Intravenous Urography

INTRAVENOUS UROGRAPHY

IVU CONTENT

DEFINITION/INTRODUCTION

• ANATOMY Of THE URINARY SYSTEM

INDICATION

CONTRAINDICATIONS

PREPARATIONS

EQUIPMENT USED

PROCEDURE /TECHNIQUE+CONT MEDIA

RADIOLOGICAL ANATOMY

COMMON PATHOLOGY RELATED IN IVU EXAM

ADVERSE EFFECTS

OTHER IMAGING MODALITIES

INTRODUCTION

INTRAVENOUS UROGRAPHY(IVU)/IVP/EU

Refers to radiological examination of the urinary tract(kidneys, ureters and urinary bladder)following injection of the contrast medium via vein (of the arm) and excreted by the kidney as urine.

is indicated in suspected urinary tract pathology when ultrasound has failed to make a diagnosis

Kidney s

Are paired organs approximately 8-13 cm in lengh,2-3 cm in AP diameter and 4-5cm in width .

• Lie obliquely in the retroperitoneal cavity

Have concave media border that houses the hilum Left kidney is typically larger than the right kidney is positioned lower because of the size of the liver (1-2 higher) Kidneys moves approximately 2 cm with respiration

Renal structure

The layers of tissue that enclose the kidney are gerottas fascia(outer),per nephric fat(middle),true fibrous renal capsule (inner) Parenchyma of the kidney contain the cortex and medulla Cortex contains the renal corpuscles and glomeruli Medulla is the inner portion of the kidney adjacent to the calyces contains loop of henle ,renal pyramids and collecting tubules

Blood supply

Renal veins, arteries ureters and lymph vessels enter and leave the kidneys at renal hilum The main renal arteries branch off the aorta Once in the renal pelvic,a renal artery becomes segmental artery segmental artery continues branch into the inter lobar arteries ,inter lobar arteries eventually become the arcuate arteries Renal veins drains the kidneys and empty into ivc

Ureters and urinary bladder

• Two muscular tubes, 25 cm long that extend from the pelvis to the bladder
• Propel urine from the ureters to the bladder
• Narrowing's of the ureters
• At the beginning ( renal pelvis)
• At the pelvic brim, (crossing common iliac)

At the end where it enters the bladder

Blood supply of the ureters

• Upper part: renal artery
• Middle part: ovarian/ testicular artery

Lower part: superior vesicle artery branch of internal iliac artery

Urinary bladder

• Bladder: lies behind the pubic bones

Apex lies behind symphysis pubis

Base is posterior and is related to the vagina and uterus in females and rectum and sigmoid in males Superior surface is above and related to uterus in females and sigmoid colon in males Infero lateral surfaces related to pubic bones.

Neck lies on prostate in males, and urogenital diaphragm in females.

Blood supply u bladder

Blood supply: superior and inferior vesicle arteries from internal iliac

INDICATION

• Check for normal function of the kidneys
• Hematuria
• Suspected renal calculi
• Check the course of the ureters
• Check for anatomical variants or congenital anomalies (e.g.horse-shoe kidney
• Persistent pyuria

renal colic with a normal scan

suspected renal disease that is likely to cause calyceal deformity such as tuberculosis, papillary necrosis and chronic pyelonephritis

Contraindications

• Advanced renal failure – use ultrasound
• Polycystic renal disease – better seen on ultrasound
• Vague abdominal pain
• Acute urinary tract infection
• Not diagnostic for renal artery stenosis
• Patients with history of reaction to water-soluble contrast media

Pregnancy

Preparations of the patient

This is of a great importance the aim is to rid the bowel of all fecal material without producing gas shadows By giving purgatives drugs like bisacodyl or castor oil before examination perfomed Low residual diet during previous day,it is an advantage to stop all food and drink for 12 hours Some times enema as high colonic wash out should be used.

Checking serum cretinine/blood urea

If the blood urea is more than a little elevated, IVP will seldom be of value, , especially if standard amount of contrast is used If an IVP is considered to be necessary an increased amount of contrast should be used If urea is very high IVP will not be diagnostic and may be harmful Main is to check physiological function of the kidney

Equipment used

• 2 or 3cc Syringes
• Cotton swabs (2-3)
• 4 x 4cm Gauze pads
• Cannulae – varying sizes & designs
• Sterile gloves
• Cassete of varying in size
• Emergence drugs ie hydrocortisone and adrenaline

Contrast medium of choice

Procedure /technique + contrast medium

Intravenous urography involves an intravenous injection of a water soluble iodinated contrast agent.

These agents are classed as IONIC (HIGH OSMOLAR) and NON- IONIC (LOW OSMOLAR).

The non- ionic contrast agents are safer to use and cause less severe reactions than those encountered with the cheaper ionic agents.

These are iopamidol,iopromide(ultra visit),hypaque,urovsion,or conray

Intravenous Urography

As there is a risk of producing a severe reaction even with non- ionic contrast, an IVP should only be performed if there is a valid clinical indication The standard dose of contrast for an adult is 50cc but this can be increased to 100cc in very large patients or patients with an elevated blood urea.

In children a guide to dosage is 1ml per kg of body weight up to age 15yrs There should always be adrenaline & hydrocortisone immediately available in case of a severe reaction.

procedure

A plain film is always taken before injection of the contrast medium.

