Accuracy of sonographic lower segment thickness and prediction of vaginal birth after caesarean in a resourced-limited setting; Prospective study.

OBJECTIVES: To assess the accuracy of ultrasound measurement of the lower uterine segment (LUS) thickness against findings at laparotomy, and to investigate its correlation with the success rate of vaginal birth after one previous caesarean delivery (CD) in a resource-limited setting. DESIGN: Prospective study. SETTING: Obstetrics and Gynaecology department in a tertiary hospital in Ghana. POPULATION: Women with one previous CD undergoing either a trial of labour (TOLAC) or elective CD. METHODS: Myometrial lower uterine segment thickness (mLUS) and full lower uterine segment thickness (fLUS) were measured with transvaginal ultrasound (TVUS). The women were managed according to local protocols with the clinicians blinded to the ultrasound measurements. The LUS was measured intraoperatively for comparison with ultrasound measurements. MAIN OUTCOME MEASURES: Lower uterine segment findings at laparotomy, successful vaginal birth. RESULTS: A total of 311 pregnant women with one previous CD were enrolled; 147 women underwent elective CD and 164 women underwent a TOLAC. Of the women that underwent TOLAC, 96 (58.5%) women had a successful vaginal birth. The mLUS was comparable to the intraoperative measurement in the elective CD group with LUS thickness <5 mm (bias of 0.01, 95% CI -0.10 to 0.12 mm) whereas fLUS overestimated LUS <5 mm (bias of 0.93, 95% CI 0.80-1.06 mm). Successful vaginal birth rate correlated with increasing mLUS values (odds ratio 1.30, 95% CI 1.03-1.64). Twelve cases of uterine defect were recorded. LUS measurement ≤2.0 mm was associated with an increased risk of uterine defects with a sensitivity of 91.7% (95% CI 61.5-99.8%) and specificity of 81.8% (95% CI 75.8-86.8%). CONCLUSION: Accurate TVUS measurement of the LUS is technically feasible in a resource-limited setting. This approach could help in making safer decisions on mode of birth in limited-resource settings.

Comparison of diffusion ranges at different local anesthetic volumes during superior laryngeal nerve block.

OBJECTIVES: Ultrasound-guided superior laryngeal nerve (SLN) block is a practical and painless approach to avoid the hemodynamic stress response during endotracheal intubation and relieve sore throat after laryngeal surgery. The main purpose of this study was to establish an optimal dosage of local anesthetic when performing SLN block to help anesthetists balance analgesia and side effects. METHODS: Twenty fresh larynx specimens were obtained immediately after resection and then injected with 2-, 3-, 4-, or 5- mL of a lidocaine-blue dye mixture at bilateral SLN puncture sites. Superficial areas of deposited blue dye were measured. Dye leakage and surrounding dyed tissue were recorded. Another 40 patients were included in the ultrasound investigation. Distances between the internal branch of the SLN (iSLN) and adjacent structures were calculated. RESULTS: The dye spread area was greater with the administration of larger doses, especially to the visceral space. A 2- or 3-mL injection of local anesthetic was sufficient to infiltrate the SLN gap. A higher incidence of dye leaking out of the thyrohyoid membrane and anterior epiglottis space was observed; furthermore, there was substantially more dyed hyoid/thyroid cartilage with 4 and 5 mL of injected dye mixture than 2 mL. There was no significant difference between the specimen and ultrasound measurements of for length of iSLN-adjacent structures. CONCLUSIONS: In the Chinese population, 2- or 3- mL of local anesthetic is a safe dose during SLN block. A larger volume could overflow from the cavity to cause complications. The thyrohyoid membrane combined with the superior laryngeal artery is a reliable target for positioning the iSLN during ultrasound-guided regional anesthesia.

Posterior Globe Depth for Optic Nerve Sheath Diameter Measurement in Ocular Ultrasound in Healthy Volunteers.

