3D computational fluid dynamic modelling for pulsatile blood wave propagation in the event of car crash

Blunt traumatic aortic rupture (BTAR) is one of the leading causes of rapid fatality in motor vehicle crashes. The mechanism of BTAR, however, is still not clear due to its complicated process. This paper looks the pattern alteration of blood wave propagation of the aorta caused by impact loading to identify the sources of rupture of aorta. In this paper, a three-dimensional computational fluid dynamic (CFD) human aortic model was established. Pulsatile pressure and velocity, representing the cardiac transient pressure and velocity for the healthy adult, were applied at the inlet and outlets of aortic model as the boundary conditions. Blood flow propagation along the ascending aorta to thoracic descending aorta were analysed using ABAQUS CFD. The results indicate that the waves as a result of the impact loading have a significant effect on the patterns of blood wave propagation, which may be considered as one of the sources of rupture of aorta

A comparative study on the diagnostic utility of ultrasonography with conventional radiography and computed tomography scan in detection of zygomatic arch and mandibular fractures

Objectives: The objective of the following study is to evaluate the usefulness of ultrasonography (USG) in comparison with conventional radiography and computed tomography (CT) scan in the diagnosis of zygomatic arch and mandibular fractures. Materials and Methods: A total of 40 patients with suspected fracture of the zygomatic arch and/or mandibular fractures were included in the study. Two groups (one for zygomatic arch fractures and the other for mandibular fractures) of 20 patients each were designed for the study. Ultrasonographic examinations were performed using small linear probe (LA435, Siemens Acuson Antares) with 10 MHz frequency. Data from CT and conventional radiography were compared with that of USG. Results: Sensitivity and specificity of USG in assessing zygomatic arch fractures were 100% and 100%, respectively; and that of mandibular fractures were 94.74% and 100%, respectively. Overall sensitivity, specificity, positive predictive value, and negative predictive value of USG against CT in diagnosing zygomatic arch and mandibular fractures were found out to be 97.4%, 100%, 100%, and 66.7%, respectively. Conclusion: USG is a very reliable tool in detection of fractures involving zygomatic arch and mandible. It can be used for screening of suspected fractures of zygomatic arch and mandible to avoid unnecessary radiation exposure from conventional radiography and CT scans

Giant submandibular sialolith presenting with sialocutaneous and sialo-oral fistula: A case report and review of literature

Sialolithiasis is a common disease of the salivary glands and a major cause of salivary gland dysfunction. It commonly affects middle-aged and has male predominance. Submandibular gland or its duct is most commonly affected. The size of salivary calculi may vary from less than 1 mm to a few cm in the largest diameter. Salivary stones that exceed 15 mm in any dimension are classified as giant. Association of sialocutaneous or Sialo-oral fistula with salivary stones is considered rare. Long-standing stones with chronic inflammatory process may lead to fistula formation

Structural Strength Improvement of 3D Printing Parts from Topology Optimised Design Using Anisotropic Material Modelling

Additive manufacturing (AM) offers diversity, customisability and creativity, making it an important tool to lead Industry 4.0. Reducing the cost of prototyping, bespoke and small-scale production is some of the key advantages of 3D printing. Parts created by topology optimisation and generative design are usually easier to make by AM. Industrial sectors such as automotive, biomedical and manufacturing have begun to see AM as a cost-effective process for complex components. AM is not without its drawbacks, print failures, distortion, rough surfaces and anisotropic properties, and lack of material data is limiting the quality assurance of this technology. It is known that the mechanical properties of the printed parts are sensitive to specific AM process parameters, e.g. the printing direction to the anisotropic property. In this study, the improvement of the prospective mechanical property of a topologically optimised design of a wheel was carried out. As the mechanical load of a wheel is crucial in its application, the prospective mechanical properties of the wheel to be made by AM are investigated by using simulation so that better outcome from AM may be predicted with the customised process planning

Magnetic resonance spectroscopy assessment of brain injury after moderate hypothermia in neonatal encephalopathy: a prospective multi-centre study

