SUNCT and SUNA: An Update.

BACKGROUND: Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache with autonomic symptoms (SUNA) are rare and disabling primary headache disorders that are subtypes of Short-lasting unilateral neuralgiform headache attacks (SUNHA). AIM: The aim of this narrative review was to provide a comprehensive update on headache phenotype, pathophysiology, and various treatment options available for SUNCT and SUNA. METHODS: References for this review were identified by searches of articles published in the English language in PubMed between 1978 and October 2020 using "short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT)", "short-lasting unilateral neuralgiform headache with autonomic symptoms (SUNA)", "short-lasting unilateral neuralgiform headache attacks (SUNHA)", "trigeminal autonomic cephalalgias" as keywords in various combinations. RESULTS: Of a potential 1103 articles, seven case series describing clinical characteristics of SUNCT/SUNA patients were identified for this review. For symptomatic/secondary SUNCT/SUNA, 53 individual case reports, and one case series were reviewed. One placebo-controlled trial and 11 open-label case series that evaluated various medical and surgical treatments in SUNCT/SUNA were also reviewed. Available literature suggests that SUNCT and SUNA are subtypes of the same disorder characterized by severe side locked short duration headache with ipsilateral prominent cranial autonomic symptoms and signs. Pathophysiology may involve both peripheral and central mechanisms. Lamotrigine is the most effective preventive therapy while intravenous lidocaine is the most efficacious drug as transitional therapy for severe disabling attacks. Surgical options including microvascular decompression in those having neurovascular conflict, occipital nerve stimulation, and hypothalamic deep brain stimulation can be alternative treatment options for medically refractory patients.

The neurosurgical treatment of craniofacial pain syndromes: current surgical indications and techniques.

Craniofacial pain syndromes are comprised of multiple pathological entities resulting in pain referred to the scalp, face, or deeper cranial structures. In a small subset of patients affected by those syndromes, pharmacological and physical therapies fail in alleviating pain. In some of those refractory patients surgical procedures aimed at relieving pain are indicated and have been adopted with variable results and safety profiles. In this review, the authors describe craniofacial pain syndromes that most commonly fail to respond to pharmacological therapies and may be amenable to tailored surgical procedures. In particular, trigeminal, glossopharyngeal, and occipital neuralgias are considered, as well as some primary headache syndromes such as cluster headache, short unilateral neuralgiform headache with conjunctival injection and tearing/short unilateral neuralgiform headache with autonomic symptoms, and migraine. Surgical techniques, including the implantation of deep brain or peripheral nerve electrodes with subsequent chronic stimulation, microvascular decompression of neurovascular conflicts, and percutaneous lesioning of neural structures are described. Finally, surgical indications, outcomes, and safety of these procedures are presented.

SUNCT/SUNA and neurovascular compression: new cases and critical literature review.

BACKGROUND: Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache with cranial autonomic symptoms (SUNA) are primary headache syndromes. A growing body of literature has focused on brain magnetic resonance imaging (MRI) evidence of neurovascular compression in these syndromes. OBJECTIVE: The objective of this article is to assess whether SUNCT is a subset of SUNA or whether the two are separate syndromes and clarify the role of neurovascular compression. METHOD: We describe three new SUNCT cases with MRI findings of neurovascular compression and critically review published SUNCT/SUNA cases. RESULTS: We identified 222 published SUNCT/SUNA cases. Our three patients with neurovascular compression added to the 34 cases previously described (16.9%). SUNCT and SUNA share the same clinical features and therapeutic options. At present, there is no available abortive treatment for attacks. Lamotrigine was effective in 64% of patients; topiramate and gabapentin in about one-third of cases. Of the 34 cases with neurovascular compression, seven responded to drug therapies, 16 patients underwent microvascular decompression of the trigeminal nerve (MVD) with effectiveness in 75%. CONCLUSIONS: We suggest that SUNCT and SUNA should be considered clinical phenotypes of the same syndrome. Brain MRI should always be performed with a dedicated view to exclude neurovascular compression. The high percentage of remission after MVD supports the pathogenetic role of neurovascular compression.

SUNCT and SUNA: medical and surgical treatments.

Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) are rare and often disabling primary headache disorders. Their management can be challenging. The abortive therapies are not generally useful as the attacks are relatively short lasting. A myriad of pharmacological preventive treatments have been tried in single case reports or small series in an open-label fashion. Lamotrigine, as an oral preventive treatment, and lidocaine, as an intravenous transitional treatment, seem to be the most effective therapies. For medically intractable chronic forms of SUNCT and SUNA, several surgical approaches have been tried. These include ablative procedures involving the trigeminal nerve or the Gasserian ganglion, microvascular decompression of the trigeminal nerve, and neurostimulation techniques. This review provides an overview of the current pharmacological and surgical options for SUNCT and SUNA syndromes.

Microvascular decompression of the trigeminal nerve in the treatment of SUNCT and SUNA.

BACKGROUND: Medical management of short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) syndrome and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) is often unsatisfactory. METHODS: The authors report nine cases of SUNCT/SUNA that failed medical treatment and had an aberrant arterial loop either in contact with or compressing the appropriate trigeminal nerve demonstrated on MRI. All underwent microvascular decompression of the ipsilateral trigeminal nerve for intractable pain. RESULTS: Immediate and complete relief of SUNCT and SUNA symptoms occurred in 6/9 (67%) cases. This was sustained for a follow-up period of 9-32 months (mean 22.2). In 3/9 (33%) cases, there was no benefit. Ipsilateral hearing loss was observed in one case. CONCLUSION: Medically intractable SUNCT and SUNA subjects with a demonstrable aberrant arterial loop impinging on the trigeminal nerve on neuroimaging may benefit from microvascular decompression.

