Utility of shape evolution and displacement in the classification of chronic multiple sclerosis lesions.

The accurate recognition of multiple sclerosis (MS) lesions is challenged by the high sensitivity and imperfect specificity of MRI. To examine whether longitudinal changes in volume, surface area, 3-dimensional (3D) displacement (i.e. change in lesion position), and 3D deformation (i.e. change in lesion shape) could inform on the origin of supratentorial brain lesions, we prospectively enrolled 23 patients with MS and 11 patients with small vessel disease (SVD) and performed standardized 3-T 3D brain MRI studies. Bayesian linear mixed effects regression models were constructed to evaluate associations between changes in lesion morphology and disease state. A total of 248 MS and 157 SVD lesions were studied. Individual MS lesions demonstrated significant decreases in volume < 3.75mm3 (p = 0.04), greater shifts in 3D displacement by 23.4% with increasing duration between MRI time points (p = 0.007), and greater transitions to a more non-spherical shape (p < 0.0001). If 62.2% of lesions within a given MRI study had a calculated theoretical radius > 2.49 based on deviation from a perfect 3D sphere, a 92.7% in-sample and 91.2% out-of-sample accuracy was identified for the diagnosis of MS. Longitudinal 3D shape evolution and displacement characteristics may improve lesion classification, adding to MRI techniques aimed at improving lesion specificity.

Prostate brachytherapy procedural training: incorporation of related procedures in resident training and competency assessment.

PURPOSE: Inadequate procedural training is of increasing concern in resident training, especially in prostate brachytherapy (PB). Transperineal rectal spacer placement (TRSP) requires many of the same proficiencies as PB. This work describes the assessment of teaching techniques focusing on developing critical competencies for PB using related clinical procedures (TRSP). MATERIAL AND METHODS: For PB and TRSP, key competencies were identified: 9 for PB and 7 for TRSP; 4 are shared between PB and TRSP. "Comfort level" with these procedures was assessed prior to and following participation in TRSP. RESULTS: 8 of 12 trainees at our institution participated in TRSP procedures. 2 of these trainees had prior experience with PB or related procedures and were excluded. Trainees self-reported "comfort levels" between 0 and 3 for four competency domains. Initial median comfort (MC) level for competency domains relevant to PB included: patient positioning (median 1, range 0-2), transrectal ultrasound imaging (median 1, range 0-1), fiducial placement (median 1, range 0-1), and hydrodissection (median 0, range 0-1). Median number of TRSP procedures performed by assessed trainees during the analysis period was 4 (range 1-6). Following TRSP procedure training, MC level increased: 2 points for patient positioning (median 3, range 1-3; p < 0.01), 1.5 points for transrectal ultrasound imaging (median 2.5, range 1.3, p < 0.001); 1 point for fiducial placement (median score 2, range 1-3; p < 0.001); and 1.5 points for hydrodissection (median score 2, range 1-3; p < 0.001). CONCLUSIONS: Increasing trainee involvement in related procedures to develop core competencies may help facilitate increased comfort with common skills critical to the independent performance of PB.

Anxiety mediates the effect of acute stress on working memory performance when cortisol levels are high: a moderated mediation analysis.

BACKGROUND: Anxiety is an aversive emotional state characterized by perceived uncontrollability and hypervigilance to threat that can frequently cause disruptions in higher-order cognitive processes like working memory. The attentional control theory (ACT) predicts that anxiety negatively affects the working memory system. DESIGN: This study tested the association between anxiety and working memory after the addition of stress and measured the glucocorticoid, cortisol. To better understand this relationship, we utilized a moderated mediation model. METHODS: Undergraduate students from a public university (N = 103) self-reported their anxiety levels. Participants first completed a short-term memory test. During and after a forehead cold pressor task (stress vs. control procedure) participants completed a working memory test. Salivary cortisol was taken at baseline and after the last working memory test. RESULTS: Overall, acute stress had no effect on working memory. However, we found that anxiety levels mediated the influence of condition (stressed vs. control) on working memory, but only among those individuals who had high cortisol levels after exposure to acute stress, supporting a moderated mediation model. CONCLUSIONS: These results imply that activation of the hypothalamic-pituitary-adrenal axis was necessary for working memory impairment in anxious individuals. These results provide support for the ACT.

BMI-based norms for a culturally relevant body image scale among African Americans.

The present study provides body mass index (BMI) standards for interpreting culturally relevant body image figure scores among African American men and women. Concordance between participants' and independent raters' figure selection is evaluated and the sensitivity and specificity of the figures for predicting overweight status are reported. African American adults (n = 498, 71% female) selected the figure most closely resembling them currently, and had their height and weight measured to calculate BMI. Three independent raters selected the figure that most closely resembled a subset of the participants (n = 277, 75% female). Probability that overweight status was correctly identified was 85% for participants and 98% for raters. ROC analysis showed that figures selected by raters (86%) and participants (83%) were equally sensitive in predicting overweight status using the gold standard, BMI. Figures selected by raters (98%) were more specific in predicting overweight status than when selected by participants (75%). Considerations in using participant- or rater-based norms for interpreting figure scores are discussed.