Myelography as a stand-alone diagnostic procedure for degenerative spine disease in developing nations.

The use of "stand-alone" contrast myelography (i.e., without computed tomography) has a proven track record in developing nations where few patients have access to magnetic resonance imaging, whether on the basis of prohibitive cost or the absence of such a modality altogether. To substantiate the author's 12-year experience with more than 300 myelograms performed in 16 different countries (plus some 1500 studies during 30 years of practice in the United States), a prospective pilot study was undertaken over 1 month in a community-based neurosurgical setting in western Kenya. Forty patients underwent cervical or lumbar myelography at Tenwek Hospital under the auspices of the Neurosurgery Training Program for East, Central, and South Africa (NSTP-ECSA) following failure of conservative measures to treat spine-related pathology. Thirty-five of the forty patients (88%) came to definitive surgery on the basis of a positive study that correlated with their clinical history and physical examination. There were no significant complications from the procedures, and no false-positive studies, with virtually all patients returning to normal activity and/or gainful employment within 3 weeks of their surgery. Myelography as a stand-alone diagnostic procedure is a sensitive, specific, and cost-effective means of diagnosing symptomatic degenerative spine disorders. Accordingly, its use should be encouraged at every NSTP-ECSA training site to address such ubiquitous pathology.

Lumbar discography.

Lumbar discography has generally proven to be a safe diagnostic tool for the evaluation and potential treatment planning of presumed discogenic pain, but it has not been wholeheartedly embraced by the radiologic and surgical community because of doubts as to its safety, accuracy, and relevance to patient outcome. There have been some conflicting reports on the relative merits and limitations of the procedure in the diagnosis and treatment planning of low back pain and radiculopathy; further studies are needed to determine with certainty whether discography is in fact able to localize the precise discs of clinical significance and accurately predict those patients who will respond well to surgery and those who will not.

Brachial plexus injury: clinical manifestations, conventional imaging findings, and the latest imaging techniques.

Brachial plexus injury (BPI) is a severe neurologic injury that causes functional impairment of the affected upper limb. Imaging studies play an essential role in differentiating between preganglionic and postganglionic injuries, a distinction that is crucial for optimal treatment planning. Findings at standard myelography, computed tomographic (CT) myelography, and conventional magnetic resonance (MR) imaging help determine the location and severity of injuries. MR imaging sometimes demonstrates signal intensity changes in the spinal cord, and enhancement of nerve roots and paraspinal muscles at MR imaging indicates the presence of root avulsion injuries. New techniques including MR myelography, diffusion-weighted neurography, and Bezier surface reformation can also be useful in the evaluation and management of BPI. MR myelography with state-of-the-art technology yields remarkably high-quality images, although it cannot replace CT myelography entirely. Diffusion-weighted neurography is a cutting-edge technique for visualizing postganglionic nerve roots. Bezier surface reformation allows the depiction of entire intradural nerve roots on a single image. CT myelography appears to be the preferred initial imaging modality, with standard myelography and contrast material-enhanced MR imaging being recommended as additional studies. Work-up will vary depending on the equipment used, the management policy of peripheral nerve surgeons, and, most important, the individual patient.

Shift in imaging modalities of the spine through 25 years and its impact on patient ionizing radiation doses.

STUDY DESIGN: Retrospective. OBJECTIVE: To explore the shift in modalities when diagnosing the spine in the years 1979-2003. To see how this shift, together with a radiation protective policy, have influenced on the ionizing radiation doses. SUMMARY OF BACKGROUND DATA: The shift from CT/myelography to MR when diagnosing the spine is well known. To what extent this has changed the radiation doses has to our knowledge not yet been published. METHODS: Activity reports from a department of radiology have been reviewed. Relevant radiation doses estimates have been obtained from the Norwegian Radiation Protection Authority. RESULTS: MRI was introduced in 1992 and has been used increasingly since then. Conventional X-ray to the spine has been practically unchanged. Myelography and CT decreased markedly after the introduction of MRI. The total number of examinations of the spine has increased, but the radiation doses given have decreased since 1993. CONCLUSIONS: The introduction of MRI together with a radiation protective policy have reduced the ionizing radiation doses given to this population, in spite of an increase in the total number of examinations of the spine.

Use trends and geographic variation in neuroimaging: nationwide medicare data for 1993 and 1998.

BACKGROUND AND PURPOSE: Powerful tools, including CT and MR imaging, have revolutionized neuroimaging. These are routinely used, but the extent and variation of use has not been studied. Our purposes were to determine the use rates of MR imaging and CT (of spine, brain, or head and neck), myelography, conventional angiography, and MR angiography in diagnosing neurologic disorders; to study trends in use; and to determine regional variations in use. METHODS: We used the National Part B Medicare Database for 1993 and 1998 to compare rates of use for these procedures in 10 geographic regions. RESULTS: In 1993 and 1998, respectively, 13,897 and 19,431 (39.8% increase) neuroimaging procedures were performed per 100,000 Medicare beneficiaries nationwide. Use of brain or head and neck CT (30.4%) and MR imaging (43.6%), spinal CT (3.5%) and MR imaging (83.0%), myelography (56.6%), and conventional angiography (24.3%) increased in 1998 versus 1993. Increases in MR angiography were not assessed, because this procedure was not reimbursable in 1993. Regional use of brain or head and neck and spinal CT and MR studies varied considerably; ratios of highest and lowest rates were 1.38-1.56. Use of MR angiography, myelography, and conventional angiography varied three- to fourfold. CONCLUSION: Use of MR and CT studies of the brain or head and neck and of the spine increased considerably in the Medicare population between 1993 and 1998. Use of conventional invasive procedures such as myelography and angiography increased strikingly, contrary to the expected decline. Regional use varied substantially.

Long term effects of the introduction of noninvasive investigations in neuroradiology. Part 1: Overall trends.

A 25 year retrospective survey of requests for imaging studies in a neurological hospital showed that the introduction of radionuclide scanning service had a relatively minor effect on the demand for other investigations. The introduction of computed tomography ten years later had a profound and continuing effect on not only the pattern and volume of requests for imaging, but also on inpatient discharges and outpatient attendances.

[Effect of new imaging procedures on conventional roentgen diagnostic methods]. / Einfluss neuer bildgebender Verfahren auf bekannte röntgendiagnostische Methoden.

The diagnostic radiology workload of a general hospital served as basis to assess the statistical distribution of various diagnostic radiology methods and the inroads made by new imaging methods on the conventional ones: CT, DAS, sonography and endoscopy. In particular, the statistical breakdown shows how these methods have been applied in examining the gastrointestinal tract, the kidneys, the gallbladder and biliary tract, and how they have influenced the frequency rate of special examination methods such as angiography and myelography. Statistic assessment of the results obtained during the past ten years shows an increasing predominance of less invasive examination methods and increasing use of endoscopic methods for examining the gastrointestinal tract, the sum total of examinations remaining approximately the same throughout.