Predicting fetal weight by three-dimensional limb volume ultrasound (AVol/TVol) and abdominal circumference / 中华医学杂志(英文版)

BACKGROUND@#Fetal weight is an important parameter to ensure maternal and child safety. The purpose of this study was to use three-dimensional (3D) limb volume ultrasound combined with fetal abdominal circumference (AC) measurement to establish a model to predict fetal weight and evaluate its efficiency.@*METHODS@#A total of 211 participants with single pregnancy (28-42 weeks) were selected between September 2017 and December 2018 in the Beijing Obstetrics and Gynecology Hospital of Capital Medical University. The upper arm (AVol)/thigh volume (TVol) of fetuses was measured by the 3D limb volume technique. Fetal AC was measured by two-dimensional ultrasound. Nine cases were excluded due to incomplete information or the interval between examination and delivery >7 days. The enrolled 202 participants were divided into a model group (134 cases, 70%) and a verification group (68 cases, 30%) by mechanical sampling method. The linear relationship between limb volume and fetal weight was evaluated using Pearson Chi-squared test. The prediction model formula was established by multivariate regression with data from the model group. Accuracy of the model formula was evaluated with verification group data and compared with traditional formulas (Hadlock, Lee2009, and INTERGROWTH-21st) by paired t-test and residual analysis. Receiver operating characteristic curves were generated to predict macrosomia.@*RESULTS@#AC, AVol, and TVol were linearly related to fetal weight. Pearson correlation coefficient was 0.866, 0.862, and 0.910, respectively. The prediction model based on AVol/TVol and AC was established as follows: Y = -481.965 + 12.194TVol + 15.358AVol + 67.998AC, R2adj = 0.868. The scatter plot showed that when birth weight fluctuated by 5% (i.e., 95% to 105%), the difference between the predicted fetal weight by the model and the actual weight was small. A paired t-test showed that there was no significant difference between the predicted fetal weight and the actual birth weight (t = -1.015, P = 0.314). Moreover, the residual analysis showed that the model formula's prediction efficiency was better than the traditional formulas with a mean residual of 35,360.170. The combined model of AVol/TVol and AC was superior to the Lee2009 and INTERGROWTH-21st formulas in the diagnosis of macrosomia. Its predictive sensitivity and specificity were 87.5% and 91.7%, respectively.@*CONCLUSION@#Fetal weight prediction model established by semi-automatic 3D limb volume combined with AC is of high accuracy, sensitivity, and specificity. The prediction model formula shows higher predictive efficiency, especially for the diagnosis of macrosomia.@*TRIAL REGISTRATION@#ClinicalTrials.gov, NCT03002246; https://clinicaltrials.gov/ct2/show/NCT03002246?recrs=e&cond=fetal&draw=8&rank=67.

Localization of the nerve entry points of thigh adductor muscles by spiral computed tomography: a novel anatomical guide for chemical neurolysis in treating muscle spasticity / Localización de los puntos de entrada del nervio de los músculos aductores del muslo mediante tomografía computarizada espiral: una nueva guía anatómica para la neurolosis química en el tratamiento de la espasticidad muscular

The nerve entry points (NEPs) cannot yet be accurately localized for the treatment of thigh adductor muscles spasticity in chemical neurolysis. The aim of this study was to identify the location and depth of the NEPs of thigh adductor muscles by spiral computed tomography (CT) and bony landmarks. Forty lower limbs of twenty adult cadavers were dissected in supine position. A curved line on skin surface from the tip of greater trochanter of femur to the center of pubic tubercle was designated as the horizontal reference line (H). Another curved line from the tip of great trochanter to the lateral epicondyle of femur was designated as the longitudinal reference line (L). Following dissection, the NEPs were labeled with barium sulfate, and their body surface projection points (P) were determined by spiral CT. Projection of NEP in the opposite direction was designated as P'. The percentage location of the intersections (PH and PL) of P with the H and L and the percentage depth of NEPs were determined with the Syngo system. The PH for the NEP of pectineus, gracilis, adductor longus, adductor brevis and adductor magnus muscles branch were located at 76.41±0.71 %, 93.85±2.07 %, 92.05±2.15 %, 80.75±1.20 % and 88.08±1.09 % of the H, respectively. The PLwere at 1.64±0.04 %, 29.89±1.90 %, 16.06±1.32 %, 11.66±0.11 % and 22.94±0.90 % of the L, respectively. The depth of NEP from P points were at 17.52±0.52 %, 38.38±2.75 %, 20.88±0.79 %, 20.35±0.82 % and 39.52±0.67 % of PP', respectively. These results help to carry out more precise localization of the NEPs. It should provide a novel anatomical guide for improving the efficacy and efficiency of chemical neurolysis in treating thigh adductor muscle spasticity.

