Lung sequestration is a rare congenital anomaly characterized by an abnormal mass of lung tissue. It can occur in two forms, either intralobar, where the mass is embedded within the lung tissue, or extralobar, where it develops outside the lung's boundaries. In both cases, removal of this defect involves a complex minimally invasive procedure during which, in brief, the sequestration is isolated and removed. The surgical removal of the pulmonary sequestration represents a complex challenge for surgeons who have to deal with many critical aspects, such as the heartbeat-induced movement of the lung and, in pediatric cases, very limited operating space. For this reason, it is crucial to create a realistic training program that faithfully reproduces the operating conditions and enables surgeons to become familiar with this procedure. The simulator proposed in this work offers a higher level of anatomical realism than existing systems, including critical details such as the visceral pleura and accurately reproduce spatial relationships between anatomical structures. Moreover, the simulation of cardiac motion adds an element of complexity that simulate the challenges of surgery. The simulator was tested in a realistic operating room setup, validating its practical applicability.
Serial plates are not reasonable in material saving and stress dispersion.To design orthopedic plates ideally and conveniently, this paper proposes a method to optimize plates through editing semantic parameters based on average bone model.Firstly, for the reasonable distribution of serial plates in number and size, an average bone model is created from the existing bones, among which each bone has a contribution to the average model.Secondly, a common orthopedic plate with semantic parameters is constructed on average bone model and it can be conveniently modified.Lastly, optimizing the thickness of the plate through finite element analysis and genetic algorithm to meet the stress condition and use as little material as possible.The simulation results indicate that the method can save material and disperse the stress of the plates so that it can effectively optimize the orthopedic plates.
Abstract Pectus Arcuatum, a rare congenital chest wall deformity, is characterized by the protrusion and early ossification of sternal angle thus configuring as a mixed form of excavatum and carinatum features. Surgical correction of pectus arcuatum always includes one or more horizontal sternal osteotomies, consisting in performing a V-shaped horizontal cutting of the sternum (resection prism) by means of an oscillating power saw. The angle between the saw and the sternal body in the V-shaped cut is determined according to the peculiarity of the specific sternal arch. The choice of the right angle, decided by the surgeon on the basis of her/his experience, is crucial for a successful intervention. The availability of a patient-specific surgical guide conveying the correct cutting angles can considerably improve the chances of success and, at the same time, reduce the intervention time. The present paper aims to propose a new CAD-based approach to design and produce custom-made surgical guides, manufactured by using additive manufacturing techniques, to assist the sternal osteotomy. Starting from CT images, the procedure allows to determine correct resection prism and to shape the surgical guide accordingly taking into account additive manufacturing capabilities. Virtually tested against three case studies the procedure demonstrated its effectiveness. Highlights Patient-specific surgical guide improves the chances of success in sternal osteotomy. A CAD-based approach to design and produce custom-made surgical guides is proposed. The proposed framework entails both a series of automatic and user-guided tasks.
Emerging SARS-COV-2 variants are spurring the development of adapted vaccines as public health authorities plan for the fall vaccination strategy. We aimed to estimate the number of infections and hospitalizations prevented by three potential booster strategies in those ≥18 years of age in the United States: Boosting with Moderna’s licensed first generation monovalent vaccine mRNA-1273 (ancestral strain) starting in September 2022, boosting with Moderna’s candidate bivalent vaccine mRNA-1273.214 (ancestral + BA.1 variant of concern [VOC]) starting in September 2022, or boosting with Moderna’s updated candidate bivalent vaccine mRNA-1273.222 (ancestral + BA.4/5 VOC) starting 2 months later in November 2022 due to longer development timeline.
Methods
An age-stratified, transmission dynamic, Susceptible-Exposed-Infection-Recovered (SEIR) model, adapted from previous literature, was used to estimate the number of infections over time; the model contains compartments defined by both SEIR status and vaccination status. A decision tree was subsequently used to estimate the clinical consequences of those infections. Calibration was performed so the model tracks the actual course of the pandemic up to the present time.
Results
Vaccinating with mRNA-1273(Sept), mRNA-1273.214(Sept), and mRNA-1273.222(Nov) is predicted to reduce infections by 34%, 40%, and 18%, respectively, over a 6-month time horizon (September-February) compared to no booster. Similarly, boosting in September prevents substantially more hospitalizations than starting to boost in November with a more effective vaccine (42%, 48%, and 25% for mRNA-1273, mRNA-1273.214, and mRNA-1273.222, respectively, at 6 months compared to no booster). Sensitivity analyses around transmissibility, vaccine coverage, masking, and waning of natural and vaccine-induced immunity changed the magnitude of cases prevented but boosting with mRNA-1273.214 in September consistently prevented more cases of infection and hospitalization than the other two strategies.
