Normative Reference Data Research Articles

Quality-Adjusted Life Expectancy Norms Based on the EQ-5D-5L and SF-6Dv2 for China.

Quality-adjusted life expectancy (QALE) norms reflect the normative profiles or reference data of QALE of the general population and provide a meaningful anchor for comparison to inform healthcare decision-making. This study aimed to develop the QALE norms for the Chinese population by using a representative dataset of health utility values collected using the EQ-5D-5L and short-form 6-dimension version 2 (SF-6Dv2) instruments. Age-specific population norms of health utility values calculated using the EQ-5D-5L and SF-6Dv2 were used. Both utility norms were combined with the latest version of the National Life Tables of China published in 2021 to calculate QALE estimates on the basis of age, sex, and urban/rural residence area. QALE estimates were further discounted using 1.5%, 3.5%, 5.0%, and 8.0% discount rates. When using the health utility values evaluated by the SF-6Dv2, the QALE at age 0 years was 66.34 years at the discount rate of 0% and 16.65 years at the discount rate of 5%. For the EQ-5D-5L, the QALE at age 0 years was 76.50 years at the discount rate of 0% and 19.45 years at the discount rate of 5%. At birth, females exhibited a higher QALE, while the difference between females and males initially increased before subsequently declining overtime, ultimately resulting in females having a lower QALE. Rural population had a monotonically lower QALE than urban population. This study constructed age-stratified QALE norms for the Chinese population categorized by sex and residence area using mortality data alongside corresponding health utility values derived from the EQ-5D-5L and SF-6Dv2.

The Impact of Vocal Tremor on Deglutition: A Pilot Study.

Vocal tremor (VT) poses treatment challenges due to uncertain pathophysiology. VT is typically classified into two phenotypes: isolated vocal tremor (iVT) and essential tremor-related voice tremor (ETvt). The impact of phenotypes on upper aerodigestive tract physiology during swallowing remains unclear. Qualitative and quantitative measures were employed to characterize tremor phenotypes and investigate the effects on swallowing physiology. Eleven ETvt participants (1 Male, 10 Female; x̄ age = 74) and 8 iVT participants (1 Male, 7 Female; x̄ age = 71) swallowed 20 mL boluses in cued and uncued conditions under standardized fluoroscopic visualization. Sustained/a/productions were captured to assess the rate and extent of fundamental frequency (F0) modulation. Penetration and Aspiration Scale (PAS) scores were obtained and swallowing biomechanics were captured using Swallowtail™ software. Participants also completed the Swallowing Quality of Life (SWAL-QOL) questionnaire. Hypopharyngeal transit was faster in both VT phenotypes compared with Swallowtail™ normative reference data. Total pharyngeal transit times, however, were only faster in patients with iVT, relative to reference data. No significant differences were observed on the SWAL-QOL or PAS between tremor phenotypes. SWAL-QOL scores revealed that these patients rarely reported dysphagia symptoms. Subtle differences in swallowing patterns were observed across VT phenotypes, possibly related to adaptive mechanisms resulting in quicker pharyngeal bolus transit. Most patients did not report swallowing issues or dysphagia symptoms. This study is foundational for larger studies on this challenging population. 4 Laryngoscope, 134:4599-4603, 2024.

Normative data on measures of cardiovascular autonomic neuropathy and the effect of pretest conditions in a large Danish non-diabetic CVD-free population from the Lolland-Falster Health Study.

Cardiovascular autonomic neuropathy (CAN) is a common diabetic complication associated with excess morbidity and mortality. CAN is also seen in conditions such as Parkinson's disease. Normative reference data for cardiovascular autonomic function are used to stratify individuals into those with and without CAN. However, reference thresholds for both cardiovascular autonomic reflex tests (CARTs) and heart rate variability (HRV) are scarce and based on small sample sizes. The aim of the study was to establish contemporary normative reference thresholds based on a large non-diabetic population free of cardiovascular disease (CVD). Cardiovascular autonomic function, CARTs and 5-min HRV indices were assessed in individuals without diabetes and CVD from the Lolland-Falster Health Study (2018-2020) by applying the point-of-care device Vagus™. Age-specific normative reference thresholds were estimated by using log-transformed quantile regression models at the 5th and 10th percentile, with adjustments made for sex. Models assessing the association between age and HRV indices were further adjusted for heart rate. We present age-specific normative reference thresholds for cardiovascular autonomic function, including CARTs and HRV, for 875 individuals (48% females) aged 15-85years. The reference thresholds are presented for both the 5th and 10th lower percentile. Higher age was inversely associated with all outcomes. Females tended to have a higher parasympathetic drive compared to males. Pre-test conditions did not affect CARTs significantly. The presented age-related normative reference thresholds for both CARTs and HRV indices based on a large Danish cohort may facilitate improved quality of research and treatment.

