Advanced Sandwich Composite Cores for Patient Support in Advanced Clinical Imaging and Oncology Treatment.

Robert H Morris,Nicola Doy,Nicasio R Geraldi,Michael I Newton,Jörg Pawelke,Aswin L Hoffmann,Abi Spicer,Johanna L Stafford,Lucy C Pike

doi:10.3390/ma13163549

Abstract

Ongoing advances in both imaging and treatment for oncology purposes have seen a significant rise in the use of not only the individual imaging modalities, but also their combination in single systems such as Positron Emission Tomography combined with Computed Tomography (PET–CT) and PET–MRI (Magnetic Resonance Imaging) when planning for advanced oncology treatment, the most demanding of which is proton therapy. This has identified issues in the availability of suitable materials upon which to support the patient undergoing imaging and treatment owing to the differing requirements for each of the techniques. Sandwich composites are often selected to solve this issue but there is little information regarding optimum materials for their cores. In this paper, we presented a range of materials which are suitable for such purposes and evaluated the performance for use in terms of PET signal attenuation, proton beam stopping, MRI signal shading and X-Ray CT visibility. We found that Extruded Polystyrene offers the best compromise for patient support and positioning structures across all modalities tested, allowing for significant savings in treatment planning time and delivering more efficient treatment with lower margins.

Highlights

In order to drive ever greater outcomes from oncology treatment, technological advances are being continuously made to deliver new therapies and better instruments
In the last few years, this has begun to be augmented with Positron Emission Tomography combined with Computed Tomography (CT) (PET–CT) which has the ability to differentiate between cancerous and benign regions of neoplasia as well as modifying plans during treatment in so called response adapted therapy [3], greatly reducing unnecessary treatment areas
The candidate cores suitable for use in advanced imaging and treatment modalities are tested for suitability in experiment on a proton therapy system and, Magnetic Resonance Imaging (MRI) and PET–CT imaging systems

Summary

Introduction

In order to drive ever greater outcomes from oncology treatment, technological advances are being continuously made to deliver new therapies and better instruments. One of the most recent advances is the use of proton therapy, where protons replace photons in traditional radiotherapy This has seen rapid growth from just 14 systems globally in 2004 to 104 operational, a further 38 in installation and commissioning and 28 more in the planning stage, thanks to highly improved patient outcomes [1]. Treatment is only half of the picture with the oncology workflow, with imaging being essential both to determine the best course of treatment and to plan the shape and location of the treatment beams in the case of intensity modulated therapies such as Intensity Modulated Radio-Therapy (IMRT) and Intensity Modulated Proton-Therapy (IMPT) [2] This imaging has traditionally been X-Ray Computed Tomography (CT) but over the past few decades has been slowly replaced by co-registered images from Magnetic Resonance Imaging (MRI) and CT owing to the superior soft tissue contrast which MRI brings. The plethora of techniques which are to be expected in a typical diagnosis, treatment planning and therapy cycle have uncovered a range of previously unforeseen challenges

Methods

Discussion

Conclusion