Abstract
Dear Sir For an Ear, Nose and Throat (ENT) specialist with an interest in headaches it is imperative to make use of an existing classification system for headache, because multidisciplinary use of the same classification will lead to benefits in diagnostics, mutual interdisciplinary communication, scientific communication and, possibly, future therapy for patients suffering from pain. Therefore, I attempt to classify patients according to the International Classification of Headache Disorders, 2nd edn (ICHD-II). This regularly leads to some ‘problems’ that I describe below.
In Chapter 11, there is mention of headaches attributed to disorders of the ear. Most of my patients with earache, however, do not suffer from a headache. Is it appropriate for me to classify them as 11.4? Hardly! Yet there is no separate heading for earaches. The answer could be that a ‘simple’ earache without headache does not belong in a headache classification, but it seems that the authors did indeed set out to classify all pain in the head and neck area. This because Cranial Neuralgias are mentioned separately without the additional requirement for headache, and because idiopathic facial pain and burning mouth syndrome are also described without any mention of headache.
This raises the question whether we are actually discussing the same patient population. However, do those patients who are now probably classified mainly as 11.4 by neurologists indeed suffer from a headache combined with otalgia? Or is it a matter of a mixed syndrome, for example, otalgia caused by temporomandibular joint disorder combined with tension-type headache? This might be a rather common combination.
Furthermore, discussion is ongoing whether sinusitis (ICHD-II, 11.5) can or cannot lead to pain, and whether ‘sinus headache’ or ‘contact points headache’ exist. In some articles the sinus headache seems to be a migraine variant that does not meet all the criteria (1, 2). The same difficulty has led to subclassifications that do not completely meet all the required criteria. These have subsequently been classified as probable migraine (ICHD-II, 1.6.1) or cluster headache minus one (3).
Long-term effects of surgical therapy for ‘sinus headache’ are not available. Why then do otolaryngologists so often use surgery of sinus cavities for poorly understood complaints of pain? Possibly, it has something to do with the fact that surgery (or the preceding local anaesthetic) results in a short-term positive effect, which leaves patients with a sense of relief during the first weeks following surgery. When patients are not followed over a longer period the surgeon could be left with the impression that surgical therapy is indeed effective. With that, another question arises, that is, whether certain forms of headache can be provoked by peripheral stimulation that can indeed be eliminated through surgery.
Mosser has mentioned that migraines could be provoked by various kinds of peripheral stimulation. Specifically, he mentions the supraorbital, zygomaticotemporal, greater occipital sensory nerve regions, and turbinate/septal pathology (4). More recently Rothrock has stated that if a genetically primed neuron is triggered by a change in the external environment, that neuron may induce a migraine attack (5). This change in the external environment can be peripheral stimulation. I would like to second that with recollections of patients within my own practice who, after medicinal treatment of their allergy, no longer suffered migraines, and of migraine attacks provoked by odours according to some of my patients. This is different from osmophobia as an accompanying symptom.
How about peripheral stimulation for different types of headache? Cluster headaches are thought to be a problem of central origin. Nevertheless, many invasive treatments have been aimed at influencing the peripheral nerves. This may vary from the ganglion pterygopalatinum, the nervus intermedius to, more recently, the occipital nerves (6–8). I have also observed that peripheral nerves may play a part in patients presenting with complaints that could be classified as a cluster headache minus one, who were relieved of their complaints by local blockade of the ganglion pterygopalatinum or local blockade of the occipital nerves with bupivacain and Depo-Medrol®. The question arises whether these are the same groups of patients. It is remarkable that one group of patients with typical symptoms is referred to the neurologist, and that the group with a less clearly described pattern of complaints (Sluder's neuralgia?) finds itself in the hands of an ENT (9).
Elimination of peripheral stimulation in case of tension-type headaches by means of botox also attracts a great deal of interest, even though there is little evidence of its effectiveness.
As I have attempted to describe above, it may be of increasing importance to start sharing expertise regarding pain in the head and neck area. Subclassifications should increasingly be aimed at ‘trigger points’. Designating a particular location as a ‘trigger point’ could then be subject to the patients' reaction to a dose of locally administered anaesthetic, for example, cluster headache provoked by stimulation of the ganglion pterygopalatinum and a type provoked by stimulation of the occipital nerve. This will create improved opportunities for the development of new therapies and provide more insight into why certain therapies are effective for some patients and not for others. Was the local anaesthetic preceding placement of the occipital nerve stimulator successful or not?
Above all, it would be desirable for the above to lead to increased interdisciplinary cooperation in the development of an ICHD-III, with especial reference to Chapter 11, allowing oral surgeons, gnathologists and otolaryngologists to play a more important part. Perhaps it would be wise to change the title to the classification for ‘Headache and Pain in the Head and Neck Area’, also taking into account that neuralgia of the nervus laryngeus superior is found within the classification, even though characterized by pain starting in the throat. Furthermore, I prefer to designate earaches and other mentioned structures in the head and neck area separately without the need for the headache as a criterion.