Preliminary Normative Reference Values of Validated FEES Scales in Healthy Young Adults.

Limited normative reference data are available for validated outcomes of flexible endoscopic evaluation of swallowing (FEES). We aimed to examine healthy swallowing via FEES in community-dwelling healthy adults to derive a preliminary reference dataset of normative validated FEES outcomes to guide clinical interpretation and diagnostic decision-making. Adults with no history of dysphagia-related disease underwent simultaneous videofluoroscopy and FEES imaging using a standardized 11-item bolus protocol. Trained raters performed duplicate, independent, blinded ratings of the New Zealand Secretion Scale (NZSS), Penetration-Aspiration Scale (PAS), and Dynamic Imaging Grade of Swallowing Toxicity-FEES (DIGEST-FEES) validated scales. Descriptive statistics were performed at the bolus (PAS) and participant level (NZSS, DIGEST-FEES). 361 swallows from 33 community-dwelling adults (36.6 ± 14.7 years old) were analyzed. In rank order, distribution profiles were: (1) NZSS: 95% normal (NZSS = 0), 5% abnormal (NZSS = 4); (2) Worst PAS: 73% safe (PAS 1-2, n = 24), 21% penetration above the true vocal folds (PAS 3, n = 7), 6% deep penetration to the true vocal folds (PAS = 5, n = 2); (3) DIGEST-FEES Safety Grades: 91% Grade 0 (normal, n = 30), 9% Grade 1 (mild impairment, n = 3); (4) DIGEST-FEES Efficiency Grades: 73% Grade 0 (normal, n = 24), 24% Grade 1 (mild impairment, n = 8), 3% Grade 2 (moderate impairment, n = 1). This preliminary healthy FEES dataset highlights variation in swallowing safety and efficiency and suggests careful interpretation of FEES outcomes to avoid over-pathologizing impairment. Future studies are warranted to obtain additional normative data in diverse populations to further understand normal variation in FEES outcomes to guide clinically meaningful diagnostic cut-points. Level 3 Laryngoscope, 2024.

The Enduring Challenge of Literacy Issues in Adulthood: Investigating Spelling Deficits among Dyslexic Italian University Students.

The issue of literacy challenges among dyslexic adults remains a significant concern. This study investigates spelling deficits among highly educated adults with dyslexia learning a transparent orthography. Thirty-eight Italian dyslexic university students were examined and compared to a group of age- and education-matched typical readers. Firstly, we analyzed spelling performance using a Passage Dictation Test. Additionally, lists of words varying in length and word frequency were dictated under two experimental conditions: a normal condition (NC) and an articulatory suppression condition (ASC). The ASC assessed the participants' ability to spell with interference to the phonological (sublexical) spelling procedure, i.e., the most likely compensated spelling strategy of Italian dyslexic spellers. The results clearly indicated that, in spelling the meaningful passage, dyslexic participants underperformed compared to the controls, with a prevalence of lexical errors, despite the comparison with the normative reference data showing only mild spelling difficulties. In spelling isolated words in normal conditions, dyslexic participants performed within the reference norms and as accurately as control participants across all stimuli (short words, high- and low-frequency words), except for long words, where their spelling difficulties were evident. Articulatory suppression significantly impaired dyslexics' performance on short stimuli, reducing the usual sublexical advantage associated with them, and exacerbated misspellings on long words. Additionally, articulatory suppression disproportionately affected dyslexics' performance on high-frequency words, diminishing the typical lexical advantage associated with these words. Results are discussed in terms of their theoretical, clinical, and educational implications.

