Low-Risk Trigeminal Neuralgia Nerve Block Treatments
Weekly peripheral trigeminal nerve blocks are a viable treatment option for patients with trigeminal neuralgia.
Trigeminal neuralgia (TN) pain relief may be gained with nerve blocks injections. This is good news for many people suffering from this condition that causes severe facial pain. This article gives you an understanding of the current state of TN treatment and why nerve block therapeutic injections are less risky when compared with surgeries and strong medications.
TN is also known as tic-douloureux.
First, it helps to understand that TN is a condition where the trigeminal nerve, which controls sensation in the face, gets irritated. People seek facial pain specialist to manage it’s intense, sharp, electric-shock-like pain in the facial region. This TN pain is often triggered by things like talking, chewing, or even a light breeze.
Table of Contents
- Low-Risk Trigeminal Neuralgia Nerve Block Treatments
- Trigeminal neuralgia symptoms
- What are Trigeminal Neuralgia Nerve Block Injections?
- What are the Main Benefits of Trigeminal Nerve Blocks?
- Traditional Trigeminal Neuralgia Treatment
- Neurosurgical TN Treatment Options for Suitable Candidates
- What is the Trigeminal Neuralgia Nerve Block Injections Success Rate?
- Trigeminal Neuralgia: Current Approaches and New Interventions
- SUMMARY: Good Candidates for Trigeminal Nerve Block Injections
Trigeminal neuralgia symptoms commonly include:
Sudden, intense pain on one side of the face. The pain can feel like a shock or stabbing, and it can be accompanied by burning, throbbing, numbness, tingling, or dull aching. The pain can affect a small area or spread, and it can occur in the teeth, lower jaw, upper jaw, cheek, forehead, or eyes.
What are Trigeminal Neuralgia Nerve Block Injections?
Nerve block injections are placed at various parts of the nerve to reduce pain. They involve repeated local anesthetic peripheral nerve blocks to anesthetize the trigeminal nerve. These injections are considered a relatively low-risk treatment option that can be used as a bridge to other therapies if needed. This TN treatment approach helps to manage pain while waiting for MVD, or to avoid escalating medication doses.
Trigeminal nerve blocks are a simpler treatment when compared to major surgery like Neurosurgical microvascular decompression (MVD). [1] MVD has its own risks; and anticonvulsants can cause drowsiness, dizziness, and other issues. There are potential risks associated with nerve blocks, such as bleeding, infection, and post-injection discomfortand . These risks are generally low; most patients report that the benefits of rapid pain relief outweigh them.
What are the Main Benefits of Trigeminal Nerve Blocks?
Main benefits:
- Lower risk: Nerve blocks offer a less risky treatment option.
- Rapid relief: Injections near the trigeminal nerve can provide immediate pain relief.
- Lower medication reliance: Nerve blocks can help reduce the reliance on medications, allowing for lower doses and potentially fewer side effects.
- Emergency relief: They are useful to treat acute TN attacks, potentially preventing emergency room visits.
- Duration of relief: The average duration of relief from nerve blocks varies, with the median duration being several hours to a day.
These injections are reported as “helpful” in reducing doses required for symptom control. This in turn can help lower the side effects experienced by patients. Alternatively, second line medications used in combination with these injections may have fewer adverse effects may as opposed to first line medications like carbamazepine and oxcarbazepine.
A Review of Traditional Trigeminal Neuralgia Treatment
Traditionally, pain providers have relied on anticonvulsant medications as the first line of TN treatment.
Their goal is to lower the threshold of action potential generation thereby inhibiting pain signaling in the brain. Trigeminal neuralgia is widely regarded as one of the most painful orofacial pain conditions and can be challenging to treat.[2]
Carbamazepine is considered the most effective anticonvulsant in treating this condition. However, it has potential adverse effects including aplastic anemia and Stevens-Johnson syndrome in genetically susceptible individuals. This triggers a need for constant bloodwork to monitor blood cell counts while a patient is on this medication.
Oxcarbazepine is also commonly used as a anticonvulsant for this disorder with fewer adverse effects but may cause hyponatremia. Meaning, routine bloodwork is also required while on this medication.
