What is the difference between a cholecystography and intravenous pyelography

The main risk of an IVP test is a reaction to the dye. Such reactions are not common. Reactions occur in anywhere from 3 to 13 out of people having an IVP. In general, reactions are minor, and consist of:.

These are often treated with antihistamines drugs that reduce the histamines in your body from an allergic reaction. In these cases, you may be given antihistamines or steroids before the exam.

This will reduce a reaction to the x-ray dye. Also, the use of a "non-ionic contrast agent" may have a lower risk of allergic response. Radiation exposure from an IVP is relatively low. This is because a fetus should not be exposed to any radiation, if possible. This web site has been optimized for user experience and security, therefore Internet Explorer IE is not a recommended browser. Thank you. It can find: Kidney stones Enlarged prostate Tumors in the kidney, ureters or urinary bladder Scarring from urinary tract infection Birth defects of the urinary tract The dye shows up well on the x-ray and outlines your organs.

It would be used to check: Side and low back pain Blood in the urine hematuria Kidney stone -related symptoms IVP isn't used as much today, but it's still sometimes helpful. In general, reactions are minor, and consist of: Feeling flushed a sudden, temporary reddening of the face, neck or chest Nausea Vomiting These are often treated with antihistamines drugs that reduce the histamines in your body from an allergic reaction.

In very rare cases, more severe reactions can occur. These can include: Breathing difficulties Low blood pressure Swelling of the mouth or throat Cardiac arrest Risk Factors Some people are more likely to react badly to the dye than others. Some risk factors include: History of allergic reactions such as hay fever, asthma or hives Congestive heart failure Diabetes In these cases, you may be given antihistamines or steroids before the exam.

More Information. Explore Further. The technologist will be able to hear and talk to you using a speaker and microphone. The traditional MRI unit is a large cylinder-shaped tube surrounded by a circular magnet. You will lie on a table that slides into a tunnel towards the center of the magnet. Some MRI units, called short-bore systems , are designed so that the magnet does not completely surround you.

Some newer MRI machines have a larger diameter bore, which can be more comfortable for larger patients or those with claustrophobia. They are especially helpful for examining larger patients or those with claustrophobia. Open MRI units can provide high quality images for many types of exams. Open MRI may not be used for certain exams. For more information, consult your radiologist.

CT scanning combines special x-ray equipment with sophisticated computers to produce multiple images or pictures of the inside of the body. These cross-sectional images of the area being studied can then be examined on a computer monitor, printed or transferred to a CD. In many ways, a CT scan works like other x-ray exams. Different body parts absorb x-rays in different amounts. This difference allows the doctor to distinguish body parts from one another on an x-ray or CT image.

A conventional x-ray exam directs a small amount of radiation through the body part under examination. A special electronic image recording plate captures the image.

Bones appear white on the x-ray. Soft tissue, such as the heart or liver, shows up in shades of gray. Air appears black.

With CT scanning, several x-ray beams and electronic x-ray detectors rotate around you. These measure the amount of radiation being absorbed throughout your body. Sometimes, the exam table will move during the scan. A special computer program processes this large volume of data to create two-dimensional cross-sectional images of your body. The system displays the images on a computer monitor.

CT imaging is sometimes compared to looking into a loaf of bread by cutting the loaf into thin slices. When the computer software reassembles the image slices, the result is a very detailed multidimensional view of the body's interior. Nearly all CT scanners can obtain multiple slices in a single rotation. These multi-slice multidetector CT scanners obtain thinner slices in less time.

This results in more detail. Modern CT scanners can image large sections of the body in just a few seconds, and even faster in small children. Such speed is beneficial for all patients. Speed is especially beneficial for children, the elderly, and critically ill — anyone who finds it difficult to stay still, even for the brief time necessary to obtain images.

For children, the radiologist will adjust the CT scanner technique to their size and the area of interest to reduce the radiation dose. MRI uses a powerful magnetic field, radiofrequency pulses and a computer to produce detailed pictures of organs, soft tissues, bone and virtually all other internal body structures. The images can then be examined on a computer monitor, transmitted electronically, printed or copied to a CD. MRI does not use ionizing radiation x-rays.

Instead, radio waves re-align hydrogen atoms that naturally exist within the body. This does not cause any chemical changes in the tissues.

As the hydrogen atoms return to their usual alignment, they emit different amounts of energy depending on the type of tissue they are in. The scanner captures this energy and creates a picture using this information. In most MRI units, the magnetic field is produced by passing an electric current through wire coils. Other coils are inside the machine and, in some cases, are placed around the part of the body being imaged. These coils send and receive radio waves, producing signals that are detected by the machine.

The electric current does not come into contact with the patient. A computer processes the signals and creates a series of images, each of which shows a thin slice of the body. The radiologist can study these images from different angles. MRI is often able to tell the difference between diseased tissue and normal tissue better than x-ray, CT, and ultrasound. If CT urography is being performed, the technologist will begin by positioning you on the CT examination table, usually lying flat on your back or possibly on your side or stomach.

You may be asked to change positions during portions of the examination. Straps and pillows may be used to help you maintain the correct position and to hold still during the exam. Many scanners are fast enough to scan children without sedation. In special cases, children who cannot hold still may need sedation. Motion may cause blurring of the images and degrade image quality the same way that it affects photographs.

