Headaches of otolaryngological interest: current status while awaiting revision of classification. Practical considerations and expectations.

In 1988, diagnostic criteria for headaches were drawn up by the International Headache Society (IHS) and is divided into headaches, cranial neuralgias and facial pain. The 2(nd) edition of the International Classification of Headache Disorders (ICHD) was produced in 2004, and still provides a dynamic and useful instrument for clinical practice. We have examined the current IHC, which comprises 14 groups. The first four cover primary headaches, with "benign paroxysmal vertigo of childhood" being the forms of migraine of interest to otolaryngologists; groups 5 to 12 classify "secondary headaches"; group 11 is formed of "headache or facial pain attributed to disorder of cranium, neck, eyes, ears, nose, sinuses, teeth, mouth or other facial or cranial structures"; group 13, consisting of "cranial neuralgias and central causes of facial pain" is also of relevance to otolaryngology. Neither the current classification system nor the original one has a satisfactory collocation for migraineassociated vertigo. Another critical point of the classification concerns cranio-facial pain syndromes such as Sluder's neuralgia, previously included in the 1988 classification among cluster headaches, and now included in the section on "cranial neuralgias and central causes of facial pain", even though Sluder's neuralgia has not been adequately validated. As we have highlighted in our studies, there are considerable similarities between Sluder's syndrome and cluster headaches. The main features distinguishing the two are the trend to cluster over time, found only in cluster headaches, and the distribution of pain, with greater nasal manifestations in the case of Sluder's syndrome. We believe that it is better and clearer, particularly on the basis of our clinical experience and published studies, to include this nosological entity, which is clearly distinct from an otolaryngological point of view, as a variant of cluster headache. We agree with experts in the field of headaches, such as Olesen and Nappi who contributed to previous classifications, on the need for a revised classification, particularly with regards to secondary headaches. According to the current Committee on headaches, the updated version of the classification, presently under study, is due to be published soon; it is our hope that this revised version will take into account some of the above considerations.