Upright Radiation Therapy—A Historical Reflection and Opportunities for Future Applications

Abstract

Since the early days of megavoltage Radiation Therapy (RT), the potential of delivering treatment to a sub group of patients in an upright position has been recognized. Compared to lying horizontally, treating patients in an upright position offers potential benefits in terms of patient comfort especially for patients experiencing dyspnoea and saliva accumulation when lying down. Dosimetric benefits can also be gained from changes in the volume and location of lungs and heart in an upright position, which are potentially advantageous for clinical situations including Hodgkin's disease, lung and breast malignancies. Since the 1950's, upright stabilization mechanisms have ranged from standalone chair based apparatus to couch-top attachments with increasingly customizable solutions. The introduction of Computed-Tomography (CT) based three-dimensional (3D) dosimetry in the 1980's−90's necessitated image acquisition in a horizontal position (supine or prone), significantly reducing options for alternative patient positioning and upright techniques. Despite this, upright techniques have still been utilized where clinically indicated for palliative and novel approaches often involving non-standard treatment scenarios. More recently, a small number of centers have reported on specialized equipment capable of acquiring planning data with the patient in a vertical position. The possibility of acquiring planning quality Cone Beam CT (CBCT) on linear accelerators has recently reinvigorated the potential to deliver highly accurate and targeted treatments to patients in an upright position. This paper reflects on the historical applications of upright RT and explores new possibilities for this technology in modern RT departments.

Validation and practical implementation of seated position radiotherapy in a commercial TPS for proton therapy

“…Chair-based treatments in the seated position are very common in particle therapy centers when a full gantry is not available. Chair-based treatments may also be needed for some patients who cannot tolerate lying flat either due to cancer or other underlying condition [14][15][16][17]. We verified that RayStation's implementation of the pitch, roll, and yaw is consistent with IEC standard 61217 and matches our physical couch positioning system.…”

Future Developments in Charged Particle Therapy: Improving Beam Delivery for Efficiency and Efficacy

“…shielding) and the use of upright chairs is now being reconsidered. Seated positioning is typical for ocular treatments and for some specific disease sites; it was also historically the method used at pioneering facilities yet with less success than supine treatments ( 108 ). Now, with the advent of modern delivery techniques, superior dose distributions can be achieved with seated treatments and clinical advantages with better immobilisation have also been reported ( 109 ).…”

Measurements of human tolerance to horizontal rotation within an MRI scanner: Towards gantry‐free radiation therapy

“…When considering gantry-free radiation therapy, there are two ways to rotate the patient, in the horizontal direction, as performed here, or in the upright direction, as has been studied elsewhere. 7,25,26 The advantages of horizontal rotation are that existing imaging devices used for treatment planning and image-guided delivery can be more easily integrated with a horizontal approach, while vertical rotation would require dedicated upright imaging systems and new approaches to treatment planning. 27 Conversely, upright rotation does not introduce anatomical deformations during rotation which compromise treatments 9 and the upright position is generally more tolerable for patients.…”