Cardiovascular MRI Reference Ranges for Heart, Aorta, and Pulmonary Artery in Healthy Chinese Children.

BACKGROUND: Cardiovascular magnetic resonance (cardiac MR) reference ranges in Chinese children are lacking. PURPOSE: To establish age- and sex-specific reference ranges for cardiac MR parameters in a cohort of healthy Chinese children. STUDY TYPE: Retrospective. SUBJECTS: One hundred ninety-six healthy children (mean age 9.5 ± 3.6 years, 111 boys). FIELD STRENGTH/SEQUENCE: 1.5 T; balanced steady-state free precession. ASSESSMENT: Biventricular volume and ejection fractions (EF), left atrial (LA) volume, right atrial (RA) area, left ventricular (LV) mass and thickness, aortic root (AR), and main pulmonary artery (MPA) dimensions were measured. Parameters were compared between age groups and sex. The relationships between parameters and age, body mass index (BMI) and body surface area (BSA) were investigated. STATISTICAL TESTS: Independent-samples t tests; Pearson's correlation. A P value <0.05 was considered statistically significant. RESULTS: Generally, boys exhibited greater absolute measurements of LV volume (end-diastolic: 94.4 ± 29.5 vs. 81.3 ± 31.0 mL), LA volume (end-diastolic: 42.6 ± 13.4 vs. 38.0 ± 13.3 mL), RA area (end-diastolic: 11.6 ± 2.5 vs. 10.8 ± 2.6 cm2), LV thickness (base: 4.4 ± 1.1 vs. 3.8 ± 0.9 mm), AR dimensions (annuls: 16.3 ± 2.7 vs. 15.0 ± 2.8 mm), and MPA dimensions (14.3 ± 2.3 vs. 13.1 ± 2.4 mm) than girls did. However, these differences were not observed when the measurements were normalized to BSA (LV volume: 75.3 ± 11.7 vs. 71.9 ± 12.3 mL/m2, P = 0.052; LA volume: 34.8 ± 8.9 vs. 34.5 ± 7.6 mL/m2, P = 0.783; RA area: 9.7 ± 2.3 vs. 10.2 ± 2.3 cm2/m2, P = 0.107; LV thickness: 3.6 ± 0.7 vs. 3.6 ± 0.9 mm/m2, P = 0.990; AR: 13.6 ± 2.7 vs. 14.3 ± 3.4 mm/m2, P = 0.108; MPA: 11.9 ± 2.3 vs. 12.4 ± 2.4 mm/m2, P = 0.118). Boys had greater RV volume (end-diastolic: 98.7 ± 33.5 vs. 82.7 ± 33.1 mL) and LV mass (52.6 ± 20.2 vs. 41.4 ± 16.0 g) compared to girls, irrespective of whether the values were indexed or not for BSA. Additionally, there were significant associations between age, BMI, and BSA with biventricular volume, LA volume, RA area, LV mass and thickness, AR and MPA dimensions in both boys and girls. DATA CONCLUSION: This study suggests reference ranges at 1.5 T for Chinese children. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

Cardiac T1ρ Mapping Values Affected by Age and Sex in a Healthy Chinese Cohort.

BACKGROUND: To facilitate the clinical use of cardiac T1ρ, it is important to understand the impact of age and sex on T1ρ values of the myocardium. PURPOSE: To investigate the impact of age and gender on myocardial T1ρ values. STUDY TYPE: Cross-sectional. POPULATION: Two hundred ten healthy Han Chinese volunteers without cardiovascular risk factors (85 males, mean age 34.4 ± 12.5 years; 125 females, mean age 37.9 ± 14.8 years). FIELD STRENGTH/SEQUENCE: 1.5 T; T1ρ-prepared steady-state free precession (T1ρ mapping) sequence. ASSESSMENT: Basal, mid, and apical short-axis left ventricular T1ρ maps were acquired. T1ρ maps acquired with spin-lock frequencies of 5 and 400 Hz were subtracted to create a myocardial fibrosis index (mFI) map. T1ρ and mFI values across different age decades, sex, and slice locations were compared. STATISTICAL TESTS: Shapiro-Wilk test, Student's t test, Mann-Whitney U test, linear regression analysis, one-way analysis of variance and intraclass correlation coefficient. SIGNIFICANCE: P value <0.05. RESULTS: Women had significantly higher T1ρ and mFI values than men (50.3 ± 2.0 msec vs. 47.7 ± 2.4 msec and 4.7 ± 1.0 msec vs. 4.3 ± 1.1 msec, respectively). Additionally, in males and females combined, there was a significant positive but weak correlation between T1ρ values and age (r = 0.27), while no correlation was observed between the mFI values and age (P = 0.969). DATA CONCLUSION: We report potential reference values for cardiac T1ρ by sex, age distribution, and slice location in a Chinese population. T1ρ was significantly correlated with age and sex, while mFI was only associated with sex. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.

