The Reliability of Two- and Three-Dimensional Cephalometric Measurements: A CBCT Study

Cephalometry is a standard diagnostic tool in orthodontic and orthognathic surgery fields. However, built-in magnification from the cephalometric machine produces double images from left- and right-side craniofacial structures on the film, which poses difficulty for accurate cephalometric tracing and measurements. The cone-beam computed tomography (CBCT) images not only allow three-dimensional (3D) analysis, but also enable the extraction of two-dimensional (2D) images without magnification. To evaluate the most reliable cephalometric analysis method, we extracted 2D lateral cephalometric images with and without magnification from twenty full-cranium CBCT datasets; images were extracted with magnification to mimic traditional lateral cephalograms. Cephalometric tracings were performed on the two types of extracted 2D lateral cephalograms and on the reconstructed 3D full cranium images by two examiners. The intra- and inter-examiner intraclass correlation coefficients (ICC) were compared between linear and angular parameters, as well as between CBCT datasets of adults and children. Our results showed that overall, tracing on 2D cephalometric images without magnification increased intra- and inter-examiner reliability, while 3D tracing reduced inter-examiner reliability. Angular parameters and children’s images had the lowest inter- and intra-examiner ICCs compared with adult samples and linear parameters. In summary, using lateral cephalograms extracted from CBCT without magnification for tracing/analysis increased reliability. Special attention is needed when analyzing young patients’ images and measuring angular parameters.

Test–Retest Reliability of the Listening Self-Efficacy Questionnaire

Purpose: The purpose of this study was to determine the test–retest reliability and the minimum detectable change (MDC) scores of the Listening Self-Efficacy Questionnaire (LSEQ). Method: A total of 77 older adults who were experienced hearing aid users were administered the LSEQ in pen–paper format on two separate occasions. They were provided the first copy of the LSEQ in the clinic to take home to complete. Those participants who completed and returned the first copy of the questionnaire were then mailed a second copy of the LSEQ to complete and return approximately 2 weeks later. The mean subscale and total scale scores from the two administrations were compared using intraclass correlation coefficients (ICCs) to determine test–retest reliability of the measure. The MDC scores, or the minimum difference between scores to demonstrate a real change in self-efficacy levels, were also calculated for each subscale and the total scale. Results: The ICCs ranged from 0.786 to 0.920 for the subscale and total scale scores. The MDC scores for the subscale and total scale ranged from 14.3% to 19.1%. Conclusions: The results of this study indicate that the LSEQ has moderate to excellent test–retest reliability. The MDC scores demonstrate that the LSEQ has the potential to detect true changes in listening self-efficacy in older patients with hearing loss who use hearing aids. The LSEQ may aid clinicians in understanding listening self-efficacy in their patients and how their self-efficacy levels change with amplification.

Validity of Domain-Specific Sedentary Time Using Accelerometer and Questionnaire with activPAL Criterion

Accelerometers based on the cut-point method are generally the most used in sedentary time (ST) research. However, mixed cut-points are an issue, so an accelerometer based on metabolic equivalents (METs) could be used as an alternative. This study aimed to validate a METs-based accelerometer (HJA-750C, OMRON) and a questionnaire that estimates domain-specific sedentary time measures using activPAL as a criterion value. We also examined whether measurement validity differed according to gender and occupation. We used data from 242 workers in the validation study. Participants wore activPAL on the thigh and OMRON on the waist for seven consecutive days with daily recording logs. The Workers Living Activity-time Questionnaire (WLAQ) was administered once. The domain-specific ST assessed quantities of ST during commuting, working time, non-working time on a workday, and non-workday. Intraclass correlation coefficients (ICC) and Spearman’s rho coefficients were then used to conduct analyses. The OMRON accelerometer showed acceptable values (r = 0.67–0.86 and ICC of 0.63–0.87) in the overall domain-specific ST. Additionally, each measurement result suggested that working time is the most accurate domain to measure ST (ICC of 0.87 for OMRON and 0.68 for WLAQ). Moreover, there were no differences in the overall validity of the results according to gender and occupation. The METs-based accelerometer has acceptable validity for ST measurements to be used among workers. Additionally, working time may be the preferred domain for the accurate assessment of ST in both objective and subjective measurements. These results can advance the quality of the sedentary research field.

