The effect of shoulder variation on IMRT and SmartArc for Head and Neck Cancer

Purpose: First, to determine an average and maximum displacement of the shoulder relative to isocenter over the course of treatment. Second, to establish the dosimetric effect of shoulder displacements relative to correct isocenter alignment on the dose delivered to the target and the surrounding structures for head and neck cancer patients. Method and Materials: The frequency of shoulder shifts of various magnitudes relative to isocenter was assessed for 4 patients using image registration software. The location of the center of the right and left humeral head relative to isocenter (usually C2) was found daily from CT on rails scans, and was compared to the location of the humeral heads relative to isocenter on the initial simulation CT. Three Baseline head and neck IMRT and SmartArc plans were generated in Pinnacle based on simulation CTs. The CT datasets (external contour and boney structures) were then modified to represent shifts of the shoulder (relative to isocenter) between 3 mm and 15 mm in the SI, AP, and LR directions. The initial plans were recalculated on the image sets with shifted shoulders. Results: On average, shoulder variation was 2-5 mm in each direction, although displacements of over 1 cm in the inferior and posterior directions occurred. Shoulder shifts induced perturbations in the dose distribution, although generally only for large shifts. Most substantially, large, superior shifts resulted in coverage loss by the 95% isodose line for targets in the lower neck. Inferior shifts elevated the dose to the brachial plexus by 0.6-4.1 Gy. SmartArc plans showed similar loss of target coverage as IMRT plans. Conclusions: The position of the shoulder can have an impact on target coverage and critical structure dose. Shoulder position may need to be considered for setup of head and neck patients depending on target location.

Maternal factors, fetal parameters and the risk of shoulder dystocia

Introduction. Shoulder dystocia is a serious complication of vaginal birth, with an incidence ranging from 0.15% to 2.1% of all births. There are approximately 4 million births per year in the United States and shoulder dystocia will be experienced by approximately 20,000 women each year. Although studies have been reported on shoulder dystocia, few studies have addressed both maternal and fetal risk factors. The purpose of this study was to identify maternal and fetal risk factors for shoulder dystocia while proposing factors that could be used to predict impending shoulder dystocia. ^ Material and methods. Articles were reviewed from Medline Pubmed using the search phrase "Risk factors of shoulder dystocia" and Medline Ovid using the search words "Dystocia", "Shoulder" and "Risk factors". Rigorous selection criteria were used to identify articles to be included in the study. Data collected from identified articles were transferred to STATA 10 software for trend analysis of the incidence of shoulder dystocia and the year of publication and a pair wise correlation was also determined between these two variables. ^ Results. Among a total of 343 studies identified, only 20 met our inclusion criteria and were retained for this review. The incidence of shoulder dystocia ranged from 0.07% to 2% and there was no particular trend or correlation between the incidence of shoulder dystocia and year of publication between 1985 and 2007. Pre-gestational and gestational diabetes, postdatism, obesity, birth weight > 4000g and fundal height at last visit > 40cm were identified as major risk factors in our series of studies. ^ Conclusion. Future strategies to predict shoulder dystocia should focus on pre-gestational and gestational diabetes mellitus, postdatism, obesity, birth weight > 4000g and fundal height at last visit > 40cm. ^

Community health workers: The critical link to sustainable, healthy societies in low-resource settings---A model for the Baylor Shoulder to Shoulder Foundation

Community health workers (CHWs) can serve as a bridge between healthcare providers and communities to positively impact social determinants of health and, thus, the overall health of the population. The potential to effect lasting change is particularly significant within resource-poor settings with limited access to formally trained health care providers such as the small, rural village of Santa Ana Intibucá, Honduras and surrounding areas—located on the geographically and politically isolated border of Honduras and El Salvador. The Baylor Shoulder to Shoulder Foundation (BSTS) works in conjunction with Santa Ana's volunteer health committee to bring a health brigade that has provided health care and public health projects to the area at least twice a year since 2001. They have also hired a full-time Honduran physician, a Honduran in-country administrative director, and built a clinic; yet, no community health worker program exists. This CHW program model is the response to a clear need for a CHW program within the area served by BSTS and presents a CHW program model specific to Santa Ana Intibucá and surrounding areas to be implemented by BSTS. Methods used to develop this model include reviewing the literature for recommendations from leading authorities as well as successfully implemented CHW programs in comparable regions. This information was incorporated into existing knowledge and materials currently being used in the area. Using the CHW model proposed here, each brigade, in conjunction with the communities served, can help develop new modules to respond to the specific health priorities of the region at that time, incorporating consistent modes of contact with the local physician and the CHWs to provide refresher courses, training in new topics of interest, and to be reminded of the importance of community health workers' role as the critical link to healthy societies. With cooperation, effort, and support, the brigade can continue to help integrate a sustainable CHW system in which communities may be able to maximize the care they receive while also learning to care for their own health and the future of their communities.^