scholarly journals MR Spectroscopy of the Insula: Within- and Between-Session Reproducibility of MEGA-PRESS Measurements of GABA+ and Other Metabolites

2021 ◽  
Vol 11 (11) ◽  
pp. 1538
Author(s):  
Claire Shyu ◽  
Sonja Elsaid ◽  
Peter Truong ◽  
Sofia Chavez ◽  
Bernard Le Foll

The insula plays a critical role in many neuropsychological disorders. Research investigating its neurochemistry with magnetic resonance spectroscopy (MRS) has been limited compared with cortical regions. Here, we investigate the within-session and between-session reproducibility of metabolite measurements in the insula on a 3T scanner. We measure N-acetylaspartate + N-acetylaspartylglutamate (tNAA), creatine + phosphocreatine (tCr), glycerophosphocholine + phosphocholine (tCho), myo-inositol (Ins), glutamate + glutamine (Glx), and γ-aminobutyric acid (GABA) in one cohort using a j-edited MEGA-PRESS sequence. We measure tNAA, tCr, tCho, Ins, and Glx in another cohort with a standard short-TE PRESS sequence as a reference for the reproducibility metrics. All participants were scanned 4 times identically: 2 back-to-back scans each day, on 2 days. Preprocessing was done using LCModel and Gannet. Reproducibility was determined using Pearson’s r, intraclass-correlation coefficients (ICC), coefficients of variation (CV%), and Bland–Altman plots. A MEGA-PRESS protocol requiring averaged results over two 6:45-min scans yielded reproducible GABA measurements (CV% = 7.15%). This averaging also yielded reproducibility metrics comparable to those from PRESS for the other metabolites. Voxel placement inconsistencies did not affect reproducibility, and no sex differences were found. The data suggest that MEGA-PRESS can reliably measure standard metabolites and GABA in the insula.

2019 ◽  
Vol 90 (12) ◽  
pp. 1000-1008
Author(s):  
Caleb D. Johnson ◽  
Alice D. LaGoy ◽  
Gert-Jan Pepping ◽  
Shawn R. Eagle ◽  
Anne Z. Beethe ◽  
...  

INTRODUCTION: Designed as a more ecological measure of reaction times, the Perception-Action Coupling Task (PACT) has shown good reliability and within-subject stability. However, a lengthy testing period was required. Perceptual-motor judgments are known to be affected by proximity of the stimulus to the action boundary. The current study sought to determine the effects of action boundary proximity on PACT performance, and whether redundant levels of stimuli, eliciting similar responses, can be eliminated to shorten the PACT.METHODS: There were 9 men and 7 women who completed 4 testing sessions, consisting of 3 familiarization cycles and 6 testing cycles of the PACT. For the PACT, subjects made judgments on whether a series of balls presented on a tablet afford “posting” (can fit) through a series of apertures. There were 8 ratios of ball to aperture size (B-AR) presented, ranging from 0.2 to 1.8, with each ratio appearing 12 times (12 trials) per cycle. Reaction times and judgment accuracy were calculated, and averaged across all B-ARs. Ratios and individual trials within each B-AR were systematically eliminated. Variables were re-averaged, and intraclass correlation coefficients (ICC) and coefficients of variation (CVTE) were calculated in an iterative manner.RESULTS: With elimination of the 0.2 and 1.8 B-ARs, the PACT showed good reliability (ICC = 0.81–0.99) and consistent within-subject stability (CVTE = 2.2–14.7%). Reliability (ICC = 0.81–0.97) and stability (CVTE = 2.6–15.6%) were unaffected with elimination of up to 8 trials from each B-AR.DISCUSSION: The shortened PACT resulted in an almost 50% reduction in total familiarization/testing time required, significantly increasing usability.Johnson CD, LaGoy AD, Pepping G-J, Eagle SR, Beethe AZ, Bower JL, Alfano CA, Simpson RJ, Connaboy C. Action boundary proximity effects on perceptual-motor judgments. Aerosp Med Hum Perform. 2019; 90(12):1000–1008.


1996 ◽  
Vol 80 (1) ◽  
pp. 133-139 ◽  
Author(s):  
M. D. White ◽  
G. Bouchard ◽  
B. Buemann ◽  
N. Almeras ◽  
J. P. Despres ◽  
...  

