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: 6.75). 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.

3 Followers
 · 
131 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Concussion after a force to the head is called mild traumatic brain injury (mTBI). Approximately 1 in 5 patients with mTBI will develop chronic pain (headache and widespread pain, possibly of central origin) and/or sleep problems (insomnia, disordered breathing, periodic limb movements). However, the predisposing mechanisms for chronic pain in patients with mTBI are unknown. Mild traumatic brain injury is a rare model to prospectively assess the risk factors and mechanisms for pain chronification from the injury onset in the absence of pretrauma comorbidity or medication. In the acute phase, headaches and sleep disturbances seem to predict the poorest long-term cognitive and mood outcomes. Although recent studies suggest that certain brain biomarkers and mood alterations (eg, anxiety, depression) contribute, the causality of chronic pain remains unclear. In mTBI patients with pain, poor sleep quality was correlated with fast beta and gamma electroencephalographic activity in frontal, central, and occipital electroencephalographic (EEG) derivations in all sleep stages. Sleep recuperative function seems to be disturbed by persistent wake EEG activity, corroborating patient complaints such as feeling awake when asleep. Pain and sleep management in mTBI is not yet evidence-based. Treatments include cognitive behavioral and light therapies, medications, and continuous positive airway pressure (CPAP) or oral appliances for disordered sleep breathing. Customized approaches are indicated for mTBI, pain, and sleep complaints. Further studies in pediatric, sport, and transportation populations are needed to prevent TBI chronification. Improvements are emerging in biomarker sensitivity and specificity and management strategies for TBI, pain, and sleep comorbidities.
    Pain 04/2015; 156 Suppl 1:S75-85. DOI:10.1097/j.pain.0000000000000111 · 5.84 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: People around the world suffer chronic lower back pain. Because spine imaging often does not explain the degree of perceived pain reported by patients, the role of the processing of nociceptor signals in the brain as the basis of pain perception is gaining increased attention. Modern neuroimaging techniques (including functional and morphometric methods) have produced results that suggest which brain areas may play a crucial role in the perception of acute and chronic pain. In this study, we examined 12 patients with chronic low back pain and sciatica, both resulting from lumbar disc herniation. Structural magnetic resonance imaging (MRI) of the brain was performed 1 day prior to and about 4 weeks after microsurgical lumbar discectomy. The subsequent MRI revealed an increase in gray matter volume in the basal ganglia but a decrease in volume in the hippocampus, which suggests the complexity of the network that involves movement, pain processing, and aspects of memory. Interestingly, volume changes in the hippocampus were significantly correlated to preoperative pain intensity but not to the duration of chronic pain. Mapping structural changes of the brain that result from lumbar disc herniation has the potential to enhance our understanding of the neuropathology of chronic low back pain and sciatica and therefore may help to optimize the decisions we make about conservative and surgical treatments in the future. The possibility of illuminating more of the details of central pain processing in lumbar disc herniation, as well as the accompanying personal and economic impact of pain relief worldwide, calls for future large-scale clinical studies.
    Frontiers in Human Neuroscience 02/2015; 9. DOI:10.3389/fnhum.2015.00012 · 2.90 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Chronic fatigue syndrome (CFS) is a debilitating and complex disorder characterized by profound fatigue with uncertain pathologic mechanism. Neuroimage may be an important key to unveil the central nervous system (CNS) mechanism in CFS. Although most of the studies found gray matter (GM) volumes reduced in some brain regions in CFS, there are many factors that could affect GM volumes in CFS, including chronic pain, stress, psychiatric disorder, physical activity, and insomnia, which may bias the results. In this paper, through reviewing recent literatures, we discussed these interferential factors, which overlap with the symptoms of CFS.
    Evidence-based Complementary and Alternative Medicine 01/2015; 2015:1-7. DOI:10.1155/2015/380615 · 2.18 Impact Factor