This is because calculi are masked by the contrast and would not be seen once the kidneys have started to excrete it.

This film should be carefully checked for any opacity, which may be lying in the renal tract.

it also help in looking for the exposure factor and it is known as kub.

Injection of a contrast media

After the preliminary film have been viewed and properly studied ,contrast medium is then injected into a vein(ussualy median cubital vein of the arm because flow is retarded in the cephalic vein as it pierces the clavipectoral fascial.

The contrast medium is injected slowly intravenously, during injection of the contrast medium the radiographer/radiologist should talk with the patient

Timing after injection

0 minute

This is taken immediately after contrast injection and is called nephrogram shows renal parenchyma opacified by contrast in the renal tubules)

5 MINUTE FILM(AP-RENAL AREAS

This film is taken to determine if excretion is symmetrical and is valuable for assessing the need to modify technique, e.g. further injection of contrast medium if there has been poor initial opacification.

Compression may be applied in some centers at this point to distend the pelvicalyceal systems to demonstrate any filling defects and a film taken at 10 minutes of the renal areas.

15 MINUTES FILM

There is usually adequate distension of the pelvicalyceal system and ureters with opaque urine by this time. compression is released when satisfactory demonstration of the pelvicalycealsystem has been achieved The 10-15film is usually a full-length film to show early ureteric filling before the lower ureters become obscured by contrast in the bladder. At this stage the calyces, renal pelvis and parts of the ureters are outlined with contrast. This is called the pyelogram phase. The calyces may be different on the two sides as there is considerable variation anatomically but they should be reasonably symmetrical and the kidneys excreting at the same rate with equal fading of the nephrogram

30 MINUTES

A.TAKING AT THE AREA OF THE KIDNEYS

B.FOR KUB

C.BLADDER VIEW

After taking series of radiograph the tell the patient go and micturate in the toilet

POST MICTURATION

• In this film
• Drainage of upper tracts is assessed.
• Bladder pathology may be seen better on this film.

Post micturition residue is assessed

Additional films

Prone abdomen -may provide better visualization of the ureters by making them more dependent.

Delayed films -may be necessary for up to 24 h after injection in cases of obstructive uropathy

Radiographic anatomy

Adverse reaction of the contrast media

Contrst media is adverse reaction categorised from mild,modere to severe ..

Severe reactions are rare but dangerous, requiring immediate treatment. For this reason intravenous pyelography should not be performed unless medical assistance immediately available.

• Most reactions are mild and usually do not require any treatment.
• Most contrast reactions are Urticaria
• Laryngeal oedema
• bronchospasm
• Vascular collapse

Cardiac Arrest

AFTER CARE OF THE PATIENT

• General psychological reassurance.

Needle wound site dressed and checked for extravasation.

Administer necessary drugs if patient reacts to CM and let patient rest for a while as you monitor them.

• Advise pt to take plenty of fluids to help in flushing out CM from body
• Ensure that patient understands how to receive the results.

Escort patient to changing room

Common pathologies

• “Missing kidneys. Causes of a missing kidney:
• Absent
• Displaced or ectopic

Non functioning or poorly functioning

Hydronephrosis

• Ureteric obstruction
• Infection
• Neurogenic bladder
• Ureteric reflux

Pregnancy

Abnormal dilatation of pelvicalyceal system. Condition characterised by excess fluid in a kidney due to a back up of urine.

Acute pyelonephritis

kidney is larger than the contralateral kidney and shows decreased concentration of the contrast

Chronic pyelonephritis

• Results in renal scarring
• Clubing lyk appearances at the poles of the calyces

nomal calyx

. Duplex kidneys and double ureter

• ureter are the commonest congenital variant seen on IVP

. The ureters may be double on one or both sides.

Bladder calculi

are masked by contrast and difficult to see once contrast has entered the bladder, unless very large when they show as a filling defect

Bladder tumours

commonly present with haematuria

They showas irregular filling defects in the contrast filled bladder or an irregular mucosal pattern on the post micturition film They are best assessed with cystoscopy

Ureteric displacement

One or both ureters may be displaced from the usual position This may be due to a retroperitoneal tumour mass, enlarged nodes, retroperitoneal collection, or retroperitoneal fibrosis.

COMPRESSION

Its purposes is to hold as much contrast medium as possible in the upper part of the urinary tract so that the area is shown more clearly on the films It is more useful in cases where low doses of contrast medium is used There are several methods in use but the best is the one which goes around the patient only and the patient is not tied to the table and in which pressure I controlled by sphygmomanometer The pressure is applied after the five minutes film has been exposed.

It is applied between the ASIS

the compression pushed down the urine without contrast medium It should be released after 30 minutes film so that t the contrast medium may flow down the ureters into the bladder and visualize these parts of the dye stays in the calyces and pelvis, prone film may help to fill the ureters

Dangers of compression

• discomfort especially with those tie the patient to the table they should not be applied where patient has an abdominal operation or where there is abdominal infection or tumor

ii)it may impair venous return and hence fainting

Other imaging modalities

• Ultrasound
• Ct scan
• R n i
• Mri
• angiography
• tomography

cystoscopy

Nephroptosis ; a rare condition where by the kidneys drop when the pt stands erect .