Aortic Stiffness, Pulse Pressure, and Cerebral Pulsatility Progress Despite Best Medical Management: The OXVASC Cohort

Background and Purpose: Increased cerebral arterial pulsatility is associated with cerebral small vessel disease, recurrent stroke, and dementia despite the best medical treatment. However, no study has identified the rates and determinants of progression of arterial stiffness and pulsatility. Methods: In consecutive patients within 6 weeks of transient ischemic attack or nondisabling stroke (OXVASC [Oxford Vascular Study]), arterial stiffness (pulse wave velocity [PWV]) and aortic systolic, aortic diastolic, and aortic pulse pressures (aoPP) were measured by applanation tonometry (Sphygmocor), while middle cerebral artery (MCA) peak (MCA-PSV) and trough (MCA-EDV) flow velocity and Gosling pulsatility index (PI; MCA-PI) were measured by transcranial ultrasound (transcranial Doppler, DWL Doppler Box). Repeat assessments were performed at the 5-year follow-up visit after intensive medical treatment and agreement determined by intraclass correlation coefficients. Rates of progression and their determinants, stratified by age and sex, were determined by mixed-effects linear models, adjusted for age, sex, and cardiovascular risk factors. Results: In 188 surviving, eligible patients with repeat assessments after a median of 5.8 years. PWV, aoPP, and MCA-PI were highly reproducible (intraclass correlation coefficients, 0.71, 0.59, and 0.65, respectively), with progression of PWV (2.4%; P <0.0001) and aoPP (3.5%; P <0.0001) but not significantly for MCA-PI overall (0.93; P =0.22). However, PWV increased at a faster rate with increasing age (0.009 m/s per y/y; P <0.0001), while aoPP and MCA-PI increased significantly above the age of 55 years (aoPP, P <0.0001; MCA-PI, P =0.009). Higher aortic systolic blood pressure and diastolic blood pressure predicted a greater rate of progression of PWV and aoPP, but not MCA-PI, although current MCA-PI was particularly strongly associated with concurrent aoPP ( P <0.001). Conclusions: Arterial pulsatility and aortic stiffness progressed significantly after 55 years of age despite the best medical treatment. Progression of stiffness and aoPP was determined by high blood pressure, but MCA-PI predominantly reflected current aoPP. Treatments targetting cerebral pulsatility may need to principally target aortic stiffness and pulse pressure to have the potential to prevent cerebral small vessel disease.

Assessing the reproducibility of high temporal and spatial resolution dynamic contrast-enhanced magnetic resonance imaging in patients with gliomas

Temporal and spatial resolution of dynamic contrast-enhanced MR imaging (DCE-MRI) is critical to reproducibility, and the reproducibility of high-resolution (HR) DCE-MRI was evaluated. Thirty consecutive patients suspected to have brain tumors were prospectively enrolled with written informed consent. All patients underwent both HR-DCE (voxel size, 1.1 × 1.1 × 1.1 mm3; scan interval, 1.6 s) and conventional DCE (C-DCE; voxel size, 1.25 × 1.25 × 3.0 mm3; scan interval, 4.0 s) MRI. Regions of interests (ROIs) for enhancing lesions were segmented twice in each patient with glioblastoma (n = 7) to calculate DCE parameters (Ktrans, Vp, and Ve). Intraclass correlation coefficients (ICCs) of DCE parameters were obtained. In patients with gliomas (n = 25), arterial input functions (AIFs) and DCE parameters derived from T2 hyperintense lesions were obtained, and DCE parameters were compared according to WHO grades. ICCs of HR-DCE parameters were good to excellent (0.84–0.95), and ICCs of C-DCE parameters were moderate to excellent (0.66–0.96). Maximal signal intensity and wash-in slope of AIFs from HR-DCE MRI were significantly greater than those from C-DCE MRI (31.85 vs. 7.09 and 2.14 vs. 0.63; p < 0.001). Both 95th percentile Ktrans and Ve from HR-DCE and C-DCE MRI could differentiate grade 4 from grade 2 and 3 gliomas (p < 0.05). In conclusion, HR-DCE parameters generally showed better reproducibility than C-DCE parameters, and HR-DCE MRI provided better quality of AIFs.