Aún no se pueden localizar con precisión los puntos de entrada del nervio (PEN) para el tratamiento de la espasticidad de los músculos aductores del muslo a través de la neurólisis química. El objetivo de este estudio fue identificar la ubicación y la profundidad de los PEN de los músculos aductores del muslo mediante tomografía computarizada espiral (TC) y puntos de referencia óseos. Se disecaron loa miembros inferiores de 20 cadáveres adultos en posición supina. Se trazó una línea curva en la superficie de la piel desdeel ápice del trocánter mayor del fémur hasta el centro del tubérculo púbico y se designó como línea de referencia horizontal (H). Otra línea curva desde el ápice del trocánter mayor hasta el epicóndilo lateral del fémur se designó como línea de referencia longitudinal (L). Después de la disección, los PEN se marcaron con sulfato de bario y sus puntos de proyección de la superficie del cuerpo (P) se determinaron mediante TC helicoidal. La proyección de PEN en la dirección opuesta se designó como P '. El porcentaje de ubicación de las intersecciones (PH y PL) de P con H y L y la profundidad porcentual de los PEN se determinaron con el sistema Syngo. Los PH para los PEN de los músculos pectineus, gracilis, adductor longus, aductor brevis y rama aductora del músculo aductor magnus se localizaron en 76,41±0,71 %, 93,85±2,07 %, 92,05±2,15 %, 80,75±1,20 % y 88,08±1,09 % de H, respectivamente. Los PL estuvieron en 1,64±0,04 %, 29,89±1,90 %, 16,06±1,32 %, 11,66±0,11 % y 22,94±0,90 % de la L, respectivamente. La profundidad de PEN de P puntos fue de 17,52±0,52 %, 38,38±2,75 %, 20,88±0,79 %, 20,35±0,82 % y 39,52±0,67 % de PP ', respectivamente. Estos resultados ayudan a realizar una localización más precisa de los PEN. Se debe proponer una nueva guía anatómica para mejorar la eficacia y la eficiencia de la neurólisis química en el tratamiento de la espasticidad del músculo aductor del muslo.

Anterior-posterior thigh diameter measured by two-dimensional sonography. Indicator of fetal age at 18 to 28 weeks gestation?

Little published research exists in the area of fetal thigh biometry, specifically in the use of the anterior-posterior fetal thigh diameter [APTD]. A continuing review of existing practices needs to be coupled with evaluation of alternate or additional methodology. This study evaluated the usefulness and direct correlation of a simple, new method of predicting fetal age by measurement of the anterior-posterior thigh diameter [APTD] in a normal 18-to 28 week pregnancies using two-dimensional sonography. This was a quantitative prospective study of 55 patients in the High Level General Hospital, Alberta, Canada. Anterior-posterior thigh diameters [APTD] were sonographically measured and the normal range for each week of pregnancy was determined five times for reliability. Significant correlation was found between [APTD] and fetal age from simple line regression analysis, with >99.9% confidence intervals at each week from 18 to 28 weeks gestation. There was a correlation of 1 mm APTD per 1 week of fetal age. The standard error of estimation was very low at [0.08664] in edition [r>0.9993] and [p < than 0.0001]. The residual scatter plots confirmed the APTD validity. APTD is a reliable and valid method for assessing fetal age in a normal pregnancy and may be particularly useful when other parameters are unable accurately to predict fetal age. An accurate linear measurement of multiple fetal parameters allows a more complete profile of fetal growth and estimated date of delivery [EDD]. APTD may also be useful in identifying fetal growth problems. All of the values of fetal age lie directly on the "best-fit" regression line. Since the coefficient of determination [Rsq] is very high, this model is very effective