Evaluation of a Sinmed shoulder support cushion for head and neck immobilisation

Purpose : Accuracy and reproducibility of patient positioning is a central issue in the successful delivery of radiation therapy treatment. As treatment techniques become increasingly conformal, this issue has become ever more important. With the recent implementation of Intensity Modulated Radiation Therapy (IMRT) for head and neck patients, the Princess Alexandra Hospital Radiation Oncology Department has been investigating optimal immobilisation techniques for these patients. Methods : As part of this investigation, the department has recently trialled the inclusion of a modified Sinmed shoulder support cushion (CIVCO Medical Solutions, Kalona IA, USA) as part of the standard positioning protocol for head and neck patients. After trialling this piece of equipment on a small group of patients, an evaluation was undertaken to assess its effect on patient positioning accuracy. This evaluation consisted of electronic portal imaging assessment and collation of observations from treatment and planning staff. Results : No major differences were found between the positioning accuracy achieved for patients positioned with the support cushion in comparison to those positioned as per departmental protocol. Furthermore, trends were noted that indicated the support cushion actually decreased the level of positioning accuracy that was achieved. Staff observation demonstrated that the support cushion was not easy to use and contributed to problematic shell fitting in daily practice. Conclusion : As a result, the shoulder support cushion has not been implemented as part of the department's protocol for head and neck patient positioning with its use being limited to those patients who would most benefit from its inclusion due to anatomical restrictions.