Measurements In Pediatric Patients Research Articles

Accuracy of non-invasive core temperature monitoring in infant and toddler patients: a prospective observational study.

Careful perioperative temperature management is important because it influences clinical outcomes. In pediatric patients, the esophageal temperature is the most accurate indicator of core temperature. However, it requires probe insertion into the body cavity, which is mildly invasive. Therefore, a non-invasive easily and continuously temperature monitor system is ideal. This study aimed to assess the accuracy of Temple Touch Pro™ (TTP), a non-invasive temperature monitoring using the heat flux technique, compared with esophageal (Tesoph) and rectal (Trect) temperature measurements in pediatric patients, especially in infants and toddlers. This single-center prospective observational study included 40 pediatric patients (< 3years old) who underwent elective non-cardiac surgery. The accuracy of TTP was analyzed using Bland-Altman analysis and compared with Tesoph or Trect temperature measurements. The error was within ± 0.5°C and was considered clinically acceptable. The bias ± precision between TTP and Tesoph was 0.09 ± 0.28°C, and 95% limits of agreement were - 0.48 to 0.65°C (error within ± 0.5°C: 94.0%). The bias ± precision between TTP and Trect was 0.41 ± 0.38°C and 95% limits of agreement were - 0.35 to 1.17°C (error within ± 0.5°C: 68.5%). In infants, bias ± precision with 95% limits of agreement were 0.10 ± 0.30°C with - 0.50 to 0.69°C (TTP vs. Tesoph) and 0.35 ± 0.29°C with - 0.23 to 0.92°C (TTP vs. Trect). Core temperature measurements using TTP in infants and toddlers were more accurate with Tesoph than with Trect. In the future, non-invasive TTP temperature monitoring will help perioperative temperature management in pediatric patients.

Hindfoot Alignment in Pediatrics: The Relationship Between Hindfoot Moment Arm and Hindfoot Alignment Angle.

Various measurements are used to evaluate hindfoot alignment and determine appropriate treatment, though the best tool is not known. Few studies have examined the relationship between these measurements in pediatric patients. This study sought to compare Hindfoot Moment Arm (HMA) and Hindfoot Alignment Angle (HAA) in evaluation of pediatric hindfoot deformity. This was a retrospective cohort study of pediatric patients by age: school-aged (7 to 10 years old), preadolescents (11 to 14), and adolescents (15 to 18). A total of 10 males and 10 females were randomly selected for each cohort from patients with available hindfoot radiographs. HMA and HAA were measured by 2 independent reviewers. Pearson correlation of HMA and HAA was performed by age cohort. Multivariable linear regression was used to investigate the association of HMA and HAA adjusting for age, sex, height, and weight. Sixty participants were analyzed. Interrater reliability was found to be excellent for HMA and HAA (ICC=0.996 and 0.992, respectively). HMA was 8.7±9.4mm in school age, 5.7±6.7 mm in preadolescents, and 2.5±13.0 mm among adolescents (P=0.153). HAA was 6.3±9.7 degrees in school age, 6.7±8.6 degrees in preadolescents, and 6.0±14.5 degrees among adolescents (P=0.983). The Pearson correlation coefficient was 0.78 (CI: 0.51-0.91) for school-aged, 0.92 (CI: 0.81-0.97) for preadolescents, and 0.86 (CI: 0.67-0.94) for adolescents. Using multivariable regression, each degree increase in HAA, increased HMA by 0.77 mm. Age, height, and weight were not found to be independent predictors of HMA. HMA and HAA were both found to be reliable measurements across all age cohorts. When comparing across age cohorts, neither HMA nor HAA differed significantly (P=0.153 and 0.983, respectively). Furthermore, Pearson correlation demonstrated a linear relationship between HMA and HAA. When evaluating hindfoot deformity, surgeons may assess hindfoot alignment via either HMA or HAA regardless of patient age. The authors support the use of HMA for clinical and academic purposes as HMA is considerably simpler to measure. Level III.

Headache and Other Factors Modifying Cerebrospinal Fluid Opening Pressure in Pediatric Patients.

