Disclosures: Brittany A. Mays, MD: No financial relationships or conflicts of interest

Case Diagnosis: A 46 year old female with trigeminal neuralgia (TN) status post surgical resection and radiation for recurrent multifocal pleomorphic adenoma of the left parotid.

Case Description: Patient presented with chronic left sided facial itching associated with intermittent left sided facial pain in the V3 distribution. Symptoms began 4 years ago following surgical revision and adjuvant radiation of a near total left parotidectomy for recurrent multifocal pleomorphic adenoma. Her itching was exacerbated by light touch, eating salty or sweet foods, while her pain symptoms worsened with laying directly on the affected side, and teeth brushing. She failed management with topical lidocaine and gabapentin. She tried carbamazepine without relief of itching but improved pain; it was discontinued due to increased appetite. Patient underwent left V3 nerve block using a mixture of bupivacaine 0.5% and dexamethasone 10mg under ultrasound guidance.

Setting: Pain CenterAssessment/

Results: Following the left V3 nerve block, patient reported significant symptomatic relief starting 1-2 days following the procedure. She received 6 weeks of itching relief, but the itching gradually returned. At the time of her 3-month follow-up, she continued to have ongoing pain relief.

Discussion: While known complications after parotidectomy include facial nerve palsy, greater auricular nerve hypoesthesia, and Frey syndrome, TN is rare. TN is characterized by recurrent paroxysms of unilateral pain in the distribution of one or more divisions of the trigeminal nerve, with V3 being affected in more than 70% of cases. Lesions in the trigeminal nerve are best known to cause neuropathic pain, but these lesions can result in the rare presentation of neuropathic itch syndrome.

Conclusion: This case supports the use of trigeminal nerve blocks not only for neuropathic pain relief, but also for neuropathic itch syndrome associated with TN. To our knowledge, this is the first reported case of neuropathic itch associated with TN following parotidectomy and adjuvant radiation therapy.

Level of Evidence: Level V

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PM&R Meeting Abstracts - https://pmrjabstracts.org/abstract/successful-v3-nerve-block-for-neuropathic-itch-associated-with-trigeminal-neuralgia-secondary-to-recurrent-multifocal-pleomorphic-adenoma-of-the-left-parotid-a-case-report/