Purpose: To provide the adult ICRP mesh-type reference computational phantom (MRCP) with a more anatomically realistic renal macro-anatomy through the creation of the renal pyramids and renal pelvis and the development of intra-organ blood vessels model with a blood vasculature. Dosimetry applications include 1) computation of blood DVHs during external beam radiotherapy treatment of kidney tumors, and 2) differentiation of radionuclide decay sites within the kidney tissues from those occurring in the blood content of the kidneys.
Methods: The MRCP model was altered with the use of 3D modeling software Rhinoceros 3D. Improvements to the model included the addition of eight medullary pyramids, removal of the existing ICRP misplaced renal pelvis and the creation of a new correctly placed renal pelvis, construction of the main kidney vasculature (from renal arteries and veins up to interlobar arteries and veins), and creation of arterial and venous vascular trees using the Constrained Constructive Optimization method.
Results: The following results are for the adult male left kidney: The kidney capsule from the MRCP model remained unchanged with its volume of 197.86 ml and is inclusive of the renal cortex, medulla, and organ blood. Our revised model has 8 medullary pyramids composing a total of ~41ml. The model consists of 32 vascular trees with near 4400 vessels modeled as cylindrical pipes capturing near 15% of the total kidney blood volume. The vessels’ radii range from several millimeters to 0.065-0.25 mm at the terminal vessels.
Conclusion: The adult MRCP male left kidney model was corrected for its macro-anatomy with the creation of renal pyramids and a renal pelvis. Vasculature was created by the implementation of the vessel-generation algorithm. This model will help to create more optimized protection against deterministic radiobiological effects in the human kidney, which has been the dose-limiting organ in recent RPT clinical trials
Funding Support, Disclosures, and Conflict of Interest: This research is supported by NIH R01 CA248901 and NIH R21 CA248118
Radiation Dosimetry, Blood Vessels, Phantoms
IM/TH- Radiopharmaceutical Therapy: Dose estimation: Monte Carlo