Peter Stanwell

The prevalence of food addiction as assessed by the Yale Food Addiction Scale: a systematic review.

Obesity is a global issue and it has been suggested that an addiction to certain foods could be a factor contributing to overeating and subsequent obesity. Only one tool, the Yale Food Addiction Scale (YFAS) has been developed to specifically assess food addiction. This review aimed to determine the prevalence of food addiction diagnosis and symptom scores, as assessed by the YFAS. Published studies to July 2014 were included if they reported the YFAS diagnosis or symptom score and were published in the English language. Twenty-five studies were identified including a total of 196,211 predominantly female, overweight/obese participants (60%). Using meta-analysis, the weighted mean prevalence of YFAS food addiction diagnosis was 19.9%. Food addiction (FA) diagnosis was found to be higher in adults aged >35 years, females, and overweight/obese participants. Additionally, YFAS diagnosis and symptom score was higher in clinical samples compared to non-clinical counterparts. YFAS outcomes were related to a range of other eating behavior measures and anthropometrics. Further research is required to explore YFAS outcomes across a broader spectrum of ages, other types of eating disorders and in conjunction with weight loss interventions to confirm the efficacy of the tool to assess for the presence of FA.

Diffusion-weighted Imaging of the Breast: Principles and Clinical Applications

Diffusion-weighted imaging provides a novel contrast mechanism in magnetic resonance (MR) imaging and has a high sensitivity in the detection of changes in the local biologic environment. A significant advantage of diffusion-weighted MR imaging over conventional contrast material-enhanced MR imaging is its high sensitivity to change in the microscopic cellular environment without the need for intravenous contrast material injection. Approaches to the assessment of diffusion-weighted breast imaging findings include assessment of these data alone and interpretation of the data in conjunction with T2-weighted imaging findings. In addition, the analysis of apparent diffusion coefficient (ADC) value can be undertaken either in isolation or in combination with diffusion-weighted and T2-weighted imaging. Most previous studies have evaluated ADC value alone; however, overlap in the ADC values of malignant and benign disease has been observed. This overlap may be partly due to selection of b value, which can influence the concomitant effect of perfusion and emphasize the contribution of multicomponent model influences. The simultaneous assessment of diffusion-weighted and T2-weighted imaging data and ADC value has the potential to improve specificity. In addition, the use of diffusion-weighted imaging in a standard breast MR imaging protocol may heighten sensitivity and thereby improve diagnostic accuracy. Standardization of diffusion-weighted imaging parameters is needed to allow comparison of multicenter studies and assessment of the clinical utility of diffusion-weighted imaging and ADC values in breast evaluation.

How Accurate is Web-Based Self-Reported Height, Weight, and Body Mass Index in Young Adults?

Background Web-based approaches are an effective and convenient medium to deliver eHealth interventions. However, few studies have attempted to evaluate the accuracy of online self-reported weight, and only one has assessed the accuracy of online self-reported height and body mass index (BMI). Objective This study aimed to validate online self-reported height, weight, and calculated BMI against objectively measured data in young Australian adults. Methods Participants aged 18-35 years were recruited via advertisements on social media sites and reported their current height and weight as part of an online survey. They then subsequently had the same measures objectively assessed by a trained researcher. Results Self-reported height was significantly overestimated by a mean of 1.36 cm (SD 1.93; P<.001), while self-reported weight was significantly underestimated by –0.55 kg (SD 2.03; P<.001). Calculated BMI was also underestimated by –0.56 kg/m2 (SD 0.08; P<.001). The discrepancy in reporting resulted in the misclassification of the BMI category of three participants. Measured and self-reported data were strongly positively correlated (height: r=.98, weight: r=.99, BMI: r=.99; P<.001). When accuracy was evaluated by BMI category and gender, weight remained significantly underreported by females (P=.002) and overweight/obese participants (P=.02). Conclusions There was moderate to high agreement between self-reported and measured anthropometric data. Findings suggest that online self-reported height and weight can be a valid method of collecting anthropometric data.

