Overview on tools and methods to assess neuropathic trigeminal pain.

This article provides a brief overview of the tools and methods that may be useful to assess neuropathic trigeminal pain. Pain is a complex multidimensional and biopsychosocial experience. While the assessment of neuropathic trigeminal pain is complex, there are several meaningful ways available for the systematic assessment of neuropathic pain and its effects and manifestations. The key to such an analysis is a standardized pain history and examination and a good knowledge of pain mechanisms. Patients can be asked to provide detailed information about their spontaneous pain (ie, stimulus-independent pain), eg, quality, intensity, localization, time course, and modifying factors. Stimulus-dependent pain components can be characterized with clinical examination procedures and quantitative psychophysical techniques such as application of mechanical, thermal, chemical, and electrical stimuli. The description of the stimulus-dependent pain is important to reveal the function of the somatosensory system and to map the extent of hyperalgesia, hyperesthesia and allodynia, because the normal relationship between stimulus intensity and perceived intensity is distorted in many neuropathic pain conditions. In addition to the psychophysical techniques, a number of laboratory tests for assessment of trigeminal pain have been developed and tested, although critical information on sensitivity, specificity, and predictive values is still scarce. There is also a need for common guidelines on classification, diagnostic procedures, and management. This will require concerted international, interdisciplinary action.