Cerebrospinal fluid opening pressure values are associated with various neurologic diseases; however, numerous factors can modify this measurement. This study aims to describe factors related to modifications in opening pressure measurements in pediatric patients. Methods: A retrospective analysis of lumbar punctures in pediatric patients conducted by the neuropediatrics group with institutional standardization. Bivariate and linear regression analyses were performed to determine the association between opening pressure and variables included in the study. Results: 544 events, median age 107 months, median opening pressure 19.7 cm H2O. Bivariate analysis found no association with medication use; anesthetics that increased opening pressure were remifentanil (P = .02) and propofol (P = .05), along with a positive linear correlation between opening pressure and age (P < .0001). Multiple linear regression analysis revealed that age, BMI, male gender, and remifentanil use were associated with an increase in opening pressure, whereas corticosteroid withdrawal was associated with a reduction in opening pressure. There is an interaction between age and headache, with an association with increased opening pressure up to around 140 months. Conclusion: This study identifies factors associated with changes in opening pressure, crucial for estimating normal opening pressure values in children. Headaches, anesthetic use, and corticosteroid withdrawal are confirmed as significant factors.

The negative impact of levothyroxine treatment on urinary luteinizing hormone measurements in pediatric patients with thyroid disease.

Previous studies suggest urinary luteinizing hormone (LH) and follicle-stimulating hormone (FSH) measurements by immunofluorometric assays (IFMA) as noninvasive alternatives to serum assays for puberty assessment. However, these studies excluded patients with other endocrine disorders and those taking medications. Besides, the recent discontinuation of IFMA manufacturing is a concern. We explored the utility of luminometric assays (LIA) for urinary gonadotropins and thyroid-stimulating hormone (TSH) determinations in euthyroid patients with thyroid pathologies. We used LIA and IFMA assays to measure serum and first-morning-voided (FMV) urine LH, FSH, and TSH concentrations in euthyroid patients with various thyroid disorders. Of the 47 euthyroid patients with normal serum TSH (S-TSH) levels, 14 were receiving levothyroxine therapy. FMV total urinary LH (U-LH) concentrations correlated significantly with those measured in serum using either LIA (r=0.67, P<.001) or IFMA (r=0.83, P=.003) in patients not receiving levothyroxine treatment; however, no significant correlation could be detected in patients receiving levothyroxine regardless of the assay method (for LIA: r=0.50, P=.08 and IFMA r=0.44, P=.15). Urinary TSH (U-TSH) concentrations correlated poorly with those in serum in both the untreated and the treated groups (r=-0.13, P=.49, and r=-0.45, P=.11, respectively). FMV total U-LH determinations by LIA can be used to assess pubertal development in patients with thyroid pathology, provided the euthyroid patient is not on levothyroxine treatment. U-TSH measurements by LIA cannot replace invasive S-TSH measurements at least in patients with normal S-TSH levels. Further research may reveal the utility of U-TSH determinations in patients with elevated S-TSH levels.

Assessing biomechanical corrections: A comparison between Corvis ST and ICare tonometer for intraocular pressure measurement

This study aims to compare the accuracy of IOP measurements in pediatric patients using two different tonometers: ICare PRO and Corvis ST (CST). However, the choice of tonometers may vary between screening centers, depending on patient suitability. To address this, we enrolled 30 patients with retinopathy of prematurity over a period of 33 days for experimentation. A head-to-head comparison revealed a strong correlation between the Corvis ST (CST) and ICare PRO tonometers (r = 0.867). Furthermore, no significant difference was observed in IOP values obtained with the Corvis ST (CST) and ICare PRO tonometers (P > 0.05). However, it is worth noting that the Corvis ST (CST) measurements were significantly higher than those obtained from the ICare PRO tonometers (P < 0.05). In conclusion, this study demonstrates that the Corvis ST (CST) tonometer exhibits a high correlation coefficient comparable to that of the ICare PRO tonometer, making it a reliable tool for assessing IOP in pediatric patients. These findings are crucial for enhancing our understanding of the physiological function of melatonin in the eye and its potential to target melatonin receptors and their complexes for addressing various eye pathologies.

Comparative efficacy of finger versus forehead Plethysmographic Variability Index monitoring in pediatric surgical patients.