Neurospectroscopy: The Past, Present and Future

Neurospectroscopy with respect to its past, present and future has been reported. It is helpful to understand the biochemical relevance of each of the major resonances in the brain spectra. Lactate is seen in the spectrum as a doublet at 1.33 ppm. Healthy tissues do not have sufficient lactate to be detectable by MRS. Neurospectroscopy provides information on brain constituents. Pattern recognition blends pattern recognition techniques and multivariate statistical analysis with solid, comprehensive software engineering practices. Neurospectroscopy offers a window into the chemistry of the human brain, reporting on normal mechanisms as well as the changes that occur with degeneration, disease, pain, cancer, and infection. Alzheimers disease can now be identified much earlier than before offering earlier management before the disease progresses. The long-term effect of shaken baby syndrome and traumatic brain injury can be gauged by neurospectroscopy.

Neural Responses to Visual Food Cues According to Weight Status: A Systematic Review of Functional Magnetic Resonance Imaging Studies

Emerging evidence from recent neuroimaging studies suggests that specific food-related behaviors contribute to the development of obesity. The aim of this review was to report the neural responses to visual food cues, as assessed by functional magnetic resonance imaging (fMRI), in humans of differing weight status. Published studies to 2014 were retrieved and included if they used visual food cues, studied humans >18 years old, reported weight status, and included fMRI outcomes. Sixty studies were identified that investigated the neural responses of healthy weight participants (n = 26), healthy weight compared to obese participants (n = 17), and weight-loss interventions (n = 12). High-calorie food images were used in the majority of studies (n = 36), however, image selection justification was only provided in 19 studies. Obese individuals had increased activation of reward-related brain areas including the insula and orbitofrontal cortex in response to visual food cues compared to healthy weight individuals, and this was particularly evident in response to energy dense cues. Additionally, obese individuals were more responsive to food images when satiated. Meta-analysis of changes in neural activation post-weight loss revealed small areas of convergence across studies in brain areas related to emotion, memory, and learning, including the cingulate gyrus, lentiform nucleus, and precuneus. Differential activation patterns to visual food cues were observed between obese, healthy weight, and weight-loss populations. Future studies require standardization of nutrition variables and fMRI outcomes to enable more direct comparisons between studies.

A Systematic Review of Proton Magnetic Resonance Spectroscopy Findings in Sport-Related Concussion

Traditional structural neuroimaging techniques are normal in athletes who sustain sport-related concussions and are only considered to be clinically helpful in ruling out a more serious brain injury. There is a clinical need for more sophisticated, non-invasive imaging techniques capable of detecting changes in neurophysiology after injury. Concussion is associated with neurometabolic changes including neuronal depolarization, release of excitatory neurotransmitters, ionic shifts, changes in glucose metabolism, altered cerebral blood flow, and impaired axonal function. Proton magnetic resonance spectroscopy ((1)H-MRS, or simply MRS) is capable of measuring brain biochemistry and has the potential to identify and quantify physiologic changes after concussion. The focus of the current review is to provide an overview of research findings using MRS in sport-related concussion. A systematic review of articles published in the English language, up to February 2013, was conducted. Articles were retrieved via the databases: PsychINFO, Medline, Embase, SportDiscus, Scopus, Web of Science, and Informit using key terms: magnetic resonance spectroscopy, nuclear magnetic resonance spectroscopy, neurospectroscopy, spectroscopy, two-dimensional nuclear magnetic resonance spectroscopy, correlation spectroscopy, J-spectroscopy, exchange spectroscopy, nuclear overhauser effect spectroscopy, NMR, MRS, COSY, EXSY, NOESY, 2D NMR, craniocerebral trauma, mild traumatic brain injury, mTBI, traumatic brain injury, brain concussion, concussion, brain damage, sport, athletic, and athlete. Observational, cohort, correlational, cross-sectional, and longitudinal studies were all included in the current review. The review identified 11 publications that met criteria for inclusion, comprised of data on 200 athletes and 116 controls. Nine of 11 studies reported a MRS abnormality consistent with an alteration in neurochemistry. The results support the use of MRS as a research tool for identifying altered neurophysiology and monitoring recovery in adult athletes, even beyond the resolution of post-concussive symptoms and other investigation techniques returning to normative levels. Larger cross-sectional, prospective, and longitudinal studies are needed to understand the sensitivity and prognostic value of MRS within the field of sport-related concussion.

In vivo proton MR spectroscopy of the breast.

