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Purpose: Neutron therapy is a high linear energy transfer modality that is useful for the treatment of radioresistant head and neck (H&N) cancers. It has been limited to 3-dimensioanal conformal-based fast-neutron therapy (3DCNT), but recent technical advances have enabled the clinical implementation of intensity-modulated neutron therapy (IMNT). This study evaluated the comparative dosimetry of IMNT and 3DCNT plans for the treatment of H&N cancers. Materials and Methods: Seven H&N IMNT plans were retrospectively created for patients previously treated with 3DCNT at the University of Washington (Seattle). A custom RayStation model with neutron-specific scattering kernels was used for inverse planning. Organ-at-risk (OAR) objectives from the original 3DCNT plan were initially used and were then systematically reduced to investigate the feasibility of improving a therapeutic ratio, defined as the ratio of the mean tumor to OAR dose. The IMNT and 3DCNT plan quality was evaluated using the therapeutic ratio, isodose contours, and dose volume histograms. Results: When compared with the 3DCNT plans, IMNT reduces the OAR dose for the equivalent tumor coverage. Moreover, IMNT is most advantageous for OARs in close spatial proximity to the target. For the 7 patients with H&N cancers examined, the therapeutic ratio for IMNT increased by an average of 56% when compared with the 3DCNT. The maximum OAR dose was reduced by an average of 20.5% and 20.7% for the spinal cord and temporal lobe, respectively. The mean dose to the larynx decreased by an average of 80%. Conclusion: The IMNT significantly decreases the OAR doses compared with 3DCNT and provides comparable tumor coverage. Improvements in the therapeutic ratio with IMNT are especially significant for dose-limiting OARs near tumor targets. Moreover, IMNT provides superior sparing of healthy tissues and creates significant new opportunities to improve the care of patients with H&N cancers treated with neutron therapy.

Purpose: We conducted a prospective pilot study to evaluate safety and feasibility of TraceIT, a resorbable radiopaque hydrogel, to improve image guidance for bladder cancer radiation therapy (RT). Methods and Materials: Patients with muscle invasive bladder cancer receiving definitive RT were eligible. TraceIT was injected intravesically around the tumor bed during maximal transurethral resection of bladder tumor. The primary endpoint was the difference between radiation treatment planning margin on daily cone beam computed tomography based on alignment to TraceIT versus standard-of-care pelvic bone anatomy. The Van Herk margin formula was used to determine the optimal planning target volume margin. TraceIT visibility, recurrence rates, and survival were estimated by Kaplan-Meier method. Toxicity was measured by Common Terminology Criteria for Adverse Events version 4.03. Results: The trial was fully accrued and 15 patients were analyzed. TraceIT was injected in 4 sites/patient (range, 4-6). Overall, 94% (95% confidence interval [CI], 90%-98%) of injection sites were radiographically visible at RT initiation versus 71% (95% CI, 62%-81%) at RT completion. The median duration of radiographic visibility for injection sites was 106 days (95% CI, 104-113). Most patients were treated with a standard split-course approach with initial pelvic radiation fields, then midcourse repeat transurethral resection of bladder tumor followed by bladder tumor bed boost fields, and 14/15 received concurrent chemotherapy. Alignment to fiducials could allow for reduced planning target volume margins (0.67 vs 1.56 cm) for the initial phase of RT, but not for the boost (1.01 vs 0.96 cm). This allowed for improved target coverage (D95% 80%-83% to 91%-94%) for 2 patients retrospectively planned with both volumetric-modulated arc therapy and 3-dimensional conformal RT. At median follow-up of 22 months, no acute or late complications attributable to TraceIT placement occurred. No patients required salvage cystectomy. Conclusions: TraceIT intravesical fiducial placement is safe and feasible and may facilitate tumor bed delineation and targeting in patients undergoing RT for localized muscle invasive bladder cancer. Improved image guided treatment may facilitate strategies to improve local control and minimize toxicity.

