⁶⁸Ga-DOTA PET for Diagnosis of Spinal Cerebrospinal Fluid Leaks

Abstract

Spontaneous intracranial hypotension (SIH) due to spinal cerebrospinal fluid (CSF) leakage causes substantial disease burden. In many patients, the course is protracted and refractory to conservative treatment, requiring targeted therapy. We propose positron emission tomography (PET) of the CSF space with 68 Ga-DOTA as a state-of-the-art approach of radionuclide cisternography (RC) and validate its diagnostic value.Methods: Retrospective analysis of patients with suspected intracranial hypotension due to spinal CSF leaks who underwent whole-body PET/CT at 1, 3 and 5 hours after intrathecal lumbar injection of 68 Ga-DOTA.Two independent raters blinded to clinical data analyzed all scans by for direct and indirect RC signs of CSF leakage. Volume of interest analysis was performed to assess the biological half-life of the tracer in CSF space (T 1/2,biol ) and the ratio of decay-corrected activity in CSF space at 5 and 3 hours (R5/3; simplified marker of tracer clearance). Comprehensive stepwise neuroradiological work-up served as reference, which was additionally validated by surgical findings and follow-up.Results: Of 40 consecutive patients, 39 patients with a working diagnosis of intracranial hypotension due to a spinal CSF leak (n=31 spontaneous and n=8 post-interventional) could be analyzed. A spinal CSF leak was verified by the neuroradiological reference method in 18 of 39 patients. As the only direct and indirect diagnostic signs, extrathecal tracer accumulation at the cervicothoracic junction and lack of activity over the cerebral convexities (5h) showed a high diagnostic value for spinal CSF leaks (sensitivity/specificity: 67%/90% and 94%/67%, respectively). Their combination provided little improvement (71%/95%).

Prof Cerebrospinal CNS-Leaks: State of the Art in Imaging Diagnosis with Special Focus on Intrathecal MRI Paramagnetic Contrast Agents Procedures

“…CSF PET with 68Ga-DOTA, is a novel fast approach of RC for verification, though not localization, of spinal CSF leaks which hold promise for its high sensitivity and specificity, and it has the potential of the imaging methods to reduce the burden to the patient who eventually undergo other localizing invasive methods 154 . Although further prospective studies are needed to be validated and it is also an expensive invasive method.…”

Radionuclide Cisternography with [64Cu]Cu-DOTA

“…The two most common PET radionuclides, fluorine-18 (half-life 110 min) and gallium-68 (half-life 68 min), are rather short-lived. So far, a study of [ 68 Ga-]Ga-DOTA has produced promising results for CSF leak detection with PET RNC [ 23 ]. Additionally, an 18 F-labeled fluorescein was successfully used for CSF imaging in rats [ 24 ].…”

64Cu-DOTA Enables Late PET Imaging and Leak Detection in the Cerebrospinal Fluid Space

“…Leak Detection in the Cerebrospinal Fluid Space TO THE EDITOR: Recently, PET of the cerebrospinal fluid (CSF) space with [ 68 Ga]Ga-DOTA has been proposed as a fast and convenient approach for verification of spinal CSF leaks (1). PETbased radiocisternography with [ 68 Ga]Ga-ethylenediaminetetraacetic acid, [ 55 Co]Co-diethylenetriaminepentaacetic acid (DTPA), and [ 64 Cu]Cu-DTPA was reported as early as 1982 (2,3).…”