Inter-scanner comparability of Z-scores for native myocardial T1 and T2 mapping.

BACKGROUND: Cardiovascular Magnetic Resonance (CMR) native T1 and T2 mapping serve as robust, contrast-agent-free diagnostic tools, but hardware- and software-specific sources of variability limit the generalizability of data across CMR platforms, consequently limiting the interpretability of patient-specific parametric data. Z-scores are used to describe the relationship of observed values to the mean results as obtained in a sufficiently large normal sample. They have been successfully used to describe the severity of quantifiable abnormalities in medicine, specifically in children and adolescents. The objective of this study was to observe whether z-scores can improve the comparability of T1 and T2 mapping values across CMR scanners, field strengths, and sequences from different vendors in the same participant rather than different participants (as seen in previous studies). METHODS: Fifty-one healthy volunteers (26 men/25 women, mean age = 43 ± 13.51) underwent three CMR exams on three different scanners, using a Modified Look-Locker Inversion Recovery (MOLLI) 5-(3)- 3 sequence to quantify myocardial T1. For T2 mapping, a True Fast Imaging with steady-state free precession (TRUFI) sequence was used on a 3 T Skyra™ (Siemens), and a T2 Fast Spin Echo (FSE) sequence was used on 1.5 T Artist™ (GE) and 3.0 T Premier™ (GE) scanners. The averages of basal and mid-ventricular short axis slices were used to derive means and standard deviations of global mapping values. We used intra-class comparisons (ICC), repeated measures ANOVA, and paired Student's t-tests for statistical analyses. RESULTS: There was a significant improvement in intra-subject comparability of T1 (ICC of 0.11 (95% CI= -0.018, -0.332) vs 0.78 (95% CI= 0.650, 0.866)) and T2 (ICC of 0.35 (95% CI= -0.053, 0.652) vs 0.83 (95% CI= 0.726, 0.898)) when using z-scores across all three scanners. While the absolute global T1 and T2 values showed a statistically significant difference between scanners (p < 0.001), no such differences were identified using z-scores (T1z: p = 0.771; T2z: p = 0.985). Furthermore, when images were not corrected for motion, T1 z-scores showed significant inter-scanner variability (p < 0.001), resolved by motion correction. CONCLUSION: Employing z-scores for reporting myocardial T1 and T2 removes the variation of quantitative mapping results across different MRI systems and field strengths, improving the clinical utility of myocardial tissue characterization in patients with suspected myocardial disease.

Normal ovarian sizes on MRI in pediatric patients: a preliminary study.

BACKGROUND: Ovarian enlargement is one of several findings of pathology, including ovarian torsion. With increasing use of MRI for acute abdominal pain in children, data for normal ovary size and appearance are needed. OBJECTIVE: To provide preliminary data on normal sizes of ovaries on MRI in pediatric patients. MATERIALS AND METHODS: This retrospective IRB-approved study included girls (5 to 17 years of age) with MRI examinations performed for indications not related to the ovaries from 2018 to 2022. For each MRI, coronal T2-weighted single shot fast spin echo and axial T2-weighted fat-saturated images were independently reviewed by three pediatric radiologists who recorded ovary visualization and ovarian linear measurements (3 planes). Ovarian volumes were calculated from linear measurements. Agreement among observers was calculated using kappa statistics and intraclass correlation coefficients. RESULTS: A total of 181 MRIs were reviewed. The left ovary was visualized in 166-176 (92-97%) cases (R1-R3) and the right ovary was visualized in 165-174 (91-96%) cases with excellent agreement among reviewers (left: K = 0.89 [0.84-0.94], right: K = 0.85 [0.79-0.91]). Interrater class coefficient (ICC) for largest single dimension of the ovary was left: 0.83 (CI 0.79-0.87) and right: 0.85 (CI 0.81-0.89). There were significant moderate to strong correlations between ovarian volume and age (left: 0.67 [0.58-0.75], right: 0.66 [0.57-0.74]). CONCLUSION: The ovaries can be adequately visualized and measured on MRI with excellent inter-reader agreement. This study serves as the foundation for developing normative values for ovarian volumes by age on MRI.

Normative Values of the Repetitive Saliva Swallow Test and Clinical Factors Affecting the Test Scores in Healthy Adults.

