Resource use differences of two coexisting chironomid species at localized scales.

Competing species may show positive correlations in abundance through time and space if they rely on a shared resource. Such positive correlations might obscure resource partitioning that facilitates competitor coexistence. Here, we examine the potential for resource partitioning between two ecologically similar midge species (Diptera: Chironomidae) in Lake Mývatn, Iceland. Tanytarsus gracilentus and Chironomus islandicus show large, roughly synchronized population fluctuations, implying potential reliance on a shared fluctuating resource and thereby posing the question of how these species coexist at high larval abundances. We first considered spatial partitioning of larvae. Abundances of both species were positively correlated in space; thus, spatial partitioning across different sites in the lake did not appear to be strong. We then inferred differences in dietary resources with stable carbon isotopes. T. gracilentus larvae had significantly higher δ13C values than C. islandicus, suggesting interspecific differences in resource use. Differences in resource selectivity, tube-building behavior, and feeding styles may facilitate resource partitioning between these species. Relative to surface sediments, T. gracilentus had higher δ13C values, suggesting that they selectively graze on 13C-enriched resources such as productive algae from the surface of their tubes. In contrast, C. islandicus had lower δ13C values than surface sediments, suggesting reliance on 13C-depleted resources that may include detrital organic matter and associated microbes that larvae selectively consume from the sediment surface or within their burrow walls. Overall, our study illustrates that coexisting and ecologically similar species may show positive correlations in space and time while using different resources at fine spatial scales.

Low-Cost Alternative for Online Analysis of Volatile Organic Compounds.

The use of online mass spectrometry for detecting volatile organic compounds (VOCs) has proven to be a powerful technique, allowing for real-time analysis of many chemical and biochemical processes. Unfortunately, online mass spectrometry has had limited application due to high instrument costs and limited availability. Here, we detail the design, construction, and performance characteristics of a custom ion-molecule reactor retrofitted to a commonly used single quadrupole mass spectrometer to operate as an online chemical ionization mass spectrometer (CIMS). This low-cost modified CIMS is capable of limits of detection below 10 parts per trillion for select VOCs including dimethyl sulfide, dimethylamine, and trimethylamine.

"This is an illness. No one is supposed to be treated badly": community-based stigma assessments in South Africa to inform tuberculosis stigma intervention design.

Background: Though tuberculosis (TB)-related stigma is a recognized barrier to care, interventions are lacking, and gaps remain in understanding the drivers and experiences of TB-related stigma. We undertook community-based mixed methods stigma assessments to inform stigma intervention design. Methods: We adapted the Stop TB Partnership stigma assessment tool and trained three peer research associates (PRAs; two TB survivors, one community health worker) to conduct surveys with people with TB (PWTB, n = 93) and caregivers of children with TB (n = 24) at peri-urban and rural clinic sites in Khayelitsha, Western Cape, and Hammanskraal, Gauteng Province, South Africa. We descriptively analyzed responses for each stigma experience (anticipated, internal, and enacted), calculated stigma scores, and undertook generalized linear regression analysis. We conducted 25 in-depth interviews with PWTB (n = 21) and caregivers of children with TB (n = 4). Using inductive thematic analysis, we performed open coding to identify emergent themes, and selective coding to identify relevant quotes. Themes were organized using the Constraints, Actions, Risks, and Desires (CARD) framework. Results: Surveys revealed almost all PWTB (89/93, 96%) experienced some form of anticipated, internal, and/or enacted stigma, which affected engagement throughout the care cascade. Participants in the rural setting (compared to peri-urban) reported higher anticipated, internal, and enacted stigma (ß-coefficient 0.72, 0.71, 0.74). Interview participants described how stigma experiences, including HIV intersectional stigma, act individually and together as key constraints to impede care, leading to decisions not to disclose a TB diagnosis, isolation, and exclusion. Stigma resilience arose through the understanding that TB can affect anyone and should not diminish self-worth. Risks of stigma, driven by fears related to disease severity and infectiousness, led to care disengagement and impaired psychological well-being. Participants desired counselling, identifying a specific role for TB survivors as peer counselors, and community education. Conclusions: Stigma is highly prevalent and negatively impacts TB care and the well-being of PWTB, warranting its assessment as a primary outcome rather than an intermediary contributor to poor outcomes. Multi-component, multi-level stigma interventions are needed, including counseling for PWTB and education for health workers and communities. Such interventions must incorporate contextual differences based on gender or setting, and use survivor-guided messaging to foster stigma resilience. Supplementary Information: The online version contains supplementary material available at 10.1186/s44263-024-00070-5.

Early outcomes from the pivotal trial of a four-branch off-the shelf solution to treat complex abdominal and type IV thoracoabdominal aortic aneurysms.

BACKGROUND: This study reports the 30-day outcomes of the primary arm of the GORE EXCLUDER Thoracoabdominal Branch Endoprosthesis (TAMBE) pivotal trial for complex abdominal aortic aneurysm repair. METHODS: This multicenter, nonrandomized, prospective study of the TAMBE device included patients enrolled in the primary study arm of extent IV thoracoabdominal aortic aneurysms and pararenal aneurysms. Technical success and major adverse events were analyzed per the Society for Vascular Surgery guidelines. RESULTS: The 102 patients of the primary arm who underwent endovascular repair using the TAMBE device were a mean age of 73 ± 6.4 years (range, 58-82 years) and 84 (84.2%) were male. The mean body mass index was 28.3 ± 5.0 kg/m2. Fifty-nine patients (57.8%) were treated for extent IV and 43 (42.2%) pararenal aneurysms; the mean maximum diameter of the aneurysms was 59.4 ± 7.8 mm. A prophylactic cerebral spinal fluid drain was used in 10 patients (9.8%). Technical success was achieved in 99% of patients, with the single failure owing to unsuccessful cannulation of the left renal artery. Mean procedure time was 315 ± 103 minutes (range, 163-944 minutes), estimated blood loss was 300 ± 296 mL (range, 10-2000 mL), and contrast administration was 153.6 ± 73.5 mL (range, 16-420 mL). The intensive care unit length of stay was 58.7 ± 52.7 hours (range, 1-288 mL). In 28 patients (27.5%), a total of 32 additional endovascular components were deployed to manage procedural complications including aortic and target vessel dissections and injuries not related to access. Bridging stent grafts were deployed to incorporate 407 target vessels (mean 1.6/per vessel; range, 1-4). Postoperative transfusion was required in 14 patients (13.7%). Major adverse events occurred in seven patients (6.9%) through 30 days. Events included respiratory failure (n = 2), disabling stroke (n = 1), new-onset renal failure requiring dialysis (n = 2), and paraplegia (n = 2). At 30 days, there was one patient with intraoperative rupture; no severe bowel ischemia or lesion-related/all-cause mortality were reported. The Core lab-reported patency was 100% in the aortic component, superior mesenteric artery, and celiac artery, and 95.9% in the left renal and 99.0% in the right renal branch components through 30 days of follow-up. Reinterventions through 30 days were performed in 9 of 96 patients (9.4%) and were all minor. CONCLUSIONS: Early TAMBE device outcomes demonstrate a high technical success rate, no 30-day lesion-related mortality, and a low rate of safety events within 30 days of the index procedure.

Persistent activity of aerobic methane-oxidizing bacteria in anoxic lake waters due to metabolic versatility.

Lacustrine methane emissions are strongly mitigated by aerobic methane-oxidizