Factors Associated With Long-Term Risk of Recurrence After Percutaneous Radiofrequency Thermocoagulation of the Gasserian Ganglion for Patients With Trigeminal Neuralgia Involving the Ophthalmic Division: A Retrospective Study

Proximal trigeminal nerve atrophy is associated with favourable outcomes and persistent facial numbness following percutaneous balloon compression for primary trigeminal neuralgia

OBJECTIVE

Whether nerve atrophy can affect the prognosis of primary trigeminal neuralgia (PTN) patients undergoing percutaneous balloon compression (PBC) remains unclear. This study aimed to determine the association between nerve characteristics observed on preoperative magnetic resonance imaging (MRI) and PBC outcomes.

METHODS

Between January 2019 and December 2022, a cohort of 58 patients with unilateral PTN treated with PBC were analysed retrospectively and included in this study. The relationship between MRI findings, including the proximal and distal nerve cross-sectional areas (CSAs), and favourable pain outcomes (BNI Grades I-III) was analysed through Kaplan‒Meier analysis.

RESULTS

After a mean follow-up period of 23.8 ± 13.0 months (range, 6-50 months), 48 (82.8%) patients with PTN were pain free with or without medication. A smaller proximal CSA ratio (proximal CSA of the affected nerve/proximal CSA of the unaffected nerve) was significantly associated with favourable outcomes. The Kaplan-Meier survival analysis showed that patients with proximal nerve atrophy (proximal CSA ratio ≤ 87% after receiver operating characteristic curve analysis) had a higher estimated 4-year probability of maintaining a favourable outcome than those without nerve atrophy (94.4% vs. 30.8%, p = 0.005). In addition, patients with proximal nerve atrophy were more likely to suffer from postoperative persistent facial numbness.

CONCLUSIONS

Proximal nerve atrophy is correlated with both favourable outcomes and persistent facial numbness following PBC. Prospective studies are required to determine the optimal duration and pressure of balloon compression in relation to the proximal CSA ratio to achieve better pain outcomes and less facial numbness.

Effects of the MR-DTI Characteristics of the Trigeminal Ganglion Target on Radiofrequency Treatment in Patients with Trigeminal Neuralgia: A Retrospective Observational Clinical Study

Background. In the percutaneous treatment of trigeminal neuralgia (TN), the difficulty in accessing the foramen ovale (FO) has been widely recognized. However, the most efficient percutaneous treatment target is the so-called trigeminal ganglion target (TGT). We propose that the TGT in a puncture can be identified by magnetic resonance diffusion tensor imaging (MR-DTI). Objectives. To observe the effect of the characteristics of the TGT as detected by MR-DTI on percutaneous stereotactic radiofrequency rhizotomy (PSR) in TN patients. Methods. In our observational study, we preoperatively performed MR-DTI and/or 3D-CT for 48 TN patients, analyzed the characteristics of the TGT and/or FO, and designed appropriate surgical schemes for producing an accurate PSR trajectory according to these characteristics. The position and size of the TGT aided in adjusting the puncture angle and guiding the approach. Then, we successfully performed a customized PSR guided by the characteristics of the FO or TGT. During the postoperative and follow-up periods, we assessed the effect of treatment with pain scores and MR-DTI findings. Results. The characteristics of the TGT vary from patient to patient. We performed PSR with a single puncture guided by MR-DTI and 3D-CT in 16 patients, and only one patient required three punctures. All three of these punctures reached the FO target, as confirmed by intraoperative C-arm X-ray. We finally reached the TGT successfully after 2 additional attempts, confirming that the probe reached the TGT that accurately covered the pain territory with an electrophysiology test. The characteristics of the TGT were negatively correlated with the number of PSR punctures. Fewer complications occurred for PSRs guided by the TGT than for PSRs guided by the FO. Conclusions. The characteristics of the TGT are correlated with the number of punctures in the PSR. The application of MR-DTI for detecting the size of the TGT is an important step in predicting the difficulty of puncture. The PSR approach can be guided by the TGT and FO for TN patients who present with multiple adverse factors and thus may be beneficial in reducing the number of complications.

Long-term outcomes and predictors of percutaneous radiofrequency thermocoagulation of Gasserian ganglion for maxillary trigeminal neuralgia: a retrospective analysis of 1070 patients with minimum 2-year follow-up

OBJECTIVE

To estimate long-term efficacy and safety for maxillary trigeminal neuralgia (TN) using radiofrequency thermocoagulation (RFT) targeted on Gasserian ganglion, and to identify the factors which may influence outcomes after procedure.

