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Diagnostic Tests & Medical Procedures
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[A]
Diagnostic Tests A thru ZAngiography
The use of angiography as a purely diagnostic radiologic treatment has steadily declined since the 1980s. However, during the same period, the therapeutic applications of angiography have expanded considerably.

Angiography provides a complete examination of the arterial supply to an organ. For studies of the kidney, the aorta and renal arteries are typically visualized. In this study, a catheter is used to inject a contrast agent (dye) into the major blood vessel in the body. The amount of dye used depends on the size and function of the kidneys and renal blood flow. Throughout the dye injection procedure, X-ray images are taken at a rapid rate to permit visualization of the kidney and associated blood vessels.

Possible complications may include reaction to the dye, bleeding and injury to the artery.

Antegrade Pyelography
Antegrade pyelography uses special contrast agent (dye) to produce detailed X-ray pictures of the upper urinary tract (kidney and ureter). It is commonly used to diagnose conditions including hydronephrosis, ureteropelvic junction obstruction and obstruction of the ureters.

This test is performed in a hospital radiology department or in a health care provider's office by a radiologist or X-ray technician. The kidneys will initially be examined with an ultrasound probe or a CT scan. After they are located, the overlying skin will be anesthetized and a needle will be passed directly into the kidney. This needle is used to inject dye to outline the renal collection system (part of the urinary tract draining urine between the kidney and bladder) on X-ray images and detect any blockages or obstructions.

While pyelography is considered generally safe, the major risk involves a reaction to the iodine-based dye. Minor reactions include hot flashes, nausea and vomiting. These are usually treated successfully with antihistamines, drugs that reduce the effects of the body's inflammatory compound, histamine. In very rare circumstances, more severe complications -- breathing difficulties, low blood pressure, swelling of the mouth or throat and even cardiac arrest -- can occur.

There is relatively low radiation exposure during this test. However, a patient who is or may be pregnant should notify their physician prior to this examination, as a fetus is susceptible to the risks associated with radiation.

[B]
Top of PageBiopsy
A biopsy is conducted by removing a sample of skin or tissue from a patient's body for examination under a microscope to diagnose a medical condition, especially cancer.

A biopsy can be obtained of the skin by removing a small amount of tissue with a special instrument. This can be done with local anesthesia to avoid pain. Biopsies of the prostate or kidney are typically obtained with specially designed needles that allow for the removal of small amounts of tissue. The needle is guided with ultrasound or special X-rays such as a CT scan. Biopsies can also be obtained from the bladder or ureter with specially designed endoscopes that are passed into these structures through normal urine passageways.

After the biopsy specimen is obtained, it is sent for examination to a pathologist, who prepares a written report with information designed to help the doctor manage the patient's condition properly.

[C]
Top of PageCT Scan
Computed axial tomography, also known as CAT scan or CT scan, is an imaging technique that is a widely regarded tool for evaluating the genitourinary tract. CT scanning combines X-rays and computer calculations to produce precisely detailed cross-sectional slices of images of the body's tissues and organs. More specifically, very small, controlled beams of X-rays, rotating in a continuous 360-degree motion around the patient, pass through the tissue as an array of detectors measure thousands of X-ray images or profiles. Computer calculations based on those multiple measures produce the detailed pictures reflected on a screen. These images can be stored, viewed on a monitor or printed on film. In addition, stacking the "slices" of images can also create three-dimensional images of the body's internal structures.

Since CT scans can distinguish between solid and liquid, it is extremely valuable in examining the type and extent of kidney tumors or other masses, such as stones or cysts, distorting the urinary tract. CT technology, however, is also enhanced by other factors. Intravenous injections of contrast agent (dye) intensify the images. CT scans have improved speed and accuracy by gathering volumes of continuous kidney and urinary data in seconds with no gaps between images.

