Functional connectivity associated with attention networks differs among subgroups of fibromyalgia patients: an observational case-control study

Fibromyalgia is a heterogenous chronic pain disorder diagnosed by symptom-based criteria. The aim of this study was to clarify different pathophysiological characteristics between subgroups of patients with fibromyalgia. We identified subgroups with distinct pain thresholds: those with a low pressure pain threshold (PL; 16 patients) and those with a normal pressure pain threshold (PN; 15 patients). Both groups experienced severe pain. We performed resting-state functional MRI analysis and detected 11 functional connectivity pairs among all 164 ROIs with distinct difference between the two groups (p < 0.001). The most distinctive one was that the PN group had significantly higher functional connectivity between the secondary somatosensory area and the dorsal attention network (p < 0.0001). Then, we investigated the transmission pathway of pain stimuli. Functional connectivity of the thalamus to the insular cortex was significantly higher in the PL group (p < 0.01 - 0.05). These results suggest that endogenous pain driven by top-down signals via the dorsal attention network may contribute to pain sensation in a subgroup of fibromyalgia patients with a normal pain threshold. Besides, external pain driven by bottom-up signals via the spinothalamic tract may contribute to pain sensations in another group of patients with a low pain threshold. Trial registration: UMIN000037712.

Associations Between Brain-Gut Axis and Psychological Distress in Fibromyalgia: A Microbiota and Magnetic Resonance Imaging Study

An altered brain-gut axis is suspected to be one of the pathomechanisms in fibromyalgia (FM). This cross-sectional study investigated the associations among altered microbiota, psychological distress, and brain functional connectivity (FC) in FM. We recruited 25 FM patients and 25 healthy people in the present study. Psychological distress was measured using standardized questionnaires. Microbiota analysis was performed on the participants' stools. Functional magnetic resonance imaging data were acquired, and seed-based resting-state FC (rs-FC) analysis was conducted with the salience network nodes as seeds. Linear regression and mediation analyses evaluated microbiota, symptoms, and rs-FCs associations. We found altered microbiota diversity in FM, of which Phascolarctobacterium and Lachnoclostridium taxa increased the most and Faecalibacterium taxon decreased the most compared to controls. The Phascolarctobacterium abundance significantly predicted Beck depression inventory (BDI-II) scores in FM (β = 6.83; P = .033). Rs-FCs from salience network nodes were reduced in FM, of which rs-FCs from the right lateral rostral prefrontal cortex (RPFC) to the lateral occipital cortex, superior division right (RPFC-sLOC) could be predicted by BDI-II scores in patients (β = -.0064; P = .0054). In addition, the BDI-II score was a mediator in the association between Phascolarctobacterium abundance and rs-FCs of RPFC-sLOC (ab = -.06; 95% CI: -.16 to -9.10-3). In conclusion, microbial dysbiosis might be associated with altered neural networks mediated by psychological distress in FM, emphasizing the critical role of the brain-gut axis in FM's non-pain symptoms and supporting further analysis of mechanism-targeted therapies to reduce FM symptoms. PERSPECTIVE: Our study suggests microbial dysbiosis might be associated with psychological distress and the altered salience network, supporting the role of brain-gut axis dysfunction in fibromyalgia pathomechanisms. Further targeting therapies for microbial dysbiosis should be investigated to manage fibromyalgia patients in the future.

Enhanced motor network engagement during reward gain anticipation in fibromyalgia

Reward motivation is essential in shaping human behavior and cognition. Both reward motivation and reward brain circuits are altered in chronic pain conditions, including fibromyalgia. In this study of fibromyalgia patients, we used a data-driven independent component analysis (ICA) approach to investigate how brain networks contribute to altered reward processing. From females with fibromyalgia (N = 24) and female healthy controls (N = 24), we acquired fMRI data while participants performed a monetary incentive delay (MID) reward task. After analyzing the task-based fMRI data using ICA to identify networks, we analyzed 3 networks of interest: motor network (left), value-driven attention network, and basal ganglia network. Then, we evaluated correlation coefficients between each network timecourse versus a task-based timecourse which modeled gain anticipation. Compared to controls, the fibromyalgia cohort demonstrated significantly stronger correlation between the left motor network timecourse and the gain anticipation timecourse, indicating the left motor network was more engaged with gain anticipation in fibromyalgia. In an exploratory analysis, we compared motor network engagement during early versus late phases of gain anticipation. Across cohorts, greater motor network engagement (i.e., stronger correlation between network and gain anticipation) occurred during the late timepoint, which reflected enhanced motor preparation immediately prior to response. Consistent with the main results, patients exhibited greater engagement of the motor network during both early and late phases compared with healthy controls. Visual-attention and basal ganglia networks revealed similar engagement in the task across groups. As indicated by post-hoc analyses, motor network engagement was positively related to anxiety and negatively related to reward responsiveness. In summary, we identified enhanced reward-task related engagement of the motor network in fibromyalgia using a novel data-driven ICA approach. Enhanced motor network engagement in fibromyalgia may relate to impaired reward motivation, heightened anxiety, and possibly to altered motor processing, such as restricted movement or dysregulated motor planning.

Reduced Cortico-Cortical Resting-State Connectivity in Sensory Systems Related to Bodily Pain in Juvenile Fibromyalgia

OBJECTIVE

Juvenile-onset fibromyalgia (JFM) is a paradigmatic chronic pain condition for which the underlying neurobiological substrates are poorly understood. This study examined, for the first time, data-driven resting-state functional connectivity (rsFC) alterations in 37 female adolescents with JFM compared with 43 healthy female adolescents and identified associations with bodily pain.

METHODS

Whole-brain voxel-wise rsFC alterations were assessed using the intrinsic connectivity contrast, a measure of node centrality at each voxel, and seed-based analyses for interpretability. We studied the relationship between rsFC alterations in somatosensory systems and the location and extension of bodily pain.

RESULTS

Adolescents with JFM had voxel-wise rsFC reductions in the paracentral lobule (PCL)/primary somatosensory cortex (S1) (T = 4.89, family-wise error corrected p-value (pFWE) < 0.001) and left midcingulate cortex (T = 4.67, pFWE = 0.043). Post hoc analyses revealed reduced rsFC spanning major cortical sensory hubs (T > 4.4, pFWE < 0.030). Cortico-cortical rsFC reductions within PCL/S1 in JFM occurred in locations innervated by bodily areas where the pain was most frequent (F = 3.15; positive false discovery rate = 0.029) and predicted widespread pain (T > 4.4, pFWE < 0.045). Conversely, adolescents with JFM had increases in PCL/S1-thalamus (T = 4.75, pFWE = 0.046) and PCL/S1-anterior insula rsFC (T = 5.13, pFWE = 0.039).

CONCLUSION

Reduced cortico-cortical sensory integration involving PCL/S1 and spanning the sensory systems may underly critical pain sensory features in youth with JFM. Reduced sensory integration is paralleled by augmented cross-talk between sensory and affective/salience-processing regions, potentially indicating a shift toward more affectively colored sensory experiences to the detriment of specific sensory discrimination.

Frequency of idiopathic intracranial hypertension with ultrasound in patients with fibromyalgia: Relation with function, central sensitization, and neuropathic pain

OBJECTIVE

The purpose of this study was to evaluate the prevalence of idiopathic intracranial hypertension (IIH) in fibromyalgia (FMS) patients by utilizing ultrasound to measure the optic nerve sheath diameter (ONSD), a marker of elevated intracranial pressure and also to investigate the relationship with function, fatigue, quality of life (QOL), central sensitization (CS) and neuropathic pain.

METHODS

The study encompassed 80 female FMS patients and 75 healthy controls. Ultrasound was employed to measure the average ONSD in both groups. Conditions potentially elevating intracranial pressure were ruled out following neurological assessments. Pain (via visual analog scale, VAS), function (revised Fibromyalgia Impact Questionnaire, r-FIQ), QOL (Short Form-36, SF-36), fatigue (fatigue severity scale, FACIT), CS (Central Sensitization Scale), and neuropathic pain (Douleur Neuropathique-4) were evaluated.

RESULTS

The average ONSD was significantly higher in the patient group than the control group. Patients with ONSD >5.5 mm consistent with IIH were categorized as Group 1 (n = 54, 67.5%), while those with a diameter of 5.5 mm and below-formed Group 2. VAS pain (p = .033) and FIQ-R scores (p = .033) were significantly higher in Group 1 than Group 2. Headache was found more common in Group 1.

CONCLUSION

This study unveils a substantial occurrence (67.5%) of IIH in FMS patients, suggesting shared pathophysiological mechanisms contributing to symptoms like fatigue, headache, and cognitive dysfunction. Additionally, these findings implicate heightened functional impairment, CS, headache, and fatigue in FMS patients with IIH.

Abnormal functional neurocircuitry underpinning emotional processing in fibromyalgia

Fibromyalgia, a condition characterized by chronic pain, is frequently accompanied by emotional disturbances. Here we aimed to study brain activation and functional connectivity (FC) during processing of emotional stimuli in fibromyalgia. Thirty female patients with fibromyalgia and 31 female healthy controls (HC) were included. Psychometric tests were administered to measure alexithymia, affective state, and severity of depressive and anxiety symptoms. Next, participants performed an emotion processing and regulation task during functional magnetic resonance imaging (fMRI). We performed a 2 × 2 ANCOVA to analyze main effects and interactions of the stimuli valence (positive or negative) and group (fibromyalgia or HC) on brain activation. Generalized psychophysiological interaction analysis was used to assess task-dependent FC of brain regions previously associated with emotion processing and fibromyalgia (i.e., hippocampus, amygdala, anterior insula, and pregenual anterior cingulate cortex [pACC]). The left superior lateral occipital cortex showed more activation in fibromyalgia during emotion processing than in HC, irrespective of valence. Moreover, we found an interaction effect (valence x group) in the FC between the left pACC and the precentral and postcentral cortex, and central operculum, and premotor cortex. These results suggest abnormal brain activation and connectivity underlying emotion processing in fibromyalgia, which could help explain the high prevalence of psychopathological symptoms in this condition.

