High-Resolution PET Cisternography With 64Cu-DOTA for CSF Leak Detection Intracranial hypotension may lead to chronic, debilitating symptoms, and severe complications. The underlying CSF leak may be difficult to localize. To establish a new diagnostic option for the detection of CSF leaks, 64Cu-DOTA was developed as a tracer for PET imaging. PET/CT imaging was possible with high resolution and without complications. In one patient, the exact site of a dural tear was identified, enabling successful surgical treatment. PET cisternography with 64Cu-DOTA appears to be safe and able to locate a CSF leak. It has the potential to be a problem-solving modality in cases with inconclusive CT, MR, and/or scintigraphic findings.