Dosimetric Study of Total Marrow and Lymphoid Irradiation on a Ring Gantry-Based Medical Linac with a Two-Layer Multi-Leaf Collimator
Abstract
PURPOSE/OBJECTIVE(S)
In this study, we aimed to evaluate dosimetric quality of total marrow and lymphoid irradiation (TMLI) plans for a ring gantry-based medical Linac with a two-layer multi-leaf collimator.
MATERIALS/METHODS
We retrospectively retrieved treatment planning CT images, structure sets, and plan dose for four adult patients, two male and two female, who previously received TMLI treatments on helical tomotherapy (HT) at our institution. TMLI plans were optimized for a ring gantry-based medical Linac with a two-layer multi-leaf collimator (Halcyon, Varian Medical Systems, Inc., Palo Alto, CA). A prescription dose of 12 Gy in 8 fractions was prescribed to the skeletal bones from the skull to mid-thigh, spleen, spinal canal, and lymphoid volume. Five or six isocenters were placed with equal spacing along the patient's longitudinal direction in each TMLI plan with two 6-MV flattening filter-free volumetric modulated arc therapy (VMAT) fields at each isocenter. Isocenter separation ranged from 15 cm to 16.5 cm. Each VMAT field has a field size of 28 cm to 28 cm with the collimator at 90° and a full gantry rotation. The nominal dose rate was 800 MU/minute, and the maximum gantry rotation speed was 24°/sec. Institutional dosimetric constraints were used for optimization including a mean lung dose limit of less than 8 Gy. All the plans were normalized so that 85% the primary planning target volume received the prescription dose.
RESULTS
The average mean doses to the…
Read the paper
Related studies
- Lathyrism-induced alterations in collagen cross-links influence the mechanical properties of bone material without affecting the mineral
- High-Resolution SPECT-CT/MR Molecular Imaging of Angiogenesis in the Vx2 Model
- Severely impaired bone material quality in Chihuahua zebrafish resembles classical dominant human osteogenesis imperfecta
- Small-animal SPECT and SPECT/CT: application in cardiovascular research
- Intravital imaging of osteocytes in mouse calvaria using third harmonic generation microscopy
- Techniques and Evaluation From a Cross-Platform Imaging Comparison of Quantitative Ultrasound Parameters in an In Vivo Rodent Fibroadenoma Model
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.