Pyelogram (or pyelography or urography) is a form of imaging of the
renal pelvis and
ureter
The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epit ...
.
Types include:
*
Intravenous pyelogram
Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter.
Types include:
* Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system.
* Retrograde pyelogram ...
– In which a contrast solution is introduced through a vein into the circulatory system.
*
Retrograde pyelogram
Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter.
Types include:
* Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system.
* Retrograde pyelogram ...
– Any pyelogram in which contrast medium is introduced from the lower urinary tract and flows toward the kidney (i.e. in a "retrograde" direction, against the normal flow of urine).
*
Anterograde pyelogram (also antegrade pyelogram) – A pyelogram where a contrast medium passes from the kidneys toward the bladder, mimicking the normal flow of urine.
* Gas pyelogram – A pyelogram that uses a gaseous rather than liquid contrast medium. It may also form without the injection of a gas, when gas producing micro-organisms infect the most upper parts of urinary system.
Intravenous pyelogram
An intravenous pyelogram (IVP), also called an intravenous urogram (IVU), is a
radiological
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes:
* ''electromagnetic radiation'', such as radio waves, microwaves, infrared, visib ...
procedure used to visualize abnormalities of the
urinary system
The urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, c ...
, including the
kidney
The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blo ...
s,
ureter
The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epit ...
s, and
bladder
The urinary bladder, or simply bladder, is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine enters ...
. Unlike a
kidneys, ureters, and bladder x-ray
An abdominal x-ray is an x-ray of the abdomen. It is sometimes abbreviated to AXR, or KUB (for kidneys, ureters, and urinary bladder).
Indications
In children, abdominal x-ray is indicated in the acute setting:
*Suspected bowel obstruction or ...
(KUB), which is a plain (that is, noncontrast) radiograph, an IVP uses
contrast to highlight the
urinary tract
The urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, c ...
.
In IVP, the contrast agent is given through a vein (
intravenously
Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrie ...
), allowed to be
cleared by the kidneys and
excreted
Excretion is a process in which metabolic waste
is eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys, and skin. This is in contrast with secretion, where the substance may have specific tasks after lea ...
through the urinary tract as part of the
urine
Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excreted from the body through the urethra.
Cellular ...
.
If this is
contraindicated
In medicine, a contraindication is a condition that serves as a reason not to take a certain medical treatment due to the harm that it would cause the patient. Contraindication is the opposite of indication, which is a reason to use a certain tre ...
for some reason, a
retrograde pyelogram
Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter.
Types include:
* Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system.
* Retrograde pyelogram ...
, with the contrast flowing upstream, can be done instead.
Uses
An intravenous pyelogram is used to look for problems relating to the urinary tract.
These may include blockages or narrowing, such as due to kidney stones, cancer (such as
renal cell carcinoma
Renal cell carcinoma (RCC) is a kidney cancer that originates in the lining of the Proximal tubule, proximal convoluted tubule, a part of the very small tubes in the kidney that transport primary urine. RCC is the most common type of kidney cance ...
or
transitional cell carcinoma
Transitional cell carcinoma, also called urothelial carcinoma, is a type of cancer that typically occurs in the urinary system. It is the most common type of bladder cancer and cancer of the ureter, urethra, and urachus. It accounts for 95% of ...
),
enlarged prostate glands, and anatomical variations,
such as a
medullary sponge kidney
Medullary sponge kidney is a congenital disorder of the kidneys characterized by cystic dilatation of the collecting tubules in one or both kidneys. Individuals with medullary sponge kidney are at increased risk for kidney stones and urinary trac ...
.
They may also be able to show evidence of chronic scarring due to recurrent urinary tract infections,
and to assess for cysts
associated with polycystic kidney disease.
*Obstruction (commonly at the pelvic-ureteric junction or ''PUJ'' and the vesicoureteric junction or ''VUJ'') This is very useful.
Procedure
An injection of X-ray
contrast medium
A contrast agent (or contrast medium) is a substance used to increase the contrast of structures or fluids within the body in medical imaging. Contrast agents absorb or alter external electromagnetism or ultrasound, which is different from radio ...
is given to a patient via a needle or
cannula
A cannula (; Latin meaning 'little reed'; plural or ) is a tube that can be inserted into the body, often for the delivery or removal of fluid or for the gathering of samples. In simple terms, a cannula can surround the inner or outer surfaces ...
into the
vein
Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenat ...