Specialized applications of CT can be performed in specific clinical circumstances. For example, three-dimensional reconstructions of the kidney and blood supply may show vascular abnormalities and provide "road maps" for planning surgeries.

The test is performed in a radiology department by a technician under the supervision of a radiologist. The patient will be asked to lie in a certain position on a narrow table that slides into the center of the scanner. Dye may also be administered into a vein in the hand or arm. The technician will issue instructions to the patient regarding body position and breathing during this test. Upon test completion, the patient can resume their normal daily activities.

CT scanning is a safe, efficient and effective technology that produces minimal risks. The major risk involves a reaction to any iodine-based dye that may be used. Minor reactions to the dye may include hot flashes, nausea and vomiting, which are usually treated successfully with antihistamines. In very rare circumstances, more severe complications -- breathing difficulties, low blood pressure, swelling of the mouth or throat and even cardiac arrest -- can occur.

There is relatively low radiation exposure during this test. However, a patient who is or may be pregnant should notify their physician prior to this examination as a fetus is susceptible to the risks associated with radiation.

Top of PageContrast and Radionuclide Cystography
Cystography uses X-rays and contrast agents (dyes) to study the bladder in detail. With it, urologists can check the structure of the organ while identifying disorders such as tumors infections and stones. Vesicoureteral reflux or urine backflow to the kidneys can often be identified with this study.

During past decades, urologists have added a nuclear version of this test, called a radionuclide cystogram, to their arsenal, particularly to study reflux (see radionuclide cystogram). Many physicians believe this technology is a better surveillance tool for tracing the migration of urine through the urinary tract because it uses less radiation exposure (some estimates suggest up to 200 times) than the conventional cystogram. It also does not rely on fluoroscopy, a radiological technique for visually examining the tissue, which contributes to the higher radiation exposures.

The doctor will insert a catheter through the patient's urethra and into the bladder. The dye or radioactive agent is then injected through the catheter into the bladder. X-ray pictures are taken at various stages of filling, from various angles, to visualize the bladder. Additional films are taken after drainage of the dye (see voiding cystourethrography). The procedure takes about an hour and a half and the patient may be asked to wait while films are developed. In surveying for vesicoureteral reflux, the urologist employs the same steps, using the radio-pharmaceutical, to collect continuous images every 10 to 15 seconds. While conventional voiding cystograms are still necessary to evaluate the male urethra for posterior valves and bladder trauma, the majority of reflux studies today are done effectively with radionuclide cystography.

While the risks are low, patients may experience urinary tract infections from the catheter, and, in rare circumstances, damage to the urethra, bladder or nearby structures can occur. Another risk is reaction to the contrast dye. Minor reactions include hot flashes, nausea and vomiting. These are usually treated successfully with antihistamines, drugs that reduce the effects of the body's inflammatory compound, histamine. In very rare circumstances, more severe complications -- breathing difficulties, low blood pressure, swelling of the mouth or throat and even cardiac arrest -- can occur.

Top of PageCystometry
Cystometry is a bladder function test to help diagnose problems with urination, including incontinence, urinary retention and recurrent urinary tract infections. It measures pressure and volume of fluid in the bladder during filling, storage and urination (see uroflowmetry).

Generally, no preparation is necessary prior to this test, although the patient may be asked to stop taking certain medications in advance.

The test begins by having the patient empty their bladder as much as possible. A catheter is then inserted into the urethra until it reaches the bladder. Measurements are taken of residual urine volume (amount remaining in the bladder after urination) and bladder pressure. Pressure measurements may require a rectal probe to account for the contribution of the abdominal muscles to the pressure recording. The bladder is then gradually filled with water, saline solution, carbon dioxide gas or a contrast solution for X-ray analysis, depending on the type of study being done. The patient is asked to describe any sensations experienced during the filling (e.g., temperature changes, feeling of fullness, etc.). Once the bladder is completely full, the patient is asked to begin urinating. Pressure and volume measurements are taken again including flow rate and pressure.

