Initial Esophageal Anastomosis Diameter Predicts Treatment Outcomes in Esophageal Atresia Patients With a High Risk for Stricture Development

Background and Aims: Children with esophageal atresia (EA) who undergo surgical repair are at risk for anastomotic stricture, which may need multiple dilations or surgical resection if the stricture proves refractory to endoscopic therapy. To date, no studies have assessed the predictive value of anastomotic diameter on long-term treatment outcomes. Our aim was to evaluate the relationship between anastomotic diameter in the early postoperative period and need for frequent dilations and stricture resection within 1 year of surgical repair.Methods: A retrospective chart review was performed of patients who had EA repair or stricture resection (SR). Medical records were reviewed to evaluate the diameter of the anastomosis at the first endoscopy after surgery, number and timing of dilations needed to treat the anastomotic stricture, and need for stricture resection. A generalized estimating equations (GEE) modeling with a logit link and binomial family was done to analyze the relationship between initial endoscopic anastomosis diameter and the outcome of needing a stricture resection. Median regression was implemented to estimate the association between number of dilations needed based on initial diameter.Results: A total of 121 patients (56 females) with a history of EA (64% long-gap EA) were identified who either underwent Foker repair at 46% or stricture resection with end-to-end esophageal anastomosis at 54%. The first endoscopy occurred a median of 22 days after surgery. Among all cases, a narrower anastomoses were more likely to need stricture resection with an OR of 12.9 (95% CI, 3.52, 47; p < 0.001) in patients with an initial diameter of <3 mm. The number of dilations that patients underwent also decreased as anastomotic diameter increased. This observation showed a significant difference when comparing all diameter categories when looking at all surgeries taken as a whole (p < 0.008).Conclusion: Initial anastomotic diameter as assessed via endoscopy performed after high-risk EA repair predicts which patients will require more esophageal dilations as well as the likelihood for stricture resection. This data may serve to stratify patients into different endoscopic treatment plans.

Imaging Predictive Factors of Abdominal Aortic Aneurysm Growth

Background: Variable imaging methods may add important information about abdominal aortic aneurysm (AAA) progression. The aim of this study is to assess available literature data regarding the predictive imaging factors of AAA growth. Methods: This systematic review was conducted using the PRISMA guidelines. A review of the literature was conducted, using PubMed, EMBASE and CENTRAL databases. The quality of the studies was assessed using the Newcastle-Ottawa Scale. Primary outcomes were defined as AAA growth rate and factors associated to sac expansion. Results: The analysis included 23 studies. All patients (2244; mean age; 69.8 years, males; 85%) underwent imaging with different modalities; the initial evaluation was followed by one or more studies to assess aortic expansion. AAA initial diameter was reported in 13 studies (range 19.9–50.9 mm). Mean follow-up was 34.5 months. AAA diameter at the end was ranging between 20.3 and 55 mm. The initial diameter and intraluminal thrombus were characterized as prognostic factors associated to aneurysm expansion. A negative association between atherosclerosis and AAA expansion was documented. Conclusions: Aneurysm diameter is the most studied factor to be associated with expansion and the main indication for intervention. Appropriate diagnostic modalities may account for different anatomical characteristics and identify aneurysms with rapid growth and higher rupture risk. Future perspectives, including computed mathematical models that will assess wall stress and elasticity and further flow characteristics, may offer valuable alternatives in AAA growth prediction.

Sugar Maple, Red Maple, and Yellow Birch Growth and Mortality in Even-Aged Adirondack Northern Hardwoods

Tree diameter growth models for northern hardwoods commonly used large data sets representing a composite of stands with varying management histories, structural characteristics, and age distributions. Yet common predictor variables like diameter can show differences in growth patterns for stands with different age structures and management histories. To address that, we modeled growth and mortality for sugar maple, red maple, and yellow birch in thinned even-aged Adirondack northern hardwoods. Findings indicate that change in diameter depends on initial diameter for sugar maple, with the rate decreasing exponentially from the largest size class to the smallest. Initial diameter did not prove significant with red maple and yellow birch in these thinned stands, perhaps because of the limited sample of trees of small diameter. Stand relative density and time since treatment affected growth for all three species. Those variables also proved significant for predicting mortality of sugar maple. Analyses revealed fewer losses of sugar and red maples among the larger diameter classes, but no relationship with diameter for yellow birch. Plot relative density did not affect mortality with red maple, but time after thinning had a significant effect on survival of all species. Study Implications Crown thinning and other methods that release upper canopy trees within even-aged stands should result in favorable postthinning growth of sugar maple, red maple, and yellow birch. Yet, the small trees of sugar maple will grow slower than larger ones after release by thinning, and small sugar and red maple have greater probability of dying. Residual stand density will temper the growth of all three species and the survival of sugar maple and yellow birch. Findings suggest that management strategies favoring removal of the large-diameter sugar maple trees of upper canopy positions from an even-aged stand (e.g., diameter-limit cutting) will result in lower rates of diameter increment within the residual stand. That should negatively affect stand dynamics and volume production and result in greater mortality among the remaining sugar and red maple. By contrast, crown thinning will enhance residual tree growth and survival, as well as stand development.