A Randomized Controlled Neuroimaging Trial of Cognitive Behavioral Therapy for Fibromyalgia Pain

OBJECTIVE

Fibromyalgia (FM) is characterized by pervasive pain-related symptomatology and high levels of negative affect. Mind-body treatments such as cognitive behavioral therapy (CBT) appear to foster improvement in FM via reductions in pain-related catastrophizing, a set of negative, pain-amplifying cognitive and emotional processes. However, the neural underpinnings of CBT's catastrophizing-reducing effects remain uncertain. This randomized controlled mechanistic trial was designed to assess CBT's effects on pain catastrophizing and its underlying brain circuitry.

METHODS

Of 114 enrolled participants, 98 underwent a baseline neuroimaging assessment and were randomized to 8 weeks of individual CBT or a matched FM education control (EDU) condition.

RESULTS

Compared with EDU, CBT produced larger decreases in pain catastrophizing post treatment (P < 0.05) and larger reductions in pain interference and symptom impact. Decreases in pain catastrophizing played a significant role in mediating those functional improvements in the CBT group. At baseline, brain functional connectivity between the ventral posterior cingulate cortex (vPCC), a key node of the default mode network (DMN), and somatomotor and salience network regions was increased during catastrophizing thoughts. Following CBT, vPCC connectivity to somatomotor and salience network areas was reduced.

CONCLUSION

Our results suggest clinically important and CBT-specific associations between somatosensory/motor- and salience-processing brain regions and the DMN in chronic pain. These patterns of connectivity may contribute to individual differences (and treatment-related changes) in somatic self-awareness. CBT appears to provide clinical benefits at least partially by reducing pain-related catastrophizing and producing adaptive alterations in DMN functional connectivity.

Rheumatoid arthritis with concomitant fibromyalgia: The role of ultrasound in assessing disease activity

INTRODUCTION

Fibromyalgia (FM) is a chronic painful condition frequently associated with rheumatoid arthritis (RA), which may falsely increase RA activity. The aim of our study was to compare clinical scoring and ultrasound (US) assessment in RA patients with concomitant FM with those without FM.

METHODS

A cross-sectional study including patients with RA according to the ACR/EULAR 2010 criteria was conducted. Patients were divided into two groups: RA patients meeting ACR 2016 FM criteria (cases) and RA patients not meeting FM criteria (controls). Clinico-biological and US assessments of RA activity were performed on the same day for each patient.

RESULTS

Eighty patients distributed into 40 patients in each group were recruited. Biologic DMARD prescription was more frequent in RA with FM patients than the control group (p = 0.04). DAS28 was significantly greater than DAS28 V3 in RA with FM group (p = 0.002). FM group had significantly less US synovitis (p = 0.035) and less Power Doppler (PD) activity (p = 0.035). Grey scale US score (p = 0.87) and DP US score (p = 0.162) were similar in the two groups. The correlation between the clinical and the ultrasonographic scores was strong to very strong in both groups with the strongest correlation found between DAS28 V3 and US DAS28 V3 (r = 0.95) in RA + FM group.

CONCLUSION

Our study confirms the overestimation of disease activity by the clinical scores in RA with concomitant FM. DAS28 V3 score and US assessment would represent a better alternative.

Topological alterations in white matter structural networks in fibromyalgia

PURPOSE

Neuroimaging studies employing analyses dependent on regional assumptions and specific neuronal circuits could miss characteristics of whole-brain structural connectivity critical to the pathophysiology of fibromyalgia (FM). This study applied the whole-brain graph-theoretical approach to identify whole-brain structural connectivity disturbances in FM.

METHODS

This cross-sectional study used probabilistic diffusion tractography and graph theory analysis to evaluate the topological organization of brain white matter networks in 20 patients with FM and 20 healthy controls (HCs). The relationship between brain network metrics and clinical variables was evaluated.

RESULTS

Compared with HCs, FM patients had lower clustering coefficient, local efficiency, hierarchy, synchronization, and higher normalized characteristic path length. Regionally, patients demonstrated a significant reduction in nodal efficiency and centrality; these regions were mainly located in the prefrontal, temporal cortex, and basal ganglia. The network-based statistical analysis (NBS) identified decreased structural connectivity in a subnetwork of prefrontal cortex, basal ganglia, and thalamus in FM. There was no correlation between network metrics and clinical variables (false discovery rate corrected).

CONCLUSIONS

The current research demonstrated disrupted topological architecture of white matter networks in FM. Our results suggested compromised neural integration and segregation and reduced structural connectivity in FM.

Decreased DTI-ALPS and choroid plexus enlargement in fibromyalgia: a preliminary multimodal MRI study

PURPOSE

The glymphatic system is a fluid exchange pathway that clears waste products that is crucial for the maintenance of brain homeostasis. However, the exact role it plays in the emergence of fibromyalgia (FM) is still not fully understood. Here, we explored the changes in non-invasive MRI proxy probably related to the glymphatic function in FM patients, and explored brain-behavior relationships.

METHODS

A total of 40 participants, consisting of 20 individuals with FM and 20 healthy controls (HCs), were included in the study. The participants underwent structural T1-weighted MRI, diffusion tensor imaging (DTI), and clinical assessment. The data was obtained from an open access dataset. The study compared non-invasive MRI indices, including choroid plexus (CP) volume and DTI analysis along the perivascular space (ALPS), between the FM and HC groups. Furthermore, correlation analysis was conducted to determine the correlation between clinical parameters and both CP volume and DTI-ALPS index.

RESULTS

Patients with FM had significantly higher CP volume and a lower DTI-ALPS index than HCs adjusting for age and intracranial volume. Higher CP volume was associated with lower DTI-ALPS index, and longer disease duration.

CONCLUSION

Our findings demonstrate aberrant glymphatic function in FM, and that dysfunction in the brain glymphatic system may play a role in the neural mechanisms underlying FM.

Large-scale momentary brain co-activation patterns are associated with hyperalgesia and mediate focal neurochemistry and cross-network functional connectivity in fibromyalgia

ABSTRACT

Fibromyalgia has been characterized by augmented cross-network functional communication between the brain's sensorimotor, default mode, and attentional (salience/ventral and dorsal) networks. However, the underlying mechanisms of these aberrant communication patterns are unknown. In this study, we sought to understand large-scale topographic patterns at instantaneous timepoints, known as co-activation patterns (CAPs). We found that a sustained pressure pain challenge temporally modulated the occurrence of CAPs. Using proton magnetic resonance spectroscopy, we found that greater basal excitatory over inhibitory neurotransmitter levels within the anterior insula orchestrated higher cross-network connectivity between the anterior insula and the default mode network through lower occurrence of a CAP encompassing the attentional networks during sustained pain. Moreover, we found that hyperalgesia in fibromyalgia was mediated through increased occurrence of a CAP encompassing the sensorimotor network during sustained pain. In conclusion, this study elucidates the role of momentary large-scale topographic brain patterns in shaping noxious information in patients with fibromyalgia, while laying the groundwork for using precise spatiotemporal dynamics of the brain for the potential development of therapeutics.

Evidence of neuroinflammation in fibromyalgia syndrome: a [ 18 F]DPA-714 positron emission tomography study

ABSTRACT

This observational study aimed to determine whether individuals with fibromyalgia (FM) exhibit higher levels of neuroinflammation than healthy controls (HCs), as measured with positron emission tomography using [ 18 F]DPA-714, a second-generation radioligand for the translocator protein (TSPO). Fifteen women with FM and 10 HCs underwent neuroimaging. Distribution volume (V T ) was calculated for in 28 regions of interest (ROIs) using Logan graphical analysis and compared between groups using multiple linear regressions. Group (FM vs HC) was the main predictor of interest and TSPO binding status (high- vs mixed-affinity) was added as a covariate. The FM group had higher V T in the right postcentral gyrus ( b = 0.477, P = 0.033), right occipital gray matter (GM; b = 0.438, P = 0.039), and the right temporal GM ( b = 0.466, P = 0.042). The FM group also had lower V T than HCs in the left isthmus of the cingulate gyrus ( b = -0.553, P = 0.014). In the subgroup of high-affinity binders, the FM group had higher V T in the bilateral precuneus, postcentral gyrus, parietal GM, occipital GM, and supramarginal gyrus. Group differences in the right parietal GM were associated with decreased quality of life, higher pain severity and interference, and cognitive problems. In support of our hypothesis, we found increased radioligand binding (V T ) in the FM group compared with HCs in several brain regions regardless of participants' TSPO binding status. The ROIs overlapped with prior reports of increased TSPO binding in FM. Overall, increasing evidence supports the hypothesis that FM involves microglia-mediated neuroinflammation in the brain.

