Critical Assessment of Myelography Practices: A Call for Rational Guideline Revision

Abstract

BACKGROUND AND PURPOSE: Patient preparation for myelography and postprocedural monitoring varies widely between practices, despite published guidelines. Our aim was to examine the current practice variations in discontinuing reportedly seizure thresholdlowering medications before myelography and to assess the reported incidence of postmyelographic seizures. MATERIALS AND METHODS: An e-mail survey was sent to American Society of Neuroradiology members concerning the number of postmyelographic seizures experienced in the past 5 years, the presence of an institutional policy for discontinuing seizure threshold-lowering medications, and the type of myelographic contrast used. We compared the postmyelographic seizure frequency in the responses. RESULTS: Of 700 survey responses, 57% reported that they do not discontinue seizure threshold-lowering medications before myelography. Most (97%) indicated never having a patient experience a seizure following myelography. The number of postmyelographic seizures between those who discontinue seizure threshold-lowering medications and those who do not was not statistically significant (OR ϭ 2.13; 95% CI, 0.91-4.98; P ϭ .08). Most (95%) reported using nonionic hypo-osmolar agents. CONCLUSIONS: Survey results revealed widely variable practices for patient myelography preparation and postprocedural monitoring. We found no difference in reported seizures between those who discontinued seizure threshold-lowering medications and those who did not. In light of our findings, we propose that discontinuing reportedly seizure threshold-lowering medications is not warranted with the current nonionic water-soluble contrast agents and may be potentially harmful in some instances. This work supports revision of existing recommendations to withhold such medications before myelography.

Safety of Consecutive Bilateral Decubitus Digital Subtraction Myelography in Patients with Spontaneous Intracranial Hypotension and Occult CSF Leak

“…23 Also, we did not routinely screen for seizure-threshold-lowering medications before performing the procedures, a practice that may further reduce the risk of seizures. 27 Most interesting, a statistically significant correlation was noted between the volume of intrathecal injectate and transient minor neurologic effects such as vertigo, syncope, altered mental status, and autonomic dysfunction. Specifically, variable amounts of saline injectate were sometimes used to prepressurize the thecal sac in these patients with chronically low CSF volume, which may have resulted in vasovagal reactions or mechanical effects on pain-sensitive nerves and vessels related to CSF pressurization.…”

It Is Not Necessary to Discontinue Seizure Threshold–Lowering Medications Prior to Myelography

“…In a 2018 survey of 700 American Society of Neuroradiology members, only 43% of respondents reported screening for STLMs. 10 A mere 3% reported having had a patient experience a postprocedural seizure during their entire personal history of clinical myelography practice. There was no statistically significant difference in postmyelographic seizures between practices that discontinued STLMs and those that did not.…”

“…9 In 2018, only 43% of practitioners screened for such medications. 10 Decreased adherence to these recommendations is likely attributable to increased familiarity with the newer contrast agents. Furthermore, Ͼ100 medications fall into the category of STLMs.…”

The Role and Contribution of Lumbar Myelography in the Diagnosis and Treatment of Patients With Lumbar Degenerative Disorders: Clinical and Statistical Evaluation of Post-Myelography Treatment of 63 Patients

“…Myelography is an imaging technique performed by providing a contrast material to the intrathecal region to display the pathologies in the spinal canal and its contents. It uses a real-time form of X-ray called fluoroscopy and an injection of contrast material to evaluate the spinal cord, nerve roots, and meninges [1]. This diagnostic method has been developed gradually over 90 years.…”