BACKGROUND: Point-of-care ultrasound (POCUS) is a readily available imaging modality in many emergency departments and health care facilities globally. Optic nerve sheath diameter (ONSD) measurement via ocular ultrasound has been shown to accurately predict increased intracranial pressure. Classically, the preferred technique for sonographic measurement of ONSD has specified measurement at an optimal position of 3 mm posterior to the globe. This study aims to validate an alternative approach of depth measurement (between 3 and 8 mm), with the hypothesis that ONSD should not change in size as the distance posterior to the globe increases. METHODS: Healthy volunteers aged > 18 years were studied. A point 3 mm posterior to the optic disc was located. This was repeated at a point 5 mm as well as 8 mm posterior to the globe. RESULTS: We enrolled 10 healthy participants. When evaluating variability in ONSD measurements at each of the three distances, we found that the difference in the measurements at each distance was statistically significant. In investigating pairwise comparisons, there was no difference between 3 and 5 mm, but there were differences in ONSD measurements at 3 and 8 mm, as well as at 5 and 8 mm. CONCLUSION: POCUS is readily available in many emergency departments and health care facilities across the world. The classically preferred technique for sonographic measurement of ONSD has specified measurement at an optimal position of 3 mm posterior to the globe. Our results identified that ONSD can be measured between 3 and 5 mm with no significant changes.

Utilizing Synergism between the Transverse Abdominal and Pelvic Floor Muscles at Different Postures in Nulliparous Women: A Randomized Case-Control Study.

INTRODUCTION: The aim of the study was to determine the effects of the pelvic floor muscle (PFM) training (PFM-T) in combination with transverse abdominal (TRA) muscle activation (cPFM-T) in female urinary incontinence. METHODS: We enrolled nulliparous women in supine (SUG) (n = 22), sitting (SIG) (n = 19), and control (COG) (n = 14) groups. We conducted an 8-week cPFM-T programme. We examined the effect of training on the parameters with the Kruskal-Wallis test, the pairwise comparisons with the Mann-Whitney U test, and the Wilcoxon rank test with the Bonferroni correction. RESULTS: Before training, 15 participants reported occasional urinary leakage. After cPFM-T, 7 participants reported that urinary leakage had disappeared. Maximal isometric contraction of the PFMs until fatigue improved significantly in the SUG (p < 0.001) and SIG (p = 0.015) groups but not significantly in the COG group (p = 0.499). Holding time increased in the SUG (p = 0.972) and the SIG (p = 0.717) groups and decreased in the COG group (p = 0.132). The dynamic endurance of the PFM improved significantly in the SUG group (p < 0.001) but not in the SIG (p = 0.798) and the COG (p = 0.153) groups. The number of maximal fast contractions within 1 min increased in both the SUG (p < 0.001) and SIG (p = 0.813) groups and decreased in the COG group (p = 0.257). Relaxation improved significantly in the SIG group (p = 0.011). TRA mucle thickness increased in both training groups. CONCLUSION: Slow-twitch fibres of the PFM can be trained effectively with PFM-T in both the body positions.

Variations in the Thickness of the Plantar Fascia After Training Based in Training Race. A Pilot Study.

Plantar fascia (PF) is a connective tissue made up of mostly type 1 collagen that is subjected to constant loads. This study evaluated the effect of continuous running on tissue stress in the PF by measuring changes in the thickness of the PF using ultrasound scans. It was a cross-sectional study involving 24 runners from the University of Valencia, recruited as volunteers between December 2018 and February 2019. A variety of data was recorded: (age, body mass index, type of footwear, number of workouts per week, KM run per week, sports injuries in the last year, pre and postrace ultrasound PF measurements). There were significant differences in the 3 postrace measurements of the left foot (<0.001). PF thicknesses were measured before and after running, with a minimal average difference of 0.4 mm in the medial and central fascicles, and 0.3 mm in the lateral fascicle. We observed PF thicknesses above 4mm in asymptomatic patients with no signs of vascularisation, proving that increased PF thickness is not the only criterion for diagnosis of plantar fasciitis.

Household air pollution, ultrasound measurement, fetal biometric parameters and intrauterine growth restriction.