Limitations and Conclusions
With the emergence of new variants, key characteristics of the virus that affect estimates of spread and clinical impact also evolve, making estimation of these parameters difficult, especially in heterogeneous populations. Our analysis demonstrated that vaccinating with the bivalent mRNA-1273.214 booster was more effective over a 6-month period in preventing infections and hospitalizations with a BA.4/5 subvariant than the tailored vaccine, simply because it could be deployed 2 months earlier. We conclude that there is no advantage to delay boosting until a BA.4/5 vaccine is available; earlier boosting with mRNA-1273.214 will prevent the most infections and hospitalizations.
The traditional product form design research usually starts from a single aspect such as aesthetics, ergonomics and Kansei engineering, and lacks the comprehensive consideration of multiple constraints.To solve this problem, a product form optimization design method oriented to aesthetics and ergonomics is proposed.First, based on the theory of computational aesthetics, a quantitative product form aesthetic index system is established.Using the entropy method to achieve the comprehensive evaluation of product form aesthetics.The ergonomic evaluation is carried out by measuring the difference between the standard values and the actual values of the design parameters.Then, taking the aesthetic and ergonomic evaluation as game players, a noncooperative game model is established, and the Nash equilibrium is solved to achieve product form optimization.Finally, We verify by experiments that this method can better realize the multifactor fusion design of the product.
Perineal lipoma is an uncommon congenital benign tumor sometimes associated with genitourinary or anorectal malformations. Accessory scrotum and accessory labioscrotal fold are infrequent features, often concurrent with perineal tumors. We describe a single institution experience with three consecutive cases of perineal lipoma associated with external genital anomalies, and a literature review.
Thyroglossal duct cyst (TDC) is the most common congenital abnormality in the neck in children. The purpose of this study was to perform a comprehensive review of all cases of TDC surgically treated at a single institution and to evaluate the factors that influence the rate of recurrence, and the aesthetic outcome of the surgery on follow up.All cases of TDC surgically treated at the Department of Pediatric Surgery at Meyer Hospital from January 2005 to December 2016 were selected. Charts from 248 patients were reviewed and risk factors for recurrence evaluated. A questionnaire was submitted to the patients' parents to determine if postoperative complications were present and standardized neck pictures were requested, to evaluate the cosmetic result . Microsoft Office Excel 2007 for Windows and Graphpad Prism 6 were used for data management and statistical analysis.Simple cyst excision and post-inflammatory fibrosis (P < 0.05) were assessed as important risk factors for the recurrence of TDC. Recurrence rate on Sistrunk procedure was 5%. Variables such as post-inflammatory fibrosis before surgery (P < 0.001), the positioning of a drain (P < 0.01) and the development of recurrence (P < 0.001), negatively influenced the cosmetic result. No thyroglossal duct cyst carcinoma and no long-term postoperative complications were observed.Recurrence rates were higher in patients who underwent simple cyst excision instead of the Sistrunk procedure, as already reported in literature. Presence of post-inflammatory fibrosis and positioning of the drain at surgery were associated with higher rates of recurrence, as well as worse cosmetic outcome.
Objective: The aim of the study is to evaluate early and long-term results of chest wall primary Ewing’s sarcoma patients treated in the time period February 2000–February 2023 by a multidisciplinary approach. Methods: We retrospectively reviewed the medical records of patients who underwent chest wall resection for a primary tumor. Treatment approach, extent of resection, 30-day mortality, overall survival (OS), local recurrence-free survival (LRFS), and metastasis-free survival (MFS) were analyzed. Results: Overall, n = 15 consecutive patients were treated for chest wall primary Ewing’s sarcoma. A median of n = 3 ribs was resected with a median of n = 2 ribs adjacent to the lesion. Resections were extended to the adjacent structures in n = 5 patients (33.3%). In all cases, we performed a prosthetic reconstruction, associated with muscle flap (n = 10, 66.6%) or with rigid titanium bars and muscle flap (n = 6, 40%). A radical resection was accomplished in n = 13 patients (84.6%). The median surgical time was 310 ± 120 min; median hospitalization was 7.8 ± 1.9 days. Post-operative mortality was zero. We recorded n = 4 (30.7%) post-operative complication. The median follow-up (FU) was 26 months. Moreover, 5-year overall and event-free survival were 52% and 48%, respectively. Conclusions: This case series confirms the benefit of the multidisciplinary approach for Ewing sarcomas in early and long-term results.