METHODS

From 2006 to 2019, 1070 patients underwent RFT for the treatment of medically refractory maxillary TN was included. All patients were followed up for at least 2 years. Outcomes and complications were recorded and analysed. Logistic regression analysis was employed to identify risk factors of long-term pain recurrence. Prognostic value was calculated from receiver-operating characteristic curve (ROC).

RESULTS

Longitudinal analysis was taken place for 97 non-responders (9.1%) with ineffective pain relief, 253 responders (23.6%) with pain recurrence and 720 responders (67.3%) without pain recurrence. The median pain-free survival (PFS) was 112.0 months (95% CI: 107.5, 116.5). The pain-free rates were 89.9% (95% CI: 88.0-91.8%) at 1 year, 83.8% (95% CI: 81.5-86.1%) at 2 years, 75.4% (95% CI: 72.7-78.1%) at 5 years and 70.2% (95% CI: 67.4-73.0%) at 10 years. Atypical facial pain (HR = 5.373, 95% CI: 2.623-11.004, p < .001), previous facial numbness (HR = 5.224, 95% CI: 3.107-8.784, p < .001) and poor initial response to medication (HR = 3.185, 95% CI: 2.087-4.860, p < .001) were independently associated with long-term pain recurrence. Patients with prognostic index (PI) > 0.25 were identified as high-risk for recurrent TN (HR = 5.575, 95% CI: 3.991-7.788, p < .001). New and worsen facial hypoesthesia was recorded in 77.9% of patients corresponding with BNI score II-IV, and 18.7% reported improved sensation. Severe complication incidence including troublesome dysesthaesia, keratitis and masseter weakness was higher in 80 °C group.

CONCLUSIONS

Favourable outcomes were achieved in terms of long-term pain relief and complications rate after RFT for maxillary TN. Patients with typical facial pain, normal facial sensation, and good initial response to medications may have favourable long-term outcomes.Key messagesThis is a retrospective analysis of radiofrequency thermocoagulation (RFT) targeted on Gasserian ganglion for the treatment of maxillary trigeminal neuralgia (TN) during long-term follow-up. Recurrence-free survival among a large sample was assessed and risk factors associated with long-term pain recurrence was identified. It has been verified that inadvertent damage of ophthalmic and mandibular division causes ophthalmic and masticatory complications. Therefore, a more precise needle tip position and thermocoagulation using a relatively low temperature was recommended.

Identification of Foramen Ovale With H-Figure Fluoroscopic Landmark Improves Treatment Outcomes in Idiopathic Trigeminal Neuralgia

BACKGROUND

Because it is traditionally difficult and time-consuming to identify the foramen ovale (FO) with fluoroscopy, we recently developed the H-figure method to acquire fluoroscopic view of FO with shorter procedure time and less radiation. However, the impact of such an H-figure approach on the clinical outcomes of trigeminal ganglion radiofrequency thermocoagulation (RFT) in treating idiopathic trigeminal neuralgia (ITN) remains unclear.

METHODS

In a 12-month follow-up retrospective cohort study, patients with ITN had fluoroscopy-guided RFT of trigeminal ganglion via either classic approach (n = 100) or H-figure approach (n = 136) to identify FO. Data of continuous variables were analyzed with a Shapiro-Wilk test for normality and subsequently with a Mann-Whitney test, and the binary data were analyzed with a χ 2 test. The primary outcome was the facial pain measured by a Visual Analog Scale (VAS) 1 year after the treatment. The secondary outcomes included the quality of the fluoroscopic FO views, the threshold voltage to provoke paresthesia, the procedure time, the number of fluoroscopic images, and the facial numbness VAS.

RESULTS

Compared with the classic approach group, the H-figure approach group was associated with better long-term pain relief after the procedure, with significantly fewer patients had pain 3 months (6.6% vs 17.0%, P = .012) and 12 months (21.3% vs 38.0%, P = .005) after the procedure, and among patients who had pain after the procedure, patients in the H-figure group had significantly less pain 6 months after the procedure (VAS median [interquartile range (IQR)]: 3 [2-6] vs 6 [4-7], P < .001). Moreover, compared to the classic approach, the H-figure approach provided better fluoroscopic view of FO, lower threshold voltage to elicit paresthesia (median [IQR]: 0.2 [0.2-0.3] vs 0.4 [0.4-0.5] V, P < .0001), with shorter procedure time (median [IQR]: 7.5 [6.0-9.0] vs 14.0 [10.0-18.0] min, P < .0001), and required fewer fluoroscopic images (median [IQR]: 4.0 [3.0-5.0] vs 8.0 [6.0-10.0], P < .0001).