BACKGROUND: Low birthweight, intrauterine growth restriction (IUGR) and perinatal mortality have been associated with air pollution. However, intervention studies that use ultrasound measurements to assess the effects of household air pollution (HAP) on fetal biometric parameters (FBP) are rare. We investigated the effect of a cookstove intervention on FBP and IUGR in a randomized controlled trial (RCT) cohort of HAP-exposed pregnant Nigerian women. METHODS: We recruited 324 women early in the second trimester of pregnancy. Between 16 and 18 weeks, we randomized them to either continue cooking with firewood/kerosene (control group) or receive a CleanCook stove and ethanol fuel (intervention group). We measured fetal biparietal diameter (BPD), head circumference (HC), femur length (FL), abdominal circumference (AC) and ultrasound-estimated fetal weight (U-EFW) in the second and third trimesters. The women were clinically followed up at six regular time points during their pregnancies. Once during the women's second trimester and once during the third, we made 72-h continuous measurements of their personal exposures to particulate matter having aerodynamic diameter < 2.5 µm (PM2.5). We adopted a modified intent-to-treat approach for the analysis. Differences between the intervention and control groups on impact of HAP on fetal growth trajectories were analyzed using mixed effects regression models. RESULTS: There were no significant differences in fetal growth trajectories between the intervention and control groups. CONCLUSIONS: Larger studies in a setting of low ambient air pollution are required to further investigate the effect of transitioning to a cleaner fuel such as ethanol on intrauterine growth. TRIAL REGISTRATION: ClinicalTrials.gov NCT02394574 ; September 2012.

Morphological Characteristics of Passive and Active Structures of the Foot Across Populations With Different Levels of Physical Activity.

BACKGROUND: Imaging diagnosis plays a fundamental role in the evaluation and management of injuries suffered in sports activities. OBJECTIVE: To analyze the differences in the thickness of the Achilles tendon, patellar tendon, plantar fascia, and posterior tibial tendon in the following levels of physical activity: persons who run regularly, persons otherwise physically active, and persons with a sedentary lifestyle. DESIGN: Cross-sectional and observational. PARTICIPANTS: The 91 volunteers recruited from students at the university and the Triathlon Club from December 2016 to June 2019. The data were obtained (age, body mass index, and visual analog scale for quality of life together with the ultrasound measurements). RESULTS: Tendon and ligament thickness was greater in the runners group than in the sedentary and active groups with the exception of the posterior tibial tendon. The thickness of the Achilles tendon was greater in the runners than in the other groups for both limbs (P = .007 and P = .005). This was also the case for the cross-sectional area (P < .01) and the plantar fascia at the heel insertion in both limbs (P = .034 and P = .026) and for patellar tendon thickness for the longitudinal measurement (P < .01). At the transversal level, however, the differences were only significant in the right limb (P = .040). CONCLUSION: The thickness of the Achilles tendon, plantar fascia, and patellar tendon is greater in runners than in persons who are otherwise active or who are sedentary.

Intra-rater reliability of measurement of abdominal perimuscular connective tissue thickness on ultrasound images.

[Purpose] The thickness of the perimuscular connective tissue (PMCT) reflects muscular atrophy and decreased flexibility that may cause low back pain. However, few studies have used ultrasound imaging to measure PMCT thickness. We aimed to examine and confirm the reliability of ultrasound in measuring the thickness of the PMCT of the abdominal wall muscle. [Participants and Methods] The participants were 38 healthy adult males without chronic back pain. The images were acquired in B mode with the participants in the supine position and the PMCT thickness of the abdominal wall muscle was measured on the images. The intraclass correlation coefficient (ICC) was used to confirm reliability. [Results] The ICC for both within-day and between-day PMCT measurements by ultrasound were 0.7-0.9. The 95% confidence interval ranged from 0.5-0.9. The standard error of measurement (SEM) was 0.02-0.1 mm in the abdominal wall muscle and 0.5 mm in the interrecti distance (IRD). The 95% confidence interval (95% CI) of the minimum detectable change (MDC95) was 0.1-0.3 mm in the abdominal wall muscle and 1.3-1.4 mm in the IRD. [Conclusion] We conducted a study to confirm the reliability of ultrasound-based measurement of PMCT thickness of the abdominal wall muscle, and the ICC results established reliability. However, since the values measured were small (0.02-1.4 mm) and there is a limit to visual observation, it was necessary to measure using computer software.

Using Ultrasound Measurement of the Achilles Tendon in Asymptomatic Runners to Assist in Predicting Tendinopathy.

