PUBLICATIONS

2015

Mittra E, Marx E, Biswal S, Mackey S. Utility of FDG PET/CT in patients with Myofascial Pain Syndrome. J. Nucl. Med. 2015;56(supplement 3):1694-1694.
1694Objectives The mechanism of uptake of 18F-FDG suggests a role in the evaluation of pain. Areas of FDG uptake in muscle are often seen in oncology PET scans but of unknown etiology. To understand this better, we examined a group of patients with significant focal muscle pain with FDG PET/CT.Methods Patients with a diagnosis of Myofascial Pain Syndrome (MPS) and active trigger points were prospectively recruited from the Stanford University Pain Management Center and scanned with a whole-body 18F-FDG PET/CT. Patients with a history of cancer, recent surgery, or recent trigger point injections were excluded. Medications that may decrease FDG uptake were temporarily stopped. The location of the patients pain were identified by a physician, as well as the by the patient, and recorded on a standard whole-body diagram. The PET/CT scans were reviewed without knowledge of the location of the patient s pain, then correlated.Results Eight subjects included 5 women and 3 men, with an average age of 49 years. The average pain score was 7.5/10. The sites of pain primarily included the neck and back. The physician and patient reported sites of pain agreed in all cases. Only 1 out of the 8 patients studied had any abnormal 18F-FDG uptake seen on their PET/CT scan; all other scans were negative, both qualitatively and qualitatively. That one patient (see figure) had abnormal focal FDG uptake in the right T9/10 intervertebral space, which correlated with the radicular distribution of his pain along the right mid-back. Ultimately, an osteid osteoma was removed from this site with subsequent pain resolution.Conclusions Our hypothesis that FDG would show focal areas of muscle activity in patients with MPS was not borne out. These results suggest that increased glucose utilization is either not associated with muscle pain, or the degree of uptake is below the sensitivity for PET. As such, this study does not support the use of FDG PET for MPS. Other types of painful conditions may have different findings and should be studied.
Sturgeon JA, Tieu MM, Jastrzab LE, McCue R, Gandhi V, Mackey SC. Nonlinear Effects of Noxious Thermal Stimulation and Working Memory Demands on Subjective Pain Perception. Pain Med. 2015;16(7):1301-1310.
OBJECTIVE: A bidirectional relationship between working memory (WM) and acute pain has long been assumed, but equivocal evidence exists regarding this relationship. This study characterized the relationship between WM and acute pain processing in healthy individuals using an adapted Sternberg WM task. DESIGN: Participants completed a Sternberg task while receiving noxious thermal stimulation. Participants received a pseudorandom presentation of four different temperatures (baseline temperatures and individually determined low-, medium-, and high-temperature stimuli) and four levels of Sternberg task difficulty (0-, 3-, 6-, and 9-letter strings). SUBJECTS: Twenty-eight healthy participants were recruited from Stanford University and the surrounding community to complete this study. RESULTS: A nonlinear interaction between intensity of thermal stimulation and difficulty of the Sternberg task was noted. Increased cognitive load from the Sternberg task resulted in increased perception of pain in low-intensity thermal stimulation but suppressed pain perception in high-intensity thermal stimulation. Thermal stimulation had no significant effect on participants response time or accuracy on the Sternberg task regardless of intensity level. CONCLUSIONS: Pain perception appears to decrease as a function of WM load only for sufficiently noxious stimuli. However, increasing noxious stimuli did not affect cognitive performance. These complex relationships may reflect a shared cognitive space that can become “overloaded” with input of multiple stimuli of sufficient intensity.
Sutcliffe S, Bradley CS, Clemens JQ, et al. Urological chronic pelvic pain syndrome flares and their impact: qualitative analysis in the MAPP network. Int. Urogynecol. J. 2015;26(7):1047-1060.