Age-adjusted CSF t-tau and NfL do not improve diagnostic accuracy for prodromal Alzheimer’s disease

Cerebrospinal fluid total-tau (t-tau) and neurofilament light chain (NfL) are biomarkers of neurodegeneration and are increased in Alzheimer’s disease (AD). In order to adjust for age-related increases in t-tau and NfL, cross-sectional age-adjusted norms were developed based on amyloid negative cognitively normal (CN) adults aged 41–78 years (CN, n = 137). The age-adjusted norms for t-tau and NfL did not improve receiver operating curve based diagnostic accuracies in individuals with mild cognitive impairment (MCI) due to AD (AD-MCI, n = 144). Furthermore, while NfL was correlated with higher age in AD-MCI, no significant correlation was found for t-tau. The cox proportional hazard models, applied in 429 participants with baseline t-tau and NfL, showed higher hazard ratio of progression to MCI or dementia without age-adjustments (HR = 3.39 for t-tau and HR = 3.17 for NfL), as compared to using our norms (HR = 2.29 for t-tau and HR = 1.89 for NfL). Our results indicate that utilizing normative reference data could obscure significant age-related increases in these markers associated with neurodegeneration and AD leading to a potential loss of overall diagnostic accuracy.

The prediction of estimated cerebral perfusion pressure with trans-systolic time in preterm and term infants.

It is important to monitor cerebral perfusion in infants because hypo- and hyperperfusion can contribute to neurological injury. This study aimed to clarify the relationship between trans-systolic time (TST) and critical closing pressure (CrCP) or estimated cerebral perfusion pressure (CPPe) in neonates. Moreover, we aimed to determine the TST values in preterm and term infants with stable cerebral perfusion to clarify normative reference data. This multicentre prospective study included infants with arterial lines admitted to the neonatal intensive care units between December 2021 and August 2023. TST, CrCP, and CPPe were calculated using middle cerebral artery waveforms recorded using transcranial Doppler ultrasonography when clinicians collected arterial blood samples. Three hundred and sixty samples were obtained from 112 infants with a gestational age of 32 (interquartile range, 27-37) weeks and a birth weight of 1481 (956-2355) g. TST was positively correlated with CPPe (r = 0.60, p < 0.001), but not with CrCP (r = 0.08, p = 0.10). The normative reference values of TST in preterm and term infants without samples of hyper- or hypocapnia and/or hyper- or hypotension, which may affect cerebral perfusion, were as follows: ≤ 29weeks, 0.12 (0.11-0.14) s; 30-36weeks, 0.14 (0.12-0.15) s; and ≥ 37weeks, 0.16 (0.14-0.17) s, respectively. Conclusion: TST in neonates significantly correlated with CPPe, but not with CrCP. TST may be a good predictor of cerebral perfusion and potentially have wider clinical applications. What is Known: •Trans-systolic time (TST) is used in evaluating the effects of increased intracranial pressure on cerebral haemodynamics. However, little is known about the efficacy of TST in predicting neonatal cerebral perfusion pressure. What is New: •This study added evidence that TST correlated with estimated cerebral perfusion pressure, but not with critical closing pressure. Additionally, we showed the normative reference values of the TST in preterm and term infants.

Normative reference data for intracranial volume in children: The results of CT volumetry.

Intracranial volume (ICV) is an important indicator of the development of the brain and skull in children. At present, there is a lack of ICV growth standards based on large infant and children samples. Our aim was to assess the normal range of the ICV variation in Russian children using a modern automatic system for constructing the endocranial cavity (Endex) and to provide growth standards of the ICV for clinical practice. High-resolution head CT scans were obtained from 673 apparently healthy children (380 boys and 293 girls) aged 0-17years and transformed into the ICV estimates using the Endex software. The open-source software RefCurv utilizing R and the GAMLSS add-on package with the LMS method was then used for the construction of smooth centile growth references for ICV according to age and sex. We demonstrated that the ICVs estimates calculated using the Endex software are perfectly comparable with those obtained by a conventional technique (i.e. seed feeling). Sex-specific pediatric growth charts for ICV were constructed. This study makes available for use in clinical practice ICV growth charts for the age from 0 to 17 based on a sample of 673 high-resolution CT images.

