Massager Nicolas, Murata Noriko, Tamura Manabu, Devriendt Daniel, Levivier Marc, Régis Jean
Gamma Knife Center, Université Libre de Bruxelles, Brussels, Belgium.
Neurosurgery. 2007 Apr;60(4):681-7; discussion 687-8. doi: 10.1227/01.NEU.0000255393.77538.75.
The authors conducted a comparative study to analyze dosimetry and results to understand the significant difference in the rate of trigeminal dysfunction after gamma knife radiosurgery for trigeminal neuralgia between two centers using the same target.
The data of 358 patients (109 patients from Brussels and 259 patients from Marseilles) were analyzed. Three different dosimetric strategies were found: treatment with less than 90 Gy and no selective beam channel blocking (Group 1; patients from Marseilles only), treatment with 90 Gy and no selective beam channel blocking (Group 2; patients from Brussels and Marseilles), or treatment with 90 Gy and use of selective beam channel blocking (Group 3; patients from Brussels only).
The prescription dose and the use of selective beam channel blocking have been significantly associated with a higher energy received by the retrogasserian trigeminal nerve root. The different radiation dose delivered to the nerve root in these three groups of patients was significantly associated with the incidence of mild (15, 21, and 49% for Groups 1, 2, and 3, respectively) and bothersome (1.4, 2.4, and 10% for Groups 1, 2, and 3, respectively) trigeminal dysfunction. The good and excellent rates of pain relief were 81 and 66%, respectively, for Group 1, 85 and 77%, respectively, for Group 2, and 90 and 84%, respectively, for Group 3, and were also related to the amount of energy received by nerve root volume.
Using a similar target, the incidence of trigeminal dysfunction and the pain relief rate can vary according to the radiation energy received by the retrogasserian part of the trigeminal nerve root. The prescription dose and the use of beam channel blocking modify the integrated dose delivered to the nerve and may contribute to the different rates of trigeminal numbness and pain outcome. The radiobiological effect of gamma knife radiosurgery may be related to the energy delivered to nerve root volume, rather than to the maximal dose delivered.
作者进行了一项对比研究，分析剂量测定和结果，以了解在使用相同靶点对三叉神经痛进行伽玛刀放射外科治疗后，两个中心三叉神经功能障碍发生率的显著差异。
分析了358例患者的数据（109例来自布鲁塞尔，259例来自马赛）。发现了三种不同的剂量测定策略：小于90 Gy且无选择性束流通道阻断的治疗（第1组；仅马赛的患者），90 Gy且无选择性束流通道阻断的治疗（第2组；布鲁塞尔和马赛的患者），或90 Gy且使用选择性束流通道阻断的治疗（第3组；仅布鲁塞尔的患者）。
处方剂量和选择性束流通道阻断的使用与半月节后三叉神经根接受的较高能量显著相关。这三组患者给予神经根的不同辐射剂量与轻度（第1、2、3组分别为15%、21%和49%）和烦人的（第1、2、3组分别为1.4%、2.4%和10%）三叉神经功能障碍的发生率显著相关。第1组疼痛缓解的良好率和优秀率分别为81%和66%，第2组分别为85%和77%，第3组分别为90%和84%，也与神经根体积接受的能量量有关。
使用相似的靶点，三叉神经功能障碍的发生率和疼痛缓解率可能因三叉神经根半月节后部分接受的辐射能量而异。处方剂量和束流通道阻断的使用改变了传递到神经的积分剂量，并可能导致三叉神经麻木和疼痛结果的不同发生率。伽玛刀放射外科的放射生物学效应可能与传递到神经根体积的能量有关，而不是与最大剂量有关。