The management of blunt splenic trauma varies between children and adults, with disparate rates of splenectomy and angioembolization. This practice variation can be explained by some of the most recently published guidelines by the American Pediatric Surgical Association (APSA) and the Western Trauma Association (WTA). This narrative review compares these guidelines, and the evidence behind them. A comparison of the guidelines published in 2023 by WTA and APSA was undertaken, supplemented by recommendations in the 2016 WTA & 2015 ATOMAC guidelines. The publications that underpinned the guidelines were also examined. The recommendations from each guideline were summarized and similarities & differences noted, focusing on initial evaluation and resuscitation, the role of imaging, management strategies, hospitalization and follow up. While both guidelines highlight standardized initial resuscitation, subsequent management of both stable and unstable patients is different: guided by CT findings and hemodynamic status in adults and hemodynamic status alone in children. In stable adults, the grade of injury dictates the use of angioembolization, a therapeutic intervention rarely used in children. Differences with regards to ICU admission, follow up investigations and the use of thromoprophylaxis, also underscore the different management strategies in each cohort. It is hoped that this comparison lays the foundation for further exploration of how a unified guideline may be developed, acknowledging the need for nuanced care and resource optimization., Competing Interests: Declaration of competing interest We declare no conflicts of interest., (Copyright © 2024 Asian Surgical Association and Taiwan Society of Coloproctology. Published by Elsevier B.V. All rights reserved.)

Decommissioning consequences of offshore oil and gas infrastructure removal on marine population dynamics, including connectivity, are not well understood. We modelled the connectivity and metapopulation dynamics of three fish and two benthic invertebrate species inhabiting the natural rocky reefs and offshore oil and gas infrastructure located in the Bass Strait, south-east Australia. Using a network approach, we found that platforms are not major sources, destinations, or stepping-stones for most species, yet act as modest sources for connectivity of Corynactis australis (jewel anemone). In contrast, sections of subsea pipelines appear to act as stepping-stones, source and destination habitats of varying strengths for all study species, except for Centrostephanus rodgersii (long-spined sea urchin). Natural reefs were the main stepping-stones, local source, and destination habitats for all study species. These reefs were largely responsible for the overall metapopulation growth of all study species (average of 96 % contribution across all species), with infrastructure acting as a minor contributor (<2 % average contribution). Full or partial decommissioning of platforms should have a very low or negligible impact on the overall metapopulation dynamics of the species explored, except C. australis, while full removal of pipelines could have a low impact on the metapopulation dynamics of benthic invertebrate species and a moderate impact on fish species (up to 34.1 % reduction in the metapopulation growth). We recommend that the decision to remove offshore infrastructure, either in full or in-part, be made on a platform-by-platform basis and consider contributions of pipelines to connectivity and metapopulation dynamics., Competing Interests: Declaration of competing interest Ronen Galaiduk reports financial support was provided by Esso Australia Pty Ltd (EAPL). Dianne McLean reports a relationship with EAPL that includes: funding grants. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Objectives: We sought to (1) identify the countries in the Latin America/Caribbean Group of the United Nations (GRULAC) that have protocols for brain death/death by neurologic criteria (BD/DNC) and (2) review the similarities and differences between these protocols., Materials and Methods: Between January 2018 and April 2019, we obtained and reviewed BD/DNC protocols from countries in GRULAC., Results: We communicated with contacts in 30/33 countries in GRULAC (91 % of countries) and found that 16 (53 % of countries with contacts, 48 % of Latin American/Caribbean countries) had BD/DNC protocols. Of the 13 protocols that provided a definition of death, 10 (77 %) referred to whole brain death. The number of exams/examiners, prerequisites for BD/DNC, and descriptions of the clinical assessment and apnea test were inconsistent among protocols. Although Brazil and Panama required an ancillary test, the indications for ancillary testing, and the types of accepted ancillary tests, varied by country., Conclusion: BD/DNC determination protocols in the countries in GRULAC are inconsistent. Acknowledging the fact that there are diverse cultural, legal and religious perspectives on death, and human and technological resources differ by region, we recommend that attempts be made to harmonize protocols on BD/DNC both regionally and worldwide., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: We recently described TURN (Thrombolysis risk Using mRS and NIHSS), a computationally simple tool for predicting symptomatic intracerebral hemorrhage (sICH) after IV thrombolysis (rt-PA). Our objective was to compare TURN to existing scores for predicting sICH., Methods: Our internal dataset consisted of 210 ischemic stroke patients receiving IV rt-PA from January 2009 until July 2013 at Yale New Haven Hospital. Our external dataset included 303 patients who received IV rt-PA during the NINDS rt-PA trial. Predictive ability and goodness of fit were quantified by odds ratios (OR) and areas under the receiver operating characteristic curve (AUROC), and compared using unequal variance two-sample t-tests., Results: TURN predicted sICH with a higher OR than ASTRAL in the internal dataset (2.72 versus 1.10, P=0.05). We found no other significant differences in OR or AUROC between TURN and other scores in both datasets., Conclusion: Despite its computational simplicity, TURN predicts sICH with accuracy comparable to existing scores., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: We recently developed Thrombolysis risk Using mRS and NIHSS (TURN), a simple score using only prestroke mRS scores and admission NIHSS scores to predict 90-day outcome after IV thrombolysis in ischemic stroke patients. Our purpose was to develop and test a mobile application for utilization of TURN at the bedside., Methods: We developed Risk rtPA, an iOS mobile application based on TURN for prediction of 90-day excellent and severe outcome after IV thrombolysis. Excellent outcome was defined as 90-day mRS≤1. Severe outcome was defined as 90-day mRS≥5. Predictors for excellent and severe outcome were calculated using the inverse logit of -TURN and TURN respectively. We retrospectively validated our mobile application using data from 303 patients who received IV rt-PA during the NINDS rt-PA trial. Sensitivity and specificity analyses were performed using receiver operating characteristic (ROC) curves., Results: Prediction of excellent and severe outcome using Risk rtPA followed an S-shaped curve as expected. We confirmed this finding using data from the NINDS trial. Cutoffs selected after ROC analysis predicted severe outcome with sensitivity of 94.4% and specificity of 52.2%, and excellent outcome with specificity of 83.9% and sensitivity of 61.2%., Conclusion: The Risk rtPA mobile application predicted 90-day excellent and severe outcome in most clinically relevant cases. This mobile application brings the TURN score to the bedside for prediction of 90-day outcome in ischemic stroke patients being evaluated for IV thrombolysis., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Donation after cardiac death (DCD) has proven effective at increasing the availability of organs for transplantation.We performed a retrospective examination of Massachusetts General Hospital (MGH) records of all 201 donors from 1/1/98 to the 11/2008, including 54 DCD, 115 DBD and 32 DCD candidates that did not progress to donation (DCD-dnp). Comparing three time periods, era 1 (01/98-12/02), era 2 (01/03-12/05) and era 3 (01/06-11/08), DCD’s comprised 14.8,48.4% and 60% of donors, respectively (p = 0.002). A significant increase in the incidence of cardiovascular/cerebrovascular as cause of death was evident in era 3 versus eras 1 and 2; 74% versus 57.1% (p<0.001),as was a corresponding decrease in the incidence of traumatic death. Interestingly, we noted an increase in utilization of aggressive neurological management over time, especially in the DCD group.We detected significant changes in the make-up of the donor pool over the past decade. That the changes in diagnosis over time did not differ between DCD and DBD groups suggests this difference is not responsible for the increase in DCD rates. Instead, we suggest that changes in clinical practice, especially in management of patients with severe brain injury may account for the increased proportion of DCD.

