Glynn Aisling M, Harwood Rachel, Garrett Bill, Harper Dean, Dunne Mary, Nicholson Jill, Rangaswamy Guhan, Duane Fran, Armstrong John, McArdle Orla, Brennan Sinead
St. Luke's Radiation Oncology Network, Dublin, Ireland.
Rep Pract Oncol Radiother. 2024 Jun 6;29(2):219-227. doi: 10.5603/rpor.99905. eCollection 2024.
Facemasks accurately immobilise patients with head and neck cancer (HNC) receiving radiotherapy (RT). However, such masks are associated with treatment related distress, a prognostic factor for poorer survival. Open masks offer increased comfort and patient satisfaction. We investigated whether open masks could immobilise patients without affecting treatment accuracy.
Over an 18-month period, all HNC RT patients with anxiety were offered open masks. Once 30 patients had completed treatment, set-up data was compared to patients in closed masks. The mean displacement and one-dimensional standard deviations (SD) of the mean, systematic and random set-up errors were calculated for translational directions: anterior-posterior (), superior-inferior (), medial-lateral (). The mean and SD of the mean was calculated for rotational displacements. Mann-Whitney U was used to determine any significant differences between set-up data.
Sixty patients were included (30 open & 30 closed masks). There was no statistically significant difference found in the x (p = 0.701), y (p = 0.246) or z (p = 0.535) direction for the SD of the mean displacements between both masks. No statistically significant difference was found in the SD of means for rotational displacements. The calculated planning target volume (PTV) margin requirements were minimally less for the closed masks 3.5, 2.6, and 2.7 mm (x, y, z, respectively) versus 4.2, 3.2, and 3.7 mm, respectively, for open masks.
Our study demonstrates that open masks maintain accuracy at levels comparable to closed masks in patients with anxiety. The minor difference in the calculated PTV margin could be rectified with daily on-line imaging or surface guided imaging.
面罩能准确固定接受放疗（RT）的头颈癌（HNC）患者。然而，此类面罩与治疗相关的痛苦有关，这是生存率较低的一个预后因素。开放式面罩能提高舒适度和患者满意度。我们研究了开放式面罩能否在不影响治疗准确性的情况下固定患者。
在18个月的时间里，为所有焦虑的HNC放疗患者提供开放式面罩。一旦30名患者完成治疗，将其摆位数据与使用封闭式面罩的患者进行比较。计算平移方向（前后（）、上下（）、内外（））上平均、系统和随机摆位误差的平均位移和一维标准差（SD）。计算旋转位移的平均值和标准差。使用曼-惠特尼U检验来确定摆位数据之间是否存在任何显著差异。
纳入60名患者（30名使用开放式面罩和30名使用封闭式面罩）。两种面罩之间平均位移标准差在x方向（p = 0.701）、y方向（p = 0.246）或z方向（p = 0.535）上均未发现统计学上的显著差异。旋转位移平均值的标准差也未发现统计学上的显著差异。计算得出的计划靶体积（PTV）边界要求，封闭式面罩略低于开放式面罩，分别为3.5、2.6和2.7毫米（分别对应x、y、z方向），而开放式面罩分别为4.2、3.2和3.7毫米。
我们的研究表明，对于焦虑患者，开放式面罩能保持与封闭式面罩相当的准确性水平。计算得出的PTV边界的微小差异可通过每日在线成像或表面引导成像来纠正。