Dysfunctional Activation of the Dorsolateral Prefrontal Cortex During Pain Anticipation Is Associated With Altered Subsequent Pain Experience in Fibromyalgia Patients

The ability to accurately predict pain is an adaptive feature in healthy individuals. However, in chronic pain, this mechanism may be selectively impaired and can lead to increased anxiety and excessive avoidance behavior. Recently, we reported the first data demonstrating brain activation in fibromyalgia (FM) patients during conditioned pain responses, in which FM patients revealed a tendency to form new pain-related associations rather than extinguishing irrelevant ones. The aim of the present study was to extend our previous analysis, to elucidate potential neural divergences between subjects with FM (n = 65) and healthy controls (HCs) (n = 33) during anticipatory information (ie, prior to painful stimulus onset). Using functional magnetic resonance imaging (fMRI), the current analyses include 1) a congruently cued paradigm of low and high pain predictive cues, followed by 2) an incongruently cued paradigm where low and high pain predictive cues were followed by an identical mid-intensity painful pressure. During incongruently cued high-pain associations, FM exhibited reduced left dorsolateral prefrontal cortex (dlPFC) activation compared to HCs, which was followed by an altered subsequent pain experience in FM, as patients continued to rate the following painful stimuli as high, even though the pressure had been lowered. During congruently cued low pain anticipation, FM exhibited decreased right dlPFC activation compared to HCs, as well as decreased brain connectivity between brain regions implicated in cognitive modulation of pain (dlPFC) and nociceptive processing (primary somatosensory cortex/postcentral gyrus [S1] and supplementary motor area [SMA]/midcingulate cortex [MCC]). These results may reflect an important feature of validating low pain expectations in HCs and help elucidate behavioral reports of impaired safety processing in FM patients. PERSPECTIVE: FM exhibited a stronger conditioned pain response for high-pain associations, which was associated with reduced dlPFC activation during the incongruent trial. During (congruent and incongruent) low pain associations, FM dlPFC brain activation remained indifferent. Imbalances in threat and safety pain perception may be an important target for psychotherapeutic interventions.

Brain mediators of negative affect-induced physical symptom reporting in patients with functional somatic syndromes

Functional somatic syndromes (FSS) include fibromyalgia, irritable bowel syndrome (IBS), and others. In FSS patients, merely viewing negative affective pictures can elicit increased physical symptoms. Our aim was to investigate the neural mechanisms underlying such negative affect-induced physical symptoms in FSS patients. Thirty patients with fibromyalgia and/or IBS and 30 healthy controls (all women) watched neutral, positive and negative affective picture blocks during functional MRI scanning and rated negative affect and physical symptoms after every block. We compared brain-wide activation during negative versus neutral picture viewing in FSS patients versus controls using robust general linear model analysis. Further, we compared neurologic pain signature (NPS), stimulus intensity-independent pain signature (SIIPS) and picture-induced negative emotion signature (PINES) responses to the negative versus neutral affect contrast and investigated whether they mediated between-group differences in affective picture-induced physical symptom reporting. More physical symptoms were reported after viewing negative compared to neutral pictures, and this effect was larger in patients than controls (p = 0.025). Accordingly, patients showed stronger activation in somatosensory regions during negative versus neutral picture viewing. NPS, but not SIIPS nor PINES, responses were higher in patients than controls during negative versus neutral pictures (p = 0.026). These differential NPS responses partially mediated between-group differences in physical symptoms. In conclusion, picture-induced negative affect elicits physical symptoms in FSS patients as a result of activation of somatosensory and nociceptive brain patterns, supporting the idea that affect-driven alterations in processing of somatic signals is a critical mechanism underlying FSS.

Fused Brain Functional Connectivity Network and Edge-attention Graph Convolution Network for Fibromyalgia Syndrome Diagnosis

Fibromyalgia syndrome (FMS) is a type of rheumatology that seriously affects the normal life of patients. Due to the complex clinical manifestations of FMS, it is challenging to detect FMS. Therefore, an automatic FMS diagnosis model is urgently needed to assist physicians. Brain functional connectivity networks (BFCNs) constructed by resting-state functional magnetic resonance imaging (rs-fMRI) to describe brain functions have been widely used to identify individuals with relevant diseases from normal control (NC). Therefore, we propose a novel model based on BFCN and graph convolutional network (GCN) for automatic FMS diagnosis. Firstly, a novel fused BFCN method is proposed by fusing Pearson's correlation (PC) and low-rank (LR) BFCN, which retains information and reduces data redundancy to construct BFCN. Then we combine the feature of BFCN with non-image information of subjects to obtain nodes and adjacency matrices, which builds a graph with edge attention. Finally, the graph is sent to the GCN layer for FMS diagnosis. Our model is evaluated on the in-house FMS dataset to achieve 82.48% accuracy. The experimental results show that our method outperforms the state-of-the-art competing methods.

Central metabolites and peripheral parameters associated neuroinflammation in fibromyalgia patients: A preliminary study

To identify central metabolites and peripheral measures associated with neuroinflammation in fibromyalgia (FM), we scanned [11C]-(R)-PK11195 positron emission tomography and magnetic resonance spectroscopy in FM patients. We measured associations between neurometabolite levels measured by magnetic resonance spectroscopy and the extent of neuroinflammation inferred by the distribution volume ratios of [11C]-(R)-PK11195 positron emission tomography in 12 FM patients and 13 healthy controls. We also examined the associations between peripheral parameters, such as creatinine and C-reactive protein, and neuroinflammation. In FM patients, we found negative correlations between neuroinflammation and the creatine (Cr)/total creatine (tCr; Cr + phosphocreatine) ratios in the right (r = -0.708, P = .015) and left thalamus (r = -0.718, P = .008). In FM patients, negative correlations were apparent between neuroinflammation and the glutamate/tCr ratio in the right insula (r = -0.746, P = .005). In FM patients, we found negative correlations between neuroinflammation in the left thalamus (r = -0.601, P = .039) and left insula (r = -0.598, P = .040) and the blood creatinine levels. Additionally, we found significant correlations of other peripheral measures with neuroinflammation in FM patients. Our results suggest that both central metabolites, such as Cr and glutamate, and peripheral creatinine and other parameters are associated with neuroinflammation in patients with FM.

Neural correlates of control over pain in fibromyalgia patients

The perceived lack of control over the experience of pain is arguably-one major cause of agony and impaired life quality in patients with chronic pain disorders as fibromyalgia (FM). The way perceived control affects subjective pain as well as the underlying neural mechanisms have so far not been investigated in chronic pain. We used functional magnetic resonance imaging (fMRI) to examine the neural correlates of self-controlled compared to computer-controlled heat pain in healthy controls (HC, n = 21) and FM patients (n = 23). Contrary to HC, FM failed to activate brain areas usually involved in pain modulation as well as reappraisal processes (right ventrolateral (VLPFC), dorsolateral prefrontal cortex (DLPFC) and dorsal anterior cingulate cortex (dACC)). Computer-controlled (compared to self-controlled) heat revealed significant activations of the orbitofrontal cortex (OFC) in HC, whereas FM activated structures that are typically involved in neural emotion processing (amygdala, parahippocampal gyrus). Additionally, FM displayed disrupted functional connectivity (FC) of the VLPFC, DLPFC and dACC with somatosensory and pain (inhibition)-related areas during self-controlled heat stimulation as well as significantly decreased gray matter (GM) volumes compared to HC in DLPFC and dACC. The described functional and structural changes provide evidence for far-reaching impairments concerning pain-modulatory processes in FM. Our investigation represents a first demonstration of dysfunctional neural pain modulation through experienced control in FM according to the extensive functional and structural changes in relevant sensory, limbic and associative brain areas. These areas may be targeted in clinical pain therapeutic methods involving TMS, neurofeedback or cognitive behavioral trainings.

Novel Approaches in Molecular Imaging and Neuroimaging of Fibromyalgia

Fibromyalgia (FM) represents a condition that is still controversial in its entity, pathophysiology, diagnosis and management. The aim of this review is to focus on imaging aspects of FM, especially on novel approaches in molecular imaging, with a special focus on neuroimaging. Novel functional and molecular imaging findings may represent, eventually, future biomarkers both in research settings and in terms of clinical practice. Several imaging techniques have already been tested in clinical trials in the FM field, including functional MRI, positron emission tomography (PET) imaging with ¹⁸F-FDG in FM, PET imaging of the dopaminergic system, PET imaging of the GABAergic system, PET imaging with neuroinflammation and neuroimmune parameters, PET imaging of the opioid system and H₂¹⁵O-PET activation studies. Therefore, the potential role in the FM field of fMRI and different PET tracers has been discussed in different settings, serving as a comprehensive guide of novel imaging options both in research and in the clinical field.

Reduced midbrain raphe echogenicity in patients with fibromyalgia syndrome

OBJECTIVES

The pathogenesis of fibromyalgia syndrome (FMS) is unclear. Transcranial ultrasonography revealed anechoic alteration of midbrain raphe in depression and anxiety disorders, suggesting affection of the central serotonergic system. Here, we assessed midbrain raphe echogenicity in FMS.

METHODS

Sixty-six patients underwent transcranial sonography, of whom 53 were patients with FMS (27 women, 26 men), 13 patients with major depression and physical pain (all women), and 14 healthy controls (11 women, 3 men). Raphe echogenicity was graded visually as normal or hypoechogenic, and quantified by digitized image analysis, each by investigators blinded to the clinical diagnosis.

RESULTS

Quantitative midbrain raphe echogenicity was lower in patients with FMS compared to healthy controls (p<0.05), but not different from that of patients with depression and accompanying physical pain. Pain and FMS symptom burden did not correlate with midbrain raphe echogenicity as well as the presence and severity of depressive symptoms.

CONCLUSION

We found reduced echogenicity of the midbrain raphe area in patients with FMS and in patients with depression and physical pain, independent of the presence or severity of pain, FMS, and depressive symptoms. Further exploration of this sonographic finding is necessary before this objective technique may enter diagnostic algorithms in FMS and depression.

Disrupted White Matter Microstructure in Patients With Fibromyalgia Owing Predominantly to Psychological Factors: A Diffusion Tensor Imaging Study

BACKGROUND

Neuroimaging investigations have already uncovered alterations to cerebral microstructural integrity in patients with fibromyalgia (FM). In the meantime, these patients commonly suffer from depression and anxiety.

OBJECTIVE

In this study, microstructure changes within white matter were examined in patients with FM with consideration of concurrent physiological factors.

STUDY DESIGN

A cross-sectional case-control study.

SETTING

A university hospital.

METHODS

Diffusion tensor imaging was performed on 20 patients with FM and 20 healthy controls. The 4 diffusional indices, namely, fractional anisotropy (FA), mean, radial, and axial diffusivity (MD, RD, AD) were calculated using tract-based spatial statistics. The relationships between the diffusional parameters and pain scales were also examined.