,
typically in the antecubital fossa of arm. The contrast is ''excreted'' or removed from the bloodstream via the kidneys, and the contrast media becomes visible on X-rays almost immediately after injection.
X-rays
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nbs ...
are taken at specific time intervals to capture the contrast as it travels through the different parts of the urinary system.
At the end of the test, a person is asked to pass urine and a final X-ray is taken.
Before the test, a person is asked to pass urine so that their bladder is emptied.
They are asked to lie flat during the procedure.
Normal appearances
Immediately after the contrast is administered, it appears on an X-ray as a 'renal blush'. This is the contrast being filtered through the cortex. At an interval of 3 minutes, the renal blush is still evident (to a lesser extent) but the calyces and
renal pelvis are now visible. At 9 to 13 minutes the contrast begins to empty into the
ureters
The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epit ...
and travel to the
bladder
The urinary bladder, or simply bladder, is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine enters ...
which has now begun to fill. To visualize the bladder correctly, a post micturition X-ray is taken, so that the bulk of the contrast (which can mask a pathology) is emptied.
An IVP can be performed in either emergency or routine circumstances.
Emergency IVP
This procedure is carried out on patients who present to an Emergency department, usually with severe
renal colic
Renal colic is a type of abdominal pain commonly caused by obstruction of ureter from dislodged kidney stones. The most frequent site of obstruction is the vesico-ureteric junction (VUJ), the narrowest point of the upper urinary tract. Acute ob ...
and a positive
hematuria
Hematuria or haematuria is defined as the presence of blood or red blood cells in the urine. “Gross hematuria” occurs when urine appears red, brown, or tea-colored due to the presence of blood. Hematuria may also be subtle and only detectable w ...
test. In this circumstance the attending physician requires to know whether a patient has a kidney stone and if it is causing any obstruction in the urinary system.
Patients with a positive find for
kidney stones
Kidney stone disease, also known as nephrolithiasis or urolithiasis, is a crystallopathy where a calculus (medicine), solid piece of material (kidney stone) develops in the urinary tract. Kidney stones typically form in the kidney and leave the ...
but with no obstruction are sometimes discharged based on the size of the stone with a follow-up appointment with a urologist.
Patients with a kidney stone ''and'' obstruction are usually required to stay in hospital for monitoring or further treatment.
An Emergency IVP is carried out roughly as follows:
*plain
KUB or
abdominal X-ray
An abdominal x-ray is an Projectional radiography, x-ray of the abdomen. It is sometimes abbreviated to AXR, or kidneys, ureters, and bladder, KUB (for kidneys, ureters, and urinary bladder).
Indications
In children, abdominal x-ray is indicated ...
;
*an injection of
contrast media
A contrast agent (or contrast medium) is a substance used to increase the contrast of structures or fluids within the body in medical imaging. Contrast agents absorb or alter external electromagnetism or ultrasound, which is different from radiop ...
, typically 50 ml;
*delayed abdominal X-ray, taken at roughly 15 minutes post injection.
If no obstruction is evident on this film a post-micturition film is taken and the patient is sent back to the Emergency department. If an obstruction ''is'' visible, a post-micturition film is still taken, but is followed up with a series of radiographs taken at a "double time" interval. For example, at 30 minutes post-injection, 1 hour, 2 hours, 4 hours, and so forth, until the obstruction is seen to resolve. This time delay can give important information to the urologist on where and how severe the obstruction is. This is very useful.
Routine IVP
This procedure is most common for patients who have unexplained microscopic or macroscopic hematuria. It is used to ascertain the presence of a tumour or similar anatomy-altering disorders. The sequence of images is roughly as follows:
*plain or Control
KUB image;
*immediate X-ray of just the renal area;
*5 minute X-ray of just the renal area.
*15 minute X-ray of just the renal area.
At this point, compression may or may not be applied (this is contraindicated in cases of obstruction).
In pyelography, compression involves pressing on the lower abdominal area, which results in distension of the upper urinary tract.
