Primary headaches and trigeminal neuralgia: neuropathic pain yes or not? Evidences from neurophysiological procedures

Abstract

Despite the fact that neurophysiological evaluation is not useful for primary headache diagnosis, the nociceptive system exploration through reflexes and evoked potentials procedures may give an aid in understanding the pathophysiological mechanism subtending pain. Neuropathic pain is caused by a lesion or disease of the somatosensory nervous system, which is supported by clinical evaluation and instrumental assessment by trigeminal and nociceptive reflexes and laser evoked potentials. The same methods, applied to migraine and cluster headache, together with evidences coming from structural and functional neuroimaging, excluded the neuropathic origin of pain, which is attaining to symptomatic and idiopathic trigeminal neuralgia, but confirmed a complex dysfunction of pain processing. Tension-type headache fits with a model of non-nociceptive and non-neuropathic pain, subtended by a complex interaction of peripheral muscular and central neuronal factors. The presence of altered modulation of pain concurs with migraine and tension-type headache, and should be taken into account for the choice of the best therapeutic approach.

Trigeminal neuralgia and associated unwarranted dental treatment

“…The basic neurophysiologic mechanisms of TN are not yet entirely understood even then the most accepted theory of TN aetiology is compression on the intracranial vasculature by trigeminal nerve originating from pons 14 . Magnetic imaging resonance (MRI) of posterior cranial fossa during surgery for TN has shown close approximation of trigeminal nerve trunk with adjoining blood vessel, supporting the hypothesis of nerve compression 15 .…”

Cluster Headache: Deep Brain Stimulation

“…The underlying pathophysiology in cluster headache (CH) is not fully understood [10][11][12][13][14][15][16][17]. Attacks often involve a nociceptive (facial pain in the trigeminal nerve's ophthalmic distribution) and a parasympathetic component (tearing, redness, nasal discharge, etc.…”

Ventral tegmental area deep brain stimulation for chronic cluster headache: Effects on cognition, mood, pain report behaviour and quality of life

“…Patients with CH show greater anxiety, depression and worse quality of life compared with healthy populations (2). The exact pathophysiology in cluster headache (CH) is a matter of debate (3–10). The seasonality and periodicity of CH attacks are indicative of a possible hypothalamic role (7,11).…”