A novel artificial intelligence model for measuring fetal intracranial markers during the first trimester based on two-dimensional ultrasound image.

OBJECTIVE: To establish reference ranges of fetal intracranial markers during the first trimester and develop the first novel artificial intelligence (AI) model to measure key markers automatically. METHODS: This retrospective study used two-dimensional (2D) ultrasound images from 4233 singleton normal fetuses scanned at 11+0-13+6 weeks of gestation at the Affiliated Suzhou Hospital of Nanjing Medical University from January 2018 to July 2022. We analyzed 10 key markers in three important planes of the fetal head. Based on these, reference ranges of 10 fetal intracranial markers were established and an AI model was developed for automated marker measurement. AI and manual measurements were compared to evaluate differences, correlations, consistency, and time consumption based on mean error, Pearson correlation analysis, intraclass correlation coefficients (ICCs), and average measurement time. RESULTS: The results of AI and manual methods had strong consistency and correlation (all ICC values >0.75, all r values >0.75, and all P values <0.001). The average absolute error of both only ranged from 0.124 to 0.178 mm. AI achieved a 100% detection rate for abnormal cases. Additionally, the average measurement time of AI was only 0.49 s, which was more than 65 times faster than the manual measurement method. CONCLUSION: The present study first established the normal standard reference ranges of fetal intracranial markers based on a large Chinese population data set. Furthermore, the proposed AI model demonstrated its capability to measure multiple fetal intracranial markers automatically, serving as a highly effective tool to streamline sonographer tasks and mitigate manual measurement errors, which can be generalized to first-trimester scanning.

Age-specific normal reference ranges for 99mTc-DTPA glomerular filtration rate to use with two-sample slope-intercept method and Jodal Brochner-Mortensen correction.

Glomerular filtration rate (GFR) varies with age, the calculation method, and the correction factor for slope-intercept overestimation. Hence, any normal reference range accompanying the results should be suitably adapted to the method used. For Nuclear Medicine Departments using a two-sample slope-intercept method, the lack of appropriate age-specific normal reference range has been a hindrance to adopting the recently updated Jodal Brochner-Mortensen (JBM) correction over other older and more widely used methods. A retrospective analysis of the routine GFR calculation and clinical reports generated locally from 2006 to 2020 was carried out. GFR was calculated with 99mTc-DTPA plasma clearance using a two-sample slope-intercept method with JBM correction. Age-specific normal range equations were developed from normal healthy subjects. Published normal reference ranges were modified with appropriate correction reversal and compared with the locally developed reference ranges. Age-specific normal GFR reference ranges for 99mTc-DTPA with slope-intercept method and JBM correction were developed and validated with current literature. Normal reference range (Mean ± 2SD) for Normalised GFR (ml min-1 (1.73m2)-1) within 95% confidence limits suitable for use with JBM correction is 100.6 ± 35.2 for children above 2 years and 102.9 - 0.00629 × (Age)2 ± 19.4 for adults. Availability of age-specific normal GFR reference ranges applicable to the target population and appropriately tailored to the calculation method and correction factor enables Nuclear Medicine Departments to update their calculation methods in line with the current literature and also facilitates accurate reporting and evaluation of the calculated GFR results.

Evaluation of right myocardial performance index of in vitro fertilization fetuses and spontaneous pregnancy fetuses: a cross-sectional study.