INTRODUCTION AND HYPOTHESIS: Although in-depth qualitative information is critical to understanding patients symptom experiences and to developing patient-centered outcome measures, only one previous qualitative study has assessed urological chronic pelvic pain syndrome (UCPPS) symptom exacerbations (“flares”). METHODS: We conducted eight focus groups of female UCPPS (interstitial cystitis/bladder pain syndrome) patients at four sites from the MAPP Research Network (n = 57, mean = 7/group) to explore the full spectrum of flares and their impact on patients lives. RESULTS: Flare experiences were common and varied widely in terms of UCPPS symptoms involved, concurrent nonpelvic symptoms (e.g., diarrhea), symptom intensity (mild to severe), duration (minutes to years), and frequency (daily to \textless once/year), although the most commonly described flares were painful flares lasting days. These latter flares were also most disruptive to participants lives, causing some to cancel social events, miss work or school, and in the worst cases, go to the emergency room or on disability leave. Participants also reported a longer-term impact of flares, including negative effects on their sexual functioning and marital, family, and social relationships; and the loss of employment or limited career or educational advancement. Emerging themes included the need for a sense of control over unpredictable symptoms and reduced social engagement. CONCLUSIONS: Given their negative impact, future research should focus on approaches to prevent flares, and to reduce their frequency, severity, and/or duration. Patients quality of life may also be improved by providing them with a sense of control over their symptoms through ready access to flare medications/therapy, and by engaging them socially.
PURPOSE: Several chronic pain conditions may be distinguished by condition specific brain anatomical and functional abnormalities on imaging, which are suggestive of underlying disease processes. We present what is to our knowledge the first characterization of interstitial cystitis/bladder pain syndrome associated white matter (axonal) abnormalities based on multicenter neuroimaging from the MAPP Research Network. MATERIALS AND METHODS: We assessed 34 women with interstitial cystitis/bladder pain syndrome and 32 healthy controls using questionnaires on pain, mood and daily function. White matter microstructure was evaluated by diffusion tensor imaging to model directional water flow along axons or fractional anisotropy. Regions correlating with clinical parameters were further examined for gender and syndrome dependence. RESULTS: Women with interstitial cystitis/bladder pain syndrome showed numerous white matter abnormalities that correlated with pain severity, urinary symptoms and impaired quality of life. Interstitial cystitis/bladder pain syndrome was characterized by decreased fractional anisotropy in aspects of the right anterior thalamic radiation, the left forceps major and the right longitudinal fasciculus. Increased fractional anisotropy was detected in the right superior and bilateral inferior longitudinal fasciculi. CONCLUSIONS: To our knowledge we report the first characterization of brain white matter abnormalities in women with interstitial cystitis/bladder pain syndrome. Regional decreases and increases in white matter integrity across multiple axonal tracts were associated with symptom severity. Given that white matter abnormalities closely correlated with hallmark symptoms of interstitial cystitis/bladder pain syndrome, including bladder pain and urinary symptoms, brain anatomical alterations suggest that there are neuropathological contributions to chronic urological pelvic pain.
The 2011 Institute of Medicine report Relieving Pain in America estimates that 100 million adult Americans are affected by chronic pain, costing a staggering \$560 billion to \$635 billion annually. In the context of this immense personal and socioeconomic burden, it is essential that all stakeholders, including providers, patients, third-party payers, and policy makers, understand the necessities of appropriate, accurate assessment and treatment of patients with chronic pain. This review examines the psychosocial consequences of pain and existing disparities in treatment. Particular emphasis is given to the challenge of using prescription opioids in the treatment of chronic noncancer pain, given the ongoing epidemic of deaths from prescription opioid overdose. Strategies for initial risk assessment and ongoing monitoring are discussed for detecting opioid misuse, abuse, and addiction. In addition, the challenges of treating patients with comorbid pain and substance use disorder are reviewed, and the role of the addiction specialist is highlighted. The biopsychosocial model of pain is reviewed as a framework for the interdisciplinary, multimodal approach to pain management, which is often necessary to treat patients with complex chronic pain conditions and comorbid psychiatric diagnoses. An interdisciplinary team consisting of pain specialists, mental health providers, physical/occupational therapists, nurses, and primary care providers is necessary not only for ongoing assessment of multiple relevant outcomes but also for overseeing the delivery of multimodal treatments (e.g., medications, interventions, physical/occupational therapy, and psychosocial education). To move toward personalized treatment of patients with pain, future needs in research, clinical care, and education are discussed.