The Repetitive Saliva Swallow Test (RSST) is a screening test for oropharyngeal dysphagia during which the subject is asked to perform as many empty swallows as possible in 30 s. Previous validation studies found a cutoff value of 3 > swallows as pathological. The aims of this study were to establish the normative values of the RSST and to examine the effect of clinical factors on RSST scores in healthy adults. A cross-sectional study of 280 adults. An equal number of females and males were recruited for each decade of life, ages 20 to 90 years. Patients reporting swallowing difficulties, history of neurologic disorders, or head and neck surgery or radiation were excluded. Data collected included RSST scores, number and type of comorbidities, number of prescribed medications, body mass index, smoking habits, and self-assessment xerostomia questionnaire. The mean RSST score for the entire cohort was 7.01 ± 2.86. Males had a higher RSST score (7.6 ± 3.04 compared to 6.47 ± 2.56, p = 0.001). Age showed an inverse correlation with RSST scores (Pearson's Correlation Coefficient (PCC) = -0.463, p < 0.0001), as well as body mass index, BMI (PCC = -0.2, p < 0.0001), number of co-morbidities (PCC=-0.344, p < 0.0001) and number of prescribed medications (PCC= -0.425, p < 0.0001). Self-reported amount of saliva positively correlated (PCC = 1.05, p = 0.04) with RSST scores. A multivariate logistic regression analysis was performed. Age, sex, BMI, and number of prescribed medications were found as significant independent factors on RSST scores. RSST scores in healthy adults decline with age and are lower in females, individuals taking multiple medications and with higher BMI. Mean RSST for all age groups did not fall beneath the previously established pathological cut-off.

Normative measurements of orbital structures on magnetic resonance images; a cross-sectional study with mini review of the literature.

PURPOSE: Awareness of normative values of extra orbital structures would provide useful information to interpret the radiological images better and use them for diagnostic purposes. This study aimed to reveal the average values of major extraocular structures measured on magnetic resonance images. METHODS: In this retrospective cross-sectional study, magnetic resonance (MR) images of 256 orbits of 128 patients were re-interpreted regarding the measurements of major orbital structures. Extraocular muscles, superior ophthalmic vein, and optic nerve-sheath complex were measured on orbital MR images of these patients. The data distributions were presented by box-plot analyses for each parameter, and the measurement results were analyzed regarding gender and age groups. RESULTS: Lateral rectus muscle thickness (LR), inferior rectus muscle thickness (IR), globe position (GP), and interzygomatic line (IZL) values were higher in the male group than in the female group (p values were < 0.001, 0.003, 0.020, and < 0.001 respectively). LR, the thickness of the superior group muscles (SUP GR), IR, superior oblique muscle thickness (SOBL), and the thickness of optic nerve-sheath complex (ON) values indicated a significant relationship between age groups. There was a significant, positive, and low-level correlation between age and LR, SUP GR, and IR values (p values were < 0.001, 0.001, and < 0.001, respectively). CONCLUSION: This study provides quantitative data on normative values of orbital structures with gender and age group comparisons. Clinicians or surgeons can easily use the measured values to gather diagnostic information from the orbital region.

Pediatric Cardiac Magnetic Resonance Reference Values for Biventricular Volumes Derived From Different Contouring Techniques.

BACKGROUND: Measurement of ventricular volumes and function using MRI is an important tool in pediatric congenital heart disease. However, normal values for children are sparce and analysis methods are inconsistent. PURPOSE: To propose biventricular reference values in children for two MRI postprocessing (contouring) techniques. STUDY TYPE: Retrospective. SUBJECTS: A total of 154 children from two institutions (13.9 ± 2.8 years; 101 male) that were referred for a clinical MRI study. FIELD STRENGTH/SEQUENCE: 1.5 T; balanced steady-state free precession (bSSFP) sequence. ASSESSMENT: Left ventricular (LV) and right ventricular (RV) end-diastolic and end-systolic volumes (LVEDV, LVESV, RVEDV, RVESV) and end-diastolic and end-systolic myocardial mass (LVEDMM, LVESMM, RVEDMM, RVESMM) were measured from short-axis images using two contouring techniques: 1) papillary muscles, trabeculations and the moderator band were included in the ventricular blood volume and excluded from the myocardial mass, 2) papillary muscles, trabeculations and the moderator band were excluded from the ventricular volume and included in the ventricular mass. STATISTICAL TESTS: Univariable and multivariable linear regression models were used to evaluate relationships between sex, weight, height, body surface area (BSA) and age and volumetric results. Reference graphs and tables were created with the LMS-method. Contouring techniques were compared by intraclass correlation, regression analysis and Bland-Altman plots. A P value < 0.05 was considered statistically significant. RESULTS: Height and BSA were significantly associated with LVESV (method 1) and with LVEDV and RVEDV (method 2). LVESV (method 2), RVESV (both methods), RVEDV (method 1), and LVEDMM and RVEDMM (both methods), showed significant associations with height and weight. LVSV and RVSV (both methods) were significantly associated with BSA and weight. RVESV (method 1) was significantly associated with age. Gender showed significant associations for all parameters. DATA CONCLUSION: The proposed pediatric reference values can be used in the diagnosis and follow-up of congenital or acquired heart disease and for research purposes. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.