BACKGROUND: Whether the in vitro fertilization (IVF) has an effect on the cardiac function of the fetus is very important to evaluate the safety of the technique. The aim of this paper is to establish normal reference range for the fetal right myocardial performance index (RMPI), and compare the reference range between IVF fetuses and spontaneous pregnancy (SP) fetuses by automatic measurement of the RMPI. METHODS: Three hundred seventy-one spontaneous singleton pregnancies (the control group) and 39 singleton pregnancies conceived by IVF (the experimental group) were enrolled into the current study. An automatic measurement system was used to acquire the RMPI. The cardiac function of the two groups was compared by t-test. RESULTS: There was no significant difference in normal reference range of RMPI between IVF fetuses and SP fetuses (RMPI 0.42 ± 0.05 vs 0.43 ± 0.05). No strong correlation was also noted between RMPI with gestational age and heart rate. CONCLUSIONS: Normal reference ranges of RMPI of IVF fetuses and SP fetuses were established, and no significant difference between IVF fetuses and SP fetuses in RMPI was found. Thus, these findings may suggest that IVF has little impact on cardiac function of the fetus.

Establishment of normal reference ranges for total and separate glomerular filtration rates in living kidney donors by Gates' method after renal depth measured using single-photon emission computed tomography/computed tomography.

BACKGROUND: The underestimation of renal depth by Tønnesen formula in Gates' method, which has been confirmed by many scholars, leads to the underestimation of both separate glomerular filtration rate (gSGFR) and total glomerular filtration rate (gTGFR). This study aimed to establish the normal reference ranges of renal depth-calibrated gTGFR and gSGFR in Chinese healthy adults, and to analyze the influencing factors. METHODS: Renal depth was measured by CT scan followed by technetium 99m-diethylene triamine pentaacetic acid (99mTc-DTPA) renal dynamic imaging by single-photon emission computed tomography/computed tomography (SPECT/CT) in 329 living kidney donors. The renal depth-calibrated gTGFR and gSGFR were calculated by Gates' method with renal depth measured by CT instead of being calculated by the Tønnesen formula. A general linear model based on age, gender, body height, body weight, and BMI was used to analyze factors influencing gSGFR (L), gSGFR (R) and gTGFR. RESULTS: The average gSGFR (L), gSGFR (R), and gTGFR for patients aged 23-64 years old were 49.3±10.1, 49.9±10.4, and 99.1±18.7 mL/min/1.73 m2, respectively. The gSGFR (L), gSGFR (R) and gTGFR for patients aged 41-50 years old were 26.9-69.3, 27.7-68.8, and 57.5-135.3 mL/min/1.73 m2, respectively, and those for patients aged 51-60 years old were 31.0-61.5, 29.5-63.3, and 64.6-120.7 mL/min/1.73 m2, respectively. gSGFR (L), gSGFR (R) and gTGFR had statistical significance with body height and age (P<0.05); however, there was no significant difference with gender, body weight, and BMI (P>0.05). For each 1 year increase in age, the gSGFR (L), gSGFR (R), and gTGFR decreased by 0.17, 0.28, and 0.44 mL/min/1.73 m2, respectively, while for every 1 cm increase in body height, the gSGFR (L), gSGFR (R), and gTGFR decreased by 0.37, 0.36, and 0.74 mL/min/1.73 m2, respectively. CONCLUSIONS: Normal reference ranges for renal depth-calibrated gSGFR (L), gSGFR (R), and gTGFR were established in healthy Chinese adults aged 23-64 years, and gSGFR (L), gSGFR (R), and gTGFR decreased with age and body height.

Sonographic measurements of normal C5-C8 nerve roots in children.

INTRODUCTION: The aim of this study was to use ultrasound to measure the cervical nerve roots in normal children to determine normal reference values. METHODS: A total of 441 children of different ages at the Children's Hospital of Chongqing Medical University were examined by ultrasound. The diameter, circumference, and cross-sectional area of the nerve roots were measured. RESULTS: Ultrasonographic measurements were consistent with the ranking C5 < C6 < C7. The C8 nerve root was thicker than C7 in 60% of the participants. The nerve root measurements increased with increasing age, height, weight, and body surface area. DISCUSSION: Normal reference ranges of the cervical nerve roots in children of different ages were established, and can serve as the basis for measurement in future studies.

Establishment of the Normal Reference Range of Thrombelastogram among the Healthy Population and Pregnants in China.

