Novel theory about radiosurgery's action mechanisms on trigeminal ganglion for idiopathic trigeminal neuralgia: Role of the satellite glial cells

Predictive value of foramen ovale size on pain recurrence after percutaneous balloon compression

OBJECTIVES

Primary trigeminal neuralgia (PTN) is a common cranial nerve disease in neurosurgery, which seriously endangers the physical and mental health of patients. Percutaneous balloon compression (PBC) has become an effective procedure for the treatment of PTN by blocking pain conduction through minimally invasive puncture. However, the recurrence of facial pain after PBC is still a major problem for PTN patients. Intraoperative balloon shape, pressure and compression time can affect the prognosis of patients with PBC after surgery. The foramen ovale size has an effect on the balloon pressure in Meckel's lumen. This study aims to analyse the predictive value of foramen ovale size for postoperative pain recurrence of PBC by exploring the relationship between foramen ovale size and postoperative pain recurrence of PBC.

METHODS

A retrospectively analysis was conducted on the clinical data of 60 patients with PTN who were treated with PBC in Department of Neurosurgery, Affiliated Hospital of Chengde Medical College from November 2018 to December 2021. We followed-up and recorded the Barrow Neurological Institute (BNI) pain score at 1, 3, 6 and 12 months after operation. According to the BNI pain score at 12 months after surgery, the patients were divided into a cure group (BNI pain score I to Ⅱ) and a recurrence group (BNI pain score Ⅲ to Ⅴ). The long diameter, transverse diameter and area of foramen ovale on the affected side and the healthy side of the 2 groups were measured. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were used for analysis the relationship between the recurrence of pain and the long diameter, transverse diameter, area of foramen ovale on the affected side, and aspect ratio, transverse diameter ratio, area ratio of foramen ovale on the affected side to healthy side in the 2 groups.

RESULTS

At the end of 12 months of follow-up, 50 (83.3%) patients had pain relief (the cured group), 10 (16.7%) patients had different degrees of pain recurrence (the recurrence group), and the total effective rate was 83.3%. There were no significant differences in preoperative baseline data between the 2 groups (all P>0.05). The long diameter of foramen ovale on the affected side, the long diameter ratio and area ratio of foramen ovale on the affected/healthy side in the cured group were significantly higher than those in the recurrence group (all P<0.05), and there were no significant differences in the transverse diameter and area of foramen ovale on the affected side and the transverse diameter ratio of foramen ovale on the affected/healthy side between the 2 groups (all P>0.05). The ROC curve analysis showed that the AUC of the long diameter of foramen ovale on the affected side was 0.290 (95% CI 0.131 to 0.449, P=0.073), and the AUC of aspect ratio of foramen ovale on the affected side to healthy side was 0.792 (95% CI 0.628 to 0.956, P=0.004). The AUC of area ratio of foramen ovale on the affected side to healthy side was 0.766 (95% CI 0.591 to 0.941, P=0.008), indicating that aspect ratio and area ratio of foramen ovale on the affected side to healthy side had a good predictive effect on postoperative pain recurrence of PBC. When aspect ratio of foramen ovale on the affected side to healthy side was less than 0.886 3 or area ratio of foramen ovale on the affected side to healthy side was less than 0.869 4, postoperative pain recurrence was common.

CONCLUSIONS

Accurate evaluation of the foramen ovale size of skull base before operation is of great significance in predicting pain recurrence after PBC.

Trigeminal ganglion itself can be a viable target to manage trigeminal neuralgia

Excruciating trigeminal neuralgia (TN) management is very difficult and severely affects the patient's quality of life. Earlier studies have shown that the trigeminal ganglion (TG) comprises several receptors and signal molecules that are involved in the process of peripheral sensitization, which influences the development and persistence of neuropathic pain. Targeting TG can modulate this sensitization pathway and mediate the pain-relieving effect. So far,there are few studies in which modulation approaches to TG itself have been suggested so far. "Trigeminal ganglion modulation" and "trigeminal neuralgia" were used as search phrases in the Scopus Index and PubMed databases to discover articles that were pertinent to the topic. In this review, we address the role of the trigeminal ganglion in TN and underlying molecules and neuropeptides implicated in trigeminal pain pathways in processing pathological orofacial pain. We also reviewed different modulation approaches in TG for TN management. Furthermore, we discuss the prospect of targeting trigeminal ganglion to manage such intractable pain.