Clark B G, Podgorsak E B, Souhami L, Olivier A, Sixel K E, Caron J L
Department of Medical Physics, Montréal General Hospital, McGill University, Québec, Canada.
Br J Radiol. 1993 Jun;66(786):522-7. doi: 10.1259/0007-1285-66-786-522.
Stereotactic radiosurgery has become established as an effective treatment modality for certain non-malignant brain diseases such as arteriovenous malformations. This paper describes an extension of our linear accelerator-based radiosurgical technique to fractionated treatment of intracranial disease. The fractionated stereotactic radiotherapy technique expands the use of the modality by sparing normal cells within the treatment volume thus improving the therapeutic ratio. The first treatment is given using a stereotactic frame both for target localization and patient immobilization. The frame is then removed and subsequent treatments use a standard neurosurgical halo-ring for patient immobilization. The halo-ring is left in place on the skull for the duration of the course of treatment. Thus the physical requirements for fractionation pertain firstly to the patient immobilization and target localization using the halo-ring and secondly to the stringent quality assurance procedures required to maintain spatial accuracy under these new conditions. We describe a sensitive and effective technique for checking the rotational beam parameters and collimator alignment which we use immediately prior to treatment to ensure adequate accuracy of dose delivery to the target volume.
立体定向放射外科已成为治疗某些非恶性脑部疾病（如动静脉畸形）的有效治疗方式。本文描述了我们基于直线加速器的放射外科技术在颅内疾病分次治疗中的扩展应用。分次立体定向放射治疗技术通过在治疗体积内保护正常细胞来扩大该治疗方式的应用范围，从而提高治疗比。首次治疗使用立体定向框架进行靶点定位和患者固定。然后移除框架，后续治疗使用标准神经外科头环进行患者固定。头环在整个治疗过程中留在颅骨上。因此，分次治疗的物理要求首先涉及使用头环进行患者固定和靶点定位，其次涉及在这些新条件下维持空间精度所需的严格质量保证程序。我们描述了一种用于检查旋转束参数和准直器对准的灵敏且有效的技术，我们在治疗前立即使用该技术以确保向靶体积输送剂量的足够准确性。
