[Neurological or interdisciplinary outpatient pain treatment: comparison of treatment success and satisfaction]. / Neurologische oder interdisziplinäre Schmerzambulanz: Vergleich des Behandlungserfolges und der Zufriedenheit.

The aim of this study was to compare the satisfaction and success of treatment for pain patients who were interdisciplinary (anaesthesiological, psychosomatic, neurological, orthopedic) treated or underwent neurological care alone. Methods We selected 183 patients who were treated in our neurological clinic and in our interdisciplinary pain management center (IST). Of these, 142 patients having polyneuropathy, headache or muskuloskelettal pain were included in the final analysis. 39 patients (27.5 %) were treated in the IST and 103 patients were treated exclusively by a neurologist. These patients were asked to complete a questionnaire, and were queried about the satisfaction and pain parameters. Results The neurological and multidisciplinary pain treatment led to a similar improvement in pain (p < 0.001). This effect was independent of the underlying disease. The interdisciplinary outpatient treatment resulted not primarily in an increased patient satisfaction. Conclusions The reduction of pain and patient satisfaction of neurological outpatient pain treatment were comparable with those of a multidisciplinary outpatient therapy. The only significant advantage of the interdisciplinary treatment was lower hospitalization rate after therapy. This result cannot evaluate the efficiency of inpatient or day hospital pain management, but suggests that in many cases a neurological outpatient pain therapy is sufficient, so that neurological outpatient care should be promoted.

Active pain coping is associated with the response in real-time fMRI neurofeedback during pain.

Real-time functional magnetic resonance imaging (rt-fMRI) neurofeedback is used as a tool to gain voluntary control of activity in various brain regions. Little emphasis has been put on the influence of cognitive and personality traits on neurofeedback efficacy and baseline activity. Here, we assessed the effect of individual pain coping on rt-fMRI neurofeedback during heat-induced pain. Twenty-eight healthy subjects completed the Coping Strategies Questionnaire (CSQ) prior to scanning. The first part of the fMRI experiment identified target regions using painful heat stimulation. Then, subjects were asked to down-regulate the pain target brain region during four neurofeedback runs with painful heat stimulation. Functional MRI analysis included correlation analysis between fMRI activation and pain ratings as well as CSQ ratings. At the behavioral level, the active pain coping (first principal component of CSQ) was correlated with pain ratings during neurofeedback. Concerning neuroimaging, pain sensitive regions were negatively correlated with pain coping. During neurofeedback, the pain coping was positively correlated with activation in the anterior cingulate cortex, prefrontal cortex, hippocampus and visual cortex. Thermode temperature was negatively correlated with anterior insula and dorsolateral prefrontal cortex activation. In conclusion, self-reported pain coping mechanisms and pain sensitivity are a source of variance during rt-fMRI neurofeedback possibly explaining variations in regulation success. In particular, active coping seems to be associated with successful pain regulation.

Meta-analysis of real-time fMRI neurofeedback studies using individual participant data: How is brain regulation mediated?

An increasing number of studies using real-time fMRI neurofeedback have demonstrated that successful regulation of neural activity is possible in various brain regions. Since these studies focused on the regulated region(s), little is known about the target-independent mechanisms associated with neurofeedback-guided control of brain activation, i.e. the regulating network. While the specificity of the activation during self-regulation is an important factor, no study has effectively determined the network involved in self-regulation in general. In an effort to detect regions that are responsible for the act of brain regulation, we performed a post-hoc analysis of data involving different target regions based on studies from different research groups. We included twelve suitable studies that examined nine different target regions amounting to a total of 175 subjects and 899 neurofeedback runs. Data analysis included a standard first- (single subject, extracting main paradigm) and second-level (single subject, all runs) general linear model (GLM) analysis of all participants taking into account the individual timing. Subsequently, at the third level, a random effects model GLM included all subjects of all studies, resulting in an overall mixed effects model. Since four of the twelve studies had a reduced field of view (FoV), we repeated the same analysis in a subsample of eight studies that had a well-overlapping FoV to obtain a more global picture of self-regulation. The GLM analysis revealed that the anterior insula as well as the basal ganglia, notably the striatum, were consistently active during the regulation of brain activation across the studies. The anterior insula has been implicated in interoceptive awareness of the body and cognitive control. Basal ganglia are involved in procedural learning, visuomotor integration and other higher cognitive processes including motivation. The larger FoV analysis yielded additional activations in the anterior cingulate cortex, the dorsolateral and ventrolateral prefrontal cortex, the temporo-parietal area and the visual association areas including the temporo-occipital junction. In conclusion, we demonstrate that several key regions, such as the anterior insula and the basal ganglia, are consistently activated during self-regulation in real-time fMRI neurofeedback independent of the targeted region-of-interest. Our results imply that if the real-time fMRI neurofeedback studies target regions of this regulation network, such as the anterior insula, care should be given whether activation changes are related to successful regulation, or related to the regulation process per se. Furthermore, future research is needed to determine how activation within this regulation network is related to neurofeedback success.

The efficacy of acupuncture in human pain models: a randomized, controlled, double-blinded study.

Acupuncture is frequently used to treat pain, although data supporting the analgesic efficacy from placebo-controlled studies is sparse. In order to get evidence for acupuncture analgesia we performed a study with 2 well-recognized experimental human pain models - the cold-pressor (CP) test and intradermal capsaicin injection. Fifty healthy men were included. Our study compared Traditional Chinese Medicine-based acupuncture to sham acupuncture with Streitberger placebo needles in a randomized, controlled, double-blinded trial. The primary endpoint was the reduction of mean pain intensity during 3minutes of CP test or of mean pain intensity within 10minutes after capsaicin injection. Secondary parameters were defined to substantiate the findings. To ensure comparability, somatosensory (measured by quantitative sensory testing) and psychological parameters were investigated and found to be the same in both groups. Analyses (repeated-measures analyses of variance) showed a significant (P=0.009) but clinically questionable pain reduction in the verum group for capsaicin-induced pain, which was mainly driven by an effect of Traditional Chinese Medicine acupuncture on small pain ratings (max. reduction from 7/100 rating at baseline to 2.5/100 at intervention). Neither pin-prick hyperalgesia, nor allodynia, nor neurogenic flare associated with capsaicin injection, nor pain ratings during the CP test, were significantly different between groups. In addition, there was no placebo response. Attitude towards acupuncture and partial unblinding did not affect the results. We conclude that acupuncture on predefined points has a minor effect on experimental pain in healthy subjects.