Study of the Behaviour of Senegalese Ballast Materials during Compaction with the C-Mould: Case of Bandia Limestone and Diack Basalt

Work presented in this article focuses on the study of the behaviour of materials from Senegalese quarries during compaction. These are Bandia Limestone (Sindia, Thiès Region) and Diack Basalt (Ngoundiane, Thiès Region). The grain size studied is 25/50 mm as for any material studied for use as railway ballast. The Proctor C-Mould for compacting large diameter materials was made for the occasion. With γdmax = 2.142 g/cm3 and WOPM = 5.3%, the compaction results clearly show the poor behaviour of the limestone under the effect of repeated loads and water. It shows a reduction in fine elements of the aggregates of initial diameter 25/50, as well as a significant cohesion under the effect of water with the formation of a muddy paste. The compaction references that characterize Diack Basalt are: γdmax = 2.15 g/cm3 and WOPM = 0.37%. Diack Basalt's compaction behaviour shows good performance. It does not break down into fine particles and the settling observed during compaction is similar to just tightening the grains and then stabilizing the material.

Evaluation of disk halo size after small incision lenticule extraction (SMILE)

Purpose To investigate changes in objective disk halo size produced by a glare source after small incision lenticule extraction (SMILE) for myopia correction. Methods This prospective clinical study included 45 right eyes of 45 patients with a mean age of 25.40 ± 5.06 years and mean spherical equivalent (SE) of − 6.08 ± 1.90 diopters. Disk halo size was measured with a vision monitor before surgery and at postoperative 1 week and 3 months. Other information was collected, including age, SE, lenticule thickness, lenticule diameter, dark pupil, and pupillary response to light parameters (initial diameter; amplitude, latency, duration, and velocity of contraction; latency, duration, and velocity of dilation; and maximum, minimum, and average pupil size). Results Compared to preoperative values, disk halo size increased significantly at postoperative 1 week (P = 0.026) and returned to baseline at postoperative 3 months (P = 0.349). Preoperative disk halo size significantly correlated with SE (r = − 0.346, P = 0.020), minimum pupil size (r = 0.365, P = 0.014), and average pupil size (r = 0.310, P = 0.038). Disk halo size at postoperative 1 week was significantly correlated with age (r = 0.324, P = 0.030) and minimum pupil size (r = 0.297, P = 0.047). Disk halo size at postoperative 3 months was significantly correlated with lenticule diameter (r = − 0.362, P = 0.015), initial diameter (r = 0.311, P = 0.037), maximum pupil size (r = 0.312, P = 0.037), minimum pupil size (r = 0.440, P = 0.002), and average pupil size (r = 0.373, P = 0.012). Conclusions After SMILE, disk halo size demonstrated a temporary increase and then returned to baseline.

DOZ047.15: Esophageal anastomosis diameter at initial endoscopy after surgery predicts treatment outcomes in patients with esophageal atresia or stricture

Background Children with esophageal atresia (EA) are at risk for anastomotic stricture that may ultimately need surgical resection. No studies have examined the relationship between anastomotic diameter at the time of initial postop endoscopy and treatment outcomes. Methods A retrospective chart review was performed of patients with EA who underwent a Foker procedure for repair of long-gap esophageal atresia (LGEA), primary repair of EA, or stricture resection for refractory stricture who were seen between January 2016 and May 2018. A refractory stricture was defined as one requiring ≥5 dilations ≤5 months after surgery. The anastomosis diameter was estimated by the endoscopist. We divided diameter sizes into the following groups: 1–2.9 mm, 3–4.9 mm, 5–6.9 mm, 7–8.9 mm, 9–10.9 mm, and 11–14 mm. The Wilcoxon rank sum test and Fisher's exact test were used. Results Forty-five patients who had a Foker procedure, 37 who had primary repair, and 58 who had stricture resection were identified. The first EGD occurred a median of 22 days (IQR 21–28) after surgery. Among all EA patients with initial diameter of <3 mm, 82% developed refractory stricture and 41% required stricture resection. Of all patients with initial diameter <5 mm, 74% developed refractory stricture and 33% required stricture resection. Of patients who underwent a Foker procedure with initial diameter <3 mm, 56% required stricture resection; of these patients with initial diameter <5 mm, 53% required stricture resection. Among all EA patients, refractory strictures were significantly more likely in patients with smaller initial diameters (P < 0.001), from 18 patients (82%) with stricture 1–2 mm to 0 patients (0%) with stricture 11–14 mm. Patients with smaller anastomoses were more likely to need stricture resection (P = 0.020); 9 patients (41%) with size 1–2 mm underwent stricture resection, while none (0%) with size 11–14 mm needed stricture resection. These differences remained statistically significant for patients who underwent a Foker procedure (P ≤ 0.001 for stricture resection and refractory stricture). Conclusion Endoscopy performed shortly after EA repair or stricture resection can help predict which patients are more likely to develop a refractory stricture or require a stricture resection.

Modelling investigation of water droplet evaporative freezing in artificial snowmaking

In this paper, a modelling investigation of water droplet evaporative freezing was conducted in order to better understand the snowmaking process and hence to optimise the design of the artificial snowmaking device. To this end, mass and heat transfer theoretical models of a single water droplet cooling in an air space were established and implemented in a numerical model developed using the software COMSOL Multiphysics. The effects of the air temperature, relative humidity and velocity and the water droplet initial diameter and temperature on this process were identified and analysed, and their appropriate ranges for the snowmaking were determined.