The Plethysmographic Variability Index can be measured by both finger and forehead probes. Vasoconstriction may jeopardize the reliability of finger PVI measurements in pediatric patients undergoing surgery. However, forehead vasculature exhibits more marked resistance to alterations in the vasomotor tonus. Our aim was to compare the Plethysmographic Variability Index measured via finger or forehead probes in mechanically ventilated pediatric surgery patients in terms of their ability to predict fluid responsiveness as well as to determine the best cut-off values for these two measurements. A total of 50 pediatric patients undergoing minor elective surgery were included after provision of parental consent and ethics committee approval. Perfusion index measured at the finger or forehead and Plethysmographic Variability Index monitoring comprised the primary assessments. Hemodynamic parameters monitored included perfusion index, Plethysmographic Variability Index, and cardiac output. A ≥ 15% increase in cardiac output following passive leg raise maneuver was considered to show fluid responsiveness. Two groups were defined based on fluid responsiveness: Group R (responsive) and Group NR (non-responsive). Student's t-test, Mann-Whitney U test, DeLong test, and ROC were used for statistical analysis. The area under curve for finger and forehead Plethysmographic Variability Index prior to passive leg raise maneuver were 0.699 (p=.011) and 0.847 (p < .001), respectively. The sensitivity for finger and forehead measurements at a cut-off value of ≤14% was 92.9% and 96.4%, and 45.4% and 72.7%, respectively. Although forehead and finger Plethysmographic Variability Index monitoring were similarly sensitive in predicting fluid responsiveness in pediatric surgical patients, the former method provided higher specificity. The best cut-off value for PVI measurements with forehead and finger probes was found to be 14%.

Evaluation and Treatment of Disorders of Phosphate Balance

The purpose of this article is to review (1) the molecular mechanisms and hormonal factors involved in phosphate handling and regulation, (2) how to appropriately interpret serum and urine phosphate measurements in pediatric patients, (3) the pathophysiology of hypophosphatemic and hyperphosphatemic conditions, and (4) current strategies for treatment of hypophosphatemia and hyperphosphatemia in pediatric patients. For decades, treatment of some hypophosphatemic conditions like X-linked hypophosphatemic rickets (XLH), characterized by a primary increase in fibroblast growth factor 23 (FGF23) activity, consisted of non-specific therapy with phosphate supplementation and calcitriol administration. However, in the past few years, burosumab, a targeted anti-FGF23 antibody, has been developed, representing a promising new medication for the treatment of pediatric XLH patients. The treatment of hyperphosphatemic conditions like chronic kidney disease (CKD) consists of dietary phosphate restriction and enteral phosphate binders; however, the development of new binders and inhibitors of cellular phosphate transporters may offer additional treatment options in the future. The evaluation and treatment of disorders of phosphate balance in children is complex, as numerous interrelated mechanisms and hormones are involved in phosphate handling and regulation. Knowledge of the pathophysiology of hypophosphatemic and hyperphosphatemic conditions informs optimal diagnostic and treatment strategies.

Utility of functional lumen imaging probe in esophageal measurements and dilations: a single pediatric center experience.

Pediatric esophageal stenosis can be challenging to manage due to post-dilation tissue response involving fibroblast activity resulting in scar reformation. The functional lumen imaging probe (FLIP) uses high-resolution impedance planimetry to measure key luminal parameters during a volume-controlled distension. We sought to evaluate the safety as well as possible settings of EndoFLIP and EsoFLIP in the pediatric population. We performed a retrospective chart review of all patients that had EndoFLIP (with and without balloon dilation) or EsoFLIP done between July 2017 and May 2018. Eighteen patients were identified and 19 FLIP procedures were performed during esophagogastroduodenoscopy (10 EndoFLIP, 6 EndoFLIP + traditional balloon dilation, 3 EsoFLIP). Median age for the population was 13.7years. Dysphagia was the most common chief complaint prior to endoscopic intervention. EndoFLIP measurements were most commonly taken at 20ml and/or 30ml of infusion. Diameter, compliance, cross-sectional area, and distensibility index were similar between infusion volumes. Median procedure time of the EndoFLIP + traditional balloon dilation group was longer (60.5min) than the median procedure time of the EsoFLIP group (35min, p = 0.12). Median fluoroscopy time of the EndoFLIP + traditional balloon dilation group was 0.6min and the median fluoroscopy time of the EsoFLIP group was 0.5min (p = 0.79). EndoFLIP + traditional balloon dilation was associated with a smaller diameter increase compared to EsoFLIP (2.2mm vs. 4mm; p = 0.09). There were no complications. Functional lumen imaging probe (FLIP) can safely provide important luminal measurements in pediatric patients with esophageal stenosis, and may guide therapy. Esophageal dilation using EsoFLIP may yield a larger diameter change and may potentially reduce procedure time when compared to traditional balloon dilation. Pediatric patients with epidermolysis bullosa and esophageal stenosis responded well to EsoFLIP dilation.

