Spinal discography is a diagnostic procedure that is used to link back or neck pain to a suspected disc pathology in the spinal column. The other common name for this minimally invasive operation is discogram. Discography consists of 2 distinct components of testing. The first is used to measure pain response from direct patient feedback, when the disc is pressurized. The second facet of the test allows visualization of the intervertebral structure from the inside, since contrast dye is injected into the nucleus pulposus during the procedure.
Discograms were once far more commonplace than they are today, since more recent medical opinion has begun to swing against general use of the technique. However, many patients still undergo the test for instances of suspected painful spinal discs that can not be otherwise confirmed as the source of symptoms through alternate means.
This dissertation examines the nature of spinal discography testing, including the way the examination is performed, the risk factors involved and the important considerations that candidate patients must understand before undergoing the procedure.
Discograms are tests that are utilized in an attempt to relate pain to a suspected intervertebral source. The test can be used in cases of intervertebral bulging, herniation, rupture or desiccation. The success rate of the test remains virtually the same regardless of what type of suspected pathology exists in the disc structure.
Discograms utilize minimally invasive technology to inject fluid and contrast dye into the disc nucleus. In most instances, more than one disc will be injected, with typical tests involving 1 to 4 spinal spacers in total.
By adding interior pressure and volume to the spinal disc, doctors hope to determine if the disc will respond with pain, thereby theoretically identifying the structure as the source of ongoing back or neck pain.
Additionally, the contrast dye allows the physician to image the disc from the inside, potentially helping to identify any annular tears or leaking disc nucleus material that might be responsible for causing pain through the processes of neurological compression or chemical irritation.
Discograms are usually used when a known herniation or degeneration exists, but has not been verified as the origin of the symptomatic expression, due to a lack of correlation to a central or foraminal stenosis event, or to a chemical radiculitis condition.
The discogram technique is relatively simple and is performed as an outpatient procedure under limited local anesthetic. The entire procedure will be performed using the assistance of fluoroscopy, which is a form of live image x-ray technology.
First, the physician will administer a local anesthetic to the skin and subdermally, on the path towards the discs to be tested. Once anesthetized, a smaller needle will be introduced directly into the selected spinal discs. Typically all needles will first be placed into each disc to be tested before any are pressurized, but this is not an absolute rule.
Next, fluid will be introduced into the disc center through a syringe attached to the needle. The patient will be asked to provide a description of their feelings during this time. The most typical responses include no feeling, pressure or pain. If pain is noted, the doctor will inquire if this discomfort mirrors the existing symptomatic complaint or whether the symptom is new and unfamiliar.
Once the test is complete, the area will be imaged using x-ray or CT scan to monitor the spread and path taken by the contrast dye inside the disc. This can be very helpful in determining if any of the fluid leaks out through the outer wall, potentially identifying an annular tear condition.
There is little aftercare required, but the patient is usually advised to rest for a few days and to keep the area clean and sanitary. Antibiotics may be prescribed after the test, but most patients are provided oral versions in advance of the procedure, as well as hooked-up to intravenous antibiotics during the minimally-invasive operation itself.
Discograms are really very low-tech tests. However, they do enjoy the benefit of direct patient feedback, which helps them to provide somewhat enlightened results. Discography is very useful for discovering otherwise unseen annular tears and might even help to trace the path of irritating nucleus proteins onto sensitive neurological fibers. However, these benefits come at a rather large expense, since there are also many, many negative connotations to the discogram procedure.
One of the main downsides to the test is that is really shows little efficacy for discovering the existing cause of pain. The test is usually used regionally, when more than one disc might be the cause of the symptomology. This means that various discs already show marked herniation and/or degeneration. Internally stressing any of these discs is likely to produce pain, causing false positive results in countless patients each year.
Another terrible negative consequence of discography is that it is usually used to convince a patient to undergo surgical correction of the disc abnormality. Herniated disc surgery demonstrates abysmal curative results.
Since the tested and "confirmed" disc may or may not be the true source of existing pain, the procedure might not even be targeting the actual culprit. This fact goes a long way in explaining why so few postoperative patients enjoy lasting cures following discogram "verification" of pain-inducing pathology.
Discograms are inherently dangerous themselves. The procedure is often cited as being unbearably painful and sometimes results in a markedly increased pain expression that lasts for months or years after the test. In some instances, the test itself can permanently damage a disc, causing it to tear or rupture, when it may have been innocent of enacting any painful stimuli before the procedure.
Furthermore, the test is occasionally the cause of spinal nerve damage or cerebral spinal fluids leaks. The latter consequence might require a secondary follow-up operation to correct, if the leak does not abate by itself.
However, the worst possible collateral consequence of discography is the possibility of discal infection. Discitis is a very serious and difficult to resolve type of infection that can main or kill. While discitis is not common in the general population, discograms increase the risk of suffering this type of infection considerably and can greatly raise the likelihood of discal contamination is particular patient demographics.
The current trend away from discography is rather prevalent, since more doctors recognize the risks and inherent diagnostic weaknesses of the test. However, since the procedure is a real money-maker and can help convince patients towards high ticket services, such as discectomy and spinal fusion, the test remains a mainstay in the arsenal of medical business, rather than medical science.