Diagnostic Yield of CT Myelography for the Identification of CSF Leaks in Patients with Post Dural Puncture Headache.

BACKGROUND AND PURPOSE: Post dural puncture headache (PDPH) refractory to conservative measures can be clinically debilitating, and diagnostic evaluation with spinal imaging including CT myelography (CTM) may be performed to localize a CSF leak and guide treatment. The purpose of this study is to determine the diagnostic yield of CTM for detecting a CSF leak in patients with persistent PDPH.

MATERIALS AND METHODS: This is a single-center, retrospective cohort study of patients referred for CTM between September 2013 and August 2025 to localize and/or identify a CSF leak in patients with PDPH. Brain MRIs were categorized as either positive or negative for findings of intracranial hypotension. CTMs were categorized as either positive or negative for the presence of a CSF leak or arachnoid bleb. The overall rate of CTM positivity in patients with PDPH was calculated. Logistic regression analysis was used to investigate variables that were associated with positive CTM.

RESULTS: A total of 118 patients with PDPH were included in the analysis (81% women, mean age of 40 ± 12 years). Brain MRIs were negative for findings of intracranial hypotension in 92% of cases. Overall, CTM was positive in only 7 cases (5.9%, 7/118). Four were extradural fluid collections consistent with a CSF leak, and 3 were arachnoid blebs at the site of prior dural puncture. In 3 positive cases where both spine MRI and CTM were available, the abnormality was also seen on MRI in 2 cases. On logistic regression, only a positive brain MRI was independently associated with a significantly higher odds of a positive CTM (OR: 12.6 [95% CI, 1.8-90]; P = .012).

CONCLUSIONS: CTM has a low diagnostic yield in patients with PDPH, uncommonly identifying specific leak related findings. Because CTM necessarily involves repeat dural puncture, and given this low yield, it should be used sparingly in patients with refractory PDPH, especially when signs of intracranial hypotension are absent on brain MRI. As some findings on CTM are also seen on spinal MRI, which is noninvasive, further research is needed to compare the yield of MRI and CTM to determine whether and when CTM provides additional diagnostic information in this population.