BACKGROUND: We aimed to establish the reference range of thrombelastogram (TEG) for Chinese healthy volunteers and pregnant women and analyze the influence factors. METHODS: Blood samples were collected from healthy volunteers and pregnant women at five tertiary hospitals (the Third Xiangya Hospital of Central South University, the Second Xiangya Hospital of Central South University, Hunan Provincial People's Hospital, Hunan Cancer Hospital and Changsha Central Hospital) in 2016. The effects of age, gender, blood type, and full-term pregnancy on the reference range of normal TEG for healthy volunteers and pregnant women were studied. The specificity of TEG in detecting coagulation disorder. RESULTS: For healthy volunteers, the normal ranges of TEG parameters were as follows: R, 4.3-9.3 min; K, 1.2-3.2 min; α, 50.2-71.2°; MA, 54.1-71.3 mm; LY30: 0%-2.2%; CI, -3.8-2.4. At least one parameter exceeded the normal range specified by the manufacturer in 20.3% of the healthy volunteers; about 7.6% healthy volunteers were diagnosed as coagulation disorder by the above standards; the specificity of detection was 79.7%. There were significant differences in R, K, α, MA and CI between males and females (P<0.01). For pregnant women, the normal ranges of TEG were as follows: R, 3.9-7.5 min; K, 1.0-2.4 min; α, 57.6-74.9°; MA, 55.7-75.7 mm; LY30, 0%-0.56%; CI, -0.97-3.6. Pregnant women having O blood group had a dramatically prolonged R. Full-term pregnancy had no significant impact on TEG results. CONCLUSION: Compared with pregnant women having non-O blood group, those having O blood group had a dramatically prolonged R and showed greater tendency to hemorrhage during and after parturition.

Sex-specific 99th percentiles derived from the AACC Universal Sample Bank for the Roche Gen 5 cTnT assay: Comorbidities and statistical methods influence derivation of reference limits.

OBJECTIVES: Our purpose was to determine a) overall and sex-specific 99th percentile upper reference limits (URL) and b) influences of statistical methods and comorbidities on the URLs. METHODS: Heparin plasma from 838 normal subjects (423 men, 415 women) were obtained from the AACC (Universal Sample Bank). The cobas e602 measured cTnT (Roche Gen 5 assay); limit of detection (LoD), 3ng/L. Hemoglobin A1c (URL 6.5%), NT-proBNP (URL 125ng/L) and eGFR (60mL/min/1.73m2) were measured, along with identification of statin use, to better define normality. 99th percentile URLs were determined by the non-parametric (NP), Harrell-Davis Estimator (HDE) and Robust (R) methods. RESULTS: 355 men and 339 women remained after exclusions. Overall<50% of subjects had measureable concentrations ≥ LoD: 45.6% no exclusion, 43.5% after exclusion; compared to men: 68.1% no exclusion, 65.1% post exclusion; women: 22.7% no exclusion, 20.9% post exclusion. The statistical method used influenced URLs as follows: pre/post exclusion overall, NP 16/16ng/L, HDE 17/17ng/L, R not available; men NP 18/16ng/L, HDE 21/19ng/L, R 16/11ng/L; women NP 13/10ng/L, HDE 14/14ng/L, R not available. CONCLUSIONS: We demonstrated that a) the Gen 5 cTnT assay does not meet the IFCC guideline for high-sensitivity assays, b) surrogate biomarkers significantly lowers the URLs and c) statistical methods used impact URLs. Our data suggest lower sex-specific cTnT 99th percentiles than reported in the FDA approved package insert. We emphasize the importance of detailing the criteria used to include and exclude subjects for defining a healthy population and the statistical method used to calculate 99th percentiles and identify outliers.