The patient may experience some urinary frequency or urgency and the urine may be slightly pink for up to 24 hours following the test but they can resume their daily activities immediately. If discomfort persists, fever develops or urine appears bright red, a physician should be notified.

[D - I]
Top of PageIntravenous Pyelogram (IVP)
The most common of all urologic studies and is also commonly referred to as excretory urogram. It is a test that uses contrast agent (dye) that is injected into a vein to outline the kidneys, ureters and bladder on an X-ray. A urologist is likely to order this test if a patient complains of pain in their side, blood in the urine (hematuria) or any stone-related symptoms. It may also be utilized as a screening test to prompt your urologist to obtain another imaging test for further information.

This test is performed in a hospital radiology department or in a health care provider's office by an X-ray technician under the supervision of a radiologist or urologist. The patient will commonly be placed on a restricted diet 24 hours prior to the test and will be asked to urinate immediately prior to the test to ensure that the bladder is empty. The patient will then be asked to lie on their back and to remain still. A preliminary film of the abdomen and pelvis is a basic part of this examination and this is usually done without dye. This helps to determine the proper radiographic technique and patient positioning. A single film of the abdomen that includes the pubic bone may suffice in some patients, whereas in others, an additional film is focused on the kidneys. A full set of specific kidney films may be of value in a patient suspected of having small kidney stones. The dye will travel through the bloodstream to the kidneys and the kidneys will filter the dye out of the blood and send it down through the ureters into the bladder. While this is occurring, X-rays are taken at specific time intervals, from two to 10 minutes. These X-rays will show any tumors, cysts, stones or other structural and functional abnormalities.

At the end, the patient will be asked to urinate for final images to see how well the bladder has emptied. The entire test can take up to one hour. The patient can immediately resume their daily activities.

The primary risk of IVP is a reaction to the dye. The overall incidence rate for reactions ranges from three to 13 percent. Minor reactions include hot flashes, nausea and vomiting. These are usually treated successfully with antihistamines, drugs that reduce the effects of the body's inflammatory compound, histamine. In very rare circumstances, more severe complications -- breathing difficulties, low blood pressure, swelling of the mouth or throat and even cardiac arrest -- can occur. Statistics estimate major reactions in one in 200 to one in 2,000 patients.

Patients with certain health factors -- a history of hay fever, asthma or hives -- are at greater risk as are those with congestive heart failure, diabetes and a prior reaction. Administering antihistamines or steroids prior to the exam may prevent any reactions. Also, nonionic contrast agents are dyes that have been recently developed which have lowered the incidence of adverse reactions.

There is relatively low radiation exposure during this test. However, a patient who is or may be pregnant should notify their physician prior to this examination as a fetus is susceptible to the risks associated with radiation.

[J - L]
Top of PageKidney (Renal) Nuclear Medicine Scan
A kidney (renal) nuclear medicine scan is used to diagnose certain kidney diseases. It is an excellent diagnostic tool because it shows not only the anatomy of the kidneys, but the function of them as well. This additional "functional information" allows radionuclide imaging to diagnose certain diseases and various medical conditions much sooner than other imaging examinations.

Prior to this test the patient should advise their physician if they are pregnant or breastfeeding and if they are on any medications.

This test is performed in a hospital radiology department or in a health care provider's office by a nuclear medicine technologist under the supervision of a physician. During this test, the patient will be positioned on an exam table and they are asked to lie still to prevent blurring of the images that will be taken. For this test, a radiosotope "tracer," a molecule to which a radioactive atom or "tag" has been attached so that it can be followed through the kidney system with special detectors, is injected into a vein. Immediately after the tracer is injected, imaging begins. A gamma camera detects the radioactivity and the images may be projected on a computer screen and then stored on film.

This test can take 45 minutes to three hours, depending on the goals of the test. Patients can resume their normal activities immediately after the test as tracers are passed naturally from the body.