The Sport Concussion Assessment Tool: A multidimensional symptom model for detecting elevated post-concussion symptoms

Objective: Investigate whether a four-factor model of post-concussion symptoms (i.e. cognitive, physical, affective, and sleep-arousal) aids in identifying student-athletes with persistent concerns not reflected by a total symptom score. Method: Collegiate student-athletes (N = 32,066) from the Concussion Assessment Research and Education consortium completed the Sport Concussion Assessment Tool, 3rd edition Symptom Evaluation at baseline and two post-injury follow-ups (i.e. beginning RTP and 6-month). Confirmatory factor analysis was used to compare a one- and four-factor model of post-concussion symptoms. Normative reference data were compared across stratifications (e.g. sex, prior concussions, and number of pre-existing conditions) using Mann-Whitney U tests, and elevation rates (i.e. ≥ 84th percentile) for subscales and the total score were recorded. Results: The four-factor model fit well before and after injury (CFIs > .95). Greater symptom severity on the subscale and total scores was associated with female sex (ps<.001, r range: .07 to .14) and more pre-existing conditions (ps<.001, η 2 range: .01 to .04), while having more prior concussions was only related to total symptom scores (ps<.001, η 2<.01). After a concussion, a sizeable portion of student-athletes (i.e., RTP = 11.8%; 6-month = 8.3%) had subscale elevations despite no total score elevation. Physical subscale elevations at RTP were the most common (i.e., 11.9%), driven by head and neck pain. Conclusion: After a sport-related concussion, a four-factor symptom model can be used to assess persistent symptoms in collegiate student-athletes. Identifying athletes with domain-specific elevations may help clinicians identify areas for further assessment and, in some cases, personalized rehabilitation plans.

A - 144 Prior Concussions and Symptom Elevation Rates in Collegiate Student-Athletes at Preseason Baseline.

Assess how prior concussions are related to baseline symptom endorsement using a four-factor model of post-concussion symptoms (i.e., cognitive, sleep-arousal, physical, and affective). Athletes from the Concussion Assessment, Research, and Education consortium (N&#3f7,370; 64% Male; 62% White; 36% Freshmen; 15% Football players) with at least one prior concussion were administered the Sport Concussion Assessment Tool-3 Symptom Evaluation at baseline. Subscale and total scores ≥84th percentile were considered elevated based on normative reference data from uninjured participants matched on gender and number of preexisting conditions. The symptoms of Headache, Pressure in head, Sensitivity to light, and Difficulty remembering were endorsed at a significantly higher rate (ps < 0.001, OR range = 1.35 to 1.40) by those with two or more prior concussions compared to those with one prior concussion. Approximately 22% of athletes had an elevated subscale score without an elevated total score. In contrast, no athletes were elevated on the total score without also being elevated on a subscale score, and 18% of athletes were elevated on both a subscale and the total score. The physical subscale was consistently the most frequent exclusively elevated subscale in the full sample (cognitive = 4%; physical = 10%, sleep-arousal = 6%, affective = 7%). Prior concussion status is related to item-level symptom endorsement among collegiate athletes at preseason baseline. A multidimensional approach to symptom interpretation identified a sizeable number of athletes (i.e., 22%) with significant symptoms that were not captured by a total score elevation. Most athletes with an elevated subscale score (i.e., 55%) were experiencing physical symptoms.

OR30-03 High Resolution Daily Profiles Of Tissue Adrenal Steroids By Portable Automated Collection

