Clinical introduction of a commercial treatment chair to facilitate thorax irradiation

Abstract

There are occasions when patients can benefit significantly from being treated upright. This technique is beneficial in the treatment of Hodgkin's disease when the mediastinum is involved. The main henefit is the lung volume spared resulting from narrowing of a bulky mediastinum. We purchased a commercial treatment chair to facilitate upright treatment. Clinical implementation required rigorous testing, documentation of procedures, and acknowledgment of and corresponding solutions to limitations. The purchased chair is designed to couple with the spine bar of the treatment couch, allowing patient positioning via pendant functions. The chair has no obstruction as immobilization is afforded by arm, shoulder, and knee supports, which allows isocentric treatments. An additional hydraulic mount is used for simulation. We have treated five patients thus far, including Hodgkin's disease patients with and without mediastinal involvement, and one lung cancer patient with a large lower lobe lesion. All patients have benefited by having a greater volume of lung spared (as much as 60% additional blocking) when upright simulation films are compared with supine and prone films. Immobilization has been adequate as confirmed by daily light field projections and portal films. We are routinely evaluating Hodgkin's disease patients for upright treatment. Patients treated in the chair have benefited in terms of lung volume spared without loss of immobilization. A patient with a large lower lobe lung lesion has also benefited as the tumor “dropped,” thus affording lung sparing via blocking.