Radionuclide imaging is considered safe since it does not carry the risk of toxicity or allergic reaction found with intravenous dyes. Also since the radioisotope tracer exposes the patient to less radiation than an X-ray.

[M - O]
Top of PageMagnetic Resonance Imaging (MRI)
Magnetic resonance imaging (MRI) is a superior technique that uses radio waves and a strong magnetic field to provide remarkably clear pictures. As such, it offers an alternative to patients who react to radiopaque intravenous dye. Because of its ability to show soft tissues in exquisite detail, this technology can detect disease and detail blood vessels or other structures. In the kidney system, for example, an MRI can distinguish a hollow cyst from a solid mass, producing excellent three-dimensional images of any tumor's shape. In particular, its supersensitivity can help urologists identify and measure the spread of kidney cancer into the renal vein and inferior vena cava, the large vessel that returns blood to the heart. But while useful in evaluating kidney transplant donors, MRI has limited applicability for the urinary tract since the non-specificity of its signals makes it ineffective in detecting calcifications and bladder abnormalities.

MRI is unique among imaging methods because, unlike radiographs (X-rays,), CT scan and even radioisotope studies, it does not use ionizing radiation. Instead, MRI uses a strong magnet, radio waves and computers to create detailed images of the body. More specifically, lying inside a massive hollow magnet, a patient is exposed to short bursts of powerful non-ionizing radio wave energy, directed at protons, the nuclei of hydrogen or water atoms, in the body. Radio signals generated by first "exciting" and then "relaxing" those protons, are computer-processed to form digital images, reflecting different types of tissue. Typical MRI examinations consist of multiple imaging sequences, each lasting from two to 15 minutes. While these techniques continue to evolve, the beauty of current MRI is that it can be tailored for any clinical question.

This test is performed in a hospital radiology department or in a health care provider's office by a technician under the supervision of a physican. No patient preparation is necessary prior to this test. The patient will be asked to lie on a narrow table, which slides into a large tunnel-like tube within the scanner. The patient's head will be placed in a padded plastic cradle or on a pillow and the table will then slide into the scanner. The patient will be instructed to breath quietly and normally but to refrain from any movement, coughing or wiggling. The technician will be able to communicate with the patient during this test through the use of an intercom. While the scanner is taking images, the patient will hear rapidly repeating, loud thumping noises coming from the walls of the scanner, so earplugs are usually provided to the patient to reduce the noise. The entire test usually takes between 30 and 60 minutes to complete. Following the test, the patient may resume their normal daily activities.

For generally healthy individuals, MRI poses no risk. But patients with pacemakers, aneurysm clips, ear implants and metallic pieces in vital body locations cannot be imaged safely.

[P - Q]
Top of PageProstate Cancer Screening
Currently, digital rectal examination (DRE) and prostate specific antigen (PSA) are used for prostate cancer detection. The age at which time screening for prostate cancer should begin is not known with certainty. However, most experts agree that healthy men over the age of 50 should consider prostate cancer screening with a DRE and PSA test. Screening should occur earlier, at age 40, in those who are at a higher risk of prostate cancer such as African-American men or those with a family history of prostate cancer.

DRE Test: The DRE is performed with the man either bending over, lying on his side or with his knees drawn up to his chest on the examining table. The physician inserts a gloved finger into the rectum and examines the prostate gland, noting any abnormalities in size, contour or consistency. DRE is inexpensive, easy to perform and allows the physician to note other abnormalities such as blood in the stool or rectal masses, which may allow for the early detection of rectal or colon cancer. However, DRE is not the most effective way to detect an early cancer so it should be combined with a PSA test.

PSA Test: The PSA test is usually performed in addition to DRE and increases the likelihood of prostate cancer detection. The test measures the level of PSA, a substance produced only by the prostate, in the bloodstream.