Abstract Disclosure: T. Upton: None. E. Zavala: None. P. Methlie: None. M. Oksnes: None. M.A. Grytaas: None. K. Simunkova: None. S. Bensing: None. I. Botusan: None. K. Berinder: None. D.A. Vassiliadi: None. O. Kampe: None. S. Tsagarakis: None. E.S. Husebye: None. G.M. Russell: None. S.L. Lightman: None. Background: Rhythms are intrinsic to endocrine systems, and disruption of these hormone oscillations occurs at very early stages of disease. Since adrenal hormones are secreted with both circadian and ultradian periods, conventional single time point measures provide limited information about rhythmicity, and crucially do not provide information during sleep when many hormones fluctuate from nadir to peak concentrations. If blood sampling is attempted overnight this necessitates admission to a clinical research unit, can be stressful and disturbs normal sleep. Aim: To obtain automated ambulatory 24-hour profiles of adrenal steroids in healthy human subcutaneous tissue to characterize healthy variability without blood sampling. Methods: We used microdialysis, an ambulatory fraction collector and liquid-chromatography mass-spectrometry to obtain 72-point profiles of tissue free adrenal steroids over 24 hours in n=214 healthy volunteers. For validation, we compared tissue against plasma measurements in n=7 inpatient healthy volunteers. We used stationery statistics, time series analyses, and mathematical methods to characterise interindividual and intraindividual variability of these hormones at different times of the day. Results: There were no serious adverse events, and the method was well tolerated, allowing almost all normal activities to continue. In addition to cortisol, we identified daily and ultradian variation in free cortisone, corticosterone, 18-OHF, aldosterone, THF, and aTHF. Rhythmic hormones were highly correlated when measured across the day, especially cortisol with 18OHF (rs = 0.99), cortisol with cortisone (rs = 0.96) and cortisol and 18-OHF with corticosterone (rs = 0.96-0.97). There was a very strong correlation between mean values of cortisol and 18OHF with aldosterone (rs = 0.91-0.93), but aldosterone profiles were characterized by high interindividual variability. Tissue 18-OHF was the most highly correlated with plasma cortisol (rs 0.89, range 0.74—0.97, p&amp;lt;0.001), and 18-OHF phase was advanced with respect to tissue cortisol. The ratio of tissue cortisol:cortisone exhibited a stronger daily rhythm than in plasma, with cortisol concentrations often falling below cortisone in the late afternoon and early part of sleep.Using the data, we computed mathematically defined metrics (“dynamic biomarkers”) stratified by sex, age, and BMI to quantify individual variability of hormone rhythms. Provisional analysis suggests no evidence for an effect of sex on cortisol or 18OHF, but evidence for a small effect of BMI on total 24-hour cortisol, 18OHF, corticosterone, and aldosterone. Conclusions: These data provide, for the first time, an insight into the dynamics of adrenal steroids in tissue in real world setting and will serve normative reference data for establishing novel and improved biomarkers of endocrine disease. Presentation: Sunday, June 18, 2023

The six spot step test is superior in detecting walking capacity impairments compared to short- and long-distance walk tests in persons with multiple sclerosis.

Walking capacity is important not only to persons with multiple sclerosis but also to clinical practice and research. The present study aims to compare the extent of impairments (relative to healthy controls) across three commonly used walking capacity outcomes in persons with multiple sclerosis. In a two-hospital cross-sectional study, walking capacity was assessed using the timed-25-footwalk-test (timed 25-ft walk test; 'walking speed'), the six-minute-walk-test ('walking endurance') and the six-spot-step-test ('walking balance and coordination'). Data were compared to normative reference data in healthy controls. A total of 228 persons with multiple sclerosis (68% females) were involved in the study: age 53.7 ± 11.6 y (range 26-81 y); patient-determined-disease-steps 3 [IQR; 1; 4] (range 0-7); time since diagnosis 12.6 ± 9.9 y (range 0-49 y); MS-phenotype (relapse remitting MS, secondary progressive MS, primary progressive MS) 146/39/41; and co-morbidity n = 80 (35%). Compared to healthy controls, deficits were observed across all walking capacity outcomes (p < 0.001): timed 25-foot walk test -26 [-30; -23]%, 6 minute-walk-test -36 [-39; -32]% and six-spot-step-test -44 [-47; -40]%. Deficits differed across walking capacity outcomes (p < 0.001). Altogether, persons with multiple sclerosis performed substantially worse than healthy controls across all three walking capacity outcomes. The results showed that the six-spot-step-test was superior to the timed 25-foot walk test and the 6 minute-walk-test in detecting walking capacity impairments in persons with multiple sclerosis.

A-31 Normative Data For Cognitive, Physical, Affective, And Sleep-Arousal Symptom Subscales Of The SCAT-3 Symptom Evaluation

Abstract Purpose Develop baseline normative reference data for the Sport Concussion Assessment Tool-3 (SCAT-3) Symptom Evaluation and examine how sex and preexisting conditions relate to the symptom domains endorsed by collegiate athletes. Methods Participants (N=24,696 collegiate student-athletes; 62.6% Male, 61.5% White, 9.2% Hispanic or Latino) from the Concussion Assessment, Research, and Education Consortium completed the SCAT-3 at a preseason baseline. Using a four-factor model (i.e., cognitive, physical, affective, and sleep-arousal), normative percentiles were calculated for each symptom subscale and the total score, with stratifications by sex and number of preexisting conditions. Symptom score distributions were compared across stratifications using Mann-Whitney U tests. Results Generally, female athletes and those with more preexisting conditions endorsed significantly higher symptoms at baseline (e.g., 84th percentile affective score: males=1, females=3, p&amp;lt;.001, r=.14; females with 1 condition=4, 3+ conditions=8, p&amp;lt;.001, r=11; males with 1 condition=3, 3+ conditions=7, p&amp;lt;.01, r=.06). This pattern held for all but the physical (i.e., no difference between individuals with 1 and 3+ conditions) and sleep-arousal (i.e., no difference between males with 1 and 3+ conditions) subscales. Conclusions Female sex and preexisting conditions were associated with higher symptom burden on most subscales. A female athlete with a symptom score of 10 may appear to have elevated post-concussion symptoms; however, if she has 3 preexisting conditions, this experience is average (i.e., 50th percentile) compared to others with 3+ conditions at baseline. She may benefit from intervention, but symptoms may not be attributable to a concussion. Normative reference data may help indicate symptom severity when baseline data are unavailable.