Kinematics or Kinetics: Optimum Measurement of the Vertical Variations of the Center of Mass during Gait Initiation

Background: During gait, the braking index represents postural control, and consequently, the risk of falls. Previous studies based their determination of the braking index during the first step on kinetic methods using force platforms, which are highly variable. This study aimed to investigate whether determining the braking index with a kinematic method, through 3D motion capture, provides more precise results. Methods: Fifty participants (20 to 40 years) performed ten trials in natural and fast gait conditions. Their braking index was estimated from their first step simultaneously using a force platform and VICON motion capture system. The reliability of each braking index acquisition method was assessed by intraclass correlation coefficients, standard error measurements, and the minimal detectable change. Results: Both kinetic and kinematic methods allowed good to excellent reliability and similar minimum detectable changes (10%). Conclusion: Estimating the braking index through a kinetic or a kinematic method was highly reliable.

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

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.

Assessment of Operator Reliability in Ultrasound of the Median and Ulnar Nerve Using Bland-Altman Analysis

Currently, there is no standardized method to evaluate operator reliability in nerve ultrasound. A short prospective protocol using Bland–Altman analysis was developed to assess the level of agreement between operators with different expertise levels. A control rater without experience in nerve ultrasound, three novices after two months of training, an experienced rater with two years of experience, and a reference rater performed blinded ultrasound examinations of the left median and ulnar nerve in 42 nerve sites in healthy volunteers. The precision of Bland–Altman agreement analysis was tested using the Preiss–Fisher procedure. Intraclass correlation coefficients (ICC), coefficients of variation, and Bland–Altman limits of agreement were calculated. The sample size calculation and Preiss–Fisher procedure showed a sufficient precision of Bland–Altman agreement analysis. Limits of agreement of all trained novices ranged from 2.0 to 2.9 mm2 and were within the test’s maximum tolerated difference. Ninety-five percent confidence intervals of limits of agreement revealed a higher precision in the experienced rater’s measurements. Operator reliability in nerve ultrasound of the median and ulnar nerve arm nerves can be evaluated with a short prospective controlled protocol using Bland–Altman statistics, allowing a clear distinction between an untrained rater, trained novices after two months of training, and an experienced rater.

Ultrasonography Method of Deep Cervical Muscles and Thickness Measurement Reliability in Cervicogenic Headache and Healthy Subjects:APilot Study

Introduction: In Cervicogenic Headache (CGH), motor control of muscles is impaired and deep upper neck muscles (extensor and flexor muscles) become atrophied. In this research, thickness measurement of Longus Capitis (LCap), Rectus Capitis Posterior Major (RCPM), and Obliquus Capitis Superior (OCS) muscles were conducted and intra-rater reliability of the thickness measurement of these muscles was assessed in CGH and healthy subjects. Materials and Methods: Twenty subjects, including 10 healthy subjects (19-32 years old) and 10 CGH patients (20-35 years old) participated in this study. LCap thickness was measured at the level of C3-C4 in the supine position and posterior muscles (RCPM and OCS) thickness at the C1-C2 level in the sitting position. All ultrasound images were captured by a linear probe with a 50-mm footprint in B mode option and frequency range of 9-12 Hz. Intraclass Correlation Coefficients (ICC), Standard Error Of Measurement (SEM), and the Smallest Detectable Difference (SDD) were calculated for data analysis. Results: The ICC for thickness measurement of LCap was from 0.70 to 0.91 (good to excellent), for RCPM thickness was from 0.69 to 0.94 and for OCS muscle thickness was from 0.87 to 0.98. SEM values for LCap were between 0.08 and 0.25 and the SDD values between 0.22 and 0.71. SEM values for RCPM were between 0.22 and 0.43 and these values were reported for OCS muscle between 0.19 and 0.45. Conclusion: The results indicated that the presented position and the level of ultrasonography in this study are appropriate and ultrasound is a reliable tool to measure the deep upper neck muscle thickness in CGH and healthy subjects.