Healthy Adult Left and Right Ventricular Torsion and Torsion Rates With MR-Feature Tracking.

BACKGROUND: The clinical value of myocardial torsion quantification in prognostic assessment and risk stratification of various cardiovascular diseases is gradually being recognized. However, normal values of left and right ventricular (LV and RV) torsion and torsion rates (TRs) have not been fully determined, and their correlation with age and gender has not been well studied. PURPOSE: To establish normal ranges of biventricular torsion, peak systolic and diastolic TRs using magnetic resonance feature tracking (MR-FT) technique based on a large sample of healthy adults, and further investigate their relationship with age and gender. STUDY TYPE: Retrospective. POPULATION: 566 Healthy adults (312 males, aged 43 ± 10 years; 254 females, aged 43 ± 11 years). FIELD STRENGTH/SEQUENCE: 1.5T/gradient echo. ASSESSMENT: Biventricular torsion, peak systolic, and diastolic TRs. STATISTICAL TESTS: Shapiro-Wilk test, Student's t-test, Mann-Whitney-U test, linear regression, intraclass correlation coefficient, Bland-Altman analysis. Differences were regarded as statistically significant at P < 0.05. RESULTS: Women demonstrated greater magnitudes of left ventricle (LV) torsion (1.23 ± 0.44 vs. 1.00 ± 0.42°/cm), peak systolic TR (9.69 ± 3.70 vs. 8.27 ± 3.73°/cm*sec), peak diastolic TR (-7.78 ± 2.82 vs. -6.06 ± 2.44°/cm*sec), and RV torsion (2.20 ± 1.23 vs. 1.65 ± 1.11°/cm*sec), peak systolic TR (16.07 ± 8.18 vs. 12.62 ± 7.08°/cm*sec), peak diastolic TR (-15.39 ± 6.53 vs. -11.70 ± 6.03°/cm*sec). For both genders, the magnitudes of LV and RV torsion, peak systolic, and diastolic TRs increased linearly with age. All the measurements of biventricular torsion, peak systolic and diastolic TRs achieved good to excellent intraobserver and interobserver reproducibility, with all intraclass correlation coefficients >0.70. DATA CONCLUSION: The present study systematically provided age- and sex-stratified reference values for LV and RV torsion and TRs using MR-FT technique. Women and aging are associated with greater magnitudes of biventricular torsion, peak systolic, and diastolic TRs. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

Variability of the optic nerve sheath diameter on brain computed tomography in Turkish children based on sex and age.

BACKGROUND: Optic nerve sheath diameter (ONSD) measurement is a noninvasive method that can be used for intracranial pressure monitoring. Several studies have investigated normal ONSD values in children, but no general consensus has been reached yet. OBJECTIVES: The aim of our study was to reveal normal ONSD, eyeball transverse diameter (ETD), and ONSD/ETD values on brain computed tomography (CT) in healthy children aged 1 month to 18 years. METHODS: Children admitted to the emergency department with minor head trauma and had normal brain CT were included in the study. The demographic characteristics of the patients (age and sex) were recorded, and the patients were divided into four age groups: 1 month to 2 years, 2 to 4 years, 4 to 10 years, and 10 to 18 years. RESULTS: The images of 332 patients were analyzed. When the median values of all measurement parameters (right and left ONSD, ETD, and ONSD/ETD) were compared between the right and left eyes, no statistically significant differences were found. When the same parameters were compared according to age group, the ONSD and ETD values differed significantly (values of males were found to be higher), but the ONSD proximal/ETD and ONSD middle/ETD values did not differ significantly. CONCLUSION: In our study, normal ONSD, ETD, and ONSD/ETD values were determined according to age and sex in healthy children. As the ONSD/ETD index did not statistically significantly differ according to age and sex, diagnostic studies for traumatic brain injuries can be performed using the index.

Semi-automated 3-dimensional analysis of the normal foot and ankle using weight bearing CT - A report of normal values and bony relationships.

