Karlsson Bengt, Lax Ingmar, Yamamoto Masaaki, Söderman Michael, Jokura Hidefumi, Rosen Charles, Bailes Julian
Department of Neurosurgery, West Virginia University, Morgantown, West Virginia 26506, USA.
J Neurosurg. 2006 Dec;105 Suppl:183-9. doi: 10.3171/sup.2006.105.7.183.
The authors sought to assess the relationship between obliteration rate and different dose parameters following fractionated radiotherapy for arteriovenous malformations (AVMs). A comparison of the results of radiosurgery and radiotherapy for AVMs was made to calculate the best fit alpha/beta value, which would then be used as a model for predicting the treatment outcome, independent of the number of fractions applied.
Data from 1453 patients were analyzed: 1154 treated with radiosurgery and 300 with fractionated radiotherapy. The relationships between dose and obliteration rate after 3 years were calculated, and the best fit curve to the empirical results was defined. The higher the dose per fraction, biologically effective dose, and the lower the total dose, the higher the obliteration rate. The isoeffective doses when comparing radiotherapy and radiosurgery independent of the alpha/beta value could not be defined. The dose per fraction had the best predictive value, independent of the number of fractions.
Dose per fraction seems to be the decisive parameter for the treatment response following both radiotherapy and radiosurgery. A larger number of fractions did not increase the obliteration rate. The data indicate that higher doses per fraction should be used when irradiating AVMs.
作者试图评估动静脉畸形（AVM）分次放射治疗后闭塞率与不同剂量参数之间的关系。对AVM的放射外科治疗和放射治疗结果进行比较，以计算最佳拟合α/β值，该值随后将用作预测治疗结果的模型，而与应用的分次次数无关。
分析了1453例患者的数据：1154例接受放射外科治疗，300例接受分次放射治疗。计算了3年后剂量与闭塞率之间的关系，并确定了与实验结果最佳拟合的曲线。分次剂量、生物等效剂量越高，总剂量越低，闭塞率越高。在不考虑α/β值的情况下，无法确定放射治疗和放射外科治疗的等效剂量。分次剂量具有最佳的预测价值，与分次次数无关。
分次剂量似乎是放射治疗和放射外科治疗后治疗反应的决定性参数。分次次数增加并不会提高闭塞率。数据表明，照射AVM时应使用更高的分次剂量。