OBJECTIVES: The Achilles tendon is the strongest tendon in the human body, and Achilles tendinopathy is common in athletes due to the stress imparted by repetitive forces. The prevalence of Achilles tendon abnormalities in asymptomatic elite runners is unknown. Since there is a substantial risk of developing symptomatic tendinopathy in those with abnormal tendons, identifying those asymptomatic athletes with abnormal tendons and characterizing baseline characteristics of elite runners using ultrasound (US) are valuable injury prevention tools. METHODS: This study used US to evaluate the Achilles tendons of 27 asymptomatic National Collegiate Athletic Association Division I cross-country athletes and performed correlations between dominant and nondominant side tendon size (cross-sectional area [CSA] and thickness) and athlete characteristics. Tendons were also assessed for signs of abnormalities that were suggestive of Achilles tendinopathy. RESULTS: The prevalence of tendon abnormalities in asymptomatic collegiate runners was 11%. Among the participants included in this study, dominant and nondominant Achilles tendons did not vary significantly in thickness or CSA (P > .05). The CSA was found to correlate with height, weight, sex, body mass index, and miles run per week (P < .05). Thickness was found to correlate best with miles run per week (P < .05). CONCLUSIONS: A US evaluation of the Achilles tendon has potential to identify changes in tendon size in addition to abnormalities consistent with tendinopathy. As more normative values are identified among various populations, tendon size may have prognostic value for collegiate athletes in the evaluation of Achilles tendinopathy.

[Ultrasound measurement of the testis volume of 0－14 years old Chinese boys].

OBJECTIVE: To obtain the normative values of the testis volume of 0－14 years old Chinese boys by ultrasound measurement. METHODS: We collected the testicular ultrasound data on 1607 Chinese boys with normal testes between January 2016 and June 2019. The boys were aged 0－14 years and divided into 14 age groups, with at least 100 cases in each group. We compared the mean, standard deviation and median of the testis volume among different age groups. RESULTS: The testis grew slowly in volume before 8 years old (0.372－0.678 ml), faster after 9 years old (1.040－4.600 ml), (1.040 ± 0.970) ml at 9－10 years, (1.876 ± 1.631) ml at 10－11 years, (2.831 ± 2.155) ml at 11－12 years, (3.640 ± 2.376) ml at 12－13 years, and (4.600 ± 3.559) ml at 13－14 years, larger in the 0－1 than in the 1－2 years group (ï¼»0.403 ± 0.130ï¼½ vs ï¼»0.372 ± 0.110ï¼½ ml, P = 0.04), negatively correlated in age between the two groups. CONCLUSIONS: Ultrasonography is an effective method for the measurement of the testis volume, which can provide the normative values of the testis volume of the 0－14 years old Chinese boys and some evidence for clinical diagnosis and consultation.

The Influence of Air Pressure on the Dynamics of Flexural Ultrasonic Transducers.

The flexural ultrasonic transducer comprises a piezoelectric ceramic disc bonded to a membrane. The vibrations of the piezoelectric ceramic disc induce flexural modes in the membrane, producing ultrasound waves. The transducer is principally utilized for proximity or flow measurement, designed for operation at atmospheric pressure conditions. However, there is rapidly growing industrial demand for the flexural ultrasonic transducer in applications including water metering or in petrochemical plants where the pressure levels of the gas or liquid environment can approach 100 bar. In this study, characterization methods including electrical impedance analysis and pitch-catch ultrasound measurement are employed to demonstrate the dynamic performance of flexural ultrasonic transducers in air at elevated pressures approaching 100 bar. Measurement principles are discussed, in addition to modifications to the transducer design for ensuring resilience at increasing air pressure levels. The results highlight the importance of controlling the parameters of the measurement environment and show that although the conventional design of flexural ultrasonic transducer can exhibit functionality towards 100 bar, its dynamic performance is unsuitable for accurate ultrasound measurement. It is anticipated that this research will initiate new developments in ultrasound measurement systems for fluid environments at elevated pressures.

Examination of the intrarater reliability of ultrasound measurements of the thickness of the lumbar and lateral abdominal muscles in the prone position.

[Purpose] This study aimed to examine the intrarater reliability when measuring the thickness of the lumbar and lateral abdominal muscles using ultrasound with the participants in the prone position. [Participants and Methods] The participants were 10 healthy adult males without chronic low back pain. The muscle thicknesses of the lumbar multifidus, erector spinae, obliquus externus abdominis, obliquus internus abdominis, and transversus abdominal muscles were measured using ultrasound with the participants in the prone position. [Results] The intraclass correlation coefficients of the within-day and between-day intrarater reliability measurements were 31.1-34.1 mm (lumbar multifidus), 32.0-33.5 mm (erector spinae), 7.4-8.0 mm (obliquus externus abdominis), 9.4-10.4 mm (obliquus internus abdominis), and 2.9-3.4 mm (transversus abdominal). The standard error of measurement and 95% confidence interval of minimal detectable change of the within- and between-day measurements were 0.1-1.2 mm and 0.3-3.4 mm, respectively, for each muscle. [Conclusion] The reliability of measuring the lumbar and lateral abdominal muscles in the prone position using ultrasound was confirmed. It was suggested that measurements during muscle activity and extremity movement are possible when participants are in the prone position.