RESULTS

The patients with FM exhibited enhanced FA, reduced MD, RD, and AD in numerous white matter tracts, including the corpus callosum, corona radiata, internal capsule, corticospinal tract, posterior thalamic radiation, cerebellar peduncle, sagittal stratum, and superior fronto-occipital fasciculus. When depression and anxiety were added as covariates, most between-group diffusional difference disappeared except for AD reduction in the corona radiate, internal capsule, and cerebellar peduncle (P < 0.05, threshold-free cluster enhancement corrected). The diffusion tensor imaging measures were not correlated with clinical variables.

LIMITATION

A relatively small sample size.

CONCLUSION

Our results demonstrate that disrupted white matter microstructure in patients with FM is mainly restricted to tracts associated with pain sensory processing and motor control, adjusting for psychosocial factors. A considerable degree of difference in white matter characteristics may be explained by the patients with FM group's greater level of psychological distress.

Altered resting-state functional connectivity within corticostriatal and subcortical-striatal circuits in chronic pain

Brain corticostriatal circuits are important for understanding chronic pain and highly relevant to motivation and cognitive processes. It has been demonstrated that in patients with chronic back pain, altered nucleus accumbens (NAcc)-medial prefrontal cortex (MPFC) circuit fMRI-based activity is predictive of patient outcome. We evaluated the NAcc-MPFC circuit in patients with another chronic pain condition, fibromyalgia, to extend these important findings. First, we compared fMRI-based NAcc-MPFC resting-state functional connectivity in patients with fibromyalgia (N = 32) vs. healthy controls (N = 37). Compared to controls, the NAcc-MPFC circuit's connectivity was significantly reduced in fibromyalgia. In addition, within the fibromyalgia group, NAcc-MPFC connectivity was significantly correlated with trait anxiety. Our expanded connectivity analysis of the NAcc to subcortical brain regions showed reduced connectivity of the right NAcc with mesolimbic circuit regions (putamen, thalamus, and ventral pallidum) in fibromyalgia. Lastly, in an exploratory analysis comparing our fibromyalgia and healthy control cohorts to a separate publicly available dataset from patients with chronic back pain, we identified reduced NAcc-MPFC connectivity across both the patient groups with unique alterations in NAcc-mesolimbic connectivity. Together, expanding upon prior observed alterations in brain corticostriatal circuits, our results provide novel evidence of altered corticostriatal and mesolimbic circuits in chronic pain.

Fibromyalgia impact in the prefrontal cortex subfields: An assessment with MRI

INTRODUCTION

Previous studies have associated brain abnormalities in people with fibromyalgia with accelerated brain ageing. The prefrontal cortex is located in the anterior pole of the mammalian brain. It is defined as the part of the cerebral cortex that receives projections from the mediodorsal nucleus of the thalamus.

AIM

This study aimed to evaluate the volumetric differences in the prefrontal cortex subfields between healthy women and women with fibromyalgia using magnetic resonance imaging (MRI) and controlling for age, estimated intracranial volume, depression, and cognitive impairment.

MATERIAL AND METHODS

A total of 47 women with fibromyalgia (recruited from a fibromyalgia local association) and 43 healthy women (retrieved from the Open Access Series of Imaging Studies database) participated in this cross-sectional study. Multiple linear regressions were used to predict the value of the prefrontal cortex subfields as well as to determine if there were volumetric differences between the groups.

RESULTS

Volume of all prefrontal cortex regions decreased with each year of age. Healthy women showed higher volume in all the prefrontal cortex subfields than women with fibromyalgia. Regarding partial correlations performed, no significant relation were found between the fibromyalgia impact and the brain volumes analyzed, controlling for depression.

CONCLUSIONS

Women with fibromyalgia showed reduced volume in the right caudal middle frontal gyrus, rostral middle frontal gyrus, left inferior frontal gyrus pars opercularis, inferior frontal gyrus pars triangularis, inferior frontal gyrus pars orbitalis, lateral orbitofrontal cortex, right medial orbitofrontal cortex, right rostral anterior cingulate gyrus subfields of the prefrontal cortex and total gray matter compared to healthy women. Furthermore, through an analysis of multiple linear regressions, the left rostral middle frontal gyrus and left lateral orbitofrontal cortex showed significantly volumetric decreases related to depression levels. The total gray matter also shows a significant decrease related to age observed through the analysis of multiple linear regressions. No significant relation were found between the impact of the disease and the brain volumes analyzed, controlling for depression in women with fibromyalgia.

Distinct aberrations in cerebral pain processing differentiating patients with fibromyalgia from patients with rheumatoid arthritis

ABSTRACT

The current study used functional magnetic resonance imaging to directly compare disease-relevant cerebral pain processing in well-characterized patient cohorts of fibromyalgia (FM, nociplastic pain) and rheumatoid arthritis (RA, nociceptive pain). Secondary aims were to identify pain-related cerebral alterations related to the severity of clinical symptoms such as pain intensity, depression, and anxiety. Twenty-six patients with FM (without RA-comorbidity) and 31 patients with RA (without FM-comorbidity) underwent functional magnetic resonance imaging while stimulated with subjectively calibrated painful pressures corresponding to a pain sensation of 50 mm on a 100-mm visual analogue scale. Stimulation sites were at the most inflamed proximal interphalangeal joint in the left hand in patients with RA and the left thumbnail in patients with FM, 2 sites that have previously been shown to yield the same brain activation in healthy controls. The current results revealed disease-distinct differences during pain modulation in RA and FM. Specifically, in response to painful stimulation, patients with FM compared to patients with RA exhibited increased brain activation in bilateral inferior parietal lobe (IPL), left inferior frontal gyrus (IFG)/ventrolateral prefrontal cortex (vlPFC) encapsulating left dorsolateral prefrontal cortex, and right IFG/vlPFC. However, patients with RA compared to patients with FM exhibited increased functional connectivity (during painful stimulation) between right and left IPL and sensorimotor network and between left IPL and frontoparietal network. Within the FM group only, anxiety scores positively correlated with pain-related brain activation in left dorsolateral prefrontal cortex and right IFG/vlPFC, which further highlights the complex interaction between affective (ie, anxiety scores) and sensory (ie, cerebral pain processing) dimensions in this patient group.

Thermal imaging ruled out as a supplementary assessment in patients with fibromyalgia: A cross-sectional study

BACKGROUND

The diagnosis of fibromyalgia syndrome (FMS) syndrome is often complicated and relies on diagnostic criteria based mostly on the symptoms reported by patients. Implementing objective complementary tests would be desirable to better characterize this population.

OBJECTIVE

The purpose of this cross-sectional study was to compare the skin temperature at rest using thermography in women with FMS and healthy women.

METHODS

Eighty-six women with FMS and 92 healthy controls volunteered to participate. The temperature of all participants was measured by infra-red thermography, registering the skin surface temperature (minimum, maximum and average) at rest in different areas: neck, upper and lower back, chest, knees and elbows. In order to analyze the differences in the skin temperature between groups, inferential analyses of the data were performed using Mann-Whitney U test.

RESULTS

The results showed no significant difference in skin temperature between groups in the neck, upper back, chest and elbows (p>0.05). The lower back and knees areas showed significant differences between groups (p<0.05), although these differences did not reach a minimum of clinically detectable change.

CONCLUSIONS

Women with fibromyalgia presented no clinically meaningful reduction or difference in skin temperature at rest when compared with a group of healthy women. The infra-red thermography is not an effective supplementary assessment tool in women with fibromyalgia.

A picture is worth a thousand words: linking fibromyalgia pain widespreadness from digital pain drawings with pain catastrophizing and brain cross-network connectivity

ABSTRACT

Pain catastrophizing is prominent in chronic pain conditions such as fibromyalgia and has been proposed to contribute to the development of pain widespreadness. However, the brain mechanisms responsible for this association are unknown. We hypothesized that increased resting salience network (SLN) connectivity to nodes of the default mode network (DMN), representing previously reported pain-linked cross-network enmeshment, would be associated with increased pain catastrophizing and widespreadness across body sites. We applied functional magnetic resonance imaging (fMRI) and digital pain drawings (free-hand drawing over a body outline, analyzed using conventional software for multivoxel fMRI analysis) to investigate precisely quantified measures of pain widespreadness and the associations between pain catastrophizing (Pain Catastrophizing Scale), resting brain network connectivity (Dual-regression Independent Component Analysis, 6-minute multiband accelerated fMRI), and pain widespreadness in fibromyalgia patients (N = 79). Fibromyalgia patients reported pain in multiple body areas (most frequently the spinal region, from the lower back to the neck), with moderately high pain widespreadness (mean ± SD: 26.1 ± 24.1% of total body area), and high pain catastrophizing scale scores (27.0 ± 21.9, scale range: 0-52), which were positively correlated (r = 0.26, P = 0.02). A whole-brain regression analysis focused on SLN connectivity indicated that pain widespreadness was also positively associated with SLN connectivity to the posterior cingulate cortex, a key node of the DMN. Moreover, we found that SLN-posterior cingulate cortex connectivity statistically mediated the association between pain catastrophizing and pain widespreadness (P = 0.01). In conclusion, we identified a putative brain mechanism underpinning the association between greater pain catastrophizing and a larger spatial extent of body pain in fibromyalgia, implicating a role for brain SLN-DMN cross-network enmeshment in mediating this association.