BACKGROUND: Foot and ankle deformities have translational and rotational components in multiple planes, at multiple levels. Semi-automatic segmentation is a relatively new technology, which when used with weight-bearing CT (WBCT), can build an accurate model of the foot and calculate the orientation and relationships of bones under physiological load. However, few papers report reference values using these techniques. We report normative values for key bony relationships based on semi-automated analysis of WBCT. METHODS: This was a single-centre, retrospective analysis of 100 feet without deformity from 55 adult patients undergoing WBCT as part of routine clinical activity (mean age 40.5 ± 17.3 years). Imaging was analysed using Bonelogic 2.1 (DISIOR, Finland). Semi-automatic segmentation was used to compute the various bony axes in 3-dimensional space. Selected coronal, axial and sagittal plane relationships were then calculated for bones of the hindfoot, midfoot and forefoot. RESULTS: Data is presented on axial and sagittal plane relationships between the metatarsals in the forefoot, and the metatarsals and cuneiforms in the midfoot. In the hindfoot, the calcaneal pitch, talar-first-metatarsal angles, talonavicular coverage angles and Saltzman angles are reported. Coronal plane axes and their relationships are reported at multiple levels from hindfoot to forefoot. Results are presented as mean values with standard deviations and 95% confidence intervals. CONCLUSIONS: We present an observational analysis of the normal values from non-deformed feet. We highlight the major relationships in the axial, sagittal and coronal planes as obtained by semi-automated analysis of WBCT. This data may serve as a reference for future research. LEVEL OF EVIDENCE: Basic science study.

Defining Normal Ranges of Skeletal Muscle Area and Skeletal Muscle Index in Children on CT Using an Automated Deep Learning Pipeline: Implications for Sarcopenia Diagnosis.

BACKGROUND. Skeletal muscle area (SMA), representing skeletal muscle cross-sectional area at the L3 vertebral level, and skeletal muscle index (SMI), representing height-normalized SMA, can serve as markers of sarcopenia. Normal SMA and SMI values have been reported primarily in adults. OBJECTIVE. The purpose of this study was to use an automated deep learning (DL) pipeline for muscle segmentation on abdominal CT to define normative age- and sex-based values for pediatric muscle cross-sectional area as a guide for diagnosis of sarcopenia in children. METHODS. This retrospective study reviewed records of patients who underwent abdominal CT at Cincinnati Children's Hospital Medical Center from January 1, 2009, to January 3, 2019. Patients were excluded on the basis of age outside of the eligible range (2.00-18.99 years), body mass index (BMI) outside of 5-95% age-based percentiles using CDC and WHO growth charts, known medical condition, medication use, support devices, surgery, or missing axial images at the L3 level. A previously validated automated DL pipeline was used to identify an axial slice at L3 and segment skeletal muscle to generate SMA and SMI. Pearson correlation coefficients were computed. Quantile regression analysis was used to plot SMA and SMI as functions of age and sex and to determine age- and sex-based percentile values. RESULTS. Of 8817 patients who underwent abdominal CT during the study period, 2168 (mean age, 12.3 ± 4.3 [SD] years; 1125 female patients, 1043 male patients) met inclusion criteria. Mean BMI-for-age percentile based on CDC and WHO growth charts was 64.8% ± 25.3% for female patients and 61.4% ± 25.8% for male patients. SMA showed strong correlation with weight, height, age, and BMI for male (0.79-0.94) and female (0.75-0.90) patients; SMI showed weak-to-moderate correlation with weight, height, age, and BMI for male (0.25-0.57) and female (0-0.43) patients. Normal SMA and SMI ranges for age and sex were expressed as curves and as a lookup table, identifying 54 male and 59 female patients with muscle measurements below the 5th percentile regression curve. CONCLUSION. By using an automated DL pipeline in a large sample of carefully selected children, normal ranges for SMA and SMI were calculated as functions of age and sex. CLINICAL IMPACT. The normative values should aid the diagnosis of sarcopenia in children.

Comparing a knowledge-based 3D reconstruction algorithm to TomTec 3D echocardiogram algorithm in measuring left cardiac chamber volumes in the pediatric population.

BACKGROUND: Three-dimensional echocardiography (3DE) is an emerging method for volumetric cardiac measurements; however, few vendor-neutral analysis packages exist. Ventripoint Medical System Plus (VMS3.0+) proprietary software utilizes a validated Magnetic resonance imaging (MRI) database of normal ventricular and atrial morphologies to calculate chamber volumes. This study aimed to compare left ventricular (LV) and atrial (LA) volumes obtained using VMS3.0+ to Tomtec echocardiography analysis software. METHODS: Healthy controls (n = 98) aged 0-18 years were prospectively recruited and 3D DICOM datasets focused on the LV and LA acquired. LV and LA volumes and ejection fractions were measured using TomTec Image Arena 3D LV analysis package and using VMS3.0+. Pearson correlation coefficients, Bland-Altman's plots, and intraclass coefficients (ICC) were calculated, along with analysis time. RESULTS: There was a very good correlation between Ventripoint Medical System (VMS) and Tomtec LV systolic (r2  = .88, ICC .89 [95% CI .81, .94]), and diastolic (r2  = .88, ICC .90 [95% CI .77, .95]) volumes, and between VMS and Tomtec LA diastolic (r2  = .75, ICC .89 [95% CI .81, .93]) and systolic (r2  = .88, ICC .91 [95% CI .78, .96]) volumes on linear regression models. Natural log transformations eliminated heteroscedasticity, and power transformations provided the best fit. The time (mins) to analyze volumes using VMS were less than using Tomtec (LV VMS 2.3 ± .5, Tomtec 3.3 ± .8, p < .001; LA: VMS 1.9 ± .4, Tomtec 3.4 ± 1.0, p < .001). CONCLUSIONS: There was a very good correlation between knowledge-based (VMS3.0+) and 3D (Tomtec) algorithms when measuring 3D echocardiography-derived LA and LV volumes in pediatric patients. VMS was slightly faster than Tomtec in analyzing volumetric measurements.

