This study is designed to investigate the effectiveness and safety of 3D-CT-guided percutaneous radiofrequency thermocoagulation for the treatment of tumor-related trigeminal neuralgia.

Approximately 1-13% of trigeminal neuralgia cases are secondary to intracranial tumors, and this condition is referred to as tumor-related trigeminal neuralgia (TRTN). TRTN can result from a lesion affecting any location along the pathway of the trigeminal nerve, such as Meckel's Cave, the posterior fossa, and the cerebellopontine angle. The posterior fossa is the most common location of TRTN, whereas meningioma and epidermoid cysts are the most common pathologies. The goals of TRTN treatment include controlling tumors and relieving pain. Tumor resection is regarded as the most effective treatment, and complete tumor removal is often followed by complete pain remission. However, for patients who cannot undergo the risk of a craniotomy and those with end-stage of malignant tumors or slow-growing benign tumors, surgery may not be the best choice. Conservatively, medication is considered the first-line therapy for relieving pain. However, pharmacology cannot provide satisfactory relief for all patients, and some patients may experience intolerable side effects. For these patients, minimally invasive interventional techniques are preferred. Radiosurgery has been commonly performed for the treatment of TRTN with promising efficacy. However, this intervention is associated with delayed latency of response. Percutaneous radiofrequency thermocoagulation (PRFT) is a low-risk, minimally invasive technique with an acute success rate of 97.6-99%. PRFT remains the most common percutaneous treatment for TN. In addition, this popular procedure may also safely and effectively be repeated if pain recurs. The PRFT procedure involves positioning the radiofrequency (RF) needle at the Gasserian ganglion via the foremen ovale. Suboptimal piercing may lead to unpleasant complications, including cerebrospinal fluid leakage, cranial nerve (VI) palsy and intracranial hemorrhage. Recently, computed tomography (CT) has been demonstrated to be a useful method to identify the optimal position and predict the intraoperative difficulties of the intervention.

Inclusion Criteria:

• age>18 years,
• typical TN symptoms in the same lateral as intracranial tumors,
• uncontrolled symptoms or intolerable side effects of medication,
• pain duration longer than 90 days
• brain magnetic resonance imaging (MRI)confirmed that the trigeminal pain was secondary to intracranial tumors.

Exclusion Criteria:

• patients with infection at the puncture site,
• coagulopathy,
• epilepsy,
• other causes of TN,
• a history of mental disorders or anesthetic drug abuse.

This retrospective study was conducted in Beijing Tiantan Hospital between March 2007 and February 2018. The local ethics committee approved this study and exempted the informed consent before the collection of patient data. We enrolled a total of 38 patients who fulfilled all following criteria: age>18 years; typical TN symptoms in the same lateral as intracranial tumors; uncontrolled symptoms or intolerable side effects of medication; and pain duration longer than 90 days. To confirm that the trigeminal pain was secondary to tumors, brain magnetic resonance imaging (MRI) was performed in advance. Patients with infection at the puncture site, coagulopathy, epilepsy, other causes of TN, a history of mental disorders or anesthetic drug abuse were excluded from this study.