*If compression is applied: a 10 minutes post-injection X-ray of the renal area is taken, followed by a KUB on release of the compression.
*If compression is not given: a standard KUB is taken to show the ureters emptying. This may sometimes be done with the patient lying in a
prone position
Prone position () is a body position in which the person lies flat with the chest down and the back up. In anatomical terms of location, the dorsal side is up, and the ventral side is down. The supine position is the 180° contrast.
Etymolo ...
.
*A post-micturition X-ray is taken afterwards. This is usually a coned bladder view.
Image assessment
The kidneys are assessed and compared for:
* Regular appearance, smooth outlines, size, position, equal filtration and flow.
The ureters are assessed and compared for:
* Size, a smooth regular and symmetrical appearance. A 'standing column' is suggestive of a partial obstruction.
The bladder is assessed for:
* Regular smooth appearance and complete voiding.
Risks
Intravenous pyelograms use
ionizing radiation, which involves risk to healthy tissues (
potentially encouraging cancer or
risking birth defects).
Therefore, they are often now replaced by
ultrasonography
Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except that humans cannot hear it. This limit varies fr ...
and more recently by
magnetic resonance imaging (MRI), which use sound waves or magnetism instead. Also, the
iodinated contrast
Iodinated contrast is a form of intravenous radiocontrast agent containing iodine, which enhances the visibility of vascular structures and organs during radiographic procedures. Some pathologies, such as cancer, have particularly improved visib ...
medium used in contrast CT and contrast radiography can cause
allergic reaction
Allergies, also known as allergic diseases, refer a number of conditions caused by the hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic derma ...
s, including
severe ones.
The contrast dye may also be
toxic to the kidneys.
Because a cannula is inserted, there is also a risk of a
cannula site infection, that may cause fevers or redness of the cannula area.
Contraindications
*
Metformin
Metformin, sold under the brand name Glucophage, among others, is the main first-line medication for the treatment of type 2 diabetes, particularly in people who are overweight. It is also used in the treatment of polycystic ovary syndrome. ...
use: Historically, the drug metformin has been required to stop 48 hours pre and post procedure, as it known to cause a reaction with the contrast agent. However the newest guidelines published by the Royal College of Radiologists suggests this is not as important for patients having <100mls of contrast, who have a
normal kidney function. If kidney impairment is found before administration of the contrast, metformin should be stopped 48 hours before and after the procedure.
* Contrast allergy: If the patient has any previous history of adverse or moderate reactions to contrast medium.
* Patient with significantly decreased kidney function ;because contrast media can be nephrotoxic and worsen kidney function
Anterograde pyelogram
Antegrade pyelography is the procedure used to visualize the upper collecting system of the urinary tract, i.e.,
kidney
The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blo ...
and
ureter
The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epit ...
.
It is done in cases where excretory or
retrograde pyelography has failed or contraindicated, or when a
nephrostomy
A nephrostomy is an artificial opening created between the kidney and the skin which allows for the urinary diversion directly from the upper part of the urinary system (renal pelvis).
An urostomy is a related procedure performed more distally a ...
tube is in place or delineation of upper tract is desired. It is commonly used to diagnose upper tract obstruction,
hydronephrosis
Hydronephrosis describes hydrostatic dilation of the renal pelvis and calyces as a result of obstruction to urine flow downstream. Alternatively, hydroureter describes the dilation of the ureter, and hydronephroureter describes the dilation of t ...
, and ureteropelvic junction obstruction. In this, radiocontrast dye is injected into the renal pelvis and
X-rays
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nbs ...
are taken. It provides detailed anatomy of the upper collecting system. As it is an invasive procedure, it is chosen when other non-invasive tests are non confirmatory or contraindicated and patient monitoring is required prior and after the procedure.
Retrograde pyelogram
A retrograde pyelogram is a
medical imaging procedure in which a
radiocontrast agent
Radiocontrast agents are substances used to enhance the visibility of internal structures in X-ray-based imaging techniques such as computed tomography ( contrast CT), projectional radiography, and fluoroscopy. Radiocontrast agents are typically i ...
is injected into the
ureter
The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In a human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epit ...
in order to visualize the ureter,
bladder
The urinary bladder, or simply bladder, is a hollow organ in humans and other vertebrates that stores urine from the kidneys before disposal by urination. In humans the bladder is a distensible organ that sits on the pelvic floor. Urine enters ...