Normative Transesophageal Echocardiographic Values of Cardiac Structures in the Indian Population-Indian Normative TEE Measurements (INTEEM) Study.

OBJECTIVES: Information on normative reference values for cardiac structures is critical for the accurate application of echocardiography for guiding clinical decision-making. Many studies using transthoracic echocardiography (TTE) have shown that Indians have smaller diameters of various cardiac structures. There are no normative studies for transesophageal echocardiography (TEE). The authors observed dimensions of various cardiac structures in healthy Indian patients under general anesthesia using TEE and compared them with existing guidelines from non-Indian data. DESIGN: The Indian Normative TEE Measurements study was a multicenter, prospective observational study conducted in India. SETTING: Operating rooms for noncardiac surgeries in tertiary care-level hospitals. PARTICIPANTS: Adult patients undergoing noncardiac surgery who were free from any cardiac, respiratory, and renal diseases and had no contraindications for TEE. INTERVENTIONS: After inducing general anesthesia and achieving stable hemodynamic conditions, a comprehensive TEE examination was performed and various measurements were made. MEASUREMENTS AND MAIN RESULTS: For each of the 83 patients undergoing noncardiac surgery, 39 various measurements for left ventricle, right ventricle, both atria, and all valves were made. This included diameters and functional parameters. They were analyzed in a vendor-neutral software off-line. The absolute values of many of the measurements were higher in men, but when indexed to body surface area (BSA) they were similar in both sexes. The values were lower than most of the Western data but matched previous Indian studies using TTE. CONCLUSIONS: The authors present normative values of various echocardiographic parameters using TEE. Because of its variations, it is recommended to use India-specific data to make decisions in Indian patients. It may be prudent to use BSA-indexed values during decision-making.

Dynamic Mediolateral Patellar Translation Is a Sex- and Size-Independent Parameter of Adult Proximal Patellar Tracking Using Dynamic 3 Tesla Magnetic Resonance Imaging.

PURPOSE: To provide normal values for physiological patellofemoral tracking in a representative group of healthy individuals, as well as sex differences, using real-time 3T-magnetic resonance imaging (MRI) and to test for the reliability of the presented technique. METHODS: One hundred knees of healthy individuals with no history of patellofemoral symptoms were scanned with dynamic MRI sequences, during repetitive cycles of flexion (40°) and full extension. Within a 30-seconds time-frame, three simultaneous, transverse slices were acquired. Dynamic mediolateral patellar translation (dMPT) and dynamic patellar tilt (dPT) were measured on two occasions by two independent examiners. Common radiological parameters were measured using static MRI, and correlations were calculated. RESULTS: 100 knees (53 right, 47 left; age: 26.7 ± 4.4 years; BMI: 22.5 ± 3.1) of 57 individuals (27 females, 30 males) were included. Mean height was 170.1 ± 7.7 cm in women and 181.8 ± 6.4 cm in men. Average patella diameter was 37.9 ± 2.7 (95% CI 37.1-38.7) mm in women and 42.4 ± 3.2 (95% CI 41.5-43.3) mm in men. In females, the patellar diameters and intercondylar distances were significantly smaller than in males (P < .001). Radiological parameters for patellar maltracking were within the normal range. During the range of motion, mean dMPT was 1.7 ± 2.4 (95% CI .9-2.5) mm in females and 1.8 ± 2.7 (95% CI 1.1-2.6) mm in males (P = .766). Mean dPT was 1.3 ± 2.9° (95% CI .4-2.1°) in females and -0.2 ± 3.8° (95% CI -1.2-.9°) in males (P = .036). Neither dMPT nor dPT was correlated with height, BMI, or patellar diameter. Intercondylar distance correlated weakly with dPT (r = -.241; P = .041). Intra- and interrater reliability were excellent for dMPT and dPT. CONCLUSION: Dynamic mediolateral patellar translation is a size- and sex-independent parameter for proximal patellar tracking. In healthy individuals without patellofemoral abnormalities normal dMPT proximal to the trochlea groove was 1.7 ± 2.5 (1.2-2.2) mm, independent of size or sex. Normal dPT showed a dependency on sex and was 1.3 ± 2.9 (.4-2.1)° in women and -0.2 ± 3.8 (-1.2-0.9)° in men. LEVEL OF EVIDENCE: Level II, diagnostic study.

