Quantitative dual-energy computed tomography with cesium as a novel contrast agent for localization of thermochemical ablation in phantoms and ex vivo models.

Autor: Thompson EA; Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA., Jacobsen MC; Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA., Fuentes DT; Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA., Layman RR; Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA., Cressman ENK; Department of Interventional Radiology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
Jazyk: angličtina
Zdroj: Medical physics [Med Phys] 2023 Dec; Vol. 50 (12), pp. 7879-7890. Date of Electronic Publication: 2023 Jul 06.
DOI: 10.1002/mp.16558
Abstrakt: Background: Thermochemical ablation (TCA) is a minimally invasive therapy under development for hepatocellular carcinoma. TCA simultaneously delivers an acid (acetic acid, AcOH) and base (sodium hydroxide, NaOH) directly into the tumor, where the acid/base chemical reaction produces an exotherm that induces local ablation. However, AcOH and NaOH are not radiopaque, making monitoring TCA delivery difficult.
Purpose: We address the issue of image guidance for TCA by utilizing cesium hydroxide (CsOH) as a novel theranostic component of TCA that is detectable and quantifiable with dual-energy CT (DECT).
Materials and Methods: To quantify the minimum concentration of CsOH that can be positively identified by DECT, the limit of detection (LOD) was established in an elliptical phantom (Multi-Energy CT Quality Assurance Phantom, Kyoto Kagaku, Kyoto, Japan) with two DECT technologies: a dual-source system (SOMATOM Force, Siemens Healthineers, Forchheim, Germany) and a split-filter, single-source system (SOMATOM Edge, Siemens Healthineers). The dual-energy ratio (DER) and LOD of CsOH were determined for each system. Cesium concentration quantification accuracy was evaluated in a gelatin phantom before quantitative mapping was performed in ex vivo models.
Results: On the dual-source system, the DER and LOD were 2.94 and 1.36-mM CsOH, respectively. For the split-filter system, the DER and LOD were 1.41- and 6.11-mM CsOH, respectively. The signal on cesium maps in phantoms tracked linearly with concentration (R 2  = 0.99) on both systems with an RMSE of 2.56 and 6.72 on the dual-source and split-filter system, respectively. In ex vivo models, CsOH was detected following delivery of TCA at all concentrations.
Conclusions: DECT can be used to detect and quantify the concentration of cesium in phantom and ex vivo tissue models. When incorporated in TCA, CsOH performs as a theranostic agent for quantitative DECT image-guidance.
(© 2023 American Association of Physicists in Medicine.)
Databáze: MEDLINE