Adaptive weight estimation and segmentation of beef carcass tissues from computed tomography images.

BackgroundAutomatic noninvasive oscillometric blood pressure (NIBP) devices measure mean arterial pressure (MAP); systolic and diastolic blood pressure (SBP, DBP) are algorithmically derived from MAP. The most invalid NIBP measure is SBP, yet stroke practitioners use it to manage blood pressure (BP) in accordance with thrombolysis guidelines. We determined agreement between SBP, DBP, and MAP measured manually and by NIBP in patients treated with alteplase.MethodsA multisite prospective observational study of NIBP and manual BP agreement was conducted in patients treated with alteplase immediately after bolus and infusion initiation using methods established in guidelines for the assessment of device agreement. Dual auscultatory stethoscopes were used by 2 investigators to ensure agreement with each manual BP variable and MAP was calculated using the standard formula for manual BP measures. Data were analyzed using Bland–Altman analyses and Lin concordance correlation coefficient.ResultsA total of 7 hospitals participated, collecting 5 sets of manual/NIBP BPs in 95 patients treated with alteplase (475 paired measures). Range in limits of agreement were SBP: −28.91 to 21.41 mmHg with Lin's concordance correlation coefficient 0.8; DBP: −21.0 to 19.0 mmHg with Lin's concordance correlation coefficient 0.69; and MAP: −27.5 to 16.5 mmHg with Lin's concordance correlation coefficient 0.7. There was no difference in device agreement by BP device manufacturer brand. Differences in SBP, DBP, and MAP between NIBP and manual sphygmomanometry failed to reach guideline recommendations requiring 80% of measures to fall within a 5 mmHg difference and 95% of measures to fall within a 10 mmHg difference.ConclusionNIBP devices produce significantly different BP measures then manual sphygmomanometry auscultated BP. Because NIBP devices rely on the MAP and do not directly measure SBP and DBP, definition of what constitutes safe MAP boundaries in patients treated with alteplase should be determined when automatic BP measurement is used in clinical practice.

Bone-Selective MRI as a Nonradiative Alternative to CT for Craniofacial Imaging

Placebo response complicates the interpretation of treatment response in both clinical practice and clinical trials in youth with attention-deficit/hyperactivity disorder (ADHD). In a pilot study comparing subjective ADHD symptom rating scales with scores obtained using the Quotient™ ADHD System (an objective computerized technology for assessment of hyper-activity, inattention, and impulsivity in ADHD), it was found that agreement between these 2 measures was not as strong as anticipated. This observation prompted us to evaluate placebo responses associated with subjective and objective assessments. Eligible study participants aged 6 to 14 years with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition ADHD diagnosis based on clinician interviews were randomized to 1 of 2 treatment sequence groups (placebo, low dose, and medium dose; or low dose, medium dose, and placebo) using either atomoxetine HCl or osmotic controlled-release (OROS) methylphenidate HCl as the active treatment in a 3-week, triple-blind (subject, parent, rater) trial. Subjects were exposed to placebo and different medication doses to evaluate the comparative sensitivity of objective and subjective measures in assessing changes in clinical condition. Placebo response was defined using 3 thresholds: any improvement, > 25% improvement, or > 40% improvement from baseline on Quotient™ Global Scaled Score (QGSS) or the ADHD Rating Scale (ADHD-RS) Total score from baseline to the visit when placebo was administered. Lin's concordance correlation coefficient was used to measure agreement between baseline and placebo scores for the objective and subjective assessments. Of 30 subjects with placebo and baseline scores, 80%, 47%, and 27% met the 3 response thresholds (ie, any, > 25%, or > 40% improvement, respectively) on the ADHD-RS Total score compared with 27%, 7%, and 0% on the QGSS. Lin's concordance correlation coefficient was 0.81 and 0.39 for the QGSS and the ADHD-RS Total score, respectively. Although larger trials are warranted, we tentatively conclude that using objective measures and higher response thresholds may enhance assay sensitivity in clinical trials and hence limit necessary patient enrollments to rule out type II statistical error.

