Abstract
Introduction
Since the first reports by Sjaastad et al., SUNCT syndrome has received more attention (1, 2). SUNCT is defined as Shortlasting, Unilateral, Neuralgiform headache attacks with Conjunctival injection and Tearing (3, 4). Little more than 30 cases have been reported (3, 5–13). Only a few of them had symptomatic forms of SUNCT (6, 14–16). Other forms of short-lasting headache syndromes (e.g. trigeminal neuralgia, cluster headache, paroxysmal hemicrania) may have a differential diagnosis (4, 17). The pathophysiology of SUNCT syndrome still remains unclear (8, 14, 18). The trigeminal nerve and some neuropeptides may be involved (19). Goadsby and Lipton proposed classifying SUNCT syndrome within the group of trigeminal autonomic cephalalgias (4). The lack of effectiveness of most therapeutic regimens commonly used in the treatment of headache has been described (20). Due to the limited experiences with this syndrome and its treatment options, every new case and therapeutic trial might be helpful in understanding the syndrome.
Case report
A 69-year-old man presented with a 9-year history of daily neuralgic pain attacks of 30–60 s duration, a frequency of 20–80 attacks per day and an intensity of 10 on a numeric rating-scale (NRS 0: no pain; NRS 10: most severe pain). The attacks were on the right retro-orbital side and had a burning and stabbing character. They were associated with marked tearing, moderate ptosis, miosis, redness of the ipsilateral eye and rhinorrhoea. Attacks were triggered by rotary neck movement, talking and chewing. The patient reported that the pain had spread slightly to the contralateral side during the last year. In the first years he had spontaneous remissions – lasting no longer than 4 weeks – in between the pain periods. Subsequently the frequency of pain attacks had increased within the last year and the patient did not have 1 day free of pain attacks. The pain syndrome worsened and the patient reported a continuous pain (NRS 10) in between the attacks, located in the same area.
The neurological examination was repeatedly normal, except for a mild allodynia in the painful area. The magnetic resonance imaging and computer tomography demonstrated signs of a mild vascular encephalitis and a mild sinusitis maxillaris of the left side requiring no treatment. Electroencephalography, sensory evoked potentials of the trigeminal nerve and Doppler ultrasonography of the extracranial vessels were normal. There was no evidence of glaucoma.
The patient's psychiatric history was unremarkable, with the exception of one episode when his daughter died. The patient now showed no signs of post-traumatic stress disorder according to DSM-IV criteria, nor signs of depressive or other mood disorders.
He had been treated with sumatriptan, prednisolone, indomethacin (300 mg per day), verapamil, carbamazepine (maximum dose 3000 mg per day), vitamin B 12, diazepam and oxygen-insufflation without any benefit. At the time of admission to our pain clinic he had been treated with a combination of carbamazepine (800 mg per day), tilidin/naloxone (250 mg per day), verapamil (240 mg per day) and lithium (900 mg per day), the latter leading to severe tremor of the upper extremities. With this regimen, pain attacks were reduced slightly in intensity, though not in frequency.
A series of nerve blocks of the right superior cervical ganglion was initiated. We performed these blocks with 0.03 mg buprenorphine in 3 ml natriumhydrochlorid 0.9% each. With the first block, pain intensity of continuous pain was reduced from NRS 10 to NRS 4, lasting for more than 12 hours. The pain attacks diminished completely. After this initial success, we performed a series of seven blocks within a 2-month period (Fig. 1). At the end of the blockade series, the patient reported being free of continuous pain as well as pain attacks. The tremor of the upper extremities diminished after reducing the daily dose of lithium to 330 mg. A further reduction of the analgesic medication led to an immediate recurrence of pain attacks, so that drug therapy with carbamazepine, verapamil, tilidin/naloxone and lithium had to be continued. The patient has been pain-free during the subsequent 16-month follow-up period.
Protocol of the pain intensity before and after injection of 0.03 mg buprenorphine at the superior cervical ganglion. Different levels of pain intensity before the injection of the first (▲), second (○) and fifth (▪) block are documented. Arrow marks the time of injection. The patient is asked to rate the pain intensity on a visual analogue scale (VAS) at 1, 5, 10, 20, 60 and 120 min after the injection.
Discussion
The symptoms of our patient over the last 9 years showed characteristic clinical features of SUNCT syndrome. Extensive neurological and radiological examination excluded a symptomatic SUNCT syndrome, as has been described in some cases (6, 14, 16). Several drug trials failed in our patient. Unlike chronic paroxysmal hemicrania, the pain was refractory to indomethacin. Most treatment trials described have not been effective in SUNCT syndrome (4, 20). There was a slight improvement with valproate, carbamazepine, sumatriptan, prednisone, nifedipine and lamotrigine in a few patients (4, 20, 21). Verapamil and omeprazol have been reported to worsen the pain syndrome (4). There has been no effect with local anaesthetic blocks (20). A local opioid block of the superior cervical ganglion has not been described for the treatment of SUNCT. Mays et al. first described the injection of morphine at the stellate ganglion in patients with upper quadrant sympathetic-type pain and buprenorphine was used for the first time by Sprotte (22, 23).
Maier introduced the terminus of the local opioid analgesia at the ganglion (GLOA = Ganglionäre Lokale OpioidApplikation) in 1996 and described the GLOA extensively (24). The mechanism of action is not yet clearly understood; however, there is no sympatholytic or systemic effect (22, 24). Maier recommended GLOA at the superior cervical ganglion as a diagnostic and therapeutic tool for different pain syndromes of the head or facial area (e.g. atypical facial pain, trigeminal neuralgia, zoster neuralgia). A series of opioid blockades immediately led to a clinical significant reduction of pain intensity in our patient and made a reduction of analgesic drugs possible. There were no more pain attacks. In a few cases of SUNCT long-lasting remissions were observed (5, 11). However, the immediate pain reduction after performing the blockade, the long duration of good pain control in our case (> 16 months) and the immediate recurrence of pain attacks after further dose-reduction of drugs made it most unlikely that the postulated effect had been a long-lasting remission only.
We hope that the positive effect of GLOA observed in our patient can be confirmed in other patients.