Cluster headache and TACs: rationale for central and peripheral neuromodulation.

Cluster headache, the most severe of primary headache conditions for functional and social impairment it provokes, has been recently the object of a great amount of clinical, physiopathological, surgical and functional neuroradiological studies aimed to uncover the real mechanisms which underlie its disabling manifestations. Refinement of methodological and systematic features of multidisciplinary researches in this field has been allowing for more and more precise delineations of the role of both peripheral and central nervous system's contribution in pathophysiology of the disease. Aim of this manuscript is the report of the present knowledge in the role of the different surgical options in the treatment of drug-resistant cluster headache and Short-lasting Unilateral neuralgiform headache attacks with Conjunctival injection and Tearing (SUNCT), which take into account their different hypothesized pathological mechanisms and which comprise central nervous system's approach (Deep Brain Stimulation [DBS] and peripheral approach, namely Occipital Nerve Stimulation (ONS) and Vagal Nerve Stimulation (VNS).

Trigeminal autonomic cephalalgias.

The trigeminal autonomic cephalalgias (TACs) are a group of primary headache syndromes all marked by headache and associated autonomic features. The TACs include cluster headache, paroxysmal hemicrania, hemicrania continua, and short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing syndrome. Diagnosis is made after looking at headache frequency, duration, and accompanying symptoms. Each TAC has its own unique treatment modality, which is discussed in depth.

Percutaneous balloon compression for trigeminal neuralgias and autonomic cephalalgia.

OBJECTIVE: This prospective study aimed to evaluate the results of percutaneous trigeminal ganglion balloon compression (BC) in patients with various types of trigeminal neuralgia (TN) and autonomic cephalalgia. METHODS: Twenty-five consecutive patients underwent BC and were followed up for 27-60 months. They were divided into 2 groups: group A (n=18) patients with idiopathic TN and group B (n=7) patients with secondary TN (n=5) and trigeminal autonomic cephalalgia (TAC) (n=2). RESULTS: Postoperatively, 15 patients in group A experienced pain relief, one required medication and 2 had no response; in group B, 6 were free of pain, including the 2 patients with TAC, and one required medication. Complications in both groups were either functionally trivial or infrequent. None of the patients developed keratitis or anesthesia dolorosa. Pain recurrence occurred early (<6 months) in one patient from group B, and late in 2 patients from group A. CONCLUSION: Balloon compression is a minimally invasive procedure that seems to be comparably successful for idiopathic and secondary TN, as well as TAC. However, further studies are deemed necessary to establish it as the first-line treatment in medically resistant trigeminal pain.

Update on neurosurgical treatment of chronic trigeminal autonomic cephalalgias and atypical facial pain with deep brain stimulation of posterior hypothalamus: results and comments.

The objective of this study is to describe the therapeutic effect and the technical and surgical problems of deep brain stimulation (DBS) of the posterior hypothalamus over seven years, for treatment of chronic trigeminal autonomic cephalalgias and atypical facial pain. We report a surgical series of 20 patients that underwent DBS of the posterior hypothalamus. This series includes 16 patients with chronic cluster headache (CH), one patient with short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and three patients with atypical facial pain. All patients of this series were resistant to any pharmacological and conservative treatment. The stimulated target was the same in the whole series even though stereotactic coordinates of the target referred to the midcommissural point differ slight in the Y anteroposterior value due to individual anatomical variability. The commissures based reference system was adapted to individual anatomical landmarks of the brainstem adding to the registration a third reference point below the commissural plane. The stimulation parameters of unipolar stimulation were similar in the whole series: 180 Hz, 60 mus, 1-3 V. In the CH series, at five years follow-up the percentage of total number of days free from pain attacks improved from 1%-2% to 71%. Ten patients of this series had a complete and persistent pain-free state at 18 months follow-up and the patient with SUNCT has complete pain relief. In the three patients with atypical facial pain, the neurostimulation procedure was absolutely unsuccessful. DBS of the posterior hypothalamus produced a significant and marked reduction of pain bouts in CH patients and in the SUNCT patient. The attempts to treat atypical facial pain in three patients failed.

Deep brain stimulation in craniofacial pain: seven years' experience.

Cluster headache (CH) is a primary headache with excruciatingly painful attacks that are strictly unilateral. About 10% of cases experience no significant remission, and about 15% of these do not respond to medication, so surgery is considered. Neuroimaging studies show that the posterior inferior hypothalamus is activated during CH attacks and is plausibly the CH generator. We report on 16 chronic CH patients, with headaches refractory to all medication, who received long-term hypothalamic stimulation following electrode implant to the posterior inferior hypothalamus. After a mean follow-up of 23 months, a persistent pain-free to almost pain-free state was achieved in 13/16 patients (15/18 implants; 83.3%) a mean of 42 days (range 1-86 days) after monopolar stimulation initiation. Ten patients (11 implants) are completely pain-free. A common side effect was transient diplopia, which limited stimulation amplitude. In one patient, a small non-symptomatic haemorrhage into the 3rd ventricle occurred following implant, but regressed 24 h later. Persistent side effects are absent except in one patient with bilateral stimulation, in whom stimulation was stopped to resolve vertigo and worsened bradycardia, but was resumed later without further problems. Hypothalamic stimulation is an effective, safe and well tolerated treatment for chronic drug-refractory CH. It appears as a valid alternative to destructive surgical modalities, and has the additional advantage of being reversible.