MR myelography for identification of spinal CSF leak in spontaneous intracranial hypotension

Abstract

Background and purpose: CT myelography has historically been the test of choice for localization of CSF fistula in patients with spontaneous intracranial hypotension. This study evaluates the additional benefits of intrathecal gadolinium MR myelography in the detection of CSF leak.

Materials and methods: We performed a retrospective review of patients with spontaneous intracranial hypotension who underwent CT myelography followed by intrathecal gadolinium MR myelography. All patients received intrathecal iodine and off-label gadolinium-based contrast followed by immediate CT myelography and subsequent intrathecal gadolinium MR myelography with multiplanar T1 fat-suppressed sequences. CT myelography and intrathecal gadolinium MR myelography images were reviewed by an experienced neuroradiologist to determine the presence of CSF leak. Patient records were reviewed for demographic data and adverse events following the procedure.

Results: Twenty-four patients met both imaging and clinical criteria for spontaneous intracranial hypotension and underwent CT myelography followed by intrathecal gadolinium MR myelography. In 3/24 patients (13%), a CSF leak was demonstrated on both CT myelography and intrathecal gadolinium MR myelography, and in 9/24 patients (38%), a CSF leak was seen on intrathecal gadolinium MR myelography (P = .011). Four of 6 leaks identified independently by intrathecal gadolinium MR myelography related to meningeal diverticula. CT myelography did not identify any leaks independently. There were no reported adverse events.

Conclusions: Present data demonstrate a higher rate of leak detection with intrathecal gadolinium MR myelography when investigating CSF leaks in our cohort of patients with spontaneous intracranial hypotension. Although intrathecal gadolinium is an FDA off-label use, all patients tolerated the medication without evidence of complications. Our data suggest that intrathecal gadolinium MR myelography is a well-tolerated examination with significant benefit in the evaluation of CSF leak, particularly for patients with leak related to meningeal diverticula.

Fig 1.

Bar graph illustrating the rate of leak detection by CTM and MRM. A statistically significant difference was observed between CTM and MRM by a 2-tailed paired t test (P = .011).

Fig 2.

Patient 4. A 52-year-old former fire fighter with a 1-year history of postural headaches. Axial CTM (A and C) and axial T1 fat-suppressed images from MRM (B and D) following intrathecal administration of iodinated contrast and gadolinium. Multiple spinal diverticula are seen along with an extradural contrast collection (arrows, B) not evident on a concurrent CTM examination.

Fig 3.

Patient 2. A 62-year-old man with headache and recurrent subdural hemorrhage following evacuation, found to have imaging findings of SIH. Axial CTM (A) and MRM (B) images at the T9–T10 level. Spinal diverticula are evident on both examinations. The MRM demonstrates an extra-arachnoid contrast collection and ill-defined increased T1 signal surrounding the enlarged right spinal diverticula. Subsequent CT performed for epidural blood patch planning with a localization grid in place (C) shows the spinal diverticula; the extra-arachnoid contrast collection is not evident. The patient reported symptomatic relief following directed blood patch and was without headache as of the 2-month follow-up note.

Fig 4.

Patient 7. A 55-year-old man with a history of lethargy, fatigue, and hearing loss. Axial CTM (A and C) and axial MRM (B and D) images. CT shows bilateral spinal diverticula. MR image demonstrates prominent contrast leakage from the right-sided T5–T6 (B) and left T10–T11 (D) diverticula, with gadolinium extending into the adjacent paraspinal musculature. The patient underwent targeted epidural blood patches of both leaking spinal diverticula.

Fig 5.

Patient 8. A 55-year-old man with postural headache and low CSF pressure on lumbar puncture. Axial CTM (A), axial MRM (B), and coronal MRM (C) images. Coronal MRM shows multiple spinal diverticula. However, only the right T7–T8 spinal diverticula, seen on the CTM (A), shows evidence of contrast leakage on axial MRM (B), evident by ill-defined T1 shortening surrounding the cyst. This lesion was treated with directed epidural blood patch with symptomatic improvement for 5 years following treatment.