Senova Suhan, Aggad Mourad, Golmard Jean-Louis, Hasboun Dominique, Lamproglou Ioannis, Jenny Catherine, Cornu Philippe, Mazeron Jean-Jacques, Valéry Charles A
Unité de Radiochirurgie Gamma Knife, Region Ile De France, Paris, France; Service de Neurochirurgie, Centre Hospitalier Universitaire (CHU) La Pitié-Salpêtrière, Assistance Publique des Hôpitaux de Paris, Université Pierre et Marie Curie, Paris, France; Inserm, U955, Equipe 14, Université Paris Est, Faculté de médecine, Créteil, France.
Unité de Radiochirurgie Gamma Knife, Region Ile De France, Paris, France; Service de Neurochirurgie, Centre Hospitalier Universitaire (CHU) La Pitié-Salpêtrière, Assistance Publique des Hôpitaux de Paris, Université Pierre et Marie Curie, Paris, France.
Int J Radiat Oncol Biol Phys. 2016 Jun 1;95(2):721-8. doi: 10.1016/j.ijrobp.2016.01.012. Epub 2016 Jan 15.
To analyze the relationship between dosimetric characteristics and symptoms related to trigeminal neuropathy (TN) observed after radiosurgery (RS) for vestibular schwannomas (VS); to propose guidelines to optimize planification in VS RS regarding TN preservation; and to detail the mechanism of TN impairment after VS RS.
One hundred seventy-nine patients treated between 2011 and 2013 for VS RS and without trigeminal impairment before RS were included in a retrospective study. Univariate and multivariate analyses were performed to determine predictors of TN among characteristics of the patients, the dosimetry, and the VS.
There were 20 Koos grade 1, 99 grade 2, 57 grade 3, and 3 grade 4. Fourteen patients (7.8%) presented a transitory or permanent TN. Between the patients with and without TN after VS RS, there was no significant difference regarding dosimetry or VS volume itself. Significant differences (univariate analysis P<.05, Mann-Whitney test) were found for parameters related to the cisternal portion of the trigeminal nerve: total integrated dose, maximum dose, mean dose, volume of the Vth nerve (Volv), and volume of the Vth nerve receiving at least 11 Gy (VolVcist>11Gy), but also for maximal dose to the Vth nerve nucleus and intra-axial portion (Dose maxVax). After multivariate analysis, the best model predicting TN included VolVcist>11Gy (P=.0045), Dose maxVax (P=.0006), and Volv (P=.0058). The negative predictive value of this model was 97%.
The parameters VolVcist>11Gy, Dose maxVax, and Volv should be checked when designing dosimetry for VS RS.
分析前庭神经鞘瘤（VS）放射外科治疗（RS）后观察到的剂量学特征与三叉神经病变（TN）相关症状之间的关系；提出关于在VS RS中优化计划以保护TN的指南；并详细阐述VS RS后TN损伤的机制。
对2011年至2013年间接受VS RS治疗且在RS前无三叉神经损伤的179例患者进行回顾性研究。进行单因素和多因素分析以确定患者特征、剂量学和VS特征中TN的预测因素。
有20例库斯1级、99例2级、57例3级和3例4级。14例患者（7.8%）出现短暂或永久性TN。在VS RS后有和没有TN的患者之间，在剂量学或VS体积本身方面没有显著差异。在与三叉神经脑池段相关的参数方面发现了显著差异（单因素分析P<0.05，曼-惠特尼检验）：总积分剂量、最大剂量、平均剂量、第五神经体积（Volv）以及接受至少11 Gy的第五神经体积（VolVcist>11Gy），但对于第五神经核和轴内部分的最大剂量（Dose maxVax）也有差异。多因素分析后，预测TN的最佳模型包括VolVcist>11Gy（P = 0.0045）、Dose maxVax（P = 0.0006）和Volv（P = 0.0058）。该模型的阴性预测值为97%。
在设计VS RS的剂量学时应检查参数VolVcist>11Gy、Dose maxVax和Volv。