Normative dataset selection affects gait profile scores of children with cerebral palsy

IntroductionThe Gait Profile Score (GPS) requires a comparative dataset, to identify altered mechanics in persons with a gait abnormality. This gait index has been shown to be useful for identifying gait pathology prior to the assessment of treatment outcomes. Though studies have shown differences in kinematic normative datasets between different testing sites, there is limited information available on the changes in GPS score based on normative dataset selection. The aim of this study was to quantify the influence of normative reference data from two institutions, on the GPS and Gait Variable Scores (GVS), calculated on the same group of patients with Cerebral Palsy. MethodsSeventy patients (Avg. age: 12.1 ± 2.9) diagnosed with CP underwent gait analysis during walking at a self-selected speed at Scottish Rite for Children (SRC). GPS and GVS scores were determined using normative kinematic data at a self-selected speed from, 83 typically developing children ages 4–17 from Gillette, and the same age range of children from SRC’s normative dataset. Average normalized speed was compared between institutions. Signed rank tests were performed on the GPS and GVS scores using each institution’s dataset. Spearman’s correlations between scores using SRC and Gillette were determined within GMFCS level. ResultsNormalized speed was comparable between each institution’s datasets. Within each GMFCS level, significant differences when using SRC vs. Gillette were found in most scores (p < 0.05). Scores were moderately to strongly correlated within each GMFCS level (range ρ = 0.448–0.998). ConclusionsSignificant statistical differences were found in GPS and GVS scores but were within the range of previously reported variation across multiple sites. Caution and consideration may need to be taken when reporting GPS and GVS scores that are calculated utilizing different normative datasets as these scores may not be equivalent.

Ground reaction forces, temporospatial parameters, range of motion, and limb characteristics were analyzed for small and medium size sound dogs with the use of pressure sensitive walkway.

To study ground reaction forces (GRF) and temporospatial parameters for small and medium size dogs using a pressure sensitive walkway (PSW). We hypothesized that, at a given speed, small dogs would have shorter stance time than medium dogs and that dog height (DH) would influence GRF. 30 healthy, sound dogs were divided into 2 groups, small < 15 kg and medium dog group weighing 15 to 25 kg. GRFs were measured for both groups at walk and trot using PSW. Muscle mass and joint angles were measured. Data were analyzed using SAS version 9.4. Two groups were compared using 2-sample t test, Wilcoxon rank sum test, and Fisher exact test. GRFs were successfully measured in both dog groups for walk and trot. Medium dogs had larger limb girth, more peak pressure, max force, increased stance, swing time, and larger stride length compared with small dogs. Stance time increased as DH increased at walk and trot (r = 0.854, P < .001; r = 0.876, P < .001). Stance time increased as BW (body weight) increased at walk and trot (r = 0.887, P < .001; r = 0.858 P < .001). Inconclusive data was obtained for stride acceleration and velocity. The handler side did not influence results (P > .05). Range of motion (ROM) did not differ among groups. Results suggested that PSW is a reliable device for small and medium dogs. At walk and at a trot, GRF are smaller in small dogs compared with medium dogs, suggesting that normal reference data for PSW need to take BW and DH into account.

Determining Biventricular Repair Feasibility in Children with Dominant Right Ventricle Using Left Ventricular Quality Measured on Cardiac Computed Tomography.