An artificial intelligence expert-based system for facilitating the clinical recognition of occupational and environmental factors in lung disease has been developed in a pilot fashion. It utilizes a knowledge representation scheme to capture relevant clinical knowledge into structures about specific objects (jobs, diseases, etc) and pairwise relations between objects. Quantifiers describe both the closeness of association and risk, as well as the degree of belief in the validity of a fact. An independent inference engine utilizes the knowledge, combining likelihoods and uncertainties to achieve estimates of likelihood factors for specific paths from work to illness. The system creates a series of "paths," linking work activities to disease outcomes. One path links a single period of work to a single possible disease outcome. In a preliminary trial, the number of "paths" from job to possible disease averaged 18 per subject in a general population and averaged 25 per subject in an asthmatic population. Artificial intelligence methods hold promise in the future to facilitate diagnosis in pulmonary and occupational medicine.

Active lifestyles may delay the onset of the functional consequences of chronic disease, potentially increasing active life expectancy. We analyzed the Longitudinal Study of Aging (LSOA) to test the hypothesis that elders participation in an active lifestyle prevents loss of function. Focusing on the cohort aged 70-74 who reported being able to carry 25 lb, walk 1/4 mile, climb 10 steps and do heavy housework without help and without difficulty at baseline, decline was defined as no longer being able to perform these tasks independently and without difficulty 2 years later. Using multivariate logistic regression, results reveal that those who did not report regularly exercising or walking a mile were 1.5 times more likely to decline than those who did, controlling for reported medical conditions and demographic factors. Similar findings (with different models) were observed for both men and women. Findings suggest the potential value of programs oriented toward the primary prevention of functional decline.