Gabapentin, pregabalin, and lamotrigine are also lower risk medication alternatives but still have adverse effects including sedation and unsteadiness which can be problematic in elderly patients. These side effects represent the most common cause for medication discontinuation, as opposed to medication inefficacy [3].
Neurosurgical TN Treatment Options for Suitable Candidates
1. Nerve block
A low-risk surgical option for trigeminal neuralgia includes peripheral nerve blocks or ablation. Typically, fluoroscopy-guided nerve blocks are safely done with the guidance of an observation of the absence of intravascular contrast spread before injecting local anesthetics. Ultrasound helps the physician see adjacent tissues, bony structures, and vessels. It guides the needle trajectory to the target region without radiation exposure.
Performing the block under imaging guidance can help prevent complications. Maxillary nerve blocks via the pterygopalatine fossa are successfully performed using ultrasound even in deep trigeminal nerves.
2. Microvascular decompression
Microvascular decompression (MVD) is an operation that can assist in reducing trigeminal neuralgia pain without intentionally damaging the trigeminal nerve. The procedure relieves the pressure placed on the trigeminal nerve by blood vessels that are touching the nerve or are wrapped around it. This is accomplished by separating the vessel that is negatively affecting the trigeminal nerve.
MVD is a surgical option for trigeminal neuralgia only if an MRI shows a blood vessel compressing the nerve. In many trigeminal neuralgia cases, there is no evidence of such vascular compression and so the patient would not be a candidate for a procedure to separate the offending vessel from the trigeminal nerve.
Other Factors for in deciding if MVD surgery is the right choice:
- Age: Older patients may have a higher risk of complications during surgery.
- Overall Health: Surgery is riskier for people with other health conditions.
- Weighing additional neurosurgery risks: The decision to have MVD surgery is complex. Doctors and patients carefully consider the potential benefits and adverse effects such as facial sensory loss and/or anesthesia dolorosa
“It provides the longest lasting relief, with some studies suggesting that pain returns in about 3 out of 10 cases within 10 to 20 years of surgery.” – Trigeminal Neuralgia Treatment
3. Gamma knife
Gamma Knife (GK) radiosurgery of the trigeminal nerve can be used to treat refractory facial pain in TN. Complete pain relief is achieved in 70% of patients, which is maintained in 40-55% at three years, and in 25% at 10 years. [4] It may be useful as a potential constraint for bothersome numbness.[5]
4. Glycerol rhizotomy
Percutaneous glycerol rhizotomy (PGR) is widely considered a safe and effective minimally invasive procedure for treating trigeminal neuralgia. Treatment involves injecting a small amount of sterile glycerol into the trigeminal nerve to disrupt pain signals. PGR has a 92.1% success rate for improving facial pain, and can be more beneficial for the elderly. However, Glycerol injections are associated with a high recurrence rate. [6]
5. Balloon compression
Balloon compression, also known as percutaneous balloon compression (PBC), is a medical procedure that compresses the trigeminal ganglion to treat trigeminal neuralgia. The intent is to disrupt the pain signals from reaching the brain. [7]
Let’s go back to why we might recommend the TN nerve block treatment option.
What is the Trigeminal Neuralgia Nerve Block Injections Success Rate?
A 6 July, 2022 Peripheral Nerve Blocks as a Treatment Modality for Trigeminal Neuralgia study along with Bradley Eli, DMD MS includes the following positive success rate findings.
| Patient | Age (years) | Location of Blocks | Duration of relief from each block | Percentage of reported relief after blocks |
|---|---|---|---|---|
| 1 | 83 | Right ASA, MSA, PSA | 2 hours | 90% |
| 2 | 53 | Right ASA, MSA, PSA, IAN, LB, mental | 4 hours | 80% |
| 3 | 85 | Left IAN, LB | 72 hours | 40% |
| 4 | 65 | Left ASA, MSA, PSA, IAN, LB, mental | 72 hours | 100% |
| 5 | 84 | Left ASA, MSA, PSA | 96 hours | 75% |
| Average | 74 | — | 49.2 hours | 77% |
For context, each of the study participants were concurrently taking or had previously taken prescribed anticonvulsant medication to help manage TN pain. Study findings signal that conventional TN treatments can benefit from supplemental nerve block injections to improve outcomes.