Investigation of thermal changes in the thyroid gland region of individuals with hypothyroidism and fibromyalgia by analyzing the temperature of brown adipose tissue

This exploratory retrospective study aims to investigate the thermal changes in the thyroid gland region of patients with hypothyroidism and fibromyalgia by analyzing the temperature of the brown adipose tissue (BAT). A total of 166 individuals from 1000 thermographic electronic medical records were classified into four groups: Group HP + FM-50 individuals with hypothyroidism and fibromyalgia; Group FM-56 individuals with fibromyalgia only; Group HP-30 individuals with hypothyroidism only, and Group Control-30 healthy individuals. The thermal images from the electronic medical records were acquired by a FLIR T650SC infrared camera (used for thermometry) and the temperature data for each group were statistically analyzed. Group HP + FM showed r = 0, meaning that the average temperatures of the thyroid and BAT are independent of each other. Groups FM, HP and Control showed r = 1, meaning that the average temperatures of the thyroid and BAT were directly related. Our findings showed that the average temperatures of the thyroid and BAT regions are similar. Also, there was no correlation between thyroid gland temperature and the presence of hypothyroidism or fibromyalgia using thermometry.

Feasibility of Auricular Field Stimulation in Fibromyalgia: Evaluation by Functional Magnetic Resonance Imaging, Randomized Trial

OBJECTIVE

To evaluate the feasibility of recruitment, preliminary efficacy, and acceptability of auricular percutaneous electrical nerve field stimulation (PENFS) for the treatment of fibromyalgia in veterans, using neuroimaging as an outcome measure and a biomarker of treatment response.

DESIGN

Randomized, controlled, single-blind.

SETTING

Government hospital.

SUBJECTS

Twenty-one veterans with fibromyalgia were randomized to standard therapy (ST) control or ST with auricular PENFS treatment.

METHODS

Participants received weekly visits with a pain practitioner over 4 weeks. The PENFS group received reapplication of PENFS at each weekly visit. Resting-state functional connectivity magnetic resonance imaging (rs-fcMRI) data were collected within 2 weeks prior to initiating treatment and 2 weeks following the final treatment. Analysis of rs-fcMRI used a right posterior insula seed. Pain and function were assessed at baseline and at 2, 6, and 12 weeks post-treatment.

RESULTS

At 12 weeks post-treatment, there was a nonsignificant trend toward improved pain scores and significant improvements in pain interference with sleep among the PENFS treatment group as compared with the ST controls. Neuroimaging data displayed increased connectivity to areas of the cerebellum and executive control networks in the PENFS group as compared with the ST control group following treatment.

CONCLUSIONS

There was a trend toward improved pain and function among veterans with fibromyalgia in the ST + PENFS group as compared with the ST control group. Pain and functional outcomes correlated with altered rs-fcMRI network connectivity. Neuroimaging results differed between groups, suggesting an alternative underlying mechanism for PENFS analgesia.

Should a Coexisting or Suspected Diagnosis of Fibromyalgia Affect the Decision to Perform Diagnostic Blocks for Patients with Chronic Noncancer Pain - Results from an Observational Research Study

BACKGROUND

Diagnostic injections (blocks) are a valuable tool in the management of chronic noncancer pain. By precise blockade of specific neural structures and observation of pain responses, pain mechanisms can be accurately defined. With such information, therapeutic procedures targeting neural structures are possible. Fibromyalgia is a disorder of pain processing with characteristic symptoms. The 2010 American College of Rheumatologists fibromyalgia diagnostic criteria evaluates these symptoms in a scoring system, allowing more objectivity in the diagnosis. We hypothesize that patients with fibromyalgia phenotype fulfilling the 2010 American College of Rheumatologists criteria may respond to diagnostic blocks differently when compared to patients without fibromyalgia phenotype.

OBJECTIVES

This study was designed to establish whether diagnosis or suspected diagnosis of fibromyalgia should influence the decision to perform diagnostic blocks for chronic non-cancer pain.

STUDY DESIGN

A prospective observational research study was performed at our institution. IRAS project ID: 231514.

SETTING

Tertiary pain clinic in the UK.

METHODS

Patients were selected to receive diagnostic block by usual clinical assessment after which they were asked to consent to take part in the study. All participating patients completed the 2010 American College of Rheumatologists fibromyalgia diagnostic questionnaire prior to the diagnostic block. Patients were divided into 2 groups A and B based on the outcome of block - primary outcome. Group A experienced a 70% or greater improvement in pain severity following the block for the anticipated duration of action of the local anesthetic, Group B experienced a less than 70% reduction in pain. Statistical analysis between groups A and B was conducted by comparing categorical data, described as percentages, with the chi squared test. Ordinal variables such as Widespread pain index and Symptom severity score are presented as median and analyzed with Mann-Whitney test.

RESULTS

Seventy-seven patients were included in the study. Two patients were lost to follow-up. Of the 75 remaining patients, 44 received lumbar medial branch blocks, 19 genicular nerve blocks, 3 blocks to nerves supplying the sacroiliac joint, one suprascapular nerve block, and 6 cervical and 2 thoracic medial branch blocks. Group A contained 38 patients and group B contained 37 patients. There was no statistically significant difference in the prevalence of fibromyalgia screening questionnaire positive patients between groups A (13 out of 38 patients) and B (13 out of 37 patients), P = 0.93. There was no statistically significant difference in the prevalence of fibromyalgia screening questionnaire positive patients in subgroups undergoing the same type of diagnostic block (spinal pain and knee pain).

LIMITATIONS

Selection of patients prior to inclusion in the study may introduce bias. Patients were selected by individual treating clinicians using usual clinical practice; however, the exact selection criteria were not standardized.

CONCLUSION

We conclude that after physician selection, the presence of fibromyalgia phenotype does not influence the outcome from diagnostic block. It is likely therefore that fibromyalgia phenotype should not influence the decision to perform diagnostic blocks if indicated based on assessment by an experienced pain physician.

Ultrasound Assessment of Disease Activity Prevents Disease-Modifying Antirheumatic Drug (DMARD) Escalation and May Reduce DMARD-Related Direct Costs in Rheumatoid Arthritis With Fibromyalgia: An Exploratory Study

OBJECTIVES

as an objective measure, ultrasound (US) could prevent rheumatoid arthritis (RA) overtreatment induced by concomitant fibromyalgia (FM). Our goal was to study how patients with RA and FM who underwent a US examination differed from those without a US examination in terms of overall disease-modifying antirheumatic drug (DMARD) escalation and biologic DMARD-related direct costs.

METHODS

Patients with RA and FM were seen between 2011 and 2017. In cases of 28-joint Disease Activity Score (DAS28) overestimation, patients were referred to undergo a US examination. The US group underwent a US examination to confirm disease activity, and the DAS28 group had disease activity assessment based solely on the DAS28.

RESULTS

Of 230 patients with RA, 22 women with RA and FM (DAS28 group, n = 9; and US group, n = 13) were seen in 316 visits (115.68 patient-years). The DMARD treatment was escalated in 27.1% of visits in the DAS28 group versus 17.3% in the US group (P = .046). The relative risk of DMARD escalation in the DAS28 group compared to the US group was 1.57 (95% confidence interval, 1.01-2.43). In sum total, US$240,784.52 were spent on biologics throughout the entire study period. Basing biologic DMARD prescriptions on US results could save an average of US$405.66 per patient-year.

CONCLUSIONS

In this real-life study of patients with RA and FM, a US examination was associated with less DMARD escalation and could reduce biologic DMARD direct costs. Specifically, synovitis as scored by power Doppler US could be useful as a treatment target for RA in patients with DAS28 overestimation due to FM, but further studies are necessary.

Machine Learning Diagnostic Modeling for Classifying Fibromyalgia Using B-mode Ultrasound Images

Fibromyalgia (FM) diagnosis remains a challenge for clinicians due to a lack of objective diagnostic tools. One proposed solution is the use of quantitative ultrasound (US) techniques, such as image texture analysis, which has demonstrated discriminatory capabilities with other chronic pain conditions. From this, we propose the use of image texture variables to construct and compare two machine learning models (support vector machine [SVM] and logistic regression) for differentiating between the trapezius muscle in healthy and FM patients. US videos of the right and left trapezius muscle were acquired from healthy (n = 51) participants and those with FM (n = 57). The videos were converted into 64,800 skeletal muscle regions of interest (ROIs) using MATLAB. The ROIs were filtered by an algorithm using the complex wavelet structural similarity index (CW-SSIM), which removed ROIs that were similar. Thirty-one texture variables were extracted from the ROIs, which were then used in nested cross-validation to construct SVM and elastic net regularized logistic regression models. The generalized performance accuracy of both models was estimated and confirmed with a final validation on a holdout test set. The predicted generalized performance accuracy of the SVM and logistic regression models was computed to be 83.9 ± 2.6% and 65.8 ± 1.7%, respectively. The models achieved accuracies of 84.1%, and 66.0% on the final holdout test set, validating performance estimates. Although both machine learning models differentiate between healthy trapezius muscle and that of patients with FM, only the SVM model demonstrated clinically relevant performance levels.

Neurogenic Thoracic Outlet Syndrome and other Forms of Cervical Brachial Syndrome Treated with Plasma Concentrate Enriched for Alpha 2 Macroglobulin

BACKGROUND

Existing therapies for myofascial and neuralgic forms of cervicobrachial pain may have unsatisfactory outcomes. Alternative therapies may be considered, particularly for individuals who have failed to respond. Contemporary conceptualizations of chronic pain mechanisms include the contribution of inflammatory factors; therefore, locally targeted antiinflammatory administrations may play a role in treatment of cervicobrachial pain.Alpha 2 macroglobulin (A2M) is a plasma protein that acts as a molecular trap for inflammatory factors such as tumor necrosis factor. After plasma is enriched for A2M, it may be considered as a possible injectable agent to counteract inflammation that may occur with a cervicobrachial pain syndrome.

OBJECTIVES

This retrospective review evaluates patient response to the use of plasma concentrate enriched for alpha 2 macroglobulin (A2M-PPP) in treatment of neurogenic thoracic outlet syndrome (TOS) and other forms of cervical brachial syndrome.

STUDY DESIGN

Observational Study.

SETTING

Outpatient interventional neurology practice.