Split-Ring Resonator Sensor Penetration Depth Assessment Using In Vivo Microwave Reflectivity and Ultrasound Measurements for Lower Extremity Trauma Rehabilitation.

In recent research, microwave sensors have been used to follow up the recovery of lower extremity trauma patients. This is done mainly by monitoring the changes of dielectric properties of lower limb tissues such as skin, fat, muscle, and bone. As part of the characterization of the microwave sensor, it is crucial to assess the signal penetration in in vivo tissues. This work presents a new approach for investigating the penetration depth of planar microwave sensors based on the Split-Ring Resonator in the in vivo context of the femoral area. This approach is based on the optimization of a 3D simulation model using the platform of CST Microwave Studio and consisting of a sensor of the considered type and a multilayered material representing the femoral area. The geometry of the layered material is built based on information from ultrasound images and includes mainly the thicknesses of skin, fat, and muscle tissues. The optimization target is the measured S11 parameters at the sensor connector and the fitting parameters are the permittivity of each layer of the material. Four positions in the femoral area (two at distal and two at thigh) in four volunteers are considered for the in vivo study. The penetration depths are finally calculated with the help of the electric field distribution in simulations of the optimized model for each one of the 16 considered positions. The numerical results show that positions at the thigh contribute the highest penetration values of up to 17.5 mm. This finding has a high significance in planning in vitro penetration depth measurements and other tests that are going to be performed in the future.

Ultrasound and histological measurements of dividing membrane thickness in twin gestations.

OBJECTIVE: To determine how prenatal ultrasound measurements of dividing membrane thickness correlate with postnatal histological measurements and chorionicity in twin gestations. METHODS: This was a prospective, longitudinal cohort study of twin gestations. Dividing membrane thickness was measured by transabdominal ultrasound, with the insonation beam both parallel and perpendicular to the membrane, in the second or third trimester, depending on when care was established. Ultrasound examinations were performed every 4 weeks following initial assessment until delivery. Measurements of membrane thickness from the first ultrasound examination were compared with histological measurements after delivery. RESULTS: A total of 45 twin pregnancies (32 dichorionic, 13 monochorionic) were included. Mean gestational age at initial ultrasound examination was 24.1 ± 7.3 weeks. Parallel ultrasound measurements of membrane thickness were 1.6 ± 0.8 mm for monochorionic and 2.5 ± 0.9 mm for dichorionic gestations (P = 0.001). Perpendicular ultrasound measurements were 1.6 ± 0.3 mm for monochorionic and 2.2 ± 0.8 mm for dichorionic gestations (P = 0.009). Inter- and intraobserver reliability of ultrasound measurements were 0.847 and 0.950, respectively. Parallel and perpendicular ultrasound measurements correlated better with each other (R = 0.807, P < 0.001) than with histological measurements of membrane thickness (Rparallel = 0.538, P < 0.001; Rperpendicular = 0.529, P < 0.001). Receiver-operating characteristics curve analyses to predict histological membrane thickness > 50th percentile resulted in an area under the curve (AUC) of 0.828 for parallel (P < 0.001) and 0.874 for perpendicular (P < 0.001) measurements with a cut-off value of 1.9 mm for both approaches. The AUCs for parallel and perpendicular measurements to predict dichorionicity were 0.892 (P < 0.001) and 0.823 (P < 0.001) with cut-off values of 1.9 and 1.8 mm, respectively. CONCLUSION: Prenatal ultrasound measurement of twin dividing membrane thickness is positively correlated with postnatal histological measurement. Dichorionicity can be determined by a magnified dividing membrane thickness ≥ 1.9 mm. Measurements with the ultrasound beam parallel to the dividing membrane may be more accurate than perpendicular measurements. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

A class of joint models for multivariate longitudinal measurements and a binary event.