The maintenance of weight and adipose tissue mass in humans appears to be related to a balance between the rates of oxidation and consumption of macronutrients; yet, little evidence is available on the reproducibility of 24-h macronutrient oxidation rates and how this relates to diet in the days preceding a chamber session. This study examined the reproducibility of 24-h macronutrient oxidation rates, 24-h energy expenditure (EE), and respiratory quotient (RQ) in 30 adults who ate their habitual diets before two 24-h whole body indirect calorimeter sessions. Results showed that the within-subject coefficients of variation (CVws) for 24-h EE and RQ were 2.8 and 2.6%, respectively. CVws for macronutrient oxidations ranged from approximately 15 to 25%. Means comparisons of 24-h EE, RQ, and macronutrient oxidation rates between sessions showed no significant differences, and all variables had significant positive intraclass correlation coefficients (P < 0.05). In conclusion, macronutrient oxidations all showed significant reproducibility for the group and a significant but lower reproducibility for individuals when habitual diet and activity preceded the experimental sessions.


2007 ◽  
Vol 21 (4) ◽  
pp. 474-477 ◽  
Author(s):  
Roberto Castano ◽  
Gilles Thériault ◽  
Denyse Gautrin ◽  
Heberto Ghezzo ◽  
Carole Trudeau ◽  
...  

Background To diagnose occupational rhinitis, it is mandatory to conduct an objective assessment of changes in nasal patency during specific inhalation challenge (SIC). The reproducibility of acoustic rhinometry measurements in the setting of occupational challenges has never been examined. This study assessed the reproducibility of acoustic rhinometry during SIC investigation of occupational rhinitis. Methods Twenty-four subjects underwent acoustic rhinometry measurements during SIC investigation of occupational rhinitis. Subjects attended 3–6 days of SIC within a week by means of a realistic or closed-circuit apparatus methodology Results All of the within-day intraclass correlation coefficients (ICCs) for nasal volume (2–5 cm) and minimum cross-sectional area (MCA) based on a different number of measurements (2–7) were above 0.85; all of the coefficients of variation (CVs) for the same parameters were low (below 10%). The between-day CVs based on different numbers of SIC sessions ranged from 8.0 to 8.8% and from 6.8 to 8.8% for nasal volume and MCA, respectively. The between-day ICCs ranged from 0.80 to 0.88 and from 0.83 to 0.94 for nasal volume and MCA, respectively. Conclusion Acoustic rhinometry showed good within- and between-day reproducibility and can be recommended for the objective monitoring of nasal patency during SIC investigating occupational rhinitis.


2003 ◽  
Vol 93 (5) ◽  
pp. 380-387 ◽  
Author(s):  
Hylton B. Menz ◽  
Anne Tiedemann ◽  
Marcella Mun-San Kwan ◽  
Mark Dominic Latt ◽  
Catherine Sherrington ◽  
...  

Lower-extremity problems are common in older people; however, the reliability of clinical tools used to assess foot and ankle characteristics has not been rigorously evaluated. This study evaluated the test–retest reliability of a battery of simple clinical tests of foot and ankle characteristics (tactile sensitivity of the first metatarsophalangeal joint, navicular height, foot length and width, hallux valgus severity, an overall foot problem score, ankle flexibility, ankle dorsiflexion strength, and foot pain) in 31 individuals (13 men and 18 women) aged 76 to 87 years recruited from the community. Three examiners performed the tests on two occasions approximately 2 weeks apart. Intraclass correlation coefficients and coefficients of variation were calculated for continuously scored tests, and the kappa statistic (κ) was used to determine the reliability of hallux valgus severity grading. All of the continuously scored tests had acceptable reliability (intraclass correlation coefficients of 0.64 to 0.98; coefficients of variation of 0.6% to 15.0%), as did hallux valgus severity grading (κ = 0.77; absolute percentage agreement, 84%). These simple clinical tests can now be used with confidence in clinical and research settings to provide reliable and functionally important information regarding foot and ankle characteristics in older people. (J Am Podiatr Med Assoc 93(5): 380-387, 2003)


Author(s):  
Megan Sax van der Weyden ◽  
Christopher D. Black ◽  
Daniel Larson ◽  
Brian Rollberg ◽  
Jason A. Campbell