METHODS

There were 62 patients, including 46 women and 16 men ages 23-77 years. Twenty-three of these patients were diagnosed with complex regional pain syndrome (CRPS) or fibromyalgia, 18 with TOS, and 21 with musculotendinous pain (MTP). At baseline, 1 month, 3 months, and 6 months, patient status was evaluated with a Brief Pain Inventory (BPI) that included a composite pain score and a functional interference score. Patients were asked to estimate overall satisfaction with a Patient Global Impression of Change (PGIC) scale. Criterion for clinically significant improvement included >30% betterment in the BPI pain and functional interference subscales and a PGIC of > 5 at the 3-month mark.

RESULTS

Three patients, one with CRPS and 2 with TOS, complained of several days of worsened pain or dysesthesias. No serious or permanent complications were encountered. For patients with TOS at the 3-month mark, 61% achieved clinical endpoints of success compared with 35% with CRPS/fibromyalgia and 24% for patients with MTP (P < 0.05, chi-square). By 6 months, 22% of individuals in the neuropathic TOS group had > 30% improvements in pain and functional interference scores compared with 13% of the individuals in the CRPS/fibromyalgia group and 18% in the MTP group.

LIMITATIONS

This article does not differentiate the added benefit of A2M-PPP from hydrodissection alone. Additionally, this article does not evaluate the actual benefit of the A2M molecule apart from other factors present in the platelet-poor concentrate such as exosomes and cytokines. With the advent of pure engineered A2M, more focused studies will be possible. Also, an independent assay was not done, and therefore we cannot be precisely sure about the exact quantity of platelets, if any, which were contained in the platelet-poor concentration.

CONCLUSIONS

Results suggest that A2M-PPP, when injected into muscle, tendon, and epineurium with live ultrasound guidance, appears to be relatively safe and free of postinjection inflammatory reactions that are often seen after platelet-poor plasma injection. A2M-PPP appears to be associated more frequently with good outcomes when injected into brachial plexus targets in patients with TOS compared with outcomes observed after injection of the plexus in patients with CRPS/fibromyalgia.

KEY WORDS

Plasma concentrate enriched for alpha 2 macroglobulin, neurogenic thoracic outlet syndrome, cervical brachial syndrome.

Assessment of enthesis in patients with psoriatic arthritis and fibromyalgia using clinical examination and ultrasound

OBJECTIVES

The primary aim of this study was to compare the prevalence of clinical and particularly ultrasonographic signs of enthesitis in patients with psoriatic arthritis (PsA), fibromyalgia (FM), or both. The secondary aim was to assess the impact of FM on disease activity and clinimetric scores.

METHODS

This single-centre, observational cross-sectional study involved 101 consenting patients: 39 with PsA (CASPAR criteria), 23 with FM (2016 criteria), and 39 with both. Standard PsA and FM clinical, laboratory and clinimetric data were recorded, and entheses were assessed using the Leeds Enthesitis Index (LEI) and the Maastricht Ankylosing Spondylitis Enthesitis Score (MASES). All of the patients underwent B mode (grey scale) and Power Doppler (PD) ultrasonography bilaterally at the insertions of the quadriceps tendons, the proximal and distal patellar tendons, the Achilles tendons, and the plantar fascia insertions of the calcaneus, to evaluate the thickness of entheses, the hypoechogenicity, the presence of bony erosions, the enthesophytes, and the bursitis. The US findings were scored using the Glasgow Ultrasound Enthesitis Scoring System (GUESS). The data were statistically analysed using univariate and multivariate analyses, and receiver-operating characteristic (ROC) curves, concentrating on the shared clinical features of the two condition.

RESULTS

The mean age of the patients as a whole was 53.6±9.47 years. Females accounted for 64.1% of the PsA patients (disease duration 9.13 years), 95.6% of the FM patients (disease duration 5.09 years), and 92.3% of the patients with PsA-FM (disease duration 7.9 years). There were no between-group differences in the patients' body mass index (BMI). In accordance with the study inclusion criteria, none of the FM subjects had PsA or reported any personal or family history of psoriasis. The mean Psoriasis Area and Severity Index was 2.3±3.1 in the PsA group, and 1.2±2.45 in the PsA-FM group. Clinical evidence of enthesopathy was found in 43% of the patients with PsA, 51.3% of those with PsA-FM, and 50.8% of those with FM, while US entheseal abnormalities were detected in respectively 77%, 74% and 35%. The median Bath Ankylosing Spondylitis Disease Activity Index was significantly higher in the patients with PsA-FM than in those with PsA (7.7 [IQR 2.1] vs. 5.0 [IQR 3.8]; p<0.001), as was the median ESR-assessed Ankylosing Spondylitis Disease Activity Score (3.69 [IQR 1.00] vs. 2.82 [IQR 1.55; p=0.004), or CRP- assessed (median 3.27 [IQR 1.07] vs. 2.66 [IQR 1.26]; p=0.006). There was a correlation between GUESS scores and disease duration in the patients with PsA (rho=0.37; p=0.019, 95% CI 0.10-0.61) or PsA-FM (rho=0.38; p=0.016, 95% CI 0.10-0.61), but not in the FM group, and GUESS scores correlated with BMI (rho=0.2; p=0.05, 95% CI 0.00-0.37) and dyslipidemia (rho=0.34; p=0.006, 95% CI 0.11-0.58) in all three groups.

CONCLUSIONS

The use of a clinical examination and clinimetric scores alone may overestimate active enthesitis in FM patients. As US was more frequently positive in patients with PsA and PsA-FM than in those with FM, it may be useful in differentiating pain due to enthesitis from entheseal pain due to FM.

Comparison of complex regional pain syndrome and fibromyalgia: Differences in beta and gamma bands on quantitative electroencephalography

Complex regional pain syndrome (CRPS) and fibromyalgia (FM) share many features. Both can cause severe pain and are considered to have a mechanism of action, including dysfunction of the sympathetic nervous system. However, they have clinical differences in pain range and degree. The present study aimed to find neurophysiologic differences between CRPS and FM using quantitative electroencephalography (QEEG). Thirty-eight patients with CRPS and 33 patients with FM were included in the analysis. Resting-state QEEG data were grouped into frontal, central, and posterior regions to analyze for regional differences. General linear models were utilized to test for group differences in absolute and relative powers. As a result, the CRPS group relative to FM group showed lower total absolute powers in the beta band (F = 5.159, P < .05), high beta (F = 14.120, P < .05), and gamma band (F = 15.034, P < .05). There were no significant differences between 2 groups in the delta, theta, and alpha bands. The present findings show that the CRPS and FM groups differ mainly in the high frequency, which may reflect their distinct pathophysiology and symptomatology. Our study suggests that the QEEG differences can be clinically useful in assessing brain function in patients with CRPS and FM.

[Neuroimaging in fibromyalgia]

INTRODUCTION

Most current research suggests that fibromyalgia is a disease produced by an alteration in the processing of pain signals in the central nervous system. In recent years, advances in non- or minimally-invasive brain imaging techniques have made it possible to discover how different areas of the nervous system are involved in the aetiopathogenesis of diseases that up until now have been considered as having a functional profile.

AIM

To describe the objectified functional and the structural changes that take place in the brains of patients with fibro-myalgia by means of the currently available neuroimaging techniques.

DEVELOPMENT

This work reviews the clinical studies, both anatomical and molecular, that have been conducted to date in the field of fibromyalgia using different brain imaging techniques.

CONCLUSIONS

Different, but related, areas of the central nervous system have been described as altering not only the functional but also the structural form, in patients with fibromyalgia. These involved areas extend beyond the pain circuits, which would explain the variety of symptoms in patients, in addition to the characteristic pain reported by them.

Cerebral blood flow variability in fibromyalgia syndrome: Relationships with emotional, clinical and functional variables

OBJECTIVE

This study analyzed variability in cerebral blood flow velocity (CBFV) and its association with emotional, clinical and functional variables and medication use in fibromyalgia syndrome (FMS).

METHODS

Using transcranial Doppler sonography, CBFV were bilaterally recorded in the anterior (ACA) and middle (MCA) cerebral arteries of 44 FMS patients and 31 healthy individuals during a 5-min resting period. Participants also completed questionnaires assessing pain, fatigue, insomnia, anxiety, depression and health-related quality of life (HRQoL).

RESULTS

Fast Fourier transformation revealed a spectral profile with four components: (1) a first very low frequency (VLF) component with the highest amplitude at 0.0024 Hz; (2) a second VLF component around 0.01-to-0.025 Hz; (3) a low frequency (LF) component from 0.075-to-0.11 Hz; and (4) a high frequency (HF) component with the lowest amplitude from 0.25-to-0.35 Hz. Compared to controls, FMS patients exhibited lower LF and HF CBFV variability in the MCAs (p < .005) and right ACA (p = .03), but higher variability at the first right MCA (p = .04) and left ACA (p = .005) VLF components. Emotional, clinical and functional variables were inversely related to LF and HF CBFV variability (r≥-.24, p≤.05). However, associations for the first VLF component were positive (r≥.28, p≤.05). While patients´ medication use was associated with lower CBFV variability, comorbid depression and anxiety disorders were unrelated to variability.

CONCLUSIONS

Lower CBFV variability in the LF and HF ranges were observed in FMS, suggesting impaired coordination of cerebral regulatory systems. CBFV variability was differentially associated with clinical variables as a function of time-scale, with short-term variability being related to better clinical outcomes. CBFV variability analysis may be a promising tool to characterize FMS pathology and it impact on facets of HRQoL.

Functional MRI in rheumatic diseases with a focus on fibromyalgia

Pain is the most common symptom in rheumatic diseases. However, the severity of pain does not correlate with pathology. The lack of an objective test for pain results in clinicians consider pain in patients with fibromyalgia as psychological. Research over the last two decade using functional neuroimaging especially functional MRI scan have demonstrated objectively that patients with fibromyalgia were not malingering. Pain processing is complex and multiple regions of the brain are involved. One consistent finding is decrease activity in regions of the brain involved in pain inhibitory pathways suggesting this is one of the fundamental pathophysiology processes in fibromyalgia.