This blood test can be performed in a clinical laboratory, hospital or physician's office and requires no special preparation on the part of the patient. A tourniquet or rubber strap is tied around the upper arm to mildly restrict the flow of blood and keep blood in the vein. Then, a needle with a tube-like container attached is inserted into a vein, usually in the bend of the elbow or the top of the hand. After a sufficient sample of blood is obtained, the needle is withdrawn, a bandage is placed on the puncture site and firm pressure is held until the bleeding stops. The entire test takes less than five minutes and produces only mild discomfort. After, the patient may experience slight bruising at the puncture site.

Very little PSA escapes from a healthy prostate into the bloodstream, but certain prostatic conditions can cause larger amounts of PSA to leak into the blood. One possible cause of a high PSA level is benign (non-cancerous) enlargement of the prostate, otherwise known as BPH. Prostate cancer is another possible cause of an elevated PSA level. The frequency of PSA testing remains a matter of some debate. The American Urological Association (AUA) encourages men to have annual PSA testing starting at age 50. The AUA also recommends annual PSA testing for men over the age of 40 who are African-American or have a family history of the disease (for example, a father or brother who was diagnosed with prostate cancer). Some experts have suggested that men with an initial normal DRE and PSA level of less than 2.5 ng/ml can have PSA testing performed every two years. Recently, several refinements have been made in the PSA blood test in an attempt to determine more accurately who has prostate cancer and who has false-positive PSA elevations caused by other conditions like BPH. These refinements include PSA density, PSA velocity, PSA age-specific reference ranges and use of total-to-free PSA ratios. Such refinements may increase the ability to detect cancer and these should be discussed with your physician.

Currently, it is recommended that both a DRE and PSA test be used for the early detection of prostate cancer. It is important to realize that in most cases an abnormality in either test is not due to cancer but to benign conditions, the most common being BPH. For instance, it has been shown that only 18 to 30 percent of men with serum PSA values between 4 and 10 ng/ml have prostate cancer. This number rises to approximately 42 to 70 percent for those men whose PSA values exceeding 10 ng/ml.

[R - S]
Top of PageRadionuclide Cystogram
Also referred to as bladder scan, radionuclide cystogram is a diagnostic nuclear test that uses radioactive material to outline the bladder to diagnose conditions such as reflux, distention or incomplete emptying.

The test is performed in a radiology department by a technician under a physician's supervision. Prior to this test, the patient requires no special preparation. The patient is asked to lie on a scanner table. After cleaning the urethral opening, a catheter is placed into the urethra and into the bladder. A solution containing radioactive material is instilled into the bladder until the bladder is full or the patient indicates a feeling of fullness. The bladder is then scanned and various images are taken of the bladder and kidneys. The patient may also be asked to urinate while being scanned. When testing for incomplete bladder emptying, images are taken when the bladder is full and then again after urination.

The patient may experience some discomfort during insertion of the catheter. After the scan, there may be a slight discomfort when urinating for up to 48 hours and the urine may be slightly pink. If discomfort persists, fever develops or urine appears bright red, a physician should be notified.

Top of PageRetrograde Pyelography
Like an IVP, retrograde pyelography uses special contrast agent (dye) to produce detailed X-ray pictures of the ureters and kidneys. The difference is that in retrograde pyelography the dye is injected directly into the ureters rather than into a vein. While newer diagnostic technologies have replaced this test for many functions, retrograde pyelography may still yield better definition of the upper urinary tract, particularly the ureter and kidney. Commonly performed when an IVP produces an inadequate image, it also complements cystoscopy while investigating a patient with hematuria or recurrent or suspected cancer.

This test is performed in a hospital radiology department or in a health care provider's office by a urologist and is typically carried out under general anesthesia. Cystoscopy is performed and the small catheter is inserted into the opening of the ureter in the bladder. Dye is injected and fluoroscopy is performed to visualize the ureters and kidneys. The entire study can take 15 to 30 minutes and is done on an outpatient basis.