The above study was performed analyzing the pain levels and symptomatic relief obtained after completing a weekly series of trigeminal nerve block injections in five patients with trigeminal neuralgia. No major adverse reactions were noted following the nerve blocks. Participants reported occasional, mild discomfort at the injection site and post injection soreness.
Jin Young Lee made a key summary statement in his National Institute of Health 21 Aug. 2023 article.
“A nerve block plays an important role in the diagnosis, prognosis, and treatment of pain by intercepting the vicious cycle of pain, blocking sympathetic nerves, expanding vessels in the lesion area, and improving local blood flow. Peripheral interventions involve blocking or destroying a portion of the trigeminal nerve distal to the Gasserian ganglion.” – Non-Surgical Treatments of Trigeminal Neuralgia from the Perspective of a Pain Physician: A Narrative Review
What are Nerve Block Injections Used For?
Potential uses of nerve block injections:
- Acute pain: Sudden, severe pain.
- Chronic pain: Long-lasting pain.
- Inflammation: Swelling and irritation.
The goal of these injections is to repeatedly anesthetize the distribution of trigeminal nerve pain. The anesthetic can function like a temporary roadblock, slowing down or stopping the flow of those pain signals. By doing this repeatedly, your nerve has a chance to calm down and reduce painful episodes associated with trigeminal neuralgia.
Who may not be a good candidate for trigeminal nerve block?
People with the following medical conditions may not be a suitable TN nerve block candidate:
- Patients with an infection at the injection site.
- If the patient has a bleeding disorder.
- An individual who has experienced previous neural problems in the area of the nerve being injected.
Trigeminal Neuralgia: Current Approaches and New Interventions
- New treatments: There are newer treatments available for TN, such as percutaneous radiofrequency ablation and gamma knife radiosurgery. These options may be considered alternatives to MVD or nerve blocks.
- Steroids: Steroid injections are often used in combination with anesthetics in TN nerve blocks.
- Additional research: Our facial pain specialists continue to engage in ongoing research to continually refine our understanding of TN and its treatment.
Future studies may explore different types of injections along with testing different anesthetics or steroids. Overall, nerve blocks are a promising option for managing trigeminal neuralgia. More research is needed to understand their full potential.
SUMMARY: Good Candidates for Trigeminal Nerve Block Injections
It’s crucial to consult with a healthcare professional for personalized advice and treatment options. We can help evaluate the risks and benefits of different TN treatments based on your individual needs and medical history. We will assess your individual situation and help you make the best decision for your health.
References
[1] Imran Noorani, et al, “Comparison of first-time microvascular decompression with percutaneous surgery for trigeminal neuralgia: long-term outcomes and prognostic factors,” 22 Mar. 2021, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8116280/[2] Nidhi Shankar Kikkeri, et al, “Trigeminal Neuralgia,” 3 March 2024, https://www.ncbi.nlm.nih.gov/books/NBK554486/
[3] Maarbjerg , Stine, et al. “Trigeminal Neuralgia – Diagnosis and Treatment,” 11 Jan. 2017, https://pubmed.ncbi.nlm.nih.gov/28076964/
[4] AI Yang, et al, “Gamma Knife radiosurgery for trigeminal neuralgia provides greater pain relief at higher dose rates,” Jan. 2022, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9489081/
[5] Ronald E. Warnick, et al, “The relevance of biologically effective dose for pain relief and sensory dysfunction after Gamma Knife radiosurgery for trigeminal neuralgia: an 871-patient multicenter study,” 16 Feb. 2024, https://thejns.org/view/journals/j-neurosurg/141/2/article-p461.xml
[6] Mayo Clinic, “Trigeminal Neuralgia Diagnosis and Treatment,” 28 Dec. 2023, https://www.mayoclinic.org/diseases-conditions/trigeminal-neuralgia/diagnosis-treatment/drc-20353347
[7] Bayron Valenzuela Cecchi, et al, “Percutaneous Balloon Compression for the Treatment of Trigeminal Neuralgia: A Review of 10 Years of Clinical Experience,” 15 Aug. 2023, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10505044/