T.i Discography

[Twyla Plack]

Discography is the study and cataloging of published sound recordings, often by specified artists or within identified music genres. The exact information included varies depending on the type and scope of the discography, but a discography entry for a specific recording will often list such details as the names of the artists involved, the time and place of the recording, the title of the piece performed, release dates, chart positions, and sales figures.[1]

A discography can also refer to the recordings catalogue of an individual artist, group, or orchestra. This is distinct from a sessionography, which is a catalogue of recording sessions, rather than a catalogue of the records, in whatever medium, that are made from those recordings. The two are sometimes confused, especially in jazz, as specific release dates for jazz records are often difficult to ascertain, and session dates are substituted as a means of organizing an artist's catalogue.

Another, more recent, definition of discography refers to a collection of musical recordings by a performer or composer, considered as a body of work. For instance, all studio albums by a performer could collectively be considered their discography.

The term "discography" was popularized in the 1930s by collectors of jazz records, i.e. 'to study and write about the discs of music'. Jazz fans did research and self-published discographies about when jazz records were made and what musicians were on the records, as record companies did not commonly include that information on or with the records at that time. Two early jazz discographies were Rhythm on Record by Hilton Schleman and Hot Discography by Charles Delaunay.[1][3]

Each disc has a strong outer layer called an annulus and a center part, called a nucleus, made of a soft, rubber-like material. When discs bulge or rupture, they may press on the nerves of the spinal column and cause pain or weakness.

In a discogram, a contrast liquid is injected into the center of one or more spinal discs using x-ray guidance. This injection may temporarily reproduce the patient's back pain symptoms. As part of the procedure, an x-ray or CT scan also may be performed to obtain pictures of the injected disc.

A discogram is typically performed to help diagnose the cause of back pain and to guide the treatment of abnormal discs. The procedure also may be performed prior to surgery to help identify discs that need to be treated or removed.

Tell your doctor about all the medications you take, including herbal supplements. List any allergies, especially to local anesthetic, general anesthesia, or contrast materials. Your doctor may tell you to stop taking aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs) or blood thinners before your procedure.

Women should always tell their doctor and technologist if they are pregnant. Doctors will not perform many tests during pregnancy to avoid exposing the fetus to radiation. If an x-ray is necessary, the doctor will take precautions to minimize radiation exposure to the baby. See the Radiation Safety page for more information about pregnancy and x-rays.

This exam typically uses a radiographic table, one or two x-ray tubes, and a video monitor. Fluoroscopy converts x-rays into video images. Doctors use it to watch and guide procedures. The x-ray machine and a detector suspended over the exam table produce the video.

The CT scanner is typically a large, donut-shaped machine with a short tunnel in the center. You will lie on a narrow table that slides in and out of this short tunnel. Rotating around you, the x-ray tube and electronic x-ray detectors are located opposite each other in a ring, called a gantry. The computer workstation that processes the imaging information is in a separate control room. This is where the technologist operates the scanner and monitors your exam in direct visual contact. The technologist will be able to hear and talk to you using a speaker and microphone.

X-rays are a form of radiation like light or radio waves. X-rays pass through most objects, including the body. The technologist carefully aims the x-ray beam at the area of interest. The machine produces a small burst of radiation that passes through your body. The radiation records an image on photographic film or a special detector.

Different parts of the body absorb the x-rays in varying degrees. Dense bone absorbs much of the radiation while soft tissue (muscle, fat, and organs) allow more of the x-rays to pass through them. As a result, bones appear white on the x-ray, soft tissue shows up in shades of gray, and air appears black.

Fluoroscopy uses a continuous or pulsed x-ray beam to create images and project them onto a video monitor. Your exam may use a contrast material to clearly define the area of interest. Fluoroscopy allows your doctor to view joints or internal organs in motion. The exam also captures still images or movies and stores them electronically on a computer.

