MRI myelography for diagnosis and targeted blood patching of multilevel thoracic spine CSF leaks: Report of 2 cases

Abstract

In patients with occult cerebrospinal fluid (CSF) leaks or CSF leak syndrome, orthostatic headaches are a common presenting symptom. Although computed tomography (CT) myelography has historically been the gold standard for diagnosis with radioisotope cisternography as a diagnostic alternative, magnetic resonance imaging (MRI) myelography using intrathecal gadolinium has reported sensitivity of 80%-87%. Two patients with spontaneous orthostatic headaches lasting for several days were diagnosed with CSF leaks at multiple thoracic segments using MRI myelogram with intrathecal gadolinium (Gadavist, Bayer, Whippany, NJ). This allowed for subsequent targeted treatment with CT fluoroscopy guidance, resulting in therapeutic responses within 1-2 treatment with targeted blood patching. Although intrathecal gadolinium is an off-label use, the superior contrast resolution and lack of radiation exposure makes MRI myelography an excellent imaging modality for diagnosing CSF leak, targeting treatment, and monitoring outcomes compared to CT myelography and radioisotope cisternography.

Keywords: Blood patch; CSF leak; MR myelogram.

Fig. 1

A. Indirect signs of intracranial hypotension on MRI. (a) T2W brain MRI showing bilateral prominent subdural effusion. (b) T1W brain MRI with IV contrast showing pachymeningeal enhancement. (c) T2W sagittal thoracic MRI showing extradural fluid collections tracking posteriorly. (d) T2W axial thoracic MRI showing extradural fluid collection along the posterior thecal sac. B. MR myelogram with intrathecal gadolinium. (e) Axial views show CSF leaking into the posterior spinal epidural space at T4-T8. (f) CSF tracking and exiting the bilateral neural foramina. C. CT fluoroscopy-guided needle placement for blood patching. (g and h) Transforaminal and (i) translaminal approach at multiple thoracic levels. Preblood patch contrast injection demonstrates the distribution of contrast in the epidural space.

Fig. 2

A. Indirect signs of intracranial hypotension on MRI. (a) T2W brain MRI shows a possible trace subdural effusion in the frontal lobes. (b) T1W brain MRI with IV contrast demonstrates normal lack of pachymeningeal enhancement. (c) T2W sagittal thoracic MRI showing extradural fluid collections tracking posteriorly. (d) T2W axial thoracic MRI showing extradural fluid collection along the posterior thecal sac. B. MR myelogram with intrathecal gadolinium. (e) Axial view shows irregularity of the dural covering with CSF leaking into the posterior spinal epidural space and exiting the left neural foramen. C. Resolution of CSF leak after targeted blood patching. (f) T2 FRFSE axial image shows fluid in the posterior epidural space. (g) T1 with intrathecal gadolinium contrast showing a break in the posterior dura and CSF tracking along the posterior epidural space and exiting the bilateral foramina. (h) T2 FRFSE after blood patching showing absence of epidural fluid, the resolution of CSF leak.