Reserch on the Tlyroid Function Reference Range of Different Pregnancy Period of Normal Pregnant Women / 现代检验医学杂志

Objective To establish the reference range of thyroid function from the normal pregnant women in different pregnant period in Hanzhong region.Methods According to the NACB inclusion criteria,collected local resident pregnant women 4 031 cases,from July 2012 to December 2015.With the combination of random sampling,stratified sampling and cluster sampling,thyroid hormone levels were measured by a fully automated chemiluminescence analyzer and its accompanying reagents.All patients were divided into three groups:998 cases in early pregnancy (T1),1 543 cases in mid-pregnancy (T2),1 490 cases in late pregnancy (T3),and 105 cases of non-pregnant women in childbearing age (T0) were selected as control group.Results The levels of thyroid hormones were different among three periods of pregnant women.TSH were 0.25～5.32,0.42～6.26 and 0.61～7.68 mIU/L respectively in the early,middle and late stages.FT3 were 3.54～6.04,3.57～5.94 and 2.93～5.40 pmol/L,respectively.FT4 was 7.11～16.88,6.78～16.94 and 6.03～16.87 pmol/L.Thyroid hormone levels in pregnant women compared with non-pregnant women,there were significant differences (TSH:x2=233.183,P＜0.05,FT4:x2 =388.12,P＜0.05 and FT3:x2 =558.795,P＜0.05).TSH were lower in early pregnant women comparing to non-pregnancy women,and higher in middle-late pregnant women.The change of FT3 and FT4 were consistent,and reduced with the extension of pregnancy comparing to non-pregnancy women.Conclusion The level of thyroid function in pregnant women were different from non-pregnant women.and the normal reference range of local pregnant specific thyroid hormone should be established.

Determination of normal reference ranges for venous blood count among 526 children aging from 1year old to 12 years old in Shanghai / 国际检验医学杂志

Objective To determine normal reference ranges for venous blood count among children aging from 1 year old to 12 years old.Methods These normal reference ranges were defined in a population of 526 healthy children who had no blood system diseases,allergic diseases,respiratory system diseases,urinary system diseases,digestive system disease,rheumatoid disease,thyroid disease,parasitic infections,malignancies and genetic disease,etc.Values of white blood cell count (WBC),red blood cell count (RBC),hemoglobin (Hb)concentration,red blood cell specific volume (Hct),mean corpusular volume(MCV),mean cell hemoglo-bin (MCH),mean corpuscular hemoglobin(MCHC),platelet (PLT),percentage of neutrophil (NE%),percentage of lymphocyte (LY%),percentage of mononuclear cells (MO%),percentage of acidophilic granulocyte (EOS%).Statistical analysis was done on various parameters that we recorded,and then for every parameter,we could get the various reference ranges for different age groups.Results The subjects were divided into 4 groups based on age.Besides the parameters of WBC count and classification of WBC,the rest of parameters were proved to be of no statistical difference between 4 groups..After an integration of the values,we could get the results as follows:RBC(4.02-5.2)×10 1 2/L,HGB 108-144 g/L,Hct 35.2%-40.4%,MCV 74.6-89.9 fL,MCH 20.9-34.7 pg,MCHC 332- 340 g/L,PLT(157 - 409 )× 10 9/L.WBC count did not have statistical difference between the age group 6-<9 and 9-12,but did have between the rest groups.After an integration of the values of WBC count,it could be conclu-ded that WBC count of age group1-<3 was(4.88-13.38)×10 9/L,that of age group 3-<6 was(4.26-1 1.6)×10 9/L and that of age group 6-12 was (4.24-10.24)×10 9/L.WBC classification results were various in different age groups.The values showed as follows:age group 1-<3 NE:29%-32%,LY:58%-61%;age group 3 -<6 NE:43%-46%,LY:43%-46%;age group 6-<9NE:49%-52%,LY:38%-40%;age group 9 to 12NE:5 1% - 58%,LY:33% - 39%.Conclusion WBC classification re-sults and WBC count do have statistical difference in different age groups.Besides the parameters of WBC count and classification of WBC,the rest of parameters are proved to be of no statistically difference in different age groups.The values of WBC count decrea-ses as the age increases.From WBC classification results,the most apparent fact is that the percentage of neutrophil increases as the age increases but the percentage of lymphocyte is just the contrary.As mentioned above,we suggest that we should establish a spe-cific whole blood count normal reference range for each age group during our laboratory testing work.

