Scar neuroma infiltration to treat post-surgical first bite syndrome

First bite syndrome (FBS) is an uncommon but often debilitating complication after head and neck surgeries, particularly those that involve or affect the cervical sympathetic chain. FBS is characterized by sudden, severe, and often cramping or electric shock-like pain in the region of the parotid gland, which may become chronic. Current treatment recommendations for FBS-related pain include pharmacologic agents, muscle relaxants, anti-neuropathic and anti-inflammatory agents, oral rehabilitation, and infiltration of anesthetics and botulinum toxin; most patients require systemic analgesics. Although some patients experience a response to pharmacological agents and local infiltration of the salivary glands, a subset develops intractable pain. For some patients, escalating dosages of opiate analgesics are the only management option.

Here, we report a series of five consecutive patients with intractable FBS-related pain that was refractory to conventional treatment. In each case, we found a localized point of mechanical allodynia overlying the surgical scar. Even light stimulation of this focal point elicited the symptoms described during initial mastication.

Identification of the scar neuroma within the surgical field in these patients provided a potential diagnostic and therapeutic target for this condition. We performed a scar infiltration with a mix of 1.75 mL of bupivacaine 0.25% and 0.25 mL of 40 mg/mL triamcinolone. The quality and duration of pain relief following the treatment are described in this report.

All five patients experienced sustained analgesia of over 3 months in duration, with immediate improvement in quality of life because of controlled pain and improved oral feeding.

Scar neuroma infiltration was found to be a minimally invasive, efficient, and cost-effective treatment, and overall patient satisfaction was very high. To our knowledge, this is the first report using this therapy to treat FBS-related pain. The novel approach shows promise in a limited number of patients cases and warrants further investigation.