To externally validate the Palacios' equation estimating the new baseline glomerular filtration rate (NB-GFR) after partial or radical-nephrectomy (PN, RN) for Renal cancer carcinoma (RCC). Our research group recently published two studies that investigated the association between renal function and cancer-specific survival in RCC. The first one included 3457 patients undergone RN or PN for a cT1-2 RCC coming from five high-volume centers; the second one considered 1767 patients undergone RN or PN for a cT1-4 RCC in a single high-volume center. From such datasets, available complete patients' data were used to calculate the predicted NB-GFR through the Palacios' equation: predicted NB-GFR = 35.03 + 0.65 ∙ preoperative GFR - 18.19 ∙ (if radical nephrectomy) - 0.25 ∙ age + 2.83 ∙ (if tumor size > 7cm) - 2.09 ∙ (if diabetes). The observed NB-GFR was calculated by the CKD-EPI equation on serum creatinine at 3-12months after surgery. Concordance between observed and predicted NB-GFR was evaluated by Lin's concordance correlation coefficient and Bland-Altman analysis. 2419 patients were included (1210, cohort #1; 1219, cohort #2). The median observed NB-GFR value in cohorts #1 and #2 was 73.0ml/min/1.73 m2 (IQR 56.1-90.1) and 64.2ml/min/1.73 m2 (IQR 49.6-83); the median predicted NB-GFR was 71.1ml/min/1.73 m2 (IQR 58-81.5) and 62.6ml/min/1.73m2 (IQR 47.9-75.9). The concordance line showed a slope of 0.80 and 0.86, and an intercept at 11.02 and 5.41ml/min/1.73 m2 in the cohort#1 and #2, respectively. The Palacio's equation moderately over-estimated and under-estimated NB-GFR, for values below and above the cut-off of 50ml/min/1.73 m2 and 35ml/min/1.73m2 in cohort#1 and #2. The Lin's concordance correlation coefficient was 0.79 (95% CI 0.77-0.81) and 0.83 (95% CI 0.82-0.85). We confirm the predictive performances of Palacios' equation, supporting its utilization in clinical practice.

Accuracy of a plastic facial cast fabricated with a custom tray in comparison with cone beam computed tomography

Multifrequency bioelectrical impedance devices such as the InBody 770 (IB770) offer faster measurements and lower costs compared with other body composition assessments. This study validated measures from IB770 against the deuterium oxide dilution technique (D2O) and DXA and compared a four-compartment (4C) model using total body water (TBW) derived from IB770 compared with D2O. A total of 55 adult females (mean ± SD, age: 21.1 ± 2.6 years) completed IB770 and DXA scans and the D2O protocol. Lin's concordance correlation coefficients (CCCs), Bland-Altman analyses, and other equivalence tests evaluated agreement between IB770 and the criterion for measures of fat mass (FM), fat-free mass (FFM), and TBW individually and as part of 4C models. There was substantial agreement between IB770 and D2O for TBW (MD = Mean Difference) (MD = 0.34 L, CCC = 0.98) and between the IB770 and DXA for FM (MD = -0.22 kg, CCC = 0.99). IB770 overestimated FFM compared with DXA (MD = 3.15 kg, CCC = 0.91). Both 4C models had almost perfect agreement for FM (CCC = 0.99), FFM (CCC = 0.99), and body fat percentage (CCC = 0.99). IB770 is valid for assessing TBW and can be used within the context of a 4C model in females.

Evaluation of Left Ventricular Volumes and Ejection Fraction from Gated Myocardial Perfusion SPECT Processed with "Myovation Evolution": Comparison of Three Automated Software Packages using Cardiac Magnetic Resonance as Reference.

Lin's concordance correlation coefficient (CCC) is a very popular scaled index of agreement used in applied statistics. To obtain a confidence interval (CI) for the estimate of CCC, jackknifing was proposed and shown to perform well in simulation as well as in applications. However, a theoretical proof of the validity of the jackknife CI for the CCC has not been presented yet. In this note, we establish a sufficient condition for using the jackknife method to construct the CI for the CCC.