Spectral effect: each population must have its own normal midnight salivary cortisol reference values determined.

INTRODUCTION: The mesurement of midnight salivary cortisol provides the most sensitive method for screening of Cushing's sendrome. However the clinical significance of spectral error is the requirement for determination of normal reference values in each population for each test, which will be used as the diagnostic method. Salivary cortisol levels may be affected by individual factors such as nutrition, sleep, medication, activity, and gender. Being a non-invasive method, midnight salivary cortisol (MSC) has been used as a valuable indicator of free plasma cortisol. MATERIAL AND METHODS: Midnight salivary cortisol was assessed in randomly selected 100 Turkish patents who underwent to a detailed physical examination. Saliva samples were collected at 00:00 to plastic tubes with the help of plastic pipettes, without brushing their teeth, but after rinsing their mouth. Salivary cortisol was measured with luminescense immunoassay kit. Differences and correlations were analysed. RESULTS: The mean midnight salivary cortisol of the healthy population was 0.21 ±0.03 µg/dl. Body mass index, age, sex, smoking, exercise, educational status alcohol, had no effect on the MSC. CONCLUSIONS: Consequently, normal salivary cortisol reference ranges must be used for different assays and different populations in order to evaluate more accurately pituitary-adrenal axis pathology in clinical practice.

Pulsatile Ocular Blood Flow in Healthy Koreans

PURPOSE: To determine the normal reference range of pulsatile ocular blood flow (POBF) values in healthy Korean subjects and to find out the factors that may affect them. METHODS: A total of 280 eyes of 280 normal subjects were included in this study. Best corrected visual acuity (BCVA), intraocular pressure (IOP), axial length, POBF, systemic blood pressure, and pulse rate were measured. The mean, standard deviation, range, and the 5th and 95th percentiles of POBF were calculated, and the influences of various parameters to POBF were determined by multiple regression analyses. RESULTS: The mean POBF value was 766.0+/-221.6 microliter/min in men and 1021.1+/-249.5 microliter/min in women. The 5th and 95th percentiles for POBF values were 486.0 microliter/min and 1140.0 microliter/min in men and 672.0 microliter/min and 1458.0 microliter/min in women. The POBF values were significantly influenced by gender, mean blood pressure, pulse rate, and axial length. CONCLUSIONS: Even though the POBF values were influenced by gender, BP, and axial length, we could define the normal reference range of POBF in healthy Koreans.

A prospective longitudinal study of normal reference ranges for the length of fetal limb bones by ultrasound examination / 대한산부인과학회지

OBJECTIVE: To establish the reference ranges for the length of fetal limb bones (femur, tibia, fibula, humerus, ulna, radius, foot) at 12 to 38 weeks' gestation. METHODS: The candidates of this prospective longitudinal study were 43 consecutive women with uncomplicated singleton gestations who initially had antenatal care from the first trimester of pregnancy and follow-up regularly. We performed serial measurements of each limb bone and foot bone length by ultrasound examination every 4 weeks until 28 weeks, and then by 2 weeks until 36 weeks, and weekly thereafter. RESULTS: A total of 2,633 and 321 of fetal limb and foot bone lengths were measured. The reference ranges for the length of limb bones and foot length were presented as mean, 95% confidence interval of the means and in percentile. CONCLUSIONS: Our study results are represented as percentile tables for each of the limb bone length. These results can be provided as standardized data of the fetal limb bone length to distinguish from skeletal dysplasia and may well be suggested as the reference guideline for normal fetal limb bone length in Korea.