A Single-Dose Intravenous-Contrast Enhanced 4-Dimensional Computed Tomogram Facilitated Accurate Delineation and Tracking Metastatic Tumor Motion Within a Cardiac Chamber in all Breathing Phases for Cardiac Metastasis-Directed Radiation Therapy

Figures

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  Figure 1. (A) Axial view of computed tomogram (CT) without intravenous contrast (IV-contrast) before radiation therapy (RT). (B) Echocardiogram showing a 4.5 × 4.3 cm in size cardiac metastasis (CM, white arrowhead) in the right ventricle (RV) before RT. (C) Positron emission tomography (PET) scan showing hypermetabolic CM in RT with maximum standardized uptake value (SUVmax) of 10 (white arrowhead) before CM-directed RT. (D) Axial view of an CM-directed RT plan on average image of a single doses IV-contrast enhanced 4-dimensional CT. (E) Echocardiogram at 3 days after CM-directed RT showing a 1.8 × 3 cm in size CM (white arrowhead) in RV. (F) PET scan at 3 weeks after CM-directed RT showing decreased SUVmax of 4.1 in RV compared to prior PET (Fig. 1C). Abbreviation: 4DCT = 4-dimensional computed tomography.

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  Figure 2. (A) Axial views of a single-dose intravenous contrast (IV-contrast) enhanced 4-dimensional computed tomogram in breathing phase of 0% to 90%. White arrowhead points the cardiac metastasis in the right ventricle. (B) Dose-volume (percentage volume, %) histogram of CM-directed stereotactic body radiation therapy. (C2) Dose-volume histogram of CM-directed radiation therapy. Abbreviation: Organ XX_eval = organ XX minus planning target volume.