Surprising interobserver and intra-observer variability in pediatric testicular ultrasound volumes

Testicular volume (TV) can be obtained by either scrotal ultrasound (SU) or orchidometer. Scrotal ultrasound allows for a more objective measurement; however, the interobserver and intra-observer variability of TV measurements has not been rigorously studied. The authors measured intra-observer and interobserver variability of SU TV measurements in pediatric patients to assess the reliability and reproducibility of SU. Special attention was paid to how often a 20% discrepancy in TV was noted as this has previously been utilized as an indication for varicocelectomy. Patients with an indication for SU or undergoing an ultrasound for another reason were prospectively recruited. Two different urologic specific ultrasound technicians (A and B) performed SU to assess interobserver variability. A second measurement was taken by technician A within 90 days to assess intra-observer variability (A vs A1). The technicians were blinded to other ultrasound results. Fourteen patients (28 testes, 56 volume measurements) were included in the intra-observer group and 17 patients (34 testes, 68 volume measurements) in the interobserver group. The mean time to repeat intra-observer ultrasound measurements (range) was 46 days (23-84). Mean age (range) in the intra-observer group was 14.3 years (11-19) and 14.1 years (11-19) in the interobserver group. Indication for ultrasound was varicocele (n=6), scrotal pain (4), hydronephrosis (3), hydrocele (2), epididymal cyst (2), posterior urethral valves (1), and testis asymmetry (1). Utilizing Bland-Altman analysis and plots, variability was seen in both intra-observer and interobserver measurements. The mean values for testicular sizes for technician A and technician B were 13.0±9.7cm3 vs 13.8±9.9cm3, respectively. The mean values for TV measurement for technician A's first and second measurements (A, A1) were 14.3±9.7cm3 and 14.8±8.9cm3, respectively. An errant 20% difference in TV measurements for the same testis was seen in 25% (7 of 28) of intra-observer measurements and 35% (12 of 34) of interobserver measurements. These 20% differences were more common with a lower body mass index (odds ratio, OR=0.74, p=0.01) in the interobserver group, and lower TV was a predictor in the intra-observer group (OR: 0.82, p=0.009). Variability exists in both interobserver and intra-observer measurements of TV by dedicated urologic ultrasonographers, and greater than 20% of differences in measured TV in same testicles occurred in over 25% of cases. Caution should be exercised in basing operative decisions and scientific studies on limited measurements of TV.

A5707 Determinants and Regression Equations for the Calculation of Z-scores of Left Heart Structures in Healthy Han Chinese Adult

Objectives: Congenital and acquired heart disease remains reliant on detailed measurements of cardiac structures using two-dimensional echocardiography. Calculated Z-scores are often used to normalize these measurements in pediatric patients. However, the determinants of left heart structures in adults are rarely reported. We investigated the predictors of left heart (LH) structures in a healthy Chinese Han adult population and established normative data and regression equations for the calculation of Z-scores. Methods: Two-dimensional and M-mode echocardiography were performed in 604 patients ranging from 18 to 80 years old (age of 44.4 ± 13.6 years, 56.4% male and 43.6% female). Six routine left structural measurements (AOD, LAD, LVDd, LVDs, IVSTd, LVPWd) were determined. Data are presented graphically, and regression equations relating cardiac diameter to the most important determinants involved with calculation Z-scores are derived. Results: Body surface area (BSA) was the strongest determinant of left cardiac structures. (AOD r = 0.42 p < 0.001;LAD r = 0.43 p < 0.001;LVDd r = 0.69 p < 0.001;LVDs r = 0.56 p < 0.001;IVSd r = 0.32 p < 0.001;LVPWd r = 0.36 p < 0.001). BSA-specific reference ranges, regression equations, and scatterplots for the calculation of z scores were determined for each index. Conclusion: BSA is the strongest determinant of left heart structures in Chinese Han adults. The availability of BSA-specific normalized data for the calculation of Z-scores may be valuable for better detection of congenital and acquired heart disease.

The Levels of Bone Alkaline Phosphatase (BALP) and Soluble Epidermal Growth Factor Receptor-2 (ECD/HER-2) in Pediatric Patients with Osteosarcoma During Clinical Treatment