While pyelography is considered generally safe, the major risk involves a reaction to the iodine-based dye. Minor reactions include hot flashes, nausea and vomiting. These are usually treated successfully with antihistamines, drugs that reduce the effects of the body's inflammatory compound, histamine. In very rare circumstances, more severe complications -- breathing difficulties, low blood pressure, swelling of the mouth or throat and even cardiac arrest -- can occur. There may be additional problems such as a urinary tract infection or pain afterward (see cystoscopy).

There is relatively low radiation exposure during this test. However, a patient who is or may be pregnant should notify their physician prior to this examination as a fetus is susceptible to the risks associated with radiation.

[T]
Top of PageTesticular Self Examination (TSE)
A testicular self-examination is an examination of the testicles to help detect testicular cancer in the early stages. It is important to do testicular exams every month in order to detect any abnormalities.

The best time to examine your testicles is right after a hot bath or shower. The scrotal skin is most relaxed at this time and the testicles can be felt more easily. The exam should be done while standing and will only takes few minutes.
    How to do a testicular self-exam:
  • Examine the scrotum visually for swelling.
  • Gently feel the scrotal sac to locate a testicle.
  • Examine each testicle separately by firmly and gently rolling each testicle between the thumb and fingers of both hands to examine the entire surface.
  • It is important to note that it is normal for one testicle to be slightly larger than the other and to feel a cord-like structure - the epididymis - on the top and back of each testicle.
  • If you find a small hard lump (pea-size), swelling or notice any other concerning differences, contact your urologist as soon as you can. Also, have your physician evaluate you if you experience pain or tenderness.

[U - Z]
Top of PageUltrasound Imaging
An ultrasound examination, also commonly referred to as a sonogram, is a painless, diagnostic technique that makes use of the behavior of sound waves in the human body. When these sound waves are transmitted into the body, they are reflected in specific ways by specific tissues and organs. These reflected waves can be used to produce images of internal organs without the pain or exposure to radiation.

Depending on the reason for the study and the circumstances, ultrasound imaging may be performed in the urologist's office, in the hospital or in an outpatient facility.

In most cases, very little preparation is needed for an ultrasound examination. Some examinations, such as a bladder scan for residual urine, require limited experience while others, such as ultrasound examinations of the kidneys, testicles or prostate, require more experience or expertise. The patient will be asked to lie down on the examination table. A clear, water-based gel is applied to the skin over the area to be examined. This gel helps with the transmission of the sound waves. A transducer, which is a hand-held probe, is then moved over that area. Prostate ultrasound examinations are performed by placing a specially designed probe into the rectum.

There is no risk of radiation with this study and the patient can resume their daily activities immediately following this test.

Top of PageUrine Cytology
Urine cytology is an examination of the urine to screen for cancer cells. In preparation for this test, males must wipe the head of the penis and females need to wash the area between the lips of the vagina with soapy water and rinse. As the patient begins to urinate, they should allow a small amount to fall into the toilet bowel to clear the urethra of any contaminates. Then, in a sterile container, they should catch about three to six ounces of urine and then remove the container from the urine stream. The patient then gives the container containing the urine sample to their health care provider.

The urine sample will be sent out to a laboratory for evaluation by a pathologist who looks for the presence of cancer cells within the urine. Frequently, the second or subsequent urinations during the day and not the first urination of the day are examined.

The patient can resume their daily activities immediately following this test.

Top of PageUrologic Radiology
Science has given urologists a bevy of tools to probe the most private parts of the body in diagnosing urinary and renal disease. Every modern imaging technology, from conventional X-rays to radionuclide imaging, has found its way into urologic radiology's arsenal. The good news for physicians is that they have many options to explore the kidneys, ureters, bladder and surrounding structures. The better news for patients is that today's tests are thorough, relatively pain-free and often quick. But would you know what your doctor means when he or she talks of "retrograde pyelography" or "radionuclide scans?" The information below should give you the basics.

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