Pathogenesis, Surgical Treatment, and Cure for SUNCT Syndrome.

BACKGROUND: Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) are characterized by attacks of moderate to severe stabbing pain, strictly unilateral, with periorbital or temporal distribution, associated with cranial autonomic symptoms, such as lacrimation and redness of the ipsilateral eye. METHODS: To obtain mechanistic insights into the pathogenesis of SUNCT syndrome, more than 800 cases treated in our institution during the last 7 years were retrospectively reviewed. Two patients showed typical autonomic symptoms of SUNCT. RESULTS: Magnetic resonance imaging suggested potential compression of the trigeminal nerve by the intracranial artery in these cases and complete remission was achieved by microvascular decompression. CONCLUSIONS: Microvascular decompression provides an appropriate therapeutic choice if vascular compression of the trigeminal nerve is identified. From our 2 cases, we propose that, in some cases of SUNCT diagnosed previously, characteristic symptoms were induced by compression of the side surface of the first branch of the trigeminal nerve at the root exit zone by the intracranial artery.

Short-lasting unilateral neuralgiform headache attacks with ispilateral facial flushing is a new variant of paroxysmal extreme pain disorder.

BACKGROUND: We encountered a 5-year-old girl who had short-lasting, severe, unilateral temporal headaches with ipsilateral lacrimation, nasal congestion and rhinorrhoea, and facial flushing after severe attacks. Family history revealed similar short-lasting, severe headaches in an older brother, younger sister, mother, maternal aunt, and maternal grandfather's brother. METHODS: We performed routine laboratory examinations and electrophysiological and radiological studies for three children, and whole-exome sequencing to determine the genetic causality in this family. RESULTS: Focal hyperperfusion of the right trigeminal root entry zone was seen during a right-sided attack in one child, while left-sided temporal headache attacks were provoked by bilateral electrical stimulation of the upper extremities in another. We identified a novel SCN9A mutation (NM_002977: c.5218G>C, p.Val1740Leu) in all affected family members, but not in any of the unaffected members. SCN9A encodes the voltage-gated sodium-channel type IX alpha subunit known as Na(v)1.7. CONCLUSIONS: Gain-of-function mutations in Na(v)1.7 are well known to cause paroxysmal extreme pain disorder (PEPD), a painful Na-channelopathy characterized by attacks of excruciating deep burning pain in the rectal, ocular, or jaw areas. The SCN9A mutation suggests that our patients had a phenotype of PEPD with a predominant symptom of short-lasting, severe, unilateral headache.

Efficacy of aripiprazole in sulpiride-induced tardive oromandibular dystonia.

Tardive dystonia is a side effect of dopamine receptor-blocking agents, which are mainly used as antipsychotic drugs. The treatment of tardive dystonia is difficult and often unsuccessful. An 82-year-old woman experienced mandibular deviation to the left due to spasm of the masticatory muscles with involuntary chewing movement and Parkinsonism. She had been treated with sulpiride for motility disorder for 5 years. Parkinsonism almost disappeared after the withdrawal of sulpiride, but tardive oromandibular dystonia showed no improvement. Aripiprazole treatment at 3 mg/day improved tardive oromandibular dystonia without worsening Parkinsonism. Low-dosage aripiprazole may be effective for tardive oromandibular dystonia in patients with no other psychiatric disorder.

A case of SUNCT syndrome responsive to zonisamide.

Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) is a rare headache syndrome that represents a subtype of trigeminal autonomic cephalalgia thought to be highly refractory to treatment. More recently, numerous anticonvulsant agents including lamotrigine, topiramate, gabapentin, and carbamazepine have been reported to be partially or completely effective for treating SUNCT. We report the case of a patient with SUNCT in whom symptoms were completely relieved with carbamazepine at 600 mg/day. However, carbamazepine had to be discontinued due to severe rash. Zonisamide was selected for continued treatment, as a Na-channel blocker like carbamazepine but with lower risk of producing skin rashes as caused by carbamazepine. Attacks ceased completely with 300 mg/day of zonisamide achieving a blood serum level of 19 µg/ml. This is the first case report to describe zonisamide alone completely eliminating SUNCT symptoms. Zonisamide should be considered a viable candidate drug for the treatment of SUNCT.

Effectiveness of milnacipran for a patient with pain disorder and long QT syndrome.

The effectiveness of tricyclic antidepressants (TCAs) has been reported for treating pain disorder. However, the use of TCAs is contraindicated for patients with congenital long QT syndrome. We experienced a case of a 38-year-old woman with congenital long QT syndrome and pain disorder in the orofacial region, which was treated successfully with milnacipran. Although nortriptyline was effective for her pain, it could bring about fatal cardiac adverse events. Paroxetine was not effective in this case. Six weeks after the increase to 200 mg/d of milnacipran, her pain had completely disappeared, and her corrected QT interval time was 0.445 milliseconds. Milnacipran may be a safe and effective compound for patients with pain disorder in whom TCAs are contraindicated.

Efficacy of amitriptyline for treatment of somatoform pain disorder in the orofacial region: A case series.

AIMS: To determine the efficacy of amitriptyline and the optimal dosage for treating a somatoform pain disorder in the orofacial region. METHODS: Thirty outpatients with orofacial pain who fulfilled the criteria of pain disorder were recruited for the study. Twenty-three patients had specific precipitating events in their past history, which they considered to be the origin of the pain. Amitriptyline was administered and the dose was gradually increased up to a daily dose of 250 mg. The response to treatment was evaluated using a numeric rating scale and the Clinical Global Impression Scales. RESULTS: Five patients dropped out and 25 patients (83%) completed the trial. Twenty-two patients became pain free or nearly pain free, while 3 patients who also completed the study did not respond at all, even though they took a daily dose of 250 mg amitriptyline. For responders, the mean daily dose of amitriptyline was 77.5 +/- 51.5 mg (range, 10 to 200 mg). Four patients (16%) obtained pain relief with a daily dose of less than 50 mg, while 3 patients (12%) needed a daily dose of 150 mg or more for pain relief. Adverse side effects were observed in 19 patients. CONCLUSION: Amitriptyline was effective in relieving pain associated with a somatoform pain disorder in the orofacial region. The dose of amitriptyline may need to be as high as that used to treat a major depression.