Epidural Contrast Volume on Post-Myelogram Lumbar CT Predicts the Rate of Subsequent Blood Patch Treatment.

BACKGROUND AND PURPOSE: Headaches due to cerebrospinal fluid (CSF) leakage are a well-known complication of dural puncture. The purpose of this study was to determine whether the presence and volume of epidural contrast on postmyelogram CTs of the lumbar spine were associated with post-dural puncture headaches (PDPHs) requiring epidural blood patch (EBP) treatment. METHODS: A retrospective case control study of all fluoroscopically guided lumbar myelograms performed over a 5-year period by a single radiology practitioner assistant was performed. Ten patients who underwent EBP treatment after their myelograms were identified. Forty-six patients with similar demographics who did not receive blood patches were then selected. CT-lumbar myelogram images of patients and controls were reviewed. The volume of epidural contrast was then quantified as "severe" or "mild." Severe epidural contrast was defined as contrast detected in the ventral epidural space, the extra-foraminal space, or extending greater than or equal to the length of two vertebral bodies from the level of dural puncture. RESULTS: Some amount of epidural contrast was seen in all patients. However, a severe volume of epidural contrast was associated with increased risk for PDPH requiring an EBP (odds ratio = 37.00; 95% CI = 4.1-330.8, p = 0.0012). CONCLUSION: Severe epidural contrast on postmyelogram CTs of the lumbar spine was associated with an increased risk of PDPH requiring EBP treatment. When present, this finding can alert the proceduralist that the patient may require closer observation and follow up with earlier intervention.

JOURNAL CLUB: Incidence of Complications Following Fluoroscopically Guided Lumbar Punctures and Myelograms.

OBJECTIVE: Headaches due to CSF leak are a well-described complication of dural puncture. It is uncertain how long patients should be observed after dural puncture to reduce the risk of headache. Most of the literature has focused on dural punctures performed without fluoroscopic guidance. The purpose of this study was to determine the incidence of complications from fluoroscopically guided dural punctures, with attention to predictive factors such as the length of bed rest after the procedure. MATERIALS AND METHODS: We retrospectively reviewed 2141 fluoroscopically guided dural punctures performed over a 5-year period by a single radiology practitioner assistant. All patients were contacted 48-72 hours after the procedure to assess for complications. Complications were categorized according to whether the patient reported having severe headache (requiring epidural blood patch for treatment), any headache, or any complaint. Using a multivariate logistic regression model, we assessed several possible predictors of complication: patient age, patient sex, needle caliber, puncture site, distance driven after recovery, length of postprocedural bed rest, contrast concentration, and contrast volume. RESULTS: In all, 0.8% of patients reported having a severe headache, 2.2% reported having any headache, and 2.6% reported having any complaint. In the multivariate analysis, age and sex were predictive of complication rates (with younger women having higher rates), but the other variables were not predictive. In particular, length of postprocedural bed rest showed statistical equivalence. CONCLUSION: Fluoroscopically guided dural punctures result in few complications compared with lumbar punctures performed without fluoroscopic guidance. Postprocedural bed rest greater than 2 hours does not reduce complication rates for fluoroscopically guided lumbar punctures.