AimThe aim of this study was to assess the usefulness of bone-specific alkaline phosphatase (BALP) and the extracelluar domain of human epidermal growth factor receptor 2 (ECD/HER-2) measurements in pediatric patients with osteosarcoma as prospective prognostic and predictive markers for monitoring the treatment and early detection of disease recurrence.Material and methodsWe studied 22 patients (5 girls, 17 boys) aged 7-20 years with osteosarcoma (OS) treated at the Institute of Mother and Child in Warsaw. All the patients were evaluated for the serum levels of BALP and ECD/HER-2 before treatment, during pre- and postoperative chemotherapy and after the completion of treatment. Healthy children (n=22) were the reference group. The levels of BALP and ECD/HER-2 were measured using immunoenzymatic methods.ResultsThe values of BALP and ECD/HER-2 proteins were higher (p<0.01; p<0.05, respectively) in patients with osteosarcoma at the time of diagnosis compared with the control group. The values of both markers significantly decreased during chemotherapy in most patients with remission. In contrast to ECD/HER-2, the value of BALP after therapy was higher in patients with progression than with remission (p<0.001).ConclusionsOur results demonstrate the different pattern of BALP and ECD/HER-2 proteins during clinical treatment in patients with osteosarcoma. Higher values of BALP may characterize the progression of the disease and unfavourable prognosis. Further longitudinal studies are necessary to confirm the prognostic values of BALP and ECD/HER-2 proteins in this group of patients.

Vascular ultrasound in pediatrics: utility and application of location and measurement of jugular and femoral vessels.

To measure the depth (D p) and diameter (D m) of the internal jugular vein (IJV), femoral vein (FV), and femoral artery (FA) in pediatric patients to evaluate the clinical implications. This study included 125 pediatric patients. All of them underwent bilateral ultrasound study of vessels and were classified into three groups based on anthropometric and demographic parameters. Measured mean D p values were: 0.72 (0.34)cm for the FA, 0.79 (0.35)cm for the FV, and 0.77 (0.24)cm for the IJV. Mean antero-posterior D m values were: 0.37 (0.17)cm for the FA, 0.42 (0.22)cm for the FV, and 0.59 (0.23)cm for the IJV. D p and D m increased with age (A), weight (W), height (H), and body surface area (BSA). In the lower ranges of these variables, D p was similar for all three studied vessels (0.6-0.7cm). In the higher ranges, femoral vessel D p values (1.1-1.2cm) were larger than jugular ones (0.9cm). Additionally, in these low ranges, IJV D m values were larger than femoral ones (0.45-0.50 vs. 0.25cm). In the higher ranges, diameter values were similar (0.6-0.7cm). In pediatric patients, major vessels can be located and their depth and diameter measured by vascular ultrasound. In younger patients, jugular and femoral vessels had similar depth values; in older ones, they had similar diameters. Ultrasound measurements in pediatric patients could facilitate the choice of the vessel to be cannulated, the catheter diameter, and the length of the needle to be used. Vascular canalization of IJV may be recommended as the first choice because of its low depth and large diameter.

MRI measurements of the normal pediatric optic nerve pathway

The purpose of this work is to establish a reference scale of optic nerve pathway measurements in pediatric patients according to age using MRI. Optic nerve pathway measurements were retrospectively analyzed using an orbits equivalent sequence on brain MRI scans of 137 pediatric patients (72 male, 65 female, average age = 7.7 years, standard deviation = 5.3). The examinations were performed on a 1.5-T or 3-T Siemens MR system using routine imaging protocols. Measurements include diameters of the orbital optic nerves (OON), prechiasmatic optic nerves (PON), optic tracts (OT), and optic chiasm (OC). Measurements were performed manually by 2 neuroradiologists, using post-processing software. Patients were stratified into five age groups for measurement analyses: (I) 0–1.49 years, (II) 1.5–2.99 years, (III) 3–5.99 years, (IV) 6–11.99 years, and (V) 12–18 years. The observed value range of OON mean diameter was 2.7 mm (Interquartile range (IQR) = 2.4–2.9), PON was 3.2 mm (IQR = 3.05–3.5), OT 2.6 mm (IQR = 2–2.9). A strong positive correlation was established between age and mean diameter of OON (r = 0.73, p < .001), PON (r = 0.59, p < .001), and OT (r = 0.72, p < .001). A significant difference in mean OON diameters was found between age groups I–II (d = 0.3, p = .01), II–III (d = 0.5, p < .001), III–IV (d = 0.5, p < .001) followed by a plateau between IV-V (d = 0.l0, p = .19). OON/OT ratio maintained a steady mean value 1 (IQR = 0.93–1.1) regardless of age (p = .7). The diameter of optic pathways was found to increase as a function of age with consistent positive correlation between nerve and tract for all ages.