Brain signature and functional impact of centralized pain: a multidisciplinary approach to the study of chronic pelvic pain (MAPP) network study

Chronic pain is often measured with a severity score that overlooks its spatial distribution across the body. This widespread pain is believed to be a marker of centralization, a central nervous system process that decouples pain perception from nociceptive input. Here, we investigated whether centralization is manifested at the level of the brain using data from 1079 participants in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain Research Network (MAPP) study. Participants with a clinical diagnosis of urological chronic pelvic pain syndrome (UCPPS) were compared to pain-free controls and patients with fibromyalgia, the prototypical centralized pain disorder. Participants completed questionnaires capturing pain severity, function, and a body map of pain. A subset (UCPPS N = 110; fibromyalgia N = 23; healthy control N = 49) underwent functional and structural magnetic resonance imaging. Patients with UCPPS reported pain ranging from localized (pelvic) to widespread (throughout the body). Patients with widespread UCPPS displayed increased brain gray matter volume and functional connectivity involving sensorimotor and insular cortices (P < 0.05 corrected). These changes translated across disease diagnoses as identical outcomes were present in patients with fibromyalgia but not pain-free controls. Widespread pain was also associated with reduced physical and mental function independent of pain severity. Brain pathology in patients with centralized pain is related to pain distribution throughout the body. These patients may benefit from interventions targeting the central nervous system.

Altered cerebral blood flow velocity features in fibromyalgia patients in resting-state conditions

The aim of this study is to characterize in resting-state conditions the cerebral blood flow velocity (CBFV) signals of fibromyalgia patients. The anterior and middle cerebral arteries of both hemispheres from 15 women with fibromyalgia and 15 healthy women were monitored using Transcranial Doppler (TCD) during a 5-minute eyes-closed resting period. Several signal processing methods based on time, information theory, frequency and time-frequency analyses were used in order to extract different features to characterize the CBFV signals in the different vessels. Main results indicated that, in comparison with control subjects, fibromyalgia patients showed a higher complexity of the envelope CBFV and a different distribution of the power spectral density. In addition, it has been observed that complexity and spectral features show correlations with clinical pain parameters and emotional factors. The characterization features were used in a lineal model to discriminate between fibromyalgia patients and healthy controls, providing a high accuracy. These findings indicate that CBFV signals, specifically their complexity and spectral characteristics, contain information that may be relevant for the assessment of fibromyalgia patients in resting-state conditions.

Bone mineral density is decreased in fibromyalgia syndrome: a systematic review and meta-analysis

Previous studies have shown that fibromyalgia syndrome (FMS) is associated with low level of physical activity and exercise, which may lead to an increased risk of osteoporosis. However, studies of bone mineral density (BMD) in fibromyalgia have shown conflicting results. Thus, we conducted a systematic review and meta-analysis to better characterize the association between FMS and BMD. A comprehensive search of the databases MEDLINE and EMBASE was performed from inception through May 2016. The inclusion criterion was the observational studies' assessment of the association between fibromyalgia and bone mineral density in adult subjects. Fibromyalgia was diagnosed in accordance with the American College of Rheumatology criteria for the diagnosis of fibromyalgia syndrome. BMD was measured at the lumbar spine and femoral neck by dual-energy X-ray absorptiometry. Pooled mean difference (MD) of BMD at each site and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method. The between-study heterogeneity of effect size was quantified using the Q statistic and I ². Data were extracted from four observational studies involving 680 subjects. At lumbar spine (L2-L4), BMD is significantly decreased in patients with FMS compared with controls with pooled MD of -0.02 (95% CI -0.03 to -0.01, P value = 0.003, I ² = 0%) (Fig. 1). At femoral neck, BMD is not significantly decreased in patients with FMS compared with controls with pooled MD of 0.01 (95% CI -0.02 to 0.01, P value = 0.23, I ² = 0%) (Fig. 2). In this meta-analysis, we observe that BMD at lumbar spine is decreased in FMS compared with normal individuals. Patients with FMS should be assessed for risk of osteoporosis. Fig. 1 Forest plot of bone mineral density at the lumbar spine, for patients with and without fibromyalgia syndrome. CI-confidence interval Fig. 2 Forest plot of bone mineral density at the femoral neck, for patients with and without fibromyalgia syndrome. CI-confidence interval.

Fibromyalgia Is Correlated with Retinal Nerve Fiber Layer Thinning

OBJECTIVE

To investigate whether fibromyalgia induces axonal damage in the optic nerve that can be detected using optical coherence tomography (OCT), as the retinal nerve fiber layer (RNFL) is atrophied in patients with fibromyalgia compared with controls.

METHODS

Fibromyalgia patients (n = 116) and age-matched healthy controls (n = 144) were included in this observational and prospective cohort study. All subjects underwent visual acuity measurement and structural analysis of the RNFL using two OCT devices (Cirrus and Spectralis). Fibromyalgia patients were evaluated according to Giesecke's fibromyalgia subgroups, the Fibromyalgia Impact Questionnaire (FIQ), and the European Quality of Life-5 Dimensions (EQ5D) scale. We compared the differences between fibromyalgia patients and controls, and analyzed the correlations between OCT measurements, disease duration, fibromyalgia subgroups, severity, and quality of life. The impact on quality of life in fibromyalgia subgroups and in patients with different disease severity was also analyzed.

RESULTS

A significant decrease in the RNFL was detected in fibromyalgia patients compared with controls using the two OCT devices: Cirrus OCT ganglion cell layer analysis registered a significant decrease in the minimum thickness of the inner plexiform layer (74.99±16.63 vs 79.36±3.38 μm, respectively; p = 0.023), nasal inferior, temporal inferior and temporal superior sectors (p = 0.040; 0.011 and 0.046 respectively). The Glaucoma application of the Spectralis OCT revealed thinning in the nasal, temporal inferior and temporal superior sectors (p = 0.009, 0.006, and 0.002 respectively) of fibromyalgia patients and the Axonal application in all sectors, except the nasal superior and temporal sectors. The odds ratio (OR) to estimate the size effect of FM in RNFL thickness was 1.39. RNFL atrophy was detected in patients with FIQ scores <60 (patients in early disease stages) compared with controls in the temporal inferior sector (78.74±17.75 vs 81.65±3.61; p = 0.020) and the temporal superior sector (78.20±14.50 vs 80.74±3.88; p = 0.039) with Cirrus OCT; in the temporal inferior sector (145.85±24.32 vs 150.18±19.71; p = 0.012) and temporal superior sector (131.54±20.53 vs 138.13±16.67; p = 0.002) with the Glaucoma application of the Spectralis OCT; and in all sectors, except the average, nasal superior, and temporal sectors, and parameters with the Axonal application of the Spectralis OCT. Temporal inferior RNFL thickness was significantly reduced in patients with severe fibromyalgia (FIQ≥60) compared with patients with mild fibromyalgia (FIQ<60; 145.85±24.32 vs 138.99±18.09 μm, respectively; 145.43±13.21 vs 139.85±13.09 μm, p = 0.032 with the Glaucoma application and p = 0.021 with the Axonal application). The subgroup with biologic fibromyalgia exhibited significant thinning in the temporal inferior and superior sectors (115.17±20.82 μm and 117.05±24.19 μm, respectively) compared with the depressive (130.83±22.97 μm and 127.71±26.10 μm, respectively) and atypical (128.60±26.54 μm and 125.55±23.65 μm, respectively) subgroups (p = 0.005 and 0.001 respectively).

CONCLUSIONS

Fibromyalgia causes subclinical axonal damage in the RNFL that can be detected using innocuous and non-invasive OCT, even in the early disease stages. The impact on the RNFL in the temporal sectors is greater in patients with biologic fibromyalgia, suggesting the presence of neurodegenerative processes in this subgroup of patients with fibromyalgia.

Altered fMRI resting-state connectivity in individuals with fibromyalgia on acute pain stimulation

BACKGROUND

Fibromyalgia is a chronic widespread pain condition, with patients commonly reporting other symptoms such as sleep difficulties, memory complaints and fatigue. The use of magnetic resonance imaging (MRI) in fibromyalgia has allowed for the detection of neural abnormalities, with alterations in brain activation elicited by experimental pain and alterations in resting state connectivity related to clinical pain.

METHODS

In this study, we sought to monitor state changes in resting brain connectivity following experimental pressure pain in fibromyalgia patients and healthy controls. Twelve fibromyalgia patients and 15 healthy controls were studied by applying discrete pressure stimuli to the thumbnail bed during MRI. Resting-state functional MRI scanning was performed before and immediately following experimental pressure pain. We investigated changes in functional connectivity to the thalamus and the insular cortex.

RESULTS

Acute pressure pain increased insula connectivity to the anterior cingulate and the hippocampus. Additionally, we observed increased thalamic connectivity to the precuneus/posterior cingulate cortex, a known part of the default mode network, in patients but not in controls. This connectivity was correlated with changes in clinical pain.

CONCLUSIONS

These data reporting changes in resting-state brain activity following a noxious stimulus suggest that the acute painful stimuli may contribute to the alteration of the neural signature of chronic pain. WHAT DOES THIS STUDY/ADD?: In this study acute pain application shows an echo in functional connectivity and clinical pain changes in chronic pain.

Interface Management between General Practitioners and Rheumatologists-Results of a Survey Defining a Concept for Future Joint Recommendations

OBJECTIVE

To measure the views of general practitioners (GPs) and rheumatologists in a nationwide evaluation, so as to optimise their cooperation in managing patients with inflammatory rheumatic diseases.