In vivo proton magnetic resonance (MR) spectroscopy (hydrogen 1 spectroscopy) provides useful information about the pathology of breast lesions by the measurement of diagnostic chemicals visible on the MR timescale. Spectroscopic measurements may be obtained following contrast-enhanced MR imaging by applying a point-resolved spatially localized spectroscopy sequence. The observation of resonances at discrete spectral frequencies allows an accurate diagnosis. In spectra obtained in vivo in malignant breast cancers, an observed resonance at 3.23 ppm is consistent with phosphocholine. In spectra from benign breast lesions and some normal breast tissue in lactating mothers and in some nonlactating healthy women, a recorded resonance at 3.28 ppm is thought to originate from glycerophosphocholine, taurine, or myoinositol. The success of in vivo spectroscopy depends on the appropriate pre-acquisition setup, acquisition protocol, and postprocessing techniques for achieving high spectral resolution and a signal-to-noise ratio sufficient to separate the resonances of the important biomarkers. When implemented correctly, the method is diagnostically accurate and robust.

Glutamate and glutamine: a review of in vivo MRS in the human brain

Our understanding of the roles that the amino acids glutamate (Glu) and glutamine (Gln) play in the mammalian central nervous system has increased rapidly in recent times. Many conditions are known to exhibit a disturbance in Glu–Gln equilibrium, and the exact relationships between these changed conditions and these amino acids are not fully understood. This has led to increased interest in Glu/Gln quantitation in the human brain in an array of conditions (e.g. mental illness, tumor, neuro‐degeneration) as well as in normal brain function.

Glycosaminoglycan content of knee cartilage following posterior cruciate ligament rupture demonstrated by delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC). A case report.

Following joint trauma and during the early stages of cartilage degeneration, typical changes become apparent in tissue structure and composition, including the loss of glycosaminoglycan1,2. These changes often are not apparent on conventional magnetic resonance imaging or visible at arthroscopy, thereby precluding diagnosis. Delayed gadolinium-enhanced magnetic resonance imaging of cartilage, or dGEMRIC, is an emerging in vivo method for the assessment of the biochemical composition of articular cartilage and provides a surrogate measure of glycosaminoglycan content3,4. When injected intravenously, the anionic contrast agent gadolinium diethylene triamine penta-acetic acid (Gd-DTPA2–) penetrates cartilage both from the synovial surface and from the subchondral bone3,5. Given sufficient time, the anionic contrast agent distributes inversely to the fixed negative charge associated with the cartilage glycosaminoglycan content in accordance with the Donnan principle of equilibrium. Gd-DTPA2-therefore distributes in relatively higher concentrations in regions of low glycosaminoglycan, and vice versa. Gd-DTPA2-has a concentration-dependent effect on the magnetic resonance imaging parameter T1; therefore, T1 imaging in the presence of Gd-DTPA2– (T1Gd) reflects the cartilage Gd-DTPA2–concentration and, hence, glycosaminoglycan concentration. We present the case of a patient (one of the authors [A.A.Y.]) who sustained an injury to the posterior cruciate ligament of the knee while enrolled as a “normal” control subject in a dGEMRIC study of the knee. This incidental occurrence provided us with a unique opportunity to visualize the temporal and spatial changes that occur in cartilage biochemistry following an acute posterior cruciate ligament rupture. Athirty-year-old man (one of the authors [A.A.Y.]) was involved in a motor-vehicle accident in which he sustained a direct blow to the anterior aspect of the proximal portion of the right tibia at 90° of knee flexion (a typical “dashboard” type of …

Proton MRS of the breast in the clinical setting.

Information for determining whether a primary breast lesion is invasive and its receptor status and grade can be obtained before surgery by performing proton MRS on a fine‐needle aspiration biopsy (FNAB) specimen and analyzing the MRS information by a pattern recognition method. Two‐dimensional MRS, on either specimens or cells, allows the unambiguous assignment of most resonances. When correlated with the spectral regions selected by the pattern recognition method, there are strong indications for the biochemical markers responsible for prognostic information of invasive capacity and metastatic spread. Spectral assignments and biological correlations can be made using cell models. In vivo MRS can distinguish invasive from benign lesions. This pathological distinction can be made from the presence of resonances at discrete frequencies. To achieve this level of spectral resolution and signal‐to‐noise ratio, there are stringent requirements when acquiring and processing the data. The challenge now is to implement two‐dimensional MRS in vivo. Until this is realized, the combination of in vivo MR, for diagnosis and spatial location, and MRS, for image‐guided biopsy to provide information on tumor spread, promises to provide a higher level of preoperative diagnosis than previously achieved. Copyright