Article

Chronic back pain is associated with decreased prefrontal and thalamic gray matter density

Department of Physiology and Institute of Neuroscience, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611, USA.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.34). 12/2004; 24(46):10410-5. DOI: 10.1523/JNEUROSCI.2541-04.2004
Source: PubMed

ABSTRACT

The role of the brain in chronic pain conditions remains speculative. We compared brain morphology of 26 chronic back pain (CBP) patients to matched control subjects, using magnetic resonance imaging brain scan data and automated analysis techniques. CBP patients were divided into neuropathic, exhibiting pain because of sciatic nerve damage, and non-neuropathic groups. Pain-related characteristics were correlated to morphometric measures. Neocortical gray matter volume was compared after skull normalization. Patients with CBP showed 5-11% less neocortical gray matter volume than control subjects. The magnitude of this decrease is equivalent to the gray matter volume lost in 10-20 years of normal aging. The decreased volume was related to pain duration, indicating a 1.3 cm3 loss of gray matter for every year of chronic pain. Regional gray matter density in 17 CBP patients was compared with matched controls using voxel-based morphometry and nonparametric statistics. Gray matter density was reduced in bilateral dorsolateral prefrontal cortex and right thalamus and was strongly related to pain characteristics in a pattern distinct for neuropathic and non-neuropathic CBP. Our results imply that CBP is accompanied by brain atrophy and suggest that the pathophysiology of chronic pain includes thalamocortical processes.

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    • "However, the risk of chronic pain increases to nearly 50% with thoracotomies and amputations (Kehlet et al., 2006). As pain progresses from an acute origin, as from an injury or surgery, to a chronic condition, negative emotional states associated with chronic pain not only exacerbate physiological pain sensitivity (Borsook et al., 2013) but may also increase the incidence of comorbidities like depression, anxiety, anhedonia (e.g., the inability to experience pleasure), sleep disturbance, decision-making abnormalities, and even risk for suicide (Apkarian et al., 2004). In spite of its prevalence and impact on patients' lives and on society, chronic pain and comorbid affective disorders are still poorly managed and current therapies are often inadequate (Backonja et al., 2006, Finnerup et al., 2010). "
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    Full-text · Article · Jan 2016 · The Journal of Comparative Neurology
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    • "Prefrontal cortices, as DLPFC, processes attentional and memory components of noxious stimulation (Peyron et al., 2000). However, in other chronic pains the DLPFC showed an increase of GMC (Apkarian et al., 2004). BMS is often associated with depression and the DLPFC is likely a key area in depression, together with hippocampus and neighbouring areas. "
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    • "In the brain, preliminary evidence of pain-related structural changes was initially revealed by functional magnetic resonance imaging (fMRI) mostly concentrated on human adult brain. Imaging studies showing altered brain morphology and connectivity in multiple types of chronic pain conditions, such as chronic back pain[18]fibromyalgia[19]complex regional pain syndrome[20]and headache[21], have been reported. However, as most of these studies were conducted based on images with limited spatial resolution and temporal resolution, changes in local neural circuits of individual neurons and synapses in the brain are not clearly demonstrated. "
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