Left-ventricular (LV) characteristic measurements are crucial for evaluating the feasibility of biventricular repair (BiVR). This study aimed to determine the threshold of LV quality on cardiac computed tomography (CCT) for BiVR in children with a dominant right ventricle (DRV). We retrospectively reviewed all children with a DRV who underwent either BiVR or single ventricle palliation (SVP) at our institution between 2003 and 2019 in a case-control study with healthy individuals. Measurements including LV end-diastolic volume (LVEDV, mL), LV myocardial mass (LVMM, gm), and mitral annulus area (MAA, ) were quantified using CCT. The factor with the highest correlation with body size was used to adjust these three measurements to derive normal references in the control group. The LV quality of patients on each CCT measurement was represented as a percentage of the normal reference data that we established. The feasible LV quality for BiVR was defined as the lowest limit of all three LV measurements in one subject who survived BiVR among our patients with DRVs. The cohort comprised 30 patients and 76 healthy controls. Height was the factor with the highest correlation with all three LV measurements. Height-adjusted normal reference curves and formulas were created. The mean LV quality in surviving patients who underwent BiVR was better than that in those who underwent SVP. The lowest limits for LV quality in one survivor of BiVR were 39.1% LVEDV, 49.0% LVMM, and 44.9% MAA. During follow up, the LV quality of patients who received BiVR shifted to the normal range. LV quality should be at least greater than 45% of normal values to promise survival in patients with DRVs who are being considered for a BiVR.

Normalized Echocardiographic Values From Guideline-Directed Dedicated Views for Cardiac Dimensions and Left Ventricular Function

BackgroundContinuous technologic development and updated recommendations for image acquisitions creates a need to update the current normal reference ranges for echocardiography. The best method of indexing cardiac volumes is unknown. ObjectivesThe authors used 2- and 3-dimensional echocardiographic data from a large cohort of healthy individuals to provide updated normal reference data for dimensions and volumes of the cardiac chambers as well as central Doppler measurements. MethodsIn the fourth wave of the HUNT (Trøndelag Health) study in Norway 2,462 individuals underwent comprehensive echocardiography. Of these, 1,412 (55.8% women) were classified as normal and formed the basis for updated normal reference ranges. Volumetric measures were indexed to body surface area and height in powers of 1 to 3. ResultsNormal reference data for echocardiographic dimensions, volumes, and Doppler measurements were presented according to sex and age. Left ventricular ejection fraction had lower normal limits of 50.8% for women and 49.6% for men. According to sex-specific age groups, the upper normal limits for left atrial end-systolic volume indexed to body surface area ranged from 44 mL/m2 to 53 mL/m2, and the corresponding upper normal limit for right ventricular basal dimension ranged from 43 mm to 53 mm. Indexing to height raised to the power of 3 accounted for more of the variation between sexes than indexing to body surface area. ConclusionsThe authors present updated normal reference values for a wide range of echocardiographic measures of both left- and right-side ventricular and atrial size and function from a large healthy population with a wide age-span. The higher upper normal limits for left atrial volume and right ventricular dimension highlight the importance of updating reference ranges accordingly following refinement of echocardiographic methods.

Sural nerve conduction: Amplitude and distal latency of sensory nerve action potential

Background: The sensory nerve action potential (SNAP) is an important factor in the electro diagnostic evaluation of a patient with suspected peripheral neuropathy. Sural nerve is the most frequently studied nerve in the electrophysiology. For proper diagnosis sural sensory conduction abnormalities, a reference data are required for each electrophysiology laboratory. Aims and Objectives: The aim of the study was to find out normative reference data of amplitude and distal latency (DL) of sural SNAP for Northern Kerala population. Materials and Methods: The study was designed as cross-sectional and observational study and analysis of values was done using SPSS version 16. A total of 250 healthy subjects of age 15–50 from Northern Kerala participated in the study which included equal number of males and females. Results: Normative reference data for sensory amplitude and DL were derived in the present study. Sensory amplitude was more and DL was found to be less in female population, indicating faster nerve conduction in female. Conclusion: The reference data derived here can be utilized to detect any abnormality sural nerve sensory conduction. The gender effect on sural nerve sensory conduction parameters can be attributed to the height difference, as nerve conduction velocity is inversely proportional to height.