If contrast material is used, a nurse or technologist will inject the contrast through an IV line placed in the hand or arm. Next, the table will move quickly through the scanner to determine the correct starting position for the scans. Then, the table will move slowly through the machine for the actual CT scan. Depending on the type of CT scan, the machine may make several passes. The technologist may ask you to hold your breath during the scanning.

Any motion, including breathing and body movements, can lead to artifacts on the images. This loss of image quality can resemble the blurring seen on a photograph taken of a moving object. When the exam is complete, the technologist will ask you to wait until they verify that the images are of high enough quality for accurate interpretation by the radiologist.

CT exams are generally painless, fast, and easy. Multidetector CT reduces the amount of time that the patient needs to lie still. If MR urography is being performed, the technologist will begin by positioning you on the MRI examination table, usually lying flat on your back or possibly on your side or stomach. Straps and bolsters may be used to help you maintain the correct position and to hold still during imaging.

The technologist may place devices that contain coils capable of sending and receiving radio waves around or next to the area of the body under examination.

MRI exams generally include multiple runs sequences , some of which may last several minutes. Each run will create a different set of noises. If a contrast material will be used in the MRI exam, a nurse or technologist will insert an intravenous IV line into a vein in your hand or arm. You will be moved into the magnet of the MRI unit, and the radiologist and technologist will leave the room while the MRI examination is performed. When the exam is complete, the technologist may ask you to wait while the radiologist checks the images in case more are needed.

The technologist will remove your IV line after the exam is over and place a small dressing over the insertion site. If the exam uses iodinated contrast material, your doctor will screen you for chronic or acute kidney disease. The doctor may administer contrast material intravenously by vein , so you will feel a pin prick when the nurse inserts the needle into your vein.

You may feel warm or flushed as the contrast is injected. You also may have a metallic taste in your mouth. This will pass. You may feel a need to urinate. However, these are only side effects of the contrast injection, and they subside quickly.

When you enter the CT scanner, you may see special light lines projected onto your body. These lines help ensure that you are in the correct position on the exam table. With modern CT scanners, you may hear slight buzzing, clicking and whirring sounds. These occur as the CT scanner's internal parts, not usually visible to you, revolve around you during the imaging process.

You will be alone in the exam room during the CT scan, unless there are special circumstances. For example, sometimes a parent wearing a lead shield may stay in the room with their child. However, the technologist will always be able to see, hear and speak with you through a built-in intercom system. With pediatric patients, a parent may be allowed in the room but may need to wear a lead apron to minimize radiation exposure.

After a CT exam, the technologist will remove your intravenous line. They will cover the tiny hole made by the needle with a small dressing. You can return to your normal activities immediately. It is normal for the area of your body being imaged to feel slightly warm. If it bothers you, tell the radiologist or technologist. It is important that you remain perfectly still while the images are being taken.

This is typically only a few seconds to a few minutes at a time. You will know when images are being recorded because you will hear and feel loud tapping or thumping sounds. The coils that generate the radio waves make these sounds when they are activated. You will be provided with earplugs or headphones to reduce the noise made by the scanner. You may be able to relax between imaging sequences. However, you will need to keep the same position as much as possible without moving.

You will usually be alone in the exam room. However, the technologist will be able to see, hear, and speak with you at all times using a two-way intercom. Many facilities allow a friend or parent to stay in the room if they have also been screened for safety. Children will be given appropriately sized earplugs or headphones during the exam. Music may be played through the headphones to help pass the time.

MRI scanners are air-conditioned and well-lit. In some cases, IV injection of contrast material may be given before the images are obtained. The IV needle may cause you some discomfort and you may experience some bruising.

There is also a very small chance of skin irritation at the site of the IV tube insertion. Some patients may have a temporary metallic taste in their mouth after the contrast injection. If you do not require sedation, no recovery period is necessary. You may resume your usual activities and normal diet immediately after the exam. On very rare occasions, a few patients experience side effects from the contrast material.

These may include nausea, headache, and pain at the site of injection. It is very rare that patients experience hives, itchy eyes, or other allergic reactions to the contrast material.

If you have allergic symptoms, tell the technologist. A radiologist or other doctor will be available for immediate assistance. A radiologist , a doctor specially trained to supervise and interpret radiology exams, will analyze the images. The radiologist will send an official report to the doctor who ordered the exam. A person who is very large may not fit into the opening of a conventional CT scanner. Or, they may be over the weight limit—usually pounds—for the moving table.

High-quality images depend on your ability to remain perfectly still and follow breath-holding instructions while the images are being recorded. If you are anxious, confused or in severe pain, you may find it difficult to lie still during imaging. A person who is very large may not fit into certain types of MRI machines. There are weight limits on the scanners. Implants and other metallic objects can make it difficult to obtain clear images. Patient movement can have the same effect.

A very irregular heartbeat may affect the quality of images. This is because some techniques time the imaging based on the electrical activity of the heart. MRI may not always distinguish between cancer tissue and fluid, known as edema. An MRI exam typically costs more and may take more time than other imaging exams. Talk to your insurance provider if you have concerns about the cost of MRI. Please type your comment or suggestion into the text box below. Note: we are unable to answer specific questions or offer individual medical advice or opinions.

Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content.