, and
kidney
The kidneys are two reddish-brown bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blo ...
s with
fluoroscopy
Fluoroscopy () is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a physician to see the internal structure and function ...
or
radiography
Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeu ...
, using plain
X-ray
An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...
s.
The flow of contrast (up from the bladder to the kidney) is opposite the usual
outbound flow of urine, hence the ''retrograde'' ("moving backwards") name.
A retrograde pyelogram may be performed to find the cause of
blood in the urine
Hematuria or haematuria is defined as the presence of blood or red blood cells in the urine. “Gross hematuria” occurs when urine appears red, brown, or tea-colored due to the presence of blood. Hematuria may also be subtle and only detectable w ...
, or to locate the position of a stone or narrowing, tumour or clot, as an adjunct during the placement of ureteral stents.
It can also be used
ureteroscopy
Ureteroscopy is an examination of the upper urinary tract, usually performed with a ureteroscope that is passed through the urethra and the bladder, and then directly into the ureter. The procedure is useful in the diagnosis and treatment of diso ...
, or to delineate renal anatomy in preparation for surgery. Retrograde pyelography is generally done when an intravenous
excretory
Excretion is a process in which metabolic waste
is eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys, and skin. This is in contrast with secretion, where the substance may have specific tasks aft ...
study (
intravenous pyelogram
Pyelogram (or pyelography or urography) is a form of imaging of the renal pelvis and ureter.
Types include:
* Intravenous pyelogram – In which a contrast solution is introduced through a vein into the circulatory system.
* Retrograde pyelogram ...
or contrast
CT scan) cannot be done because of
renal disease
Kidney disease, or renal disease, technically referred to as nephropathy, is damage to or disease of a kidney. Nephritis is an inflammatory kidney disease and has several types according to the location of the inflammation. Inflammation can b ...
or allergy to intravenous contrast.
Relative contraindications include the presence of infected urine, pregnancy (because of radiation), or allergy to the contrast.
Because a pyelogram involves cystoscopy, it may cause sepsis, infection or bleeding,
and may also cause nausea and vomiting.
The dye may also be
toxic to the kidneys.
Before the procedure, a person is usually asked to complete a safety check assessing for potential risks, such as pregnancy or allergy.
They may be asked to take an enema, and not to eat for some hours.
An intravenous drip is inserted and a person is given some sedation before a cystoscope, which is a flexible tube, is inserted into the bladder via the urethra.
10 ml of contrast
is usually injected during
cystoscopy
Cystoscopy is endoscopy of the urinary bladder via the urethra. It is carried out with a cystoscope.
The urethra is the tube that carries urine from the bladder to the outside of the body.
The cystoscope has lenses like a telescope or microscop ...
, which is where a flexible tube is inserted into the bladder and to the lower part of the ureter.
Fluoroscopy
Fluoroscopy () is an imaging technique that uses X-rays to obtain real-time moving images of the interior of an object. In its primary application of medical imaging, a fluoroscope () allows a physician to see the internal structure and function ...
, or dynamic X-rays, is typically used for visualization. The procedure is usually done under general or regional
anesthesia.
Risks of complications of the procedure includes: pyelosinus extravasation (contrast going into
renal sinus
The renal sinus is a cavity within the kidney which is occupied by the renal pelvis, renal calyces, blood vessels, nerves and fat. The renal hilum extends into a large cavity within the kidney occupied by the renal vessels, minor renal calyces, m ...
) and pyelotubular (contrast going into
collecting duct
The collecting duct system of the kidney consists of a series of tubules and ducts that physically connect nephrons to a minor calyx or directly to the renal pelvis. The collecting duct system is the last part of nephron and participates in elect ...
) reflux of contrast due to overfilling of the urinary system. It can cause pain, fever and chills. Infection may be accidentally introduced into the urinary tract. There can be also damage or perforation of renal pelvis or ureter.
Rarely,
acute renal failure
Acute kidney injury (AKI), previously called acute renal failure (ARF), is a sudden decrease in kidney function that develops within 7 days, as shown by an increase in serum creatinine or a decrease in urine output, or both.
