The importance of autonomic symptoms in trigeminal neuralgia. Clinical article

Autonomic symptoms can occur in association with the facial pain of trigeminal neuralgia (TN). The distinction between first division (V1) TN and trigeminal autonomic cephalgias, particularly short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT), can be difficult. The goal in this study was to investigate the frequency of autonomic symptoms with TN and to determine their effect on surgical outcome.

The authors sent questionnaires and reviewed the records of 92 patients who underwent surgical procedures for TN to obtain visual analog scale scores for pain before and after surgery and to determine the location of the pain and the presence of autonomic symptoms.

Sixty-seven percent of patients had at least 1 autonomic symptom, and 14% had 4 or more autonomic symptoms associated with their pain. With V1 pain, the most common autonomic symptoms were conjunctival injection, ptosis, and excessive tearing. With pain involving the second division (V2), facial swelling was the most common autonomic symptom. Excessive salivation occurred most often when the pain involved the third division (V3). In patients who underwent microvascular decompression (MVD), visual analog scores for pain showed significantly greater improvement postoperatively in those who had no preoperative autonomic symptoms than in those who reported autonomic symptoms. There was also a significantly greater number of patients who were pain free postoperatively in the group without autonomic symptoms. There were 3 patients with V1 facial pain associated with conjunctival injection and tearing who, in retrospect, fulfilled all the current diagnostic criteria for SUNCT. These patients underwent MVD, during which a vessel was found to compress the trigeminal nerve. Postoperatively, the 3 patients experienced complete and long-lasting pain relief.

The presence of autonomic symptoms in TN correlated with a worse prognosis for pain relief after MVD. First division TN with autonomic symptoms can present identically to SUNCT but can respond to MVD if there is a compressive vessel. Neurosurgeons should be aware of SUNCT, especially in patients with V1 TN and autonomic symptoms, to ensure that all potential medical therapies have been tried prior to surgical treatment.