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Accurate imaging of radiopharmaceuticals across a broad photon energy spectrum is critical in nuclear medicine for diagnosis, dosimetry, and for monitoring cancer treatment. This is specially true for targeted radionuclide therapy, where direct imaging and quantification are vital to leverage the therapeutic potential of this approach. Over the past decades, Single Photon Emission Computed Tomography (SPECT) has become the leading imaging modality for gammaray emitting radionuclides. However, its limited sensitivity and narrow energy range pose a significant challenge for imaging emerging therapeutic radiopharmaceuticals. A high-sensitivity imaging solution capable of handling both low- and high-energy gamma rays is still an unmet need in the clinic. In this work, we propose as a solution a collimated Compton camera consisting of a 3D-positioning gamma-ray tracking detector system combined with a parallel-hole collimator capable of performing Compton imaging for high-energy gamma rays and SPECT imaging for lowenergy gamma rays. Using this concept, we performed simultaneous imaging in the 30-300 KeV range using SPECT, in the 300-400 keV range using a combination of SPECT and Compton, and above 400 keV exclusively using Compton imaging. We measured the Compton and SPECT sensitivities of 64(8) cps MBq at 440 keV and 62(8) cps MBq at 218 keV, respectively, for only a single detector head. A practical application in nuclear medicine is for imaging of <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">225</sup> Ac, a promising alpha emitter for tumor treatment that also emits gamma rays across a wide energy range. We demonstrate broad-energy imaging of <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">225</sup> Ac and its daughters in point sources and a mouse phantom. Our concept could offer a versatile imaging solution for most of the relevant therapy and diagnose radionuclides.