Background & Aims

Recurrent trigeminal neuralgia is one of the most painful disorders, which presents as recurrent, unilateral, brief but severe, electric-shock-like pains of rapid onset and short duration in the distribution of the trigeminal nerve.
The current pain management for TN seems far from optimal. Pharmacologic treatment has systemic side effects, while palliative destructive surgical procedures have complications. In recent decades, several groups have shown the efficacy of repetitive transcranial magnetic stimulation (rTMS) in various facial pain syndromes.
In this study, we present a case of a patient with refractory TN since 2009. She underwent 28 rTMS treatment sessions over 12 months and underwent botulinum toxin A, BT-A treatment in V2 territory. The aim of reporting is to demonstrate further the safety and long-term effect of repeated rTMS stimulation in association to BT-A treatment.

Methods

Single case report
On May 2023, TMS pain treatment protocol began (high-frequency stimulation of the primary motor cortex, opposite to the pain), in association with a depression protocol (stimulation of the PFDL cortex). 10 Hz of M1 contralateral to the painful side in association of rTMS stimulation of the left dorsolateral prefrontal cortex at 10 Hz.
The initial frequency with which she underwent TMS was twice a week.
With the relief of symptoms, the sessions were spaced out to once a week.
On 02/2024, due to another refractory episode of pain in V2 territory, the patient underwent botulinum toxin A, BT-A treatment in V2 territory

Results

Only after the eighth neuromodulation session the patient reported pain relief.
After eight months, due to another refractory episode of pain in V2 territory, the patient underwent botulinum toxin A, BT-A treatment in V2 territory. As side effects, facial asymmetry, which disappeared in 7-8 weeks. After 1 week of the procedure, there was complete remission of pain.
After this period, the patient needed to undergo a major tooth extraction procedure, with two implants, without suffering any worsening of the pain.
During contingencies such as upper respiratory tract infection or when the temperature cools, she reports a slight burning sensation, especially in the nasal region, which causes discomfort when washing her face.
The patient is still very afraid of the recurrence of pain, so she continues to undergo weekly TMS sessions. Currently, she complains of increased pain intensity, maybe due to the lower effect of botulinum toxinas as noticed 3 months after the procedure.

Conclusions

This single-case study showed that 10 Hz rTMS could be an effective adjunct treatment method for patients with refractory TN. As shown in our patient, long-term repeated application of 10 Hz rTMS to M1 and the left dorsolateral prefrontal cortex was not associated with complications. Despite the global improvement in pain due to TMS treatment, there was still a more localized recurrence in the V2 segment. In this way, we proposed Botulinum toxin type A injection as an adjuvant in pain control. Maximum efficacy was noticed between 6 weeks and 3 months after the procedure. Side effects were mostly facial asymmetry after injection, headaches, haematoma, which disappeared in one week.

References

1. Freigang S, Fresnoza S, Lehner C, Jasinskait? D, Ali KM, Zaar K, Mokry M. Twenty-Three Months Repetitive Transcranial Magnetic Stimulation of the Primary Motor Cortex for Refractory Trigeminal Neuralgia: A Single-Case Study. Life (Basel). 2023 Jan 2;13(1):126. doi: 10.3390/life13010126. PMID: 36676075; PMCID: PMC9866023.
2. Rubis A, Juodzbalys G. The Use of Botulinum Toxin A in the Management of Trigeminal Neuralgia: a Systematic Literature Review. J Oral Maxillofac Res. 2020 Jun 30;11(2):e2. doi: 10.5037/jomr.2020.11202. PMID: 32760475; PMCID: PMC7393930.
3. Gatzinsky K, Bergh C, Liljegren A, Silander H, Samuelsson J, Svanberg T, Samuelsson O. Repetitive transcranial magnetic stimulation of the primary motor cortex in management of chronic neuropathic pain: a systematic review. Scand J Pain. 2020 Sep 7;21(1):8-21. doi: 10.1515/sjpain-2020-0054. PMID: 32892189.

Presenting Author

Isabel Chateaubriand

Poster Authors

Isabel Chateaubriand

MD, PhD

Sirio Libanes Hospital

Lead Author

E-mail

Linamara Battistella

MD, PhD, Full Professor

Faculdade de medicina da Universidade de São Paulo

Lead Author

E-mail

Christina Brito MD PhD

Sirio Libanes Hospital

Lead Author

E-mail

Marcel Simis MD PhD

Faculdade de Medicina da Universidade de São Paulo

Lead Author

E-mail

Topics

  • Models: Chronic Pain - Neuropathic