Deep inspiration breath-hold reduces esophageal dose in spinal stereotactic body radiotherapy: A feasibility study

We aimed to assess whether deep inspiration breath-hold (DIBH) could reduce esophageal dose by spinal stereotactic body radiotherapy (SBRT). In 25 patients with thoracic DIBH CT, the vertebral-esophageal distance significantly increased at T2-T9, greatest at Th7 (median 2.1 mm). Simulated SBRT plans showed a strong correlation between distance and esophageal dose, each 1 mm increase reducing 150 cGy. DIBH reduced the esophageal D_{0.03 cc} dose by a median of 411 cGy while maintaining positional reproducibility within 2 mm. These findings suggest that DIBH may reduce esophageal dose and warrants further study in patients with prior high-dose esophageal exposure.