# Feasibility of celiac axis delineation and treatment on combined magnetic resonance imaging and linear accelerator systems

## TL;DR

A new system combining MRI and radiation therapy improves targeting of celiac ganglia, reducing treatment risks and increasing effectiveness for pain management in pancreatic cancer.

## Contribution

The study demonstrates the feasibility of using MR-linac systems to delineate and treat celiac ganglia with higher precision.

## Key findings

- MR-linac systems enable better visualization of celiac ganglia compared to standard linacs.
- Treatment volumes using MR-linac were significantly smaller (median 0.8 cm³ vs. 32.2 cm³).
- Dose to organs-at-risk was reduced while dose to ganglia increased.

## Abstract

•Combined magnetic resonance imaging and linear accelerator systems can visualize celiac ganglia.•Due to the ability to see them, treatment volumes were greatly decreased.•Resulting dose to organs-at-risk was minimized, while dose to ganglia increased.

Combined magnetic resonance imaging and linear accelerator systems can visualize celiac ganglia.

Due to the ability to see them, treatment volumes were greatly decreased.

Resulting dose to organs-at-risk was minimized, while dose to ganglia increased.

Trials have been performed on irradiating celiac plexus for pancreatic cancer pain management. Images from a combined magnetic resonance imaging and linear accelerator system (MR-linac) for ten patients were assessed for delineation of celiac ganglia, aiming for smaller target volumes and reducing treatment risks versus standard linac-based treatments. MRI-linacs showed superior soft tissue contrast, enabling increased dose to ganglia while irradiating smaller target volumes versus regular linacs (median: 0.8 cm3 vs. 32.2 cm3, p < 0.05 for ten pairs of plans). While further studies are needed, MR-linac treatments could improve targeting precision, minimize dose to organs-at-risk and enhance effectiveness in palliative care.