CONCLUSIONS

RFT of the trigeminal ganglion using the H-figure approach is associated with superior longer term clinical pain relief than the classic approach in treating ITN.

Effectiveness, Safety, and Predictors of Response to 5% Lidocaine-Medicated Plaster for the Treatment of Patients With Trigeminal Neuralgia: A Retrospective Study

BACKGROUND

Whether 5% lidocaine-medicated plaster (LMP) is a valuable therapeutic option for the treatment of trigeminal neuralgia (TN) is worth exploring. If LMP is proven effective for TN, positive predictors of the analgesic effects of LMP warrant further investigation.

OBJECTIVE

To evaluate the efficacy and safety of LMP for the treatment of TN, and to explore the predictive factors for the treatment efficacy of LMP.

METHODS

This is a retrospective and observational study. We analyzed the efficacy of LMP for the treatment of TN between March 2019 and January 2022. The follow-up time was approximately 2 weeks, 1 month, 2 months, and 3 months after LMP treatment. The LMP response was considered the Barrow Neurological Institute (BNI) score of I to III and an improvement in BNI of at least I grade from pretreatment baseline. Univariable and multivariable logistic analyses were performed to identify the predictive factors for LMP response.

RESULTS

A total of 103 patients were included and analyzed in this study. LMP was effective in some TN patients, with an efficacy rate of 21.4%, 21.4%, 18.4%, and 16.5% after 2 weeks, 1 month, 2 months, and 3 months of LMP treatment, respectively. The overall adverse event rate associated with LMP was 5.8%, and the reported adverse events were all skin reactions. Facial trigger points (odds ratio [OR] = 0.25, 95% confidence interval [CI] = 0.07-0.86, P = 0.03) and a lower BNI score (OR = 0.37, 95% CI = 0.07-0.87, P = 0.01) were identified as potential predictors for initial efficacy (2-week follow-up) of LMP treatment.

CONCLUSIONS AND RELEVANCE

LMP has been shown to provide effective and sustained analgesia in some TN patients with minimal risk of systemic adverse reactions. Patients with facial trigger points and mild to moderate pain are more likely to benefit from LMP treatment. Our data suggest that LMP may be an effective treatment option for patients with the aforementioned characteristics of TN.

Long-term Recurrence-free Survival and Complications of Percutaneous Balloon Compression and Radiofrequency Thermocoagulation of Gasserian Ganglion for Trigeminal Neuralgia:A Retrospective Study of 1313 Cases

OBJECTIVE

To estimate long-term recurrence, complications after percutaneous balloon compression (PBC) and radiofrequency thermocoagulation (RFT) of gasserian ganglion among a large sample of patients with trigeminal neuralgia (TN) during a long-term follow-up.

METHODS

A retrospective analysis of 1313 patients undergoing PBC or RFT for the treatment of TN was conducted from 2006 to 2020. Recurrence-free survival (RFS) was assessed by Kaplan-Meier method. Complications including facial numbness, corneal reflex decrease and masseter weakness were also estimated.

RESULTS

For patients who received first initial PBC and RFT, the median RFS was 130.1 months (95%CI: 124.4, 135.9) and 123.3 months (95%CI: 117.6, 128.9) in PBC and RFT group with log-rank p=0.108. The RFS rate was respectively 90.6% (95%CI: 88.1%-93.3%) and 91.4% (95%CI: 89.1%-93.7%) at 1 year, 84.6% (95%CI: 81.4%-87.8%) and 83.3% (95%CI: 80.3%-86.3%) at 3 years, 81.5% (95%CI: 78.1%-85.0%) and 78.6 % (95%CI: 75.2%-81.9%) at 5 years, 71.5% (95%CI: 67.5%-75.5%) and 64.8% (95%CI: 61.0%-68.7%) at 10 years in two groups. No significant difference was observed in facial numbness degree between two groups after procedure. Compared with PBC group, ophthalmic complication prevalence was higher in RFT group (9.6%) (p=0.001). However, masseter weakness incidence was lower (10.7%) than that in PBC group (24.0%) with p<0.001.

CONCLUSIONS

Patients with TN seemed to attain similar long-term benefit from PBC and RFT, especially in elderly. However, in order to reduce postoperative complications, PBC provided a safer and alternative for treating TN involving ophthalmic division, whereas RFT could be employed as a preferred regimen for maxillary and mandibular TN.