Predicting binary events such as newborns with large birthweight is important for obstetricians in their attempt to reduce both maternal and fetal morbidity and mortality. Such predictions have been a challenge in obstetric practice, where longitudinal ultrasound measurements taken at multiple gestational times during pregnancy may be useful for predicting various poor pregnancy outcomes. The focus of this article is on developing a flexible class of joint models for the multivariate longitudinal ultrasound measurements that can be used for predicting a binary event at birth. A skewed multivariate random effects model is proposed for the ultrasound measurements, and the skewed generalized t-link is assumed for the link function relating the binary event and the underlying longitudinal processes. We consider a shared random effect to link the two processes together. Markov chain Monte Carlo sampling is used to carry out Bayesian posterior computation. Several variations of the proposed model are considered and compared via the deviance information criterion, the logarithm of pseudomarginal likelihood, and with a training-test set prediction paradigm. The proposed methodology is illustrated with data from the NICHD Successive Small-for-Gestational-Age Births study, a large prospective fetal growth cohort conducted in Norway and Sweden.

Analyzing the impact of phthalate and DINCH exposure on fetal growth in a cohort with repeated urine collection.

BACKGROUND: Most previous studies investigating the associations between prenatal exposure to phthalates and fetal growth relied on measurements of phthalate metabolites at a single time point. They also focused on weight at birth without assessing growth over pregnancy, preventing the identification of potential periods of fetal vulnerability. We examined the associations between pregnancy urinary phthalate metabolites and fetal growth outcomes measured twice during pregnancy and at birth. METHODS: For 484 pregnant women, we assessed 13 phthalate and two 1,2-cyclohexane dicarboxylic acid, diisononyl ester (DINCH) metabolite concentrations from two within-subject weekly pools of up to 21 urine samples (median of 18 and 34 gestational weeks, respectively). Fetal biparietal diameter, femur length, head and abdominal circumferences were measured during two routine pregnancy follow-up ultrasonographies (median 22 and 32 gestational weeks, respectively) and estimated fetal weight (EFW) was calculated. Newborn weight, length, and head circumference were measured at birth. Associations between phthalate/DINCH metabolite and growth parameters were investigated using adjusted linear regression and Bayesian kernel machine regression models. RESULTS: Detection rates were above 99 % for all phthalate/DINCH metabolites. While no association was observed with birth measurements, mono-iso-butyl phthalate (MiBP) and mono-n-butyl phthalate (MnBP) were positively associated with most fetal growth parameters measured at the second trimester. Specifically, MiBP was positively associated with biparietal diameter, head and abdominal circumferences, while MnBP was positively associated with EFW, head and abdominal circumferences, with stronger associations among males. Pregnancy MnBP was positively associated with biparietal diameter and femur length at third trimester. Mixture of phthalate/DINCH metabolites was positively associated with EFW at second trimester. CONCLUSIONS: In this pregnancy cohort using repeated urine samples to assess exposure, MiBP and MnBP were associated with increased fetal growth parameters. Further investigation on the effects of phthalates on child health would be relevant for expanding current knowledge on their long-term effects.

Identifying diversity of patient anatomy through automated image analysis of clinical ultrasounds.

PURPOSE: Central venous catheterization (CVC) carries inherent risks which can be mitigated through the use of appropriate ultrasound-guidance during needle insertion. This study aims to comprehensively understand patient anatomy as it is visualized during CVC by employing a semi-automated image analysis method to track the internal jugular vein and carotid artery throughout recorded ultrasound videos. METHODS: The ultrasound visualization of 50 CVC procedures were recorded at Penn State Health Milton S. Hershey Medical Center. The developed algorithm was used to detect the vessel edges, calculating metrics such as area, position, and eccentricity. RESULTS: Results show typical anatomical variations of the vein and artery, with the artery being more circular and posterior to the vein in most cases. Notably, two cases revealed atypical artery positions, emphasizing the algorithm's precision in detecting anomalies. Additionally, dynamic vessel properties were analyzed, with the vein compressing on average to 13.4% of its original size and the artery expanding by 13.2%. CONCLUSION: This study provides valuable insights which can be used to increase the accuracy of training simulations, thus enhancing medical education and procedural expertise. Furthermore, the novel approach of employing automated data analysis techniques to clinical recordings showcases the potential for continual assessment of patient anatomy, which could be useful in future advancements.

Difference in Buccal Gingival Thickness between the Mandible and Maxilla in the Aesthetic Zone: A Systematic Review and Meta-Analysis.

