Evaluating the Effectiveness of Cranial Molding for Treatment of Positional Plagiocephaly Using Finite Element Analysis

Since the advent of recommendations for placing infants in the supine position during sleep to reduce the incidence of sudden infant death syndrome, clinicians have noted an increase in the frequency of cranial asymmetry due to deformation of suture sections of the infants’ skulls as a result of constant concentrated stress in one area at the back of their head. This specific form of cranial deformation is known as positional plagiocephaly and its rate of occurrence has increased from 0.3% in 8.2% within the past 30 years. Current treatments and methodologies for preventing and correcting positional plagiocephaly such as stretching exercises, bedding pillows, and cranial molding are not optimized for effectiveness and comfort. Literature surrounding the implementation of these methodologies or devices often assesses the relative effectiveness of each treatment through statistical means, or studies complications associated with their use. There is a lack of quantified mechanical analysis for determining the effectiveness of each treatment or engineered solutions. In this study, a finite element model was created and validated to study the effect of wearing a cranial helmet, as the most effective non-surgical device for treatment of positional plagiocephaly, on reducing concentrated stress from the back of the baby’s head during sleep. The results from this model were then compared to two other finite element models with a healthy baby sleeping in supine position on a pillow, and a patient diagnosed with a severe case of positional plagiocephaly sleeping on the flat side of his head in supine position. The geometries representing the head of the babies in these models are the refined 3D laser-scanned file of a patient’s head contour at Hanger Clinic as well as the cavity inside the cranial helmet that was used for treatment of the baby. After successfully assigning section and contact properties to different regions of the models, applying proper loading and boundary conditions, and performing mesh convergence studies for each of the three models, the average Von Mises stress values of each of the 13 different suture segments of each model were summarized in tables and evaluated using mathematical and qualitative methods. The stress value data obtained from different suture regions of the model with the cranial helmet resulted in the smallest standard deviation among all three populations which supports that wearing the cranial helmet helps to reduce stress concentrations. Use of the cranial helmet during sleep also showed a significant decrease of the average Von Mises stress within the posterior fontanelle by 90% compared to the healthy baby sleeping in supine position and 73.4% compared to the deformed head sleeping on the flat surface of the head. The major limitations of this study are correlated with the simplifying assumptions and geometries in generating and validating the models. Future studies need to focus on overcoming these limitations and generating more complex models using a similar approach. The methods used in this study and the results obtained from the models can serve as a basis for future development of engineered solutions that are more effective than the existing solutions in the market and reduce the side-effects and complications associated with their use

Tug‐Of‐War on Idealized Midlatitude Cyclones Between Radiative Heating From Low‐Level and High‐Level Clouds

We present baroclinic life-cycle simulations with two versions of the atmosphere model ICON to understand how cloud-radiative heating and cooling affect an idealized midlatitude cyclone. Both versions simulate the same cyclone when run without radiation, but disagree when cloud-radiation-interaction is taken into account. The radiative effects of clouds weaken the cyclone in ICON2.1 but strengthen it in ICON2.6. We attribute the disagreement to low-level clouds, which in ICON2.1 are more abundant and show stronger radiative cooling of the boundary layer. We argue that radiative cooling from low-level cloud tops weakens the cyclone by increasing boundary-layer static stability, and that radiative cooling from high-level cloud tops strengthens the cyclone by decreasing static stability in the upper troposphere and sharpening the tropopause. Our results indicate that clouds and the vertical distribution of their radiative heating and cooling can influence the dynamics of midlatitude cyclones

A comparative study of breast surface reconstruction for aesthetic outcome assessment

Breast cancer is the most prevalent cancer type in women, and while its survival rate is generally high the aesthetic outcome is an increasingly important factor when evaluating different treatment alternatives. 3D scanning and reconstruction techniques offer a flexible tool for building detailed and accurate 3D breast models that can be used both pre-operatively for surgical planning and post-operatively for aesthetic evaluation. This paper aims at comparing the accuracy of low-cost 3D scanning technologies with the significantly more expensive state-of-the-art 3D commercial scanners in the context of breast 3D reconstruction. We present results from 28 synthetic and clinical RGBD sequences, including 12 unique patients and an anthropomorphic phantom demonstrating the applicability of low-cost RGBD sensors to real clinical cases. Body deformation and homogeneous skin texture pose challenges to the studied reconstruction systems. Although these should be addressed appropriately if higher model quality is warranted, we observe that low-cost sensors are able to obtain valuable reconstructions comparable to the state-of-the-art within an error margin of 3 mm.Comment: This paper has been accepted to MICCAI201

Consent and parental responsibility - the past, the present and the future

Introduction: Informed consent is the 'permission or agreement' given by the patient for a proposed action. This paper explores the clinician's role in obtaining informed consent, provides an overview of consent and parental responsibility in the UK, and presents practical adjuncts to aid dental professionals in ascertaining who has parental responsibility to delineate persons capable of providing assent on behalf of an underage patient. / Consent and parental responsibility: While the principles of consent have largely stayed constant with time, subtleties in parental responsibility legislation exist in different regions of the UK. An audit exploring consent and parental responsibility knowledge among clinicians within the orthodontic department at the UCLH Eastman Dental Hospital demonstrated that none of the respondents met the gold standard (100%). The results ranged from 59-89% with a mean score of 74%. The majority of questions answered incorrectly related to knowledge of parental responsibility. / Conclusion: It is the responsibility of clinicians providing any care within the UK to stay up to date with legislation and regulations regarding consent and parental responsibility. Knowledge-based questionnaires can highlight areas of knowledge deficit which can be addressed through continuous professional development. This paper provides a flowchart summarising parental responsibility and a prefilled parental responsibility questionnaire as adjuncts to simplify the process of dental professionals ascertaining parental responsibility

Intra-Operative Assessment of Sentinel Lymph Nodes in Breast Cancer

Lymph node status remains an important prognostic indicator for survival in breast cancer. Sentinel lymph node biopsy has become the standard method of assessment of clinically node negative breast cancers. Economic implications as well as patient related factors have lead to the development a number of intra-operative techniques. Review of the emerging trends in the last 4 years show that although routine histological examination remains the gold standard in most centres intra-operative assessment remains the most favourable, timely and cost-effective option to analyse sentinel nodes. Molecular techniques appear to be far more superior to other histological tests such as Frozen Section or Touch Imprint Cytology. Emerging research suggests that molecular techniques can be used to predict the presence of non sentinel node metastasis