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Objectives: This study aims to explore the synergistic effects of combining Stereotactic Body Radiation Therapy (SBRT) and Selective Internal Radiation Therapy (SIRT) in that specific sequence for treating hepatocellular carcinoma (HCC), particularly in patients at high risk of radiation-induced liver disease (RILD)., Methods: We analyzed a case of a patient with HCC who was treated with SBRT at our institution. A virtual 90Y dose distribution was added using our in-house -BLINDED FOR REVIEW- model to keep a minimum dose to the healthy liver tissue. BED and EUD metrics were calculated to harmonize the dose distributions of SBRT and SIRT., Results: Our radiation biology-based models suggest that the combination of SBRT and SIRT could maintain effective tumor control while reducing the dose to normal liver tissue. Specifically, an SBRT plan of 10 Gy x 3 fractions combined with SIRT yielded comparable tumor control probability to an SBRT-only plan of 10 Gy x 5 fractions., Conclusion: The combination of SBRT and SIRT is a promising treatment strategy for HCC patients at high risk of RILD. While the LQ model and associated formalisms provide a useful starting point, further studies are needed to account for factors beyond these models. Nonetheless, the potential for significant dose reduction to normal tissue suggests that this combination therapy could offer substantial clinical benefits., Advances in Knowledge: This article presents a proposal to combine SBRT and SIRT, in this specific order, for HCC, discussing its advantages. A framework for future research into optimizing combination therapy for HCC is provided, utilizing a novel HCC vascular model to simulate 90Y doses., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Institute of Radiology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objective. To investigate different dosimetric aspects of 90 Y-IsoPet™ intratumoral therapy in canine soft tissue sarcomas, model the spatial spread of the gel post-injection, evaluate absorbed dose to clinical target volumes, and assess dose distributions and treatment efficacy. Approach. Six canine cases treated with 90 Y-IsoPet™ for soft tissue sarcoma at the Veterinary Health Center, University of Missouri are analyzed in this retrospective study. The dogs received intratumoral IsoPet™ injections, following a grid pattern to achieve a near-uniform dose distribution in the clinical target volume. Two dosimetry methods were performed retrospectively using the Monte Carlo toolkit OpenTOPAS: imaging-based dosimetry obtained from post-injection PET/CT scans, and stylized phantom-based dosimetry modeled from the planned injection points to the gross tumor volume. For the latter, a Gaussian parameter with variable sigma was introduced to reflect the spatial spread of IsoPet™. The two methods were compared using dose-volume histograms (DVHs) and dose homogeneity, allowing an approximation of the closest sigma for the spatial spread of the gel post-injection. In addition, we compared Monte Carlo-based dosimetry with voxel S-value (VSV)-based dosimetry to investigate the dosimetric differences. Main results. Imaging-based dosimetry showed differences between Monte Carlo and VSV calculations in tumor high-density areas with higher self-absorption. Stylized phantom-based dosimetry indicated a more homogeneous target dose with increasing sigma. The sigma approximation of the 90 Y-IsoPet™ post-injection gel spread resulted in a median sigma of approximately 0.44 mm across all cases to reproduce the dose heterogeneity observed in Monte Carlo calculations. Significance. The results indicate that dose modeling based on planned injection points can serve as a first-order approximation for the delivered dose in 90 Y-IsoPet™ therapy for canine soft tissue sarcomas. The dosimetry evaluation highlights the non-uniformity of absorbed doses despite the gel spread, emphasizing the importance of considering tumor dose heterogeneity in treatment evaluation. Our findings suggest that using Monte Carlo for dose calculation seems more suitable for this type of tumor where high-density areas might play an important role in dosimetry., (© 2024 Institute of Physics and Engineering in Medicine.)

Background: The prevalence of hypertension comorbid with diabetes is a significant health care issue. Use of the home blood pressure monitor (HBPM) for aiding in the control of hypertension is noteworthy because of benefits that accrue from following a home measurement regimen. To be usable by blind and visually impaired patients, HBPMs must have speech output to convey all screen information, an easily readable visual display, identifiable controls that are easy to use, and an accessible user manual., Methods: Data on the physical aspects and the features and functions of nine Food and Drug Administration-approved HBPMs (eight of which were recommended by the British Hypertension Society) were tabulated and analyzed for usability by blind and visually impaired individuals. Video Electronics Standards Association standards were used to measure contrast modulation in the displays of the HBPMs. Ten persons who are blind or visually impaired and who have diabetes were surveyed to determine how they monitor their blood pressure and to learn their ideas for improvements in usability., Results: Physical controls were found to be easy to identify, and operating procedures were found to be relatively simple on all of the HBPMs, but user manuals were either inaccessible or minimally accessible to blind persons. The two HBPMs that have speech output do not voice all of the information that is displayed on the screen. Some functions that are standard in the HBPMs without speech output, such as the feature for automatically setting cuff inflation volume and memory, were lacking in the HBPMs with speech output. These features were mentioned as desirable in interviews with legally blind persons who are diabetic and who monitor their blood pressure at home. Visual display output was large and adequate in all of the HBPMs. Michelson contrast for numeric digits in the HBPM displays was also measured, ranging from 55 to 75% for characters with dominant spatial frequency components lying in the range of 0.5-1.0 cycles/degree., Conclusions: Home blood pressure monitors are easy-to-use devices that do not present accessibility barriers that are difficult to surmount, either technically or operationally. Two HBPMs with voice output were found to have a significant degree of accessibility, but they were not found to offer as many features as those HBPMs that were less accessible. Recommendations were made to improve accessibility, including the development of visual display standards that specify a minimally acceptable level of Michelson contrast.