This investigation examined relationships between a Special Weapons and Tactics-specific fitness test (SORT) and an obstacle course (OC) used for qualification in fourteen male SWAT members from three local, regional police departments. The SORT included: squat, pushup, and lunge in 60 s; pullup hold; sled drag; and Yo-Yo Intermittent Recovery Test L1. The obstacle course included: 25 m sprint (repeated); window ascent; scale under a wall; 25 m serpentine run (repeated), body drag (20 m, repeated). Pearson coefficients examined SORT and OC relationships (p ≤ 0.05); intraclass correlation coefficients (ICC2,1) assessed agreement of SORT trials. Repeated measures ANOVA evaluated differences in SORT metrics across time. Coefficients of variation (COV) examined SORT scoring consistency. The YoYo test was related to all SORT assessments (r = −0.803–0.894), except sled drag. The remaining SORT metrics were related to ≥two tests. SORT COVs ranged from 0.77–13.26% for trials 1–2 but decreased between trials 2–3 (0.95–8.97%). The OC was associated with YoYo, lunges, squats and sled drag (r = −0.790, −0.730, −0.766, and 0.802, respectively). No differences (p > 0.05) existed across SORT trials for event scores. The SORT battery appears to be a valid and reliable testing measure to assess SWAT occupational specific fitness.


2020 ◽  
Vol 33 (6) ◽  
pp. 783-791
Author(s):  
Yusuke Yokota ◽  
Tomohisa Okada ◽  
Yasutaka Fushimi ◽  
Akira Yamamoto ◽  
Satoshi Nakajima ◽  
...  

Abstract Objective To compare the absolute values and repeatability of magnetic resonance fingerprinting (MRF) with 3000 and 1500 echoes/slice acquired in 41 s and 20 s (MRF3k and MRF1.5k, respectively). Materials and methods MRF3k and MRF1.5k scans based on fast imaging with steady precession (FISP) were conducted using a 3 T scanner. Inter-scan agreement and intra-scan repeatability were investigated in 41 and 28 subjects, respectively. Region-of-interest (ROI) analysis was conducted on T1 values of MRF3k by two raters, and their agreement was evaluated using intraclass correlation coefficients (ICCs). Between MRF3k and MRF1.5k, differences in T1 and T2 values and inter-measurement correlation coefficients (CCs) were investigated. Intra-measurement repeatability was evaluated using coefficients of variation (CVs). A p value < 0.05 was considered statistically significant. Results The ICCs of ROI measurements were 0.77–0.96. Differences were observed between the two MRF scans, but the CCs of the overall ROIs were 0.99 and 0.97 for the T1 and T2 values, respectively. The mean and median CVs of repeatability were equal to or less than 1.58% and 3.13% in each of the ROIs for T1 and T2, respectively; there were some significant differences between MRF3k and MRF1.5k, but they were small, measuring less than 1%. Discussion Both MRF3k and MRF1.5k had high repeatability, and a strong to very strong correlation was observed, with a trend toward slightly higher values in MRF1.5k.


Biomechanics ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 1-14
Author(s):  
Callum Stratford ◽  
Thomas Dos’Santos ◽  
John J. McMahon

The purpose of this study was to identify whether ten repetitions and three trials were necessary to achieve stability in peak reactive strength index (RSI) during the 10/5 repeated jumps test (RJT). Twenty-five males, from multiple sports, performed three trials of the RJT on an in-ground force plate, with 90 seconds’ rest between trials. Intraclass correlation coefficients (ICC = 0.916–0.986) and coefficients of variation (CV ≤ 14.5%) were considered acceptable for all variables. Repeated-measures analysis of variance and Freidman’s tests revealed large and significant differences (p ≤ 0.006, η2 = 0.159–0.434, power ≥ 0.859) in ground contact time (GCT), jump height (JH), and subsequently RSI both between trials and repetitions. Pairwise comparisons revealed that repetitions 1–3 produced longer GCTs (p ≤ 0.05, d = 0.41–1.40), lower JHs (p ≤ 0.05, d = 0.31–0.56), and lower RSI values (p ≤ 0.05, d = 0.35–1.24). The shortest GCTs, greatest JHs and greater RSIs occurred between repetitions 7 and 10, with approximately 60% of peak RSIs occurring during these ranges. The sequential estimate technique revealed that seven repetitions were needed to attain stability in mean peak RSI. Non-significant (p = 0.554) and negligible differences (d ≤ 0.09) in the five best RSIs between trials were noted. One trial of the 10/5 RJT is sufficient to evaluate peak RSI in athletes and should reduce data collection time and fatigue.


