505: Targeted Ultrasound-Guided Mental Nerve Cryoneurolysis in Refractory Perioral Neuropathic Pain

Topic: Clinical Science
Subtopic: Pain category (ICD-11), Chronic neuropathic pain, Developing methodology/technology, Pain in Special Populations , Treatment/management

Background and Aims: Mental neuralgia is a rare but debilitating peripheral neuropathic pain condition characterized by severe, electric shock–like pain in the distribution of the mental nerve, significantly impairing quality of life and daily functioning. Pharmacologic therapy is often limited by inadequate analgesia and intolerable adverse effects, while conventional interventional techniques, such as blind neurolysis or radiofrequency, carry risks of complications and inconsistent outcomes. Ultrasound guidance allows precise localization of the mental foramen and targeted intervention. This study aims to describe the technique and clinical outcome of ultrasound-guided percutaneous cryoneurolysis in refractory mental neuralgia

Methods: A 67-year-old man with refractory left-sided mental neuralgia of seven years’ duration presented with severe electric shock–like pain (NRS 9/10) despite pharmacologic therapy and prior interventional procedures. After informed consent, ultrasound-guided percutaneous cryoneurolysis of the mental nerve was performed. The mental foramen was identified using an 18-MHz high-frequency linear probe. Following local anesthetic infiltration, a 20-gauge cryoprobe was advanced in-plane into the mental foramen under real-time ultrasound guidance. Two freeze–thaw cycles were applied at −78°C for 180 seconds each, separated by active defrosting. The patient was monitored for procedural tolerance and immediate complications.

Results: The procedure was well tolerated without immediate or delayed complications. The patient reported a significant reduction in pain intensity from a baseline NRS score of 9/10 to 3/10 within one week following cryoneurolysis, representing greater than 70% pain relief. Functional improvement was noted, with restoration of sleep and improved participation in daily activities. No sensory deficits beyond the expected localized numbness were observed. At follow-up, sustained analgesia was maintained without the need for additional pharmacologic escalation or repeat intervention. The patient expressed high satisfaction with the outcome and reported meaningful improvement in overall quality of life.

Conclusions: Ultrasound-guided percutaneous cryoneurolysis of the mental nerve appears to be a safe, precise, and minimally invasive treatment option for refractory mental neuralgia. By producing reversible axonal degeneration while preserving connective tissue architecture, cryoneurolysis offers sustained analgesia with low risk of neuroma formation or motor deficit. Real-time ultrasound guidance enhances accuracy and minimizes complications compared to blind or thermal neurolytic techniques. In this case, substantial and durable pain relief was achieved after failure of conventional therapies. This technique may represent a promising alternative for selected patients with peripheral neuropathic facial pain and warrants further evaluation in larger prospective studies.

References: Lloyd JW, Barnard JD, Glynn CJ. Cryoanalgesia: A new approach to pain relief. Lancet. 1976.

Ilfeld BM, et al. Cryoneurolysis and the Treatment of Chronic Pain: Anesthesiology. 2020.

Trescot AM. Cryoanalgesia in interventional pain management. Pain Physician. 2003.

Yang A, et al. Ultrasound-guided mental nerve block techniques. Regional Anesthesia & Pain Medicine.

Sunderland S. A classification of peripheral nerve injuries producing loss of function. Brain. 1951.

Ilfeld BM. Cryoneurolysis for acute and chronic pain. Current Opinion in Anesthesiology.

Cho HK, et al. Pulsed radiofrequency treatment of mental nerve neuralgia. Pain Practice.

Kvarnström A, et al. Mechanisms of cryoneurolysis and Wallerian degeneration.

Presenting Author: Dr Smruti rekha Hota
Submitting Author: Dr SMRUTI REKHA HOTA

Senior Author: Dr Smruti rekha Hota

IASP 2026 Global Year theme of Neuropathic Pain: Yes

• Dr Gautam Das: MD,FIPP - Daradia pain clinic,Kolkata