Baseline Values of the Compensatory Reserve Index in a Healthy Pediatric Population.

The objective of this study is to describe the compensatory reserve index (CRI) baseline values in a healthy cohort of healthy pediatric patients and evaluate the existing correlation with other physiological parameters that influence compensatory hemodynamic mechanisms. CRI is a computational algorithm that has been broadly applied to non-invasively estimate hemodynamic vascular adaptations during acute blood loss. So far, there is a lack of baseline values from healthy individuals, which complicates accurately estimating the severity of the hemodynamic compromise. Additionally, the application of this technology in pediatric populations is limited to a few reports, highlighting a marked variability by age, weight, and other physiological parameters. The CRI of 205 healthy subjects from 0 to 60 years of age were prospectively evaluated from January to February 2020 at several public outpatient clinics in El Salvador; vital signs and sociodemographic data were also collected during this period. After data collection, baseline values were classified for each age group. Multiple correlation models were tested between the CRI and the other physiological parameters. CRI value varies significantly for each age group, finding for patients under 18 years old a mean value lower than 0.6, which is currently considered the lower normal limit for adults. CRI presents strong correlations with other physiological variables such as age, weight, estimated blood volume, and heart rate (R > 0.8, R2 > 0.6, p < 0.0001). There is significant variability in the CRI normal values observed in healthy patients based on age, weight, estimated blood volume, and heart rate.

Quantitative magnetic resonance imaging measures of three-dimensional aortic morphology in healthy aging and hypertension.

Automated segmentation of three-dimensional (3D) aortic magnetic resonance imaging (MRI) renders a possible retrospective selection of any location to perform quantification of aortic caliber perpendicular to its centerline and provides regional and global 3D biomarkers such as length, diameter, or volume. However, normative age-related values of such measures are still lacking. The aim of this study was to provide normal values for 3D aortic morphological measures and investigate their changes in aging and hypertension. This was a retrospective study, in which 119 healthy controls (HC: 48 ± 14 years, 61 men) and 82 hypertensive patients (HT: 60 ± 14 years, 43 men) were enrolled. 1.5 and 3 T/3D steady state free precession or spoiled gradient echo were used. Automated 3D aortic segmentation provided aortic length, diameter, volume for the ascending (AAo), and descending aorta (DAo), along with cross-sectional diameters at three aortic landmarks. Age, sex, body surface area (BSA), smoking, and blood pressures were recorded. Both groups were divided into two subgroups (≤50 years, >50 years). Statistical tests performed were linear regression for age-related normal values and confidence intervals, Wilcoxon rank sum test for differences between groups (HC or HT), and multivariate analysis to identify main determinants of aortic morphological changes. In HC, linear regression revealed an increase in the AAo (respectively DAo) length by 2.84 mm (7.78 mm), maximal diameter by 1.36 mm (1.29 mm), and volume by 4.28 ml (8.71 ml) per decade. AAo morphological measures were higher in HT patients than in HC both ≤50 years but did not reach statistical significance (length: +2 mm, p = 0.531; diameter: +1.4 mm, p = 0.2936; volume:+6.8 ml, p = 0.1857). However, length (+6 mm, p = 0.003), maximal diameter (+4 mm, p < 0.001) and volume (+12 ml, p < 0.001) were significantly higher in HT patients than in HC, both >50 years. In a multivariate analysis, age, sex, and BSA were the major determinants of aortic morphology, irrespective of the presence of hypertension. Global and segmental aortic length, volume, and diameters at specific landmarks were automatically measured from 3D MRI to serve as normative measures of 3D aortic morphology. Such indices increased significantly with age and hypertension among the elderly subjects. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 3.

Reference Values for Ventricular Volumes and Pulmonary Artery Dimensions in Pediatric Patients with Transposition of the Great Arteries After Arterial Switch Operation.

