Quantification of Cerenkov Luminescence Imaging (CLI) Comparable With 3-D PET Standard Measurements.

In this study, we developed a model that estimates effective tissue attenuation coefficient and corrects the tissue attenuation of CLI signal intensity independent of tissue depth and size. To evaluate this model, we used several thin slices of ham as a phantom and placed a radionuclide (89Zr and 64Cu) inside the phantom at different tissue depths and sizes (2, 7, and 12 mm). We performed 2-D CLI and MicroPET/CT (Combined small animal PET and Computed Tomography (CT)) imaging of the phantom and in vivo mouse model after administration of 89Zr tracer. Estimates of the effective tissue attenuation coefficient (μeff) for 89Zr and 64Cu were ∼2.4 and ∼2.6 cm-1, respectively. The computed unit conversion factor to %ID/g from 2-D CLI signal was 2.74 × 10-3 μCi/radiance estimated from phantom study. After applying tissue attenuation correction and unit conversion to the in vivo animal study, an average quantification difference of 10% for spleen and 35% for liver was obtained compared to PET measurements. The proposed model provides comparable quantification accuracy to standard PET system independent of deep tissue CLI signal attenuation. PMID: 30043654 [PubMed - in process]
Source: Molecular Imaging - Category: Radiology Tags: Mol Imaging Source Type: research