Clinical characteristics of trigeminal neuralgia in a dental hospital

Background

Neurovascular compression (NVC) is a well-known cause of trigeminal neuralgia (TN). However, patients with idiopathic TN (ITN) do not have evidence of NVC on magnetic resonance imaging (MRI), and other patients may remain asymptomatic despite evidence of NVC on MRI. This suggests that there may be additional risk factors for TN development other than NVC. Although epidemiological factors, such as age and sex differences, are useful for understanding the pathophysiology of TN, detailed statistics for each TN subtype are currently unavailable. Therefore, this study aimed to classify patients with TN into the following groups based on data extracted from past medical records: classical TN (CTN), secondary TN, and ITN.

Methods

The characteristics of the groups and their differences were explored.

Results

CTN was more common in women than in men, as previously reported, whereas ITN was more common in men than in women. The ratio of pain sites located on the right side of the face was high in all groups. Patients with CTN were also prone to NVC on the asymptomatic side.

Conclusion

By investigating TN subtype, it may be possible to elucidate the pathophysiology of TN. This would greatly improve treatment outcomes.

Radiofrequency Ablation on Gasserian Ganglion for Idiopathic Trigeminal Neuralgia: A Randomized Controlled Trial

OBJECTIVE

We aimed to evaluate masticatory dysfunction after two different types of ablation on the Gasserian ganglion for the treatment of idiopathic trigeminal neuralgia. We hypothesized that low-temperature plasma radiofrequency ablation (LTP-RFA) was noninferior to radiofrequency thermocoagulation (RFT) with respect to initial efficacy.

METHODS

In the randomized, single-blind, parallel-group, noninferiority trial, 204 participants with idiopathic trigeminal neuralgia were randomly allocated to receive plasma ablation in the LTP-RFA group and radiofrequency ablation in the RFT group in a 1:1 ratio, with random block sizes of four or six. Participants were examined at baseline (T0), on the day of discharge (T1), and at the 6-month follow-up (T2). The primary end point was the clinincal effective rate in the LTP-RFA group compared with that in the RFT group after intervention on the day of discharge. Noninferiority was prespecified at -10%.

RESULTS

The intention-to-treat analysis revealed that the initial efficacy rates were 91.2% in LTP-RFA group and 93.1% in RFT group (rate ratio [RR] = 0.979, 95% confidence interval [CI]: 0.904-1.061, P = 0.795). The difference between the two groups was 1.9% (95% CI: -5.6% to 9.4%), which showed that LTP-RFA demonstrated noninferiority compared with RFT in initial efficacy. Compared with the RFT group, the LTP-RFA group exhibited a significantly greater improvement in the maximum voltage of the masseter muscles with mean differences of 11.40 (95% CI: 10.52 to 12.27, P < 0.001) at T1 and 17.41 (95% CI: 14.68 to 20.13, P < 0.001) at T2, respectively. Similar results were observed for the asymmetry index of occlusion, the maximum voltage of the anterior temporalis, and the activity index of anterior temporalis / masseter muscles. No serious adverse events were observed in either group.

CONCLUSIONS

Compared with the RFT group, noninferior efficacy for pain relief and improvement of masticatory function was revealed in the LTP-RFA group.