An [¹⁸F]-Positron-Emitting, Fluorescent, Cerebrospinal Fluid Probe for Imaging Damage to the Brain and Spine

Abstract

Fluorescein is modified to bear ¹⁸F so that it can act as both a positron emitter, and a fluorophore, allowing detection by positron emission tomography (PET), scintillation, and fluorescent imaging (FL). [¹⁸F]-<b>2</b> is injected into the intrathecal space of rats and used to observe the cerebrospinal fluid (CSF) that bathes the brain and spine. Injury in three different applications is visualized with [¹⁸F]-<b>2</b>: 1) detection of a 0.7 mm paranasal-sinus CSF leak (CSFL); 2) detection of 0.5 mm puncture damage to the thoracic spine (acute spinal cord injury); and 3) detection of intracerebral hemorrhage/edema because of traumatic brain injury. In all models, the location of injury is visualized with [¹⁸F]-<b>2</b> at high resolution. [¹⁸F]-<b>2</b> PET imaging may be a superior alternative to current clinical contrast myelography and ¹³¹I, ¹¹¹In or ^99mTc radionuclide cisternography. Like fluorescein, [¹⁸F]-<b>2</b> may also have other uses in diagnostic or fluorescence guided medicine.