METHODS

A questionnaire covering aspects of collaboration was sent, both by mail and/or by email, to all GPs and rheumatologists in Austria. Topics covered were (i) examinations and interventions to be performed before referral, (ii) the spectrum of diseases to be referred, and (iii) the role of GPs in follow-up and continuous management of patients.

RESULTS

1,229 GPs of the 4,016 GPs (31%) and 110 of the 180 rheumatologists (61%) responded to the questionnaire. In cases of suspected arthritis, 99% of the GPs and 92% of the rheumatologists recommended specific laboratory tests, and 92% and 70%, respectively, recommended X-rays of affected joints before referral. Rheumatoid arthritis and spondyloarthritis, psoriatic arthritis and connective tissue disease were unanimously seen as indications for referral to a rheumatologist. Only 12% of rheumatologists felt responsible for the treatment of hand osteoarthritis and fibromyalgia. 80% of GPs and 85% of rheumatologists were of the opinion that treatment with disease-modifying drugs should be initiated by a specialist. Subsequent drug prescription and administration by GPs was supported by a majority of GPs and rheumatologists, with a concomitant rheumatologist follow-up every three to six months.

CONCLUSION

The considerable consensus between the two professional groups constitutes a solid base for future joint recommendations, with the aim to accelerate the diagnostic process and the initiation of adequate therapy.

The role of ultrasonography in assessing disease activity in patients with rheumatoid arthritis and associated fibromyalgia

AIM

The purpose of this study is to compare and correlate US evaluation with clinical scores of the disease activity in patients with rheumatoid arthritis (RA) and concomitant fibromyalgia (FM).

MATERIAL AND METHODS

Ten patients diagnosed with RA according to the 2010 ACR/EULAR classification criteria and associated FM based on the ACR 1990 classification criteria and two control groups, one with RA (10 patients) and one with FM (10 patients), were included. Clinical assessment was performed and the disease activity scores were calculated. Synovial/tenosynovial hypertrophy, fluid collections in grey scale (GS), and Power Doppler (PD) US assessed by US in the 28 joints included in the disease activity score 28 (DAS28).

RESULTS

GS US score and PD US scores were correlated with DAS28 only in patients with RA (Pearson r coefficients 0.3 and 0.5). Mean DAS28 score was significantly higher in the RA/FM group, compared to RA and FM (5.6 versus 4.6 versus 4.5, respectively). Patients with RA/FM had similar median US scores to RA patients, while in FM group significantly lower median US scores were detected (16 versus 9.5 versus 0 for GS US and 3.5 versus 1.5 versus 0 for PD US, respectively).

CONCLUSIONS

Disease activity scores should be interpreted with caution in patients with RA and FM. When available, US should be used to guide treatment decisions in patients with RA and FM.

[Body composition by dual-energy x-ray absorptiometry in women with fibromyalgia]

OBJECTIVES

To assess body composition in women with fibromyalgia (FM) comparing to the reference value for healthy women.

PATIENTS AND METHODS

Cross-sectional observational analytical study, with 52 women selected with Fibromyalgia, according American College of Rheumatology (ACR, 1990) criteria. The patients were selected in Hospital de Clínicas da Universidade Federal do Paraná (HC-UFPR) and divided into two groups, 28 patients with a BMI (Body Mass Index) equal or higher (≥) than 25kg/m2 and 24 patients with BMI less or equal (≤) 24.99 kg/m2, subjected to physical examination for the count of tender points (TP) and completing the fibromyalgia impact questionnaire (FIQ). The assessment of body composition was performed by the Dual-Energy X-Ray Absorptiometry (DXA). The values of the fat mass percentage (MG %) found in the two groups were compared to the average percentage of MG by age and sex, described by Heward (2004).

RESULTS

The mean age of the study groups was 47.8 ± 8.6 years, the FIQ score was 70.5 ± 18.6 and TP 16.2 ± 2.0. The mean BMI was 26.4 ± 4.1 kg/m2, and the amount of MG was 25.2 ± 7.8 kg and 39.5 ± 6.8%, and lean mass (LM) was 37 2 ± 3.7 kg and 60.4 ± 7.3%. In the group with BMI ≤ 25 kg/m2, the MG % was 33.8% (21.5 -42.4) and in the group with BMI ≥ 25 kg/m2 of the MG was 44.4% (37.6 -56.2).

CONCLUSION

Both groups women with FM eutrophic as the overweight and obese group, presented higher reference MG% levels comparing with the standard levels for healthy women.

Sono-myography and sono-myoelastography of the tender points of women with fibromyalgia

Sono-myography and sono-myoelastography have been found useful in the investigation of myofascial trigger points. The objective of this study was to use the same techniques to investigate the morphology, stiffness and blood flow of tender points in women with fibromyalgia and to compare the results with those for samples from healthy patients. Algometry tests indicated significant differences between groups (p < 0.001). Elliptical and hypoechoic areas were observed in the ultrasound images of the upper trapezius in both groups. No differences between groups were found in the number of hypoechoic areas (p = 0.167, t = 1.008); blood flow also did not differ between the groups. Larger hypoechoic areas were found in the fibromyalgia group (p = 0.139, t = 1.317). Sono-myoelastography did not reveal greater stiffness in these areas compared with the rest of the muscle. These results lead us to believe that sono-myoelastography and sono-myography, used in the diagnosis of myofascial trigger points, may not be able to discriminate tender points.

Sensitivity and specificity of ultrasonography and low-field magnetic resonance imaging for diagnosing arthritis

OBJECTIVES

To evaluate the value of grey-scale ultrasonography (US) including power Doppler ultrasonography (PDUS) and low-field magnetic resonance imaging (MRI) for the diagnosis of arthritis in a diagnostic phase III study.

METHODS

Fifty consecutive patients with suspected arthritis were included in the study. Following a standardised protocol, US of the carpus and the metacarpophalangeal (MCP) joints of the dominant hand was performed. Subsequently, low-field MRI was done using standard sequences, with contrast agent (Gadolinium DTPA) administered to 29 patients.

RESULTS

In 32 out of 50 patients a clinical diagnosis of arthritis was established. In grey-scale ultrasonography including PDUS, sensitivity and specificity were determined as 0.94 and 0.5, respectively, for synovitis (effusion and hypertrophy), 0.72 and 0.94, respectively, for Doppler signals, and 0.38 and 1.0, respectively, for bone erosions. In low-field MRI, sensitivity and specificity values were 0.77 and 0.75, respectively, for synovitis (when using contrast agent), 0.48 and 0.78, respectively, for bone marrow oedema, and 0.58 and 0.83, respectively, for bone erosion.

CONCLUSIONS

Both grey-scale ultrasonography including PDUS and low-field MRI are suitable imaging methods for diagnosing arthritis at an early stage. However, PDUS displays a higher specificity and almost the same sensitivity as compared to contrast-enhanced MRI, while being a much simpler and less costly procedure.

Entheseal power Doppler ultrasonography: a comparison of psoriatic arthritis and fibromyalgia

OBJECTIVE

To compare the power Doppler ultrasonography (PDUS) pictures of peripheral entheses in patients with psoriatic arthritis (PsA) and fibromyalgia (FM).

METHODS

Thirty patients with PsA and 30 with FM participating in a study aimed at identifying the clinical features that distinguish the 2 conditions underwent the PDUS assessment of 14 major peripheral entheses. All of the detected entheseal changes were recorded and scored, and the data were statistically analyzed by means of univariate analysis and receiver-operating characteristic curves.

RESULTS

Four hundred twenty entheseal sites were assessed in each group of patients. At least 1 lesion was detected in each of the patients with PsA and in 80% of the patients with FM (p = 0.01), but inflammatory changes were present in respectively 70% and 23% (p = 0.001). A cutoff point of ≥ 3 involved sites had the greatest discriminating power in the patients with PsA, who were the only patients with bony erosions. PDUS signs of plantar fascia enthesopathy and Achilles tendon inflammation were highly specific of PsA.

CONCLUSION

PDUS assessment of the peripheral entheses distinguishes patients with PsA and patients with FM in terms of the number and distribution of the involved sites, and the presence of inflammatory changes.

Ultrasound imaging for the rheumatologist XXXIX. Sonographic assessment of the hip in fibromyalgia patients

Fibromyalgia syndrome (FMS) is a common form of non-inflammatory rheumatism within the general population with symptoms often mimicking those of arthritis or muscle disorders. Arthralgic symptoms in the region of the hip are commonly mentioned by patients with FMS and one of the diagnostic trigger points for the condition is found around the greater trochanter. To date, no formal imaging studies using ultrasound (US) have been performed in FMS. This study describes the correlation between clinical and US findings in patients presenting with primary FMS to rheumatology clinics. In the majority of the patients, no significant pathological US abnormalities were detected.

Decreased muscle blood flow in fibromyalgia patients during standardised muscle exercise: A contrast media enhanced colour doppler study

The aim of the study was to investigate if contrast enhanced ultrasound (US) imaging of muscular blood flow during and following exercise could detect alterations in vascularity in fibromyalgia (FM) patients. Ten FM patients and 10 matched controls were examined with US during standardised static and directly following static and dynamic muscular contractions of the infraspinatus muscle. Doppler ultrasound evaluation was performed before and after the administration of ultrasound contrast media. The FM patients had lower magnitude of muscle vascularity following dynamic (p<0.001) and during (p<0.002) static exercise compared to controls. The immediate flow response to muscular activity was not only of a lower magnitude, but also of a shorter duration in FM patients following dynamic exercise (p<0.001) and during static exercise (p<0.01). There were no statistically significant group differences in blood flow intensity or duration following static contraction. In conclusion, contrast enhanced US was found useful to study real-time muscle blood flow changes during and following standardised, low-intensity exercise in FM patients and healthy controls. Our results support the suggestion that muscle ischemia can contribute to pain in FM, possibly by maintaining the central nervous changes such as central sensitisation/disinhibition. US with contrast can be a new valuable approach to assess muscle perfusion in pain patients during standardised exercise.