PURPOSE: We used MAPP data to identify participants with urological chronic pelvic pain syndromes only or a chronic functional nonurological associated somatic syndrome in addition to urological chronic pelvic pain syndromes. We characterized these 2 subgroups and explored them using 3 criteria, including 1) MAPP eligibility criteria, 2) self-reported medical history or 3) RICE criteria. MATERIALS AND METHODS: Self-reported cross-sectional data were collected on men and women with urological chronic pelvic pain syndromes, including predominant symptoms, symptom duration and severity, nonurological associated somatic syndrome symptoms and psychosocial factors. RESULTS: Of 424 participants with urological chronic pelvic pain syndromes 162 (38%) had a nonurological associated somatic syndrome, including irritable bowel syndrome in 93 (22%), fibromyalgia in 15 (4%), chronic fatigue syndrome in 13 (3%) and multiple syndromes in 41 (10%). Of 233 females 103 (44%) had a nonurological associated somatic syndrome compared to 59 of 191 males (31%) (p = 0.006). Participants with a nonurological associated somatic syndrome had more severe urological symptoms and more frequent depression and anxiety. Of 424 participants 228 (54%) met RICE criteria. Of 228 RICE positive participants 108 (47%) had a nonurological associated somatic syndrome compared to 54 of 203 RICE negative patients (28%) with a nonurological associated somatic syndrome (p \textless 0.001). CONCLUSIONS: Nonurological associated somatic syndromes represent important clinical characteristics of urological chronic pelvic pain syndromes. Participants with a nonurological associated somatic syndrome have more severe symptoms, longer duration and higher rates of depression and anxiety. RICE positive patients are more likely to have a nonurological associated somatic syndrome and more severe symptoms. Because nonurological associated somatic syndromes are more common in women, future studies must account for this potential confounding factor in urological chronic pelvic pain syndromes.
Deyo RA, Dworkin SF, Amtmann D, et al. Report of the NIH Task Force on research standards for chronic low back pain. Phys. Ther. 2015;95(2):e1—e18.
Note fr 5ym PTJ s Editor in Chief: Both investigators and readers get frustrated reading research on low back pain because of different definitions of “chronic” and different outcome measures. Lack of consensus on study methods makes it difficult to determine if …
Brain network activity associated with altered motor control in individuals with chronic pain is not well understood. Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS) is a debilitating condition in which previous studies have revealed altered resting pelvic floor muscle activity in men with CP/CPPS compared to healthy controls. We hypothesized that the brain networks controlling pelvic floor muscles would also show altered resting state function in men with CP/CPPS. Here we describe the results of the first test of this hypothesis focusing on the motor cortical regions, termed pelvic-motor, that can directly activate pelvic floor muscles. A group of men with CP/CPPS (N = 28), as well as group of age-matched healthy male controls (N = 27), had resting state functional magnetic resonance imaging scans as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network study. Brain maps of the functional connectivity of pelvic-motor were compared between groups. A significant group difference was observed in the functional connectivity between pelvic-motor and the right posterior insula. The effect size of this group difference was among the largest effect sizes in functional connectivity between all pairs of 165 anatomically-defined subregions of the brain. Interestingly, many of the atlas region pairs with large effect sizes also involved other subregions of the insular cortices. We conclude that functional connectivity between motor cortex and the posterior insula may be among the most important markers of altered brain function in men with CP/CPPS, and may represent changes in the integration of viscerosensory and motor processing.