Developmental/epileptic encephalopathy with spike wave activation with sleep, formerly known as electrical status epilepticus in sleep, is an electrographic pattern in which the interictal epileptiform activity is augmented by transition to sleep. Recent studies demonstrate the utility of the first 100 seconds of sleep of long-term monitoring (LTM) as a scoring method for electrical status epilepticus in sleep. Our aim was to measure the reliability of the spike-wave index (SWI) of the first 100 seconds of sleep of routine EEG (rEEG) as a tool for diagnosis of developmental/epileptic encephalopathy with spike wave activation with sleep. Approximately three hundred forty LTMs were reviewed, and 25 studies from 25 unique patients had comparable rEEGs. Two neurophysiologists calculated the SWI of the first 100 seconds of spontaneous stage II non-random eye movement sleep, the first 5-minute bin of sleep, and three separate 5-minute bins throughout sleep in LTM. This was compared to the SWI of the first 100 seconds of sleep in rEEG. Agreement was analyzed using Lin's concordance correlation coefficient (CCC). Using 50% as a diagnostic cut-off, we observed moderate agreement between the SWI of the first 100 seconds of sleep of rEEG and three bin LTM (CCC = 0.94, 95% CI: 0.88-0.97). Agreement was slightly higher for the comparison to first bin LTM SWI (CCC = 0.96, 95% CI: 0.92-0.98) and first 100 seconds LTM SWI (CCC = 0.96, 95% CI: 0.92-0.98). This study demonstrates the first 100 seconds of sleep of rEEG technique as a time efficient diagnostic tool for patients with concern for developmental/epileptic encephalopathy with spike wave activation with sleep.

Compare the impact of photon-counting detector computed tomography (PCD-CT) to conventional CT on an interstitial lung disease (ILD) quantitative machine learning (QML) model. A QML model analyzed 52 CT exams from patients who underwent same-day conventional and PCD-CT for suspected ILD. Lin's concordance correlation coefficient (CCC) assessed agreement between conventional and PCD-CT QML results. A CCC >0.90 was regarded as excellent, 0.9 to 0.8 as good, and <0.80 as a poor concordance. Spearman rank correlation evaluated the association between pulmonary function test results (PFT) and QML features (reticulation [R], honeycombing [HC], ground glass [GG], interstitial lung disease [ILD], and vessel-related structures [VRS]). Correlations were statistically significant if the 95% CI did not include 0.00 and P value <0.05. Conventional and PCD-CT QML results had good to excellent concordance (CCC ≥0.8) except for total HC (CCC <0.8), likely related to better PCD-CT honeycombing delineation. Overall, compared with conventional CT, PCD-CT had consistently more statistically significant correlation with PFT for HC (9 PCD vs. 2 conventional of 28 total and regional associations), similar correlation for R (20 PCD vs. 18 conventional of 28 associations) and VRS (19 PCD vs. 23 conventional of 28 associations), and less correlation for GG extent (12 PCD vs. 20 conventional associations). There is strong agreement between conventional and PCD-CT QML ILD features except for HC. PCD-CT improved HC but decreased GG extent correlation with PFT. Therefore, even though most quantitative features were not impacted by the newer PCD-CT technology, model adjustment is necessary.

Machine-learning modeL based on computed tomography body composition analysis for the estimation of resting energy expenditure: A pilot study.

Kidney volume is associated with renal function and the severity of renal diseases, thus accurate assessment of the kidney is important. Although the voxel count method is reported to be more accurate than several methods, its laborious and time-consuming process is considered as a main limitation. In need of a new technology that is fast and as accurate as the manual voxel count method, the aim of this study was to develop the first deep learning model for automatic kidney detection and volume estimation from computed tomography (CT) images of dogs. A total of 182,974 image slices from 386 CT scans of 211 dogs were used to develop this deep learning model. Owing to the variance of kidney size and location in dogs compared to humans, several processing methods and an architecture based on UNEt Transformers which is known to show promising results for various medical image segmentation tasks including this study. Combined loss function and data augmentation were applied to elevate the performance of the model. The Dice similarity coefficient (DSC) which shows the similarity between manual segmentation and automated segmentation by deep-learning model was 0.915 ± 0.054 (mean ± SD) with post-processing. Kidney volume agreement analysis assessing the similarity between the kidney volume estimated by manual voxel count method and the deep-learning model was r = 0.960 (p < 0.001), 0.95 from Lin's concordance correlation coefficient (CCC), and 0.975 from the intraclass correlation coefficient (ICC). Kidney volume was positively correlated with body weight (BW), and insignificantly correlated with body conditions score (BCS), age, and sex. The correlations between BW, BCS, and kidney volume were as follows: kidney volume = 3.701 × BW + 11.962 (R2 = 0.74, p < 0.001) and kidney volume = 19.823 × BW/BCS index + 10.705 (R2 = 0.72, p < 0.001). The deep learning model developed in this study is useful for the automatic estimation of kidney volume. Furthermore, a reference range established in this study for CT-based normal kidney volume considering BW and BCS can be helpful in assessment of kidney in dogs.