Background In neonatal encephalopathy (NE), the clinical manifestations of injury can only be reliably assessed several years after an intervention, complicating early prognostication and rendering trials of promising neuroprotectants slow and expensive. We aimed to determine the accuracy of thalamic proton magnetic resonance spectroscopy (1H MRS) biomarkers as early predictors of the neurodevelopmental abnormalities observed years after NE. Methods We conducted a prospective multi-centre cohort study across eight neonatal intensive care units, recruiting term neonates who received therapeutic hypothermia for NE. We obtained thalamic 1H MRS 4 to 14 days after birth, which were compared to clinical neurodevelopmental tests performed 18 to 24 months later. The primary endpoint was an abnormal outcome, defined as death, or moderate or severe disability. Receiver operating characteristic (ROC) curves were used to examine the strength of the relationship between selected biomarkers and this outcome. Findings We recruited 223 infants who all underwent MR imaging and spectroscopy at a median (IQR) age of 7 (5 to 10) days, with 190 (85%) followed up for neurological examination at a median (IQR) age of 23 (20 to 25) months. Of those followed up, 31 (16%) had moderate or severe disability, including one death. The thalamic concentration of Nacetylasparate, [NAA], had an area under the ROC curve (AUC) of 0·99 (95% CI 0·94 to 1·00, n=82), and lactate/NAA peak area ratio had an AUC of 0·94 (95% CI 0·89 to 0·97, n=160). From conventional MRI, abnormal signal in the posterior limb of the internal capsule (PLIC) gave an AUC of 0·82 (95% CI 0·76 to 0·87, n=190). Thalamic [NAA] was independently associated with neurodevelopmental outcome scores on multivariable analysis, and had higher prognostic accuracy than conventional MR imaging (98% versus 87%; p<0·001). Interpretation Thalamic 1H MRS measures acquired soon after birth in NE accurately predict neurodevelopment two years later. These could be applied to increase the power of neuroprotection trials, while reducing their duration

Whole-Body Hypothermia vs Targeted Normothermia for Neonates with Mild Encephalopathy: A Multicenter Pilot Randomized Clinical Trial

\ua9 2024 American Medical Association. All rights reserved.Importance: Although whole-body hypothermia is widely used after mild neonatal hypoxic-ischemic encephalopathy (HIE), safety and efficacy have not been evaluated in randomized clinical trials (RCTs), to our knowledge. Objective: To examine the effect of 48 and 72 hours of whole-body hypothermia after mild HIE on cerebral magnetic resonance (MR) biomarkers. Design, Setting, and Participants: This open-label, 3-arm RCT was conducted between October 31, 2019, and April 28, 2023, with masked outcome analysis. Participants were neonates at 6 tertiary neonatal intensive care units in the UK and Italy born at or after 36 weeks\u27 gestation with severe birth acidosis, requiring continued resuscitation, or with an Apgar score less than 6 at 10 minutes after birth and with evidence of mild HIE on modified Sarnat staging. Statistical analysis was per intention to treat. Interventions: Random allocation to 1 of 3 groups (1:1:1) based on age: neonates younger than 6 hours were randomized to normothermia or 72-hour hypothermia (33.5 \ub0C), and those 6 hours or older and already receiving whole-body hypothermia were randomized to rewarming after 48 or 72 hours of hypothermia. Main Outcomes and Measures: Thalamic N-acetyl aspartate (NAA) concentration (mmol/kg wet weight), assessed by cerebral MR imaging and thalamic spectroscopy between 4 and 7 days after birth using harmonized sequences. Results: Of 225 eligible neonates, 101 were recruited (54 males [53.5%]); 48 (47.5%) were younger than 6 hours and 53 (52.5%) were 6 hours or older at randomization. Mean (SD) gestational age and birth weight were 39.5 (1.1) weeks and 3378 (380) grams in the normothermia group (n = 34), 38.7 (0.5) weeks and 3017 (338) grams in the 48-hour hypothermia group (n = 31), and 39.0 (1.1) weeks and 3293 (252) grams in the 72-hour hypothermia group (n = 36). More neonates in the 48-hour (14 of 31 [45.2%]) and 72-hour (13 of 36 [36.1%]) groups required intubation at birth than in the normothermic group (3 of 34 [8.8%]). Ninety-nine neonates (98.0%) had MR imaging data and 87 (86.1%), NAA data. Injury scores on conventional MR biomarkers were similar across groups. The mean (SD) NAA level in the normothermia group was 10.98 (0.92) mmol/kg wet weight vs 8.36 (1.23) mmol/kg wet weight (mean difference [MD], -2.62 [95% CI, -3.34 to -1.89] mmol/kg wet weight) in the 48-hour and 9.02 (1.79) mmol/kg wet weight (MD, -1.96 [95% CI, -2.66 to -1.26] mmol/kg wet weight) in the 72-hour hypothermia group. Seizures occurred beyond 6 hours after birth in 4 neonates: 1 (2.9%) in the normothermia group, 1 (3.2%) in the 48-hour hypothermia group, and 2 (5.6%) in the 72-hour hypothermia group. Conclusions and Relevance: In this pilot RCT, whole-body hypothermia did not improve cerebral MR biomarkers after mild HIE, although neonates in the hypothermia groups were sicker at baseline. Safety and efficacy of whole-body hypothermia should be evaluated in RCTs. Trial Registration: ClinicalTrials.gov Identifier: NCT03409770