MR Myelography With Intrathecal Gadolinium Can Detect Subtle Postoperative CSF Leak Presentation Number EE-31 S. Hegde, G. Lagemann University of Pittsburgh Medical Center, Pittsburgh, PA

Disclosures: None

Purpose To report MR myelography's use in identifying a subtle postoperative cerebrospinal fluid (CSF) leak in a patient with previous Chiari I decompression. Prior CT myelogram had failed to identify the site of leak.

Case Report A 24-year-old female presented with persistent severe headaches following Chiari I decompression 2 years prior. A lumbar puncture revealed opening pressure of 0 cm H2O. An extensive work up included CT myelography to search for site of CSF leak.

Imaging Findings: CT Myelogram No site of CSF leak identified Abnormal convex contour to the dural graft along the margin of the suboccipital cranioplasty mesh

Case Report Magnetic resonance (MR) myelography was performed using 0.3 mL intrathecal MultiHance 529 mg/ml and subsequent multiplane T1 fat-saturated MR series targeting the spine and posterior cranial fossa.

Imaging Findings Prior CT myelography had failed to Axial T1 fat-saturated image following intrathecal administration of gadolinium demonstrates CSF leak from the left lateral margin of the patient’s suboccipital craniectomy and surgical mesh (arrow). Prior CT myelography had failed to Identify site of CSF leak

Operative Diagnosis Surgically-proven CSF leak at the left lateral margin of the cranioplasty mesh, as predicted on MR myelography.

Follow up 8 months after successful repair and resolution of symptoms, patient returned with recurrent headache and intracranial hypotension

Repeat MR Myelogram Axial T1 fat saturated images following repeat intrathecal administration of gadolinium show a new site of CSF leak along the posterior inferior margin of the dural graft (yellow arrow) and CSF accumulating outside the dural graft (red arrows)

Repeat MR Myelogram Coronal T1 fat saturated image following intrathecal administration of gadolinium demonstrates CSF accumulation outside the margins of the dural graft

Operative Findings At surgery, CSF was seen on the outside of the graft and the dural graft was thinned out in several areas A new graft was put after removal of the old graft At follow up patient’s symptoms had improved

Discussion Diagnosis of CSF leak is challenging and accurate detection is important for treatment planning Traditional techniques to detect CSF leak are: CT Myelography Digital Subtraction Myelography Radionuclide studies using Indium 111- DTPA Non-enhanced MRI MR myelography with intrathecal gadolinium is a recently-developed technique

Discussion: MR Myelography First described in humans in 2002 Only a few studies have been published to date evaluating spontaneous and post-traumatic leaks Intrathecal administration is usually performed with 0.5 mL gadolinium combined with 4-5 mL of saline, iohexol or CSF

Discussion: MR Myelography with Intrathecal Gadolinium MR myelography with intrathecal gadolinium has been shown to be more sensitive for slow flow or intermittent CSF leaks compared to CT myelography In some studies, MR myelography with intrathecal gadolinium detected CSF leak in 20% of patients for whom no leak was identified on CT myelography Aydin et had a sensitivity of 84% with gadolinium- enhanced MR cisternography for detection of CSF leak in patients with CSF rhinorrhea.

Discussion: MR Myelography for Detection of Postoperative CSF Leak This is the first report of MR myelography with intrathecal gadolinium successfully used to detect a postoperative CSF leak We use 0.3 mL of intrathecal Multihance 529 mg/mL In our case, CT myelography had failed to demonstrate the leak MR myelography twice successfully detected the site of CSF leak, both times confirmed at surgery

Conclusion MR myelography with intrathecal gadolinium can successfully detect subtle postoperative CSF leak

References Yoo HM, Kim SJ, Choi CG,et al. Detection of CSF leak in spinal CSF leak syndrome using MR myelography: correlation with radioisotope cisternography. AJNR Am J Neuroradiol. 2008;29:649-54. Chazen JL, Talbott JF, Lantos JE, Dillon WP. MR myelography for identification of spinal CSF leak in spontaneous intracranial hypotension. AJNR Am J Neuroradiol. 2014;35(10):2007-12. Dillon WP. Intrathecal gadolinium: its time has come? Comment on Gadolinium-enhanced MR cisternography to evaluate dural leaks in intracranial hypotension syndrome. AJNR Am J Neuroradiol. 2008 Jan;29(1):3-4. Kranz PG, Luetmer PH, Diehn FE, Amrhein TJ, Tanpitukpongse TP, Gray L.Myelographic Techniques for the Detection of Spinal CSF Leaks in Spontaneous Intracranial Hypotension. AJR Am J Roentgenol.2016 Jan;206(1):8-19. Jinkins JR, Rudwan M, Krumina G, Tali ETIntrathecal gadolinium-enhanced MR cisternography in the evaluation of clinically suspected cerebrospinal fluid rhinorrhea in humans: early experience. Radiology. 2002 Feb;222(2):555-9. Yoo HM, Kim SJ, Choi CG, Lee DH, Lee JH, Suh DC, Choi JW, Jeong KS, Chung SJ, Kim JS, Yun SC Detection of CSF leak in spinal CSF leak syndrome using MR myelography: correlation with radioisotope cisternography. AJNR Am J Neuroradiol.2008 Apr;29(4):649-54. Aydin K, Terzibasioglu E, Sencer S, Sencer A, Suoglu Y, Karasu A, Kiris T, Turantan MI. Localization of cerebrospinal fluid leaks by gadolinium-enhanced magnetic resonance cisternography: a 5-year single-center experience. Neurosurgery.2008 Mar;62(3):584-9;