Significant variability exists in preoperative planning software measures of glenoid morphology for shoulder arthroplasty

To evaluate the inter-device reproducibility of retrobulbar blood flow measurements obtained by two commercially available CDI (color Doppler imaging) devices. The right eyes of 10 healthy volunteers were investigated. Four examiners, namely two ophthalmologists and two radiologists, performed CDI examination of the ophthalmic artery, central retinal artery and temporal short posterior ciliary arteries using both CDI devices: ESAOTE MYLAB™ and SIEMENS ANTARES STELLAR PLUS™. The peak systolic velocity (PSV), the end-diastolic velocity (EDV) and the resulting resistivity index (RI) were averaged for 3 cardiac cycles. To evaluate the reproducibility between both device measurements, the Lin's concordance correlation coefficient (CCC) was used. CCC can be expressed as the product of Pearson's r (the measure of precision) and C_b (the measure of accuracy). Results show that the inter-device reproducibility for CDI measurements is not acceptable since a poor degree of overall concordance (0.15<CCC<0.37) was obtained: accuracy was high (C_b>0.71) but overall precision low (0.18< Pearson's r <0.47). Ophthalmologists and radiologists obtained similar results. To evaluate the causal role of blood flow abnormalities in glaucoma, CDI analysis using different devices seems unreliable. CDI inter-device reproducibility seems unrelated to medical speciality of the examiners. However, to improve present results, the use of similar probes and standardized CDI instrument settings as well as a CDI images analysis by a single grader, might possibly improve the inter-device reproducibility when testing the retrobulbar blood flow velocity.

The aim of this study was to test reproducibility of the CT Pico method in a cadaveric model and to compare CT Pico measurements with a high-precision laser probe for optical scanning. The glenoid surface of ten dried cadaveric scapulae (with intact surface) was measured by and high-precision laser probe for optical scanning, the latter being assumed as a reference standard. Measurements were done according to the Pico technique, using a circle-shaped region of interest (ROI) that was placed on the inferior glenoid rim. Measurements obtained using the CT Pico method (three readers) and with laser were compared to assess differences between radiological assessment and the reference standard. Each observer performed two repeated measurements from each scapulae (20 for each observer). Mean differences between laser measurements and each CT reader were 18.4% (range, -4 to 61%) for reader 1, 12.4% (range, -15 to 64%) for reader 2, and 11% (range, -14 to 58%) for reader 3. Considering all the 60 measurements made by the three readers, 39 measurements out of 60 (65%) were outside the range [-5%; +5%] while 26 measurements (43%) are outside the range [-10%; +10%]. The largest differences (positive and negative) were +64 and -14 %, respectively. Intra-operator reproducibility was high in most cases (intraclass correlation coefficient (ICC) =0.93, ICC = 0.91, ICC = 0.93 and Lin's Concordance correlation coefficient (CCC) = 0.92, CCC = 0.90, CCC = 0.92 for reader 1 to 3, respectively. However, in five cases the CT Pico measurements showed absolute differences between the first and second measurements that exceeded 10%. The inter-observer variability for CT measurement of the glenoid surface using the CT Pico method was high when compared with laser, in the assessment of glenoid surface in cadaveric specimens, thus the CT Pico method is not reliable and could cause errors in the clinical management of the patient. Level of evidence Level II, Development of diagnostic criteria on consecutive patients (with universally applied reference "gold" standard).