Assessment of the macula and choroid in pediatric keratoconus patients

PurposeTo present choroidal and macular thickness measurements in pediatric patients with keratoconus and to evaluate a possible correlation between anterior and posterior segment parameters. Methods50 eyes of 50 patients and 50 eyes of 50 age-matched controls were included in this cross-sectional comparative study. The participants underwent ophthalmologic examination including; refraction, visual acuity, biomicroscopy, corneal topography and optical coherence tomography. The choroidal thickness (CT) was measured at subfoveal area and at 500 microns intervals to the nasal and temporal to the fovea up to 1500 microns. ResultsThe mean age of the patients and controls were 12.4 ± 1.9 and 12.0 ± 2.1 years. The mean thinnest corneal pachimetry was 456 ± 57 μm, the mean central macular thickness (CMT) was 258 ± 24 μm and the mean subfoveal choroidal thickness was 342 ± 30 μm for the patients. There was no significant difference between the patients and controls in regards of CMT and CT at any measured points (p > 0.05 for all). There was no correlation between anterior segment parameters and CMT. There was no correlation between anterior segment parameters and subfoveal choroidal thickness. ConclusionsWe may conclude that keratoconus does not affect the CMT and CT of pediatric keratoconus patients, and we may propose that we do not need a correction for this group of patients when we need to evaluate the CMT and CT.

Reproducibility of Left Ventricular Dimension Versus Area Versus Volume Measurements in Pediatric Patients With Dilated Cardiomyopathy.

Multiple echocardiographic methods are used to measure left ventricular size and function. Clinical management is based on individual evaluations and longitudinal trends. The Pediatric Heart Network VVV study (Ventricular Volume Variability) in pediatric patients with dilated cardiomyopathy has reported reproducibility of several of these measures, and how disease state and number of beats impact their reproducibility. In this study, we investigated the impact of observer and sonographer variation on reproducibility of dimension, area, and volume methods to determine the best method for both individual and sequential evaluations. In 8 centers, echocardiograms were obtained on 169 patients prospectively. During the same visit, 2 different sonographers acquired the same imaging protocol on each patient. Each acquisition was analyzed by 2 different observers; first observer analyzed the first acquisition twice. Intraobserver, interobserver, interacquisition, and interobserver-acquisition (different observers and different acquisition) reproducibility were assessed on measurements of left ventricular end-diastolic dimension, area, and volume. Left ventricular shortening fraction, ejection fraction, mass, and fractional area change were calculated. Percent difference was calculated as (interobservation difference/mean)×100. Interobserver reproducibility for both acquisitions was better for both volume and dimension measurements (P≤0.002) compared with area measurements, whereas intraobserver, interacquisition (for both observers), and interobserver-acquisition reproducibilities (for both observer-acquisition sets) were best for volume measurements (P≤0.01). Overall, interobserver-acquisition percent differences were significantly higher than interobserver and interacquisition percent differences (P<0.001). In pediatric patients with dilated cardiomyopathy, compared with dimension and area methods, left ventricular measurements by volume method have the best reproducibility in settings where assessment is not performed by the same personnel. URL: https://www.clinicaltrials.gov. Unique identifier: NCT00123071.

Measurements in Pediatric Patients with Cardiomyopathies: Comparison of Cardiac Magnetic Resonance Imaging and Echocardiography

Aims: Cardiomyopathies are common cardiovascular diseases in children. Cardiac magnetic resonance imaging (cMRI) and echocardiography (Echo) are routinely applied in the detection and diagnosis of pediatric cardiomyopathies. In this study, we compared and explored the correlation between these two measurements in pediatric patients with various cardiomyopathies. Methods and Results: A total of 53 pediatric patients with cardiomyopathy hospitalized during the recent 3 years in our hospital were analyzed. All of them and 22 normal controls were assessed by both cMRI and Echo. Cardiac function of the patients was graded according to the New York Heart Association functional classification. The cardiac function indexes measured with both cMRI and Echo included left-ventricular (LV) end-diastolic volume (EDV), end-systolic volume, ejection fraction and fractional shortening. These parameters were somehow lower in cMRI measurements than in Echo measurements. The index of diastolic function, such as peak filling rate (PFR) measured with cMRI, had a good correlation with the clinical cardiac functional score, while the index of the diastolic function (early/atrial filling ratio and isovolumic relaxation time) measured with Echo was not well correlated with the clinical cardiac function score. Significant systolic dysfunction was detected by cMRI in 34 patients with dilated cardiomyopathy, LV noncompaction or endocardial fibroelastosis. Significant diastolic dysfunction was detected by cMRI in 19 patients with hypertrophic cardiomyopathy or restrictive cardiomyopathy showing an alteration in PFR and EDV. Conclusion: Both cMRI and Echo are of great value in the diagnosis and assessment of cardiac function in pediatric patients with cardiomyopathy. cMRI could accurately display the characteristic morphological changes in the hearts affected with cardiomyopathies, and late gadolinium enhancement on cMRI may reveal myocardial fibrosis, which has obvious advantages over Echo measurements in diagnosis. Furthermore, cMRI can quantitatively determine ventricular function because it does not make invalid geometrical assumptions.

