Huang Chih-Ying, Peng Syu-Jyun, Yang Huai-Che, Wu Hsiu-Mei, Chen Ching-Jen, Wang Mao-Che, Hu Yong-Sin, Lin Chung-Jung, Shiau Cheng-Ying, Guo Wan-Yuo, Chung Wen-Yuh, Pan David Hung-Chi, Lee Cheng-Chia
Department of Radiology, Taipei Veterans General Hospital, Taipei , Taiwan.
School of Medicine, National Yang Ming Chiao Tung University, Taipei , Taiwan.
Neurosurgery. 2023 Dec 1;93(6):1383-1392. doi: 10.1227/neu.0000000000002599. Epub 2023 Jul 11.
The pathophysiology of vestibular schwannoma (VS) pseudoprogression after Gamma Knife radiosurgery (GKRS) remains unclear. Radiological features in pretreatment magnetic resonance images may help predict VS pseudoprogression. This study used VS radiological features quantified using an automated segmentation algorithm to predict pseudoprogression after GKRS treatment.
This is a retrospective study comprising 330 patients with VS who received GKRS. After image preprocessing and T2W/contrast-enhanced T1-weighted image (CET1W) image generation, with fuzzy C-means clustering, VSs were segmented into solid and cystic components and classified as solid and cystic. Relevant radiological features were then extracted. The response to GKRS was classified into "nonpseudoprogression" and "pseudoprogression/fluctuation". The Z test for two proportions was used to compare solid and cystic VS for the likelihood of pseudoprogression/fluctuation. Logistic regression was used to assess the correlation between clinical variables and radiological features and response to GKRS.
The likelihood of pseudoprogression/fluctuation after GKRS was significantly higher for solid VS compared with cystic VS (55% vs 31%, P < .001). For the entire VS cohort, multivariable logistic regression revealed that a lower mean tumor signal intensity (SI) in T2W/CET1W images was associated with pseudoprogression/fluctuation after GKRS ( P = .001). For the solid VS subgroup, a lower mean tumor SI in T2W/CET1W images ( P = .035) was associated with pseudoprogression/fluctuation after GKRS. For the cystic VS subgroup, a lower mean SI of the cystic component in T2W/CET1W images ( P = .040) was associated with pseudoprogression/fluctuation after GKRS.
Pseudoprogression is more likely to occur in solid VS compared with cystic VS. Quantitative radiological features in pretreatment magnetic resonance images were associated with pseudoprogression after GKRS. In T2W/CET1W images, solid VS with a lower mean tumor SI and cystic VS with a lower mean SI of cystic component were more likely to have pseudoprogression after GKRS. These radiological features can help predict the likelihood of pseudoprogression after GKRS.
伽玛刀放射外科治疗（GKRS）后前庭神经鞘瘤（VS）假进展的病理生理学仍不清楚。治疗前磁共振图像中的放射学特征可能有助于预测VS假进展。本研究使用自动分割算法量化的VS放射学特征来预测GKRS治疗后的假进展。
这是一项回顾性研究，纳入了330例接受GKRS治疗的VS患者。在图像预处理和生成T2加权/对比增强T1加权图像（CET1W）后，采用模糊C均值聚类将VS分割为实性和囊性成分，并分为实性和囊性。然后提取相关放射学特征。将GKRS的反应分为“无假进展”和“假进展/波动”。采用两比例Z检验比较实性和囊性VS假进展/波动的可能性。采用逻辑回归评估临床变量与放射学特征以及GKRS反应之间的相关性。
与囊性VS相比，实性VS在GKRS后假进展/波动的可能性显著更高（55%对31%，P <.001）。对于整个VS队列，多变量逻辑回归显示，T2W/CET1W图像中较低的平均肿瘤信号强度（SI）与GKRS后假进展/波动相关（P =.001）。对于实性VS亚组，T2W/CET1W图像中较低的平均肿瘤SI（P =.035）与GKRS后假进展/波动相关。对于囊性VS亚组，T2W/CET1W图像中囊性成分较低的平均SI（P =.040）与GKRS后假进展/波动相关。
与囊性VS相比，实性VS更易发生假进展。治疗前磁共振图像中的定量放射学特征与GKRS后假进展相关。在T2W/CET1W图像中，平均肿瘤SI较低的实性VS和囊性成分平均SI较低的囊性VS在GKRS后更易出现假进展。这些放射学特征有助于预测GKRS后假进展的可能性。