Sports ◽  
2019 ◽  
Vol 7 (5) ◽  
pp. 125
Author(s):  
Adam M. Gonzalez ◽  
Gerald T. Mangine ◽  
Robert W. Spitz ◽  
Jamie J. Ghigiarelli ◽  
Katie M. Sell

To determine the agreement between the Open Barbell (OB) and Tendo weightlifting analyzer (TWA) for measuring barbell velocity, eleven men (19.4 ± 1.0 y) performed one set of 2–3 repetitions at four sub-maximal percentage loads, [i.e., 30, 50, 70, and 90% one-repetition maximum (1RM)] in the back (BS) and front squat (FS) exercises. During each repetition, peak and mean barbell velocity were recorded by OB and TWA devices, and the average of the 2–3 repetitions was used for analyses. Although the repeated measures analysis of variance revealed significantly (p ≤ 0.005) greater peak and mean velocity scores from OB across all intensities, high intraclass correlation coefficients (ICC2,K = 0.790–0.998), low standard error of measurement (SEM2,K = 0.040–0.119 m·s−1), and coefficients of variation (CV = 2–4%) suggested consistency between devices. Positive (r = 0.491–0.949) Pearson correlations between averages and differences (between devices) in peak velocity, as well as associated Bland-Altman plots, showed greater differences occurred as the velocity increased, particularly at low-moderate intensity loads. OB consistently provides greater barbell velocity scores compared to TWA, and the differences between devices were more apparent as the peak velocity increased with low-to-moderate loads. Strength coaches and athletes may find better agreement between devices if the mean velocity scores are only considered.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jennifer H. Therkorn ◽  
Daniella R. Toto ◽  
Michael J. Falvo

AbstractAlternative methods have been proposed to report spirometry indices from test sessions (forced expiratory volume 1 s, FEV1; forced vital capacity, FVC). However, most use the American and European Societies’ standard (ATS/ERS) which stops sessions once a repeatability threshold is met which may not accurately represent intra-session variability. Our goal was to repeat trials beyond the repeatability threshold and evaluate alternative reporting methods. 130 adults performed spirometry across two visits. Spirometry indices were reported using the ATS/ERS standard and four alternatives. 78 participants (60%) had valid data for all methods and visits. Intra-session coefficients of variation were low (FEV1: 3.1–3.7%; FVC: 2.3–2.8%). Our four alternative methods yielded FEV1 and FVC values ≤ 0.08 L different from ATS/ERS standard, which is not clinically meaningful. Intraclass correlation coefficients were ≥ 0.97 indicating consistency across repeated measures. The smallest real differences ranged from FEV1: 0.20–0.27 L and FVC: 0.18–0.24 L indicating consistency and low measurement error. Overall, all methods for reporting FEV1 and FVC demonstrated similar measurement error, precision, and stability within- and between-visits. These results suggest that once ATS/ERS repeatability is achieved, which approach is used for reporting spirometric variables may be of low clinical significance in a healthy population.


Sports ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 4
Author(s):  
Justin J. Merrigan ◽  
Jason D. Stone ◽  
W. Guy Hornsby ◽  
Joshua A. Hagen

The purpose of this study was to evaluate intrasession reliability of countermovement jump (CMJ) and isometric mid-thigh pull (IMTP) force–time characteristics, as well as relationships between CMJ and IMTP metrics. Division I sport and club athletes (n = 112) completed two maximal effort CMJ and IMTP trials, in that order, on force plates. Relative and absolute reliability were assessed using intraclass correlation coefficients (ICCs) > 0.80 and coefficients of variation (CVs) < 10%. Intrasession reliability was acceptable for the majority of the CMJ force–time metrics except for concentric rate of force development (RFD), eccentric impulse and RFD, and lower limb stiffness. The IMTP’s time to peak force, instantaneous force at 150 ms, instantaneous net force, and RFD measures were not reliable. Statistically significant weak to moderate relationships (r = 0.20–0.46) existed between allometrically scaled CMJ and IMTP metrics, with the exception of CMJ eccentric mean power not being related with IMTP performances. A majority of CMJ and IMTP metrics met acceptable reliability standards, except RFD measures which should be used with caution. Provided CMJs and IMTPs are indicative of distinct physical fitness capabilities, it is suggested to monitor athlete performance in both tests via changes in those variables that demonstrate the greatest degree of reliability.


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