Background: Fragile gingival tissue is a risk factor for the development of gingival recessions. Despite the fact that gingival recessions are more commonly seen around anterior mandibular teeth, previous research has predominantly concentrated on the gingival dimensions in the anterior maxilla. The objective was to systematically compare buccal gingival thicknesses between the upper and lower jaws in individuals with healthy gingival conditions in the aesthetic zone. Methods: A comprehensive search of three databases was carried out until October 2023. Gingival thickness differences between the maxilla and mandible were evaluated by calculating the mean differences along with the corresponding 95% confidence interval (CI). Subgroup analysis was conducted based on the measurement area, measurement method, and tooth category. Results: A total of seventeen studies were included in this systematic review. Eleven studies were included in the quantitative analysis. Quantitative analysis comparing gingival thickness around 2100 teeth in the anterior mandible to 2056 teeth in the anterior maxilla revealed a statistically significant thinner buccal gingiva in the mandible (mean difference: 0.16 mm; 95% CI [-0.24, -0.07]; p = 0.0003). Conclusions: The present systematic review revealed a more delicate buccal gingiva in the anterior mandible. However, further scientific validation is required due to the considerable heterogeneity in study design and the potential presence of confounding variables.

Novel nomograms for predicting the risk of low distal bone strength: development and validation in a Chinese population-based observational study.

BACKGROUND: This study aims to develop nomogram models based on the speed of sound (SOS) measurements results along with demographic information to predict the risk of low bone strength (LBS) of radius appropriate to the Chinese population of a broad age spectrum. METHODS: A population-based cross-sectional study was conducted in 5 outpatient clinics located in Zhejiang, the southern part of China. A total of 38,699 participants from 2013 to 2017 were included. Baseline measurements included SOS of the distal radius and clinical risk factor evaluation. Logistic regression models were used to evaluate prognosis and identify independent predictive factors, which were then utilized to establish nomograms for predicting the low bone strength of radius. The discrimination and calibration of nomograms were validated using the calibration plots, the decision curve analysis (DCA), and the receiver operating characteristics curve (ROC). RESULTS: A total of 19,845 of the 38,904 participants ranged in age from 10 to 88 years were selected in this process. LBP nomogram model 1 was constructed based on age, weight, height, BMI, and gender. LBP nomogram model 2 was constructed based on age, height, BMI, and gender. The AUCs for model 1 and model 2 were 0.838 (95% CI: 0.832-0.844) and 0.837 (95% CI: 0.831-0.843), respectively. High-quality calibration plots and DCA in nomogram models were noticed, indicated that the constructed nomogram models were clinically useful. CONCLUSIONS: Our study demonstrates that the nomograms established in this study could effectively evaluate the high-risk population groups of distal radius fracture in China.

In Vitro and In Vivo Biological Assays of Dextran Coated Iron Oxide Aqueous Magnetic Fluids.

The iron oxide nanoparticles coated with different surface coatings were studied and characterized by multiple physicochemical and biological methods. The present paper aims at estimating the toxicity in vitro and in vivo of dextran coated iron oxide aqueous magnetic fluids. The in vitro studies were conducted by quantifying the viability of HeLa cells after their incubation with the samples (concentrations of 62.5−125−250−500 µg/mL at different time intervals). The estimation of the toxicity in vivo of administering dextran coated iron oxide aqueous magnetic fluids (DIO-AMF) with hydrodynamic diameter of 25.73 ± 4 nm to Male Brown Norway rats has been made. Different concentrations (62.5−125−250−500 µg/mL) of dextran coated iron oxide aqueous magnetic fluids were administered for 7 consecutive days. Hematology and biochemistry of the Male Brown Norway rats assessment was performed at various time intervals (24−72 h and 21−28 days) after intra-peritoneal injection. The results showed that high concentrations of DIO-AMF (250 and 500 µg/mL) significantly increased white blood cells, red blood cells, hemoglobin and hematocrit compared to the values obtained for the control group (p < 0.05). Moreover, following the administration of DIO-AMF, the levels of alkaline phosphatase and aspartate aminotransferase increased compared to the control group (p < 0.05). After DIO-AMF administration, no significant difference was observed in the levels of alanine aminotransferase, gamma-glutamyl transpeptidase, urea and creatinine compared to the control group (p < 0.05). The results of the present study showed that dextran coated iron oxide aqueous magnetic fluids in concentrations lower than 250 µg/mL are reliable for medical and pharmaceutical applications.