Enlarging the spectrum of cluster headache: Extracranial autonomic involvement revealed by voice analysis

People with cluster headache (CH) are frequently burdened by misdiag-nosis or diagnostic delay. The peculiar somatic and behavioral changes characterizing patients with CH are not useful to improve diagnostic accuracy. In our clinical experi-ence, we noticed a typical voice quality with low and croaking tone in patients with CH.In this cross-sectional study, we evaluated, by digital voice analysis, whether it is pos-sible to identify typical voice quality characterizing patients with CH compared with healthy controls (HCs). Furthermore, to investigate whether putative differences in voice characteristics could be underpinned by constitutional aspects or pathological processes of vocal cords, subjects underwent a videolaryngostroboscopy. Smoking habits and alcohol consumption were specifically investigated. Conclusion: Creaky phonation is a “physiological mode of laryngeal operation” usually underpinned by shortened and thickened vocal folds. Creaky voice phonation can be due to a vocal fold's reduced capability to become slack or flaccid secondary to vocal cord edema underpinned by laryngopharyngeal reflux affecting the phonatory mecha-nisms in patients with CH. The laryngopharyngeal reflux may represent a dysautonomic sign related to the increased parasympathetic tone during in- bout period, reinforcing the hypothesis of an extracranial autonomic dysfunction as part of CH clinical picture.