BACKGROUND: Pulmonary artery (PA) anatomy in patients with transposition of the great arteries (TGA) after arterial switch operation (ASO) with Lecompte manoeuvre is different compared to healthy subjects, and stenoses of the PA are common. Magnetic resonance imaging (MRI) is an excellent imaging modality to assess PA anatomy in TGA patients. However, disease-specific reference values for PA size are scarce. PURPOSE: To establish disease-specific reference ranges for PA dimensions and for biventricular volumes and mass. STUDY TYPE: Retrospective. SUBJECTS: A total of 69 pediatric patients with TGA after ASO (median age 12.6 years; range 5-17.8 years; 13 females and 56 males). FIELD STRENGTH/SEQUENCE: 3.0 T, steady-state free precession (SSFP) and gradient echo cine sequences and four-dimensional time-resolved magnetic resonance angiography with keyhole. ASSESSMENT: Right and left PA (RPA, LPA) were each measured at three locations during its course around the aorta. Ventricular volumes, mass, and ejection fraction were measured from a stack of short axis cine images. STATISTICAL TESTS: The lambda-mu-sigma (LMS) method of Cole and Green, univariate and multivariate linear models, and t-test. RESULTS: Centile graphs and tables for PA dimensions, biventricular volumes, mass, and ejection fraction were created. Univariate linear analysis showed significant associations (P < 0.05) between body surface area (BSA), height, and weight with systolic MPA and RPA diameter. In multivariate linear analysis, only BSA remained a strong predictor for main PA and RPA diameters. For biventricular volumes, the univariate linear model revealed a strong influence of BSA, height, weight, and age (all P < 0.05). On multivariate linear analysis, only body height remained associated. DATA CONCLUSION: Uni- and multivariate linear analyses showed a strong association between BSA and PA diameters, as well as between height and biventricular volumes, and therefore, centile tables and graphs are presented accordingly. Our data may improve MR image interpretation and may serve as a reference in future studies. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 2.

Revising nerve conduction reference limits.

INTRODUCTION/AIMS: Our electrodiagnostic laboratory uses reference limits (RL) that have been handed down for four decades. With changes in instrumentation and technique, we wish to know if our RL should be modified. It is also useful to have RL based on patient demographics. METHODS: Latency and velocity data from motor nerve conduction studies of 740 adult patients studied over an 8 mo period were tabulated. RL were derived using both extrapolated reference value (ERef) and multi-variable extrapolated reference value (MeRef) methods. RESULTS: Distal latency values showed a significant but weak correlation with age and/or height. ERef limits for the median and ulnar nerve latency (3.96 and 3.45 ms, respectively) were very similar to current laboratory limits (3.9 and 3.3 ms, respectively). ERef limits for the tibial and fibular nerve latency (5.1 and 4.95 ms, respectively) were slightly shorter. Ulnar velocity did not depend on age or height. The ERef limit was the same as our present laboratory limit (50 m/s). Median and tibial velocity limits decreased with age (R2  > 0.25). Fibular motor nerve conduction limits decreased with age and height (R2  = 0.39). DISCUSSION: ERef and MeRef were useful to validate and revise our latency and velocity RL. We will use ERef limits for tibial and fibular latency. MeRef generated linear regression equations based on age and/or height will be used for conduction velocity analysis of median, fibular, and tibial nerves. This will increase the specificity of our values.

MeRef: Multivariable extrapolated reference values in motor nerve conduction studies.

INTRODUCTION: In this study we describe a method called "multivariable extrapolated reference values" (MeRef) that derives reference values (RVs) using patient data and includes the dependence of these variables on multiple patient demographic variables, such as age and height. METHODS: Computer simulations were used to generate "normal" and "patient" nerve conduction data. Median, ulnar, and tibial motor nerve conduction data from 500 patients studied were tabulated. Data were analyzed using the MeRef method. RESULTS: The simulations showed great similarity between RVs obtained from MeRef of "patient" data and traditional analysis of "normal" data. In the real patient data, MeRef gave RVs as regression equations based on patient age and/or height. DISCUSSION: MeRef can provide RVs by including patient demographic data and does not require subject grouping. It provides parameters of multivariable linear regression and standard deviation, and requires a few hundred patient studies to define reference values.

Body mass index changes: an assessment of the effects of age and gender using the e-norms method.

BACKGROUND: To validate e-norms methodology in establishing a reference range for body mass index measures. A new method, the extrapolated norms (e-norms) method of determining normal ranges for biological variables is easy to use and recently was validated for several biological measurements. We aimed to determine whether this new method provides BMI results in agreement with established traditionally collected BMI values. METHODS: We applied the e-norms method to BMI data from 34,384 individuals and compared the ranges derived from this method with those from a large actuarially based study and explored differences in the normal range by gender, and age. RESULTS: The e-norms derived range of healthy BMI in adults is from 22.7 to 30.6, and showed that BMI is consistently higher in men than in women and increases with age, except in subjects aged 80-98 years in whom healthy BMI appears to be lower. CONCLUSIONS: Our e-norms derived healthy BMI ranges agree with traditionally obtained actuarially based methods, supporting the validity and ease of use of our method.