153 What are the Sonographic Baseline Measurements of the Inferior Vena Cava Diameter in Normovolemic Children?

Children who present with dehydration or sepsis account for a significant number of pediatric emergency department visits. Accurate and rapid assessment of intravascular volume status is vital to providing appropriate management. Adult studies have demonstrated that point-of-care ultrasound of the inferior vena cava (IVC) can provide a rapid and objective measurement of a patient’s intravascular volume status. However, there is a lack of reference values for IVC diameter measurements in pediatric patients. Previous studies report the patient’s dry weight, IVC/body surface area ratio, IVC/aorta ratio, or collapsibility index as reference standards for pediatric IVC measurements. There are no definitive studies to date evaluating baseline IVC diameters in healthy children with presumed normal intravascular volume. To evaluate normative baseline sonographic measurements of the IVC diameter in healthy pediatric patients. This was a prospective observational study of a convenience sample of healthy patients between ages 0 and 22 presenting to a single institution pediatric emergency department. Exclusion criteria included abnormal vital signs, pregnancy, or illnesses thought to influence volume status (eg, diarrhea, vomiting, and asthma). Point-of-care ultrasound was performed on supine patients in the subxiphoid area using the phased array transducer of a SonoSite Edge machine. During quiet respiration, the maximal and minimal IVC diameters were measured in the sagittal plane distal to where the hepatic vein joins the IVC. As a second measurement, the maximal diameters of the IVC and aorta were measured in the transverse plane distal to the insertion of the left renal vein into the IVC. The institutional review board approved this study. From February 2013 through April 2014, sixty-three children (50.8% female, mean age 10.5 years) were enrolled. There were twenty children in each age group 2-7 years, 7-12 years, and 12-22 years. Children less than two years old had difficulty tolerating the examination and commonly presented with chief complaints and/or vital signs which met exclusion criteria. Consequently, fewer patients were enrolled in the less-than-two-years age group. The correlation between IVC and aorta diameters as a function of age were calculated using the Spearman’s rank correlation coefficient. The correlation coefficients were all statistically significant (P<.001): maximum IVC diameter sagittal plane (0.81), minimum IVC diameter sagittal plane (0.79), maximum IVC diameter transverse plane (0.79), maximum aorta diameter transverse plane (0.81). We present a pilot study of the sonographic measurements of the IVC diameter in normovolemic children. A statistically significant positive correlation was found between age and IVC diameter. Future studies should focus on multi-center enrollment, children in the youngest age group, and the development of normative growth curves of the IVC by age, sex, and body mass index.

Quantitative MRI for hepatic fat fraction and T2* measurement in pediatric patients with non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children. The gold standard for diagnosis is liver biopsy. MRI is a non-invasive imaging method to provide quantitative measurement of hepatic fat content. The methodology is particularly appealing for the pediatric population because of its rapidity and radiation-free imaging techniques. To develop a multi-point Dixon MRI method with multi-interference models (multi-fat-peak modeling and bi-exponential T2* correction) for accurate hepatic fat fraction (FF) and T2* measurements in pediatric patients with NAFLD. A phantom study was first performed to validate the accuracy of the MRI fat fraction measurement by comparing it with the chemical fat composition of the ex-vivo pork liver-fat homogenate. The most accurate model determined from the phantom study was used for fat fraction and T2* measurements in 52 children and young adults referred from the pediatric hepatology clinic with suspected or identified NAFLD. Separate T2* values of water (T2*W) and fat (T2*F) components derived from the bi-exponential fitting were evaluated and plotted as a function of fat fraction. In ten patients undergoing liver biopsy, we compared histological analysis of liver fat fraction with MRI fat fraction. In the phantom study the 6-point Dixon with 5-fat-peak, bi-exponential T2* modeling demonstrated the best precision and accuracy in fat fraction measurements compared with other methods. This model was further calibrated with chemical fat fraction and applied in patients, where similar patterns were observed as in the phantom study that conventional 2-point and 3-point Dixon methods underestimated fat fraction compared to the calibrated 6-point 5-fat-peak bi-exponential model (P < 0.0001). With increasing fat fraction, T2*W (27.9 ± 3.5ms) decreased, whereas T2*F (20.3 ± 5.5ms) increased; and T2*W and T2*F became increasingly more similar when fat fraction was higher than 15-20%. Histological fat fraction measurements in ten patients were highly correlated with calibrated MRI fat fraction measurements (Pearson correlation coefficient r = 0.90 with P = 0.0004). Liver MRI using multi-point Dixon with multi-fat-peak and bi-exponential T2* modeling provided accurate fat quantification in children and young adults with non-alcoholic fatty liver disease and may be used to screen at-risk or affected individuals and to monitor disease progress noninvasively.

