Trigeminal microvascular decompression for short-lasting unilateral neuralgiform headache attacks

Abstract

A significant proportion of patients with short-lasting unilateral neuralgiform headache attacks (SUNHA) are refractory to medical treatments. Neuroimaging studies have suggested a role for ipsilateral trigeminal neurovascular conflict with morphological changes in the pathophysiology of this disorder. We present the outcome of an uncontrolled open-label prospective single centre study conducted between 2012 and 2020, to evaluate the efficacy and safety of trigeminal microvascular decompression in refractory chronic SUNHA with magnetic resonance imaging evidence of trigeminal neurovascular conflict ipsilateral to the pain side. Primary endpoint was the proportion of patients who achieved an “excellent response”, defined as 90-100% weekly reduction in attack frequency, or “good response”, defined as a reduction in weekly headache attack frequency between 75% and 89% at final follow-up, compared to baseline. These patients were defined as responders. The study group consisted of 47 patients of whom 31 had SUNCT and 16 had SUNA (25 females, mean age ± SD 55.2 years ± 14.8). Participants failed to respond or tolerate a mean of 8.1 (±2.7) preventive treatments pre-surgery. Magnetic resonance imaging of the trigeminal nerves (n = 47 patients, n = 50 symptomatic trigeminal nerves) demonstrated ipsilateral neurovascular conflict with morphological changes in 39/50 (78.0%) symptomatic nerves and without morphological changes in 11/50 (22.0%) symptomatic nerves. Post-operatively, 37/47 (78.7%) patients obtained either an excellent or a good response. Ten patients (21.3%, SUNCT = 7 and SUNA = 3) reported no post-operative improvement. The mean post-surgery follow-up was 57.4 ± 24.3 months (range 11-96 months). At final follow-up, 31 patients (66.0%) were excellent/good responders. Six patients experienced a recurrence of headache symptoms. There was no statistically significant difference between SUNCT and SUNA in the response to surgery (p = 0.463). Responders at the last follow-up were however more likely not to have interictal pain (77.42% vs 22.58%, p = 0.021) and to show morphological changes on the magnetic resonance imaging (78.38% vs 21.62%, p = 0.001). The latter outcome was confirmed in the Kaplan Meyer analysis, where patients with no morphological changes were more likely to relapse overtime compared to those with morphological changes (p = 0.0001). All but one patient who obtained an excellent response without relapse, discontinued their preventive medications. Twenty-two post-surgery adverse events occurred in 18 patients (46.8%) but no mortality or severe neurological deficit was seen. Trigeminal microvascular decompression may be a safe and effective long-term treatment for short-lasting unilateral neuralgiform headache attacks patients with magnetic resonance evidence of neurovascular conflict with morphological changes.

Short-lasting unilateral neuralgiform headache attacks (SUNCT/SUNA): a narrative review of interventional therapies

“…All patients had exhausted other treatments with a median of 7 preventive medications trialled prior to MVD. Partially skewed by the scale of the Lambru et al 30 study, MVD had the longest postoperative surveillance interval with a mean follow-up of 42.4 months.…”

“…Notably, Lambru et al 30 recently published their results from a large prospective study where they evaluated the role of MVD in 47 SUNCT/SUNA patients with MRI evidence of ipsilateral neurovascular conflict. Participants had failed to benefit from a mean of 8 preventive medications.…”

“…MVD is unique among the interventions reviewed since it is the most dependent on variability in neurovascular compression and surgical technique. Lambru et al 30 expand on the relationship between SUNCT/SUNA and neurovascular compression by demonstrating that the patients with increased evidence of trigeminal morphological changes were more likely to experience better outcomes after undergoing MVD. With that said, an understudied component of MVD is the potential benefit of internal neurolysis in patients without evidence of a compressive vessel or those with refractory/recurrent pain following MVD.…”

Similarities and differences between SUNCT and SUNA: a cross-sectional, multicentre study of 76 patients in China

“…Earlier studies have explored the characteristics of, and relationship between, SUNCT and SUNA [5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Some specialists have suggested that the classifications should be revised.…”

Recent Advances and Updates in Trigeminal Autonomic Cephalalgias

“…Trigeminal neurovascular conflict in short-lasting unilateral neuralgiform headache attacks has been seen in the past with conflicting results when these neurovascular conflicts were treated 32,33 ; however, a recent study explored the long-term efficacy of microvascular decompression of the trigeminal nerve in patients described as having medication-refractory SUNHA, and 78.7% of the 47 patients had a good or excellent response. 34 Whether the outcome is more a reflection of some misdiagnosis of trigeminal neuralgia as SUNHA in the first instance, combined with SUNHA with nerve irritation, is an open question. It is likely that just as SUNHA has pain triggerable from cutaneous stimulation that trigeminal nerve irritation would produce the same clinical picture.…”