| The full potential of nuclear medicine, especially for therapeutic applications, has not yet been reached. Accurate dosimetry in patients undergoing radionuclide therapy, or in animal subjects used during pre-clinical trials, is paramount to aid in the progress of the field. Whether dosimetry is used for treatment planning or to establish the dose limits and efficacy of a new drug, its implementation needs to be time-efficient and reliable to ensure success. This work presents two new tools that aim to help mitigate the current issues: a detailed canine skeletal model for skeletal dosimetry in pre-clinical trials, and a dosimetry software for dose calculations in normal and tumor-burdened anatomy. A detailed canine skeletal model was constructed to complement the existing UFDog anatomical phantom. This skeletal model provides a comprehensive mass table of the different skeletal tissues in each bone site, as well as absorbed and specific absorbed fractions for the active marrow and endosteum targets. Several different bone and marrow sources are considered. This model is the first of its kind and it gives researchers and veterinary doctors the option of using canine-specific values in their calculations instead of having to apply human ones. The dosimetry software constructed during this work performs normal and tumorburdened anatomy dosimetry in a fast yet reliable manner. There are several human phantoms, and a canine one embedded in the code. Normal anatomy calculations are performed following the MIRD schema and using absorbed fractions previously calculated with radiation transport code MCNPX. Tumor-burdened anatomy calculations require the user to define the center and axis lengths of the ellipsoid that represents the tumor. Once the information is collected, the code inserts the tumor into the phantom of choice and dosimetry is performed using dose point kernels. This software can handle heterogeneities in the medium and it provides results in just a few minutes with errors well below 10% in most cases, for tumor-burdened dosimetry. |