A nurse or technologist will insert an intravenous (IV) line into a vein in your hand or arm so that sedative medication can be given intravenously. You must be awake during the procedure in order to communicate any of the symptoms that you are experiencing during the test.

Guided by real-time x-ray images (fluoroscopy), the physician will insert a needle through your skin into the center of the disc being examined. Once the needle is inside the disc, a contrast material is injected and the needle is removed.

During the procedure you may be asked to describe your pain in terms of location, distribution and severity. If the injected disc is the source of your back pain, you may feel pain similar to what you experience on a day-to-day basis. The process may be repeated for additional discs. In order for the discogram to be considered an objective test, the operator cannot disclose what level is being injected and when the injection is taking place.

After the injections are complete, an x-ray or CT scan may be performed to further analyze the injected disc(s). When contrast material spreads outside a disc, it may indicate that there are fissures in the outer ring of the disc.

You will feel a slight pinch when the nurse inserts the needle into your vein for the IV line and when they inject the local anesthetic. Most of the sensation is at the skin incision site. The doctor will numb this area using local anesthetic. You may feel pressure when the doctor inserts the catheter into the vein or artery. However, you will not feel serious discomfort.

You may have some pain at the injection site for several hours after you go home. You may apply an ice pack to the area on and off for 20 minutes at a time. You may also take your usual pain medications as prescribed by your doctor. If the pain is severe and is associated with fever, then you should immediately see a physician.

A radiologist, a doctor trained to supervise and interpret radiology examinations, will analyze the images. The radiologist will send a signed report to your primary care or referring physician who will discuss the results with you.

You may need a follow-up exam. If so, your doctor will explain why. Sometimes a follow-up exam further evaluates a potential issue with more views or a special imaging technique. It may also see if there has been any change in an issue over time. Follow-up exams are often the best way to see if treatment is working or if a problem needs attention.

Doctors take special care during x-ray exams to use the lowest radiation dose possible while producing the best images for evaluation. National and international radiology protection organizations continually review and update the technique standards radiology professionals use.

Modern x-ray systems minimize stray (scatter) radiation by using controlled x-ray beams and dose control methods. This ensures that the areas of your body not being imaged receive minimal radiation exposure.

Because a discogram is an invasive test, it is not typically used for the initial evaluation of back pain. A discogram is usually recommended after conservative treatment, such as medication or physical therapy, over a period of four to six months fails to alleviate back pain. Because a disc can be damaged without causing pain, the results of a discogram are usually combined with other test results to determine a treatment plan.

In the majority of cases, plain radiographs, spine MRI or spine CT (when MRI cannot be performed) are the primary exams indicated for the diagnostic evaluation of lower back pain. Other tests, such as myelography or discography, are often used in some situations to address specific clinical questions prior to performing surgical procedures.

RadiologyInfo.org is not a medical facility. Please contact your physician with specific medical questions or for a referral to a radiologist or other physician. To locate a medical imaging or radiation oncology provider in your community, you can search the ACR-accredited facilities database.

This website does not provide cost information. The costs for specific medical imaging tests, treatments and procedures may vary by geographic region. Discuss the fees associated with your prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a better understanding of the possible charges you will incur.

Web page review process: This Web page is reviewed regularly by a physician with expertise in the medical area presented and is further reviewed by committees from the Radiological Society of North America (RSNA) and the American College of Radiology (ACR), comprising physicians with expertise in several radiologic areas.

Outside links: For the convenience of our users, RadiologyInfo.org provides links to relevant websites. RadiologyInfo.org, RSNA and ACR are not responsible for the content contained on the web pages found at these links.

A lumbar discogram, also called lumbar discography, is a minimally invasive, presurgical diagnostic test devised to determine if an intervertebral disc in the lower spine is the primary cause of back pain with or without leg pain (sciatica).1Peh W. Provocative discography: Current status. Biomed Imaging Interv J. 2005;1(1):e2. DOI:10.2349/biij.1.1.e2 Available from: