Imaging pain in patients: is it meaningful?
OBJECTIVE
Neuroimaging methods are widely used by researchers and clinicians interested in better understanding the functioning of the human brain in health and disease. Advances have been made in understanding how nociceptive processing within the healthy human central nervous system generates a conscious perception of pain. The focus has now shifted towards patient-related research, harnessing earlier developments to test specific hypotheses in a broad range of chronic pain disorders. The timing is ideal to assess the utility of data generated from these studies.


RESULTS
This review discusses how clinical pain is represented in the human brain as compared with the processing of acute pain in healthy controls. The imaging literature is reviewed for hypotheses that have been tested in patients regarding mechanisms that might contribute towards the development of chronic pain. Issues related to plasticity, central sensitization, psychological confounds, genetics, and necrosis are examined.


CONCLUSIONS
Results to date strongly support the notion that neuroimaging will aid our understanding of basic mechanisms contributing to the generation of chronic pain states. These techniques might help diagnose a patient's pain condition in a more objective and robust way, enabling better targeting of therapies and rapid development of compounds to alleviate pain.
Schweinhardt
Petra
P
Department of Physiology, Anatomy and Genetics, Oxford University, Oxford, Oxford, UK.
Lee
Michael
M
Tracey
Irene
I
D002490:Central Nervous System / Q000473:pathology; D002908:Chronic Disease; D003952:Diagnostic Imaging; D006801:Humans; D010146:Pain / Q000473:pathology*