Cortical bone material / compositional properties in growing children and young adults aged 1.5–23 years, as a function of gender, age, metabolic activity, and growth spurt

Bone material / compositional properties are significant determinants of bone quality, thus strength. Raman spectroscopic analysis provides information on the quantity and quality of all three bone tissue components (mineral, organic matrix, and tissue water). The overwhelming majority of the published reports on the subject concern adults. We have previously reported on these properties in growing children and young adults, in the cancellous compartment. The purpose of the present study was to create normative reference data of bone material / compositional properties for children and young adults, in the cortical compartment. We performed Raman (Senterra (Bruker Optik GmbH), 50× objective, with an excitation of 785nm (100mW) and a lateral resolution of ~0.6μm) microspectroscopic analysis of transiliac bone samples from 54 individuals between 1.5 and 23years of age, with no known metabolic bone disease, and which have been previously used to establish histomorphometric, bone mineralization density distribution, and cancellous bone quality reference values. The bone quality indices that were determined were: mineral/matrix ratio (MM) from the integrated areas of the v2PO4 (410-460cm-1) and the amide III (1215-1300cm-1) bands, tissue water in nanopores approximated by the ratio of the integrated spectral area~494-509cm-1 to Amide III band, the glycosaminoglycan (GAG) content (ratio of integrated area 1365-1390cm-1 to the Amide III band, the sulfated proteoglycan (sPG) content as the ratio of the integrated peaks ~1062cm-1 and 1365-1390cm-1, the pyridinoline (Pyd) content estimated from the ratio of the absorbance height at 1660cm-1 / area of the amide I (1620-1700cm-1) band, and the mineral maturity / crystallinity (MMC) estimated from the inverse of the full width at half height of the v1PO4 (930-980cm-1) band. Analyses were performed at the three distinct cortical surfaces (endosteal, osteonal, periosteal) at specific anatomical microlocations, namely the osteoid, and the three precisely known tissue ages based on the presence of fluorescence double labels. Measurements were also taken in interstitial bone, a much older tissue that has undergone extensive secondary mineralization. Overall, significant dependencies of the measured parameters on tissue age were observed, while at any given tissue age, sex and subject age were minimal confounders. The established Raman database in the cortical compartments complements the previously published one in cancellous bone, and provides healthy baseline bone quality indices that may serve as a valuable tool to identify alterations due to pediatric disease.

The Post-Concussion Symptom Scale: Normative Data for Adolescent Student-Athletes Stratified by Gender and Preexisting Conditions

Background: The Post-Concussion Symptom Scale (PCSS) is a self-report questionnaire measuring symptoms that commonly occur after a concussion; however, these symptoms are nonspecific and can be related to co-occurring orthopaedic injuries (eg, cervical strain) or patient characteristics and preexisting conditions, even in the absence of a recent injury. As such, clinicians may have difficulty determining whether symptom elevations are attributable to a recent concussion as opposed to a confounding injury or a preexisting condition, which may be especially difficult when preinjury baseline symptom data are unavailable. Purpose: This study aimed to further validate the 4-factor model of the PCSS (ie, cognitive, sleep-arousal, physical, and affective symptoms) with adolescent student-athletes and provide normative reference data for each factor and the total score, stratified by gender and preexisting health conditions. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Participants were 9358 adolescent student-athletes who completed the PCSS during a preseason baseline evaluation (mean age, 14.9 years; SD, 1.3 years [range, 13-18 years]; 49.3% boys). The 4-factor model of the PCSS was tested for the full sample and separately for boys and girls using confirmatory factor analysis. Symptom severity percentiles were created for the PCSS total score and each factor, stratified by gender and preexisting conditions (ie, attention-deficit/hyperactivity disorder, mental health history, headache/migraine history, learning disability/dyslexia, academic problems, and concussion history). Results: The 4-factor model of the PCSS replicated in the full sample (comparative fit index [CFI] = 0.959) and in both gender groups (boys: CFI = 0.961; girls: CFI = 0.960). The total PCSS score at the 84th percentile varied by preexisting conditions as follows: healthy participants = 8, attention-deficit/hyperactivity disorder = 18, mental health history = 26, headache/migraine history = 18, learning disability = 19, and academic problems = 17. On all PCSS subscales, participants with a mental health history had the highest scores, and high scores were associated with having >1 preexisting condition. Girls had higher scores than boys for each stratification. Conclusion: The 4-factor model of the PCSS replicates for adolescent student-athletes. Gender, number of preexisting conditions, and mental health history are important factors to account for when interpreting PCSS symptom severity. The normative data provided herein could assist clinicians in determining whether an adolescent student-athlete is presenting with persistent postconcussion symptoms or a typical symptom experience based on their gender and personal health history.