Correlations between B-type natriuretic peptide levels and nongeometric echocardiographic parameters in pediatric cardiomyopathies

B-type natriuretic peptide is a conventional cardiac biomarker in adult cardiology, however, it is not commonly used in pediatric cases. After introducing B-type natriuretic peptide measurements in pediatric patients for the evaluation of systemic right ventricular function, the authors wanted to evaluate the value of plasma B-type natriuretic peptide and compare the results with systolic and diastolic myocardial parameters obtained with conventional echocardiography and tissue Doppler imaging in children with cardiomyopathy. Between 2007 and 2010, 58 plasma B-type natriuretic peptide measurements were performed in 32 children (dilated cardiomyopathy in 20, hypertrophic cardiomyopathy in 10 and non-compacted cardiomyopathy in 2 cases). The age of the patients was 7.9±6.6 years (mean±SD). Plasma B-type natriuretic peptide was measured using an electrochemiluminescent assay within one day from echocardiographic evaluation. As compared to normal values, children with the 3 types of cardiomyopathies showed significant differences in plasma B-type natriutretic peptide levels (dilated cardiomyopathy vs normal, p<0.001; hypertrophic cardiomyopathy vs. normal, p<0.01; non-compacted cardiomyopathy vs. normal, p<0.001). There was a significant negative correlation (r = -0,63; p<0,01) between B-type natriuretic peptide levels (range, 12-7002 ng/L; mean±SD, 1531±1750 ng/L) and linEF values (range, 4-50%; mean±SD, 22.5±13%). For B-type natriuteric peptide, a cut-off point of 1000 ng/L proved to differentiate significantly decreased linEF values (<17%). B-type natriuretic peptide levels significantly correlated with left ventricular end-diastolic diameter (r = 0.899; p<0.001), with left ventricular anular S wave parameters (r = 0.689; p<0.001) and with E/e ratio (r = 0.43; p<0.05). B-type natriuretic peptide measurements are recommended in all types of cardiomyopathies.

Correlation of a Novel Noninvasive Tissue Oxygen Saturation Monitor to Serum Central Venous Oxygen Saturation in Pediatric Patients with Postoperative Congenital Cyanotic Heart Disease

Using a novel noninvasive, visible-light optical diffusion oximeter (T-Stat VLS Tissue Oximeter; Spectros Corporation, Portola Valley, CA) to measure the tissue oxygen saturation (StO2) of the buccal mucosa, the correlation between StO2 and central venous oxygen saturation (ScvO2) was examined in children with congenital cyanotic heart disease undergoing a cardiac surgical procedure. Paired StO2 and serum ScvO2 measurements were obtained postoperatively and statistically analyzed for agreement and association. Thirteen children (nine male) participated in the study (age range, 4 days to 18 months). Surgeries included Glenn shunt procedures, Norwood procedures, unifocalization procedures with Blalock-Taussig shunt placement, a Kawashima/Glenn shunt procedure, a Blalock-Taussig shunt placement, and a modified Norwood procedure. A total of 45 paired StO2-ScvO2 measurements was obtained. Linear regression demonstrated a Pearson’s correlation of .58 (95% confidence interval [CI], .35–.75; p &lt; .0001). The regression slope coefficient estimate was .95 (95% CI, .54–1.36) with an interclass correlation coefficient of .48 (95% CI, .22–.68). Below a clinically relevant average ScvO2 value, a receiver operator characteristic analysis yielded an area under the curve of .78. Statistical methods to control for repeatedly measuring the same subjects produced similar results. This study shows a moderate relationship and agreement between StO2 and ScvO2 measurements in pediatric patients with a history of congenital cyanotic heart disease undergoing a cardiac surgical procedure. This real-time monitoring device can act as a valuable adjunct to standard noninvasive monitoring in which serum ScvO2 sampling currently assists in the diagnosis of low cardiac output after pediatric cardiac surgery.