Modified Ultrafast Dynamic CT Myelography: Method, Outcomes, and Comparison With Noninvasive Imaging

Spontaneous intracranial hypotension (SIH) is primarily caused by cerebrospinal fluid (CSF) leakage; however, precise localization of the leakage remains challenging. This study evaluated the outcomes of ultrafast CT myelography in Korea.

Data were prospectively collected from patients with SIH who underwent ultrafast CT myelography at Seoul National University Hospital between August 2023 and December 2024. Success rates and leakage sites were documented. We also examined whether the most prominent lateral extradural fluid collection observed on heavily T2-weighted magnetic resonance (MR) myelography could predict the actual leak site identified by ultrafast CT myelography.

Fifty-one patients (22 males and 29 females) underwent ultrafast CT myelography, with a mean age of 42.9±10.3 years (range, 25-70 years). Technical success rate was 90.2% (46/51). Leakage sites were identified in 44 patients (95.7%) of the 46 with successful examinations. Among these 44 patients, 4 (9.1%) demonstrated spinal cord herniation at the dural defect site. The leak site was cervical in 2 patients (5.0%) and thoracic in 38 patients (95.0%): 28 at the upper, 8 at the mid, and 2 at the lower thoracic levels. Among the 40 patients with visible leakage, only 5 (12.5%) had exact concordance between the leakage site and the most prominent lateral extradural fluid collection seen on pre-procedural MR myelography.

The upper thoracic level was the most common site of CSF leakage, which differed from assumptions based on noninvasive spine MR myelography or non-contrast spine CT.