Causes of AKI are c ...
can occur.
Treatment
Depending on the outcome and diagnosis following an IVP, treatment may be required for the patient. These include
surgery,
lithotripsy
Lithotripsy is a non-invasive procedure involving the physical destruction of hardened masses like kidney stones, bezoars or gallstones. The term is derived from the Greek words meaning "breaking (or pulverizing) stones" ( litho- + τρίψω r ...
,
ureteric stent
A ureteral stent (pronounced you-REE-ter-ul), or ureteric stent, is a thin tube inserted into the ureter to prevent or treat obstruction of the urine flow from the kidney. The length of the stents used in adult patients varies between 24 and 30&nb ...
insertion and
radiofrequency ablation
Radiofrequency ablation (RFA), also called fulguration, is a medical procedure in which part of the electrical conduction system of the heart, tumor or other dysfunctional tissue is ablated using the heat generated from medium frequency alternati ...
. Sometimes no treatment is necessary as stones <5mm can be passed without any intervention.
Future
IVP is an affordable yet useful
imaging
Imaging is the representation or reproduction of an object's form; especially a visual representation (i.e., the formation of an image).
Imaging technology is the application of materials and methods to create, preserve, or duplicate images.
...
modality and continues to be relevant in many parts of the world. In the developed world, however, it has increasingly been replaced by contrast
computed tomography of the urinary tract (
CT urography), which gives greater detail of anatomy and function.
History
The technique of IVP was originally developed by
Leonard Rowntree
Leonard George Rowntree (1883–1959) was a Canadian physician and medical researcher who was credited with founding the research tradition at the Mayo Clinic. He is most well known for pioneering kidney research including the Rowntree test for k ...
of the
Mayo Clinic in the 1920s.
IVP was previously the test of choice for diagnosing ureter obstruction secondary to urolithiasis but in the late 1990s non-contrast computerized tomography of the abdomen and pelvis replaced it because of its increased specificity regarding etiologies of obstruction.
Now, because of increased accuracy computed tomography and ultrasounds of the renal tract are used; ultrasounds additionally do not involve radiation.
Etymologically
Etymology ()The New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time". is the study of the history of the form of words an ...
, urography is
contrast radiography
Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view the internal form of an object. Applications of radiography include medical radiography ("diagnostic" and "therapeut ...
of the
urinary tract
The urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, c ...
(''
uro-'' + ''
-graphy
The English suffix -graphy means a "field of study" or related to "writing" a book, and is an anglicization of the French ''-graphie'' inherited from the Latin ''-graphia'', which is a transliterated direct borrowing from Greek.
Arts
* Cartogr ...
''), and pyelography is contrast radiography of the
renal pelvis (''
pyelo-
The renal pelvis or pelvis of the kidney is the funnel-like dilated part of the ureter in the kidney. It is formed by the covnvergence of the major calyces, acting as a funnel for urine flowing from the major calyces to the ureter. It has a mucous ...
'' + ''
-graphy
The English suffix -graphy means a "field of study" or related to "writing" a book, and is an anglicization of the French ''-graphie'' inherited from the Latin ''-graphia'', which is a transliterated direct borrowing from Greek.
Arts
* Cartogr ...
''), but in present-day standard medical
usage
The usage of a language is the ways in which its written and spoken variations are routinely employed by its speakers; that is, it refers to "the collective habits of a language's native speakers", as opposed to idealized models of how a language ...
, they are
synonymous.
See also
*
Urodynamics
Urodynamic testing or urodynamics is a study that assesses how the bladder and urethra are performing their job of storing and releasing urine. Urodynamic tests can help explain symptoms such as:
* incontinence
* frequent urination
* sudden, str ...
*
Urology
Urology (from Greek οὖρον ''ouron'' "urine" and '' -logia'' "study of"), also known as genitourinary surgery, is the branch of medicine that focuses on surgical and medical diseases of the urinary-tract system and the reproductive org ...
References
External links
eMedicineRadiologyInfo: IVPCardiovascular and Interventional Radiological Society of EuropeRCR guidelines
{{Medical imaging
Urologic imaging
Projectional radiography