Borkar Sachin Anil, Garg Ajay, Mankotia Dipanker Singh, Joseph S Leve, Suri Ashish, Kumar Rajinder, Kale Shashank Sharad, Sharma Bhawani Shankar
Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India.
Department of Neuroradiology, All India Institute of Medical Sciences, New Delhi, India.
Neurol India. 2016 Sep-Oct;64(5):965-70. doi: 10.4103/0028-3886.190270.
Resection of large Vestibular Schwannomas (VSs) can be associated with postoperative facial nerve injury. Diffusion-based tractography has emerged as a powerful tool for three-dimensional imaging and reconstruction of white matter fibers; however, tractography of the cranial nerves has not been well studied. In this prospective study, we aim to predict the position of facial nerve in large VSs (>3 cm) using Diffusion Tensor Imaging (DTI) tractography and correlate it with the intraoperative finding of the position of facial nerve.
Twenty patients with a large VS (>3 cm) undergoing surgery were subjected to preoperative DTI to predict the position of the facial nerve in relation to the tumor. The surgeon was blinded to the results of the preoperative DTI tractography. A comparative analysis was then made during operation. The location of the facial nerve in relation to the tumor was recorded during surgery using facial nerve stimulator.
Of the 20 patients who underwent DTI tractography, it was not possible to preoperatively identify facial nerve in one patient. In another patient, although DTI tractography predicted the position of facial nerve, it was not identified intraoperatively. In the remaining 18 patients, DTI tractography accurately predicted the facial nerve position. The predicted position was in synchronization with the intraoperative facial nerve position in 16 patients (89% concordance). It was discordant in two patients (11%), but this was not found to be statistically significant (P = -0.3679).
This study validates the reliability of facial nerve DTI-based fiber tracking for prediction of the facial nerve position in patients with large VSs. The reliable preoperative visualization of facial nerve location in relation to the VS will allow surgeons to plan tumor removal accordingly and may increase the safety of surgery.
大型前庭神经鞘瘤（VSs）切除术后可能会出现面神经损伤。基于扩散的纤维束成像已成为一种用于白质纤维三维成像和重建的强大工具；然而，颅神经的纤维束成像尚未得到充分研究。在这项前瞻性研究中，我们旨在使用扩散张量成像（DTI）纤维束成像预测大型VSs（>3 cm）中面神经的位置，并将其与术中面神经位置的发现相关联。
20例接受大型VSs（>3 cm）手术的患者在术前接受DTI检查，以预测面神经相对于肿瘤的位置。外科医生对术前DTI纤维束成像的结果不知情。然后在手术过程中进行对比分析。在手术期间使用面神经刺激器记录面神经相对于肿瘤的位置。
在接受DTI纤维束成像的20例患者中，有1例患者术前无法识别面神经。在另1例患者中，尽管DTI纤维束成像预测了面神经的位置，但术中未识别出该神经。在其余18例患者中，DTI纤维束成像准确预测了面神经的位置。预测位置与16例患者（89%一致）的术中面神经位置同步。在2例患者（11%）中不一致，但未发现具有统计学意义（P = -0.3679）。
本研究验证了基于DTI的面神经纤维追踪在预测大型VSs患者面神经位置方面的可靠性。术前可靠地显示面神经相对于VS的位置将使外科医生能够据此规划肿瘤切除，并可能提高手术安全性。
