seen at 10 cm from

table top


Tomograms May not need tomos

If study is a repeat of a study from short time ago when kidneys have been evaluated by other

modality and were shown to be normal


Value of tomograms with barium on scout


Value of tomograms to get rid of overlying bowel gas


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Routine procedure/ filming sequence

General principles of IVU No universally accepted filming sequence Best examination is monitored by radiologist and

modified to answer clinical question However, certain views are essential to every

examination Scout Film Early Nephrogram films Excretion films


Example Preliminary scout (patient should void before study) Inject contrast Immediate tomograms at 2,3,4 minutes

10 x 12 over kidneys 5 minute film 14 x 17 Inflate compression paddles 10 minute supine film with compression 15 minute film (14 x 17) immediately after release of

compression Bladder image

Optional—delayed, oblique, prone or post-void


Additional views Oblique Views

Good for questionable ureteral lesions For differentiating extrinsic and intrinsic renal and

ureteral masses Visualization of posterolateral aspect of bladder


Value of oblique views to move ureter from spine


Delayed Views 1 hour to 48 hours- in cases of obstruction Better to CT patient for immediate diagnosis


Additional views Remember that contrast opacified urine is

heavier than nonopacified urine, so use gravity…

Prone film Helps fill ureteral areas not seen in supine position

since upper ureters more anterior than kidney


Erect film

Promotes emptying of collecting system Optimal for showing bladder hernias Shows layering of calculi in cysts Demarcates areas of ureteral obstruction better than

prone views


Example of prone view in patient whose left ureter was not filling on supine views


Postvoiding films

To determine residual urine in bladder—especially in older male patients

To look for bladder neoplasms Must be obtained immediately after voiding


Transitional cell carcinoma


Images from Normal IVU Studies…


1,3,5 minute tomo images

1 min. 3 min

5 min


Examples of compression images

10 min with compression

15 min without compression


Film with compression immediately after release of compression


Value of fluoroscopy


Normal Bladder, pre and post-void


ZMDA MRD450

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ZMDA MRD450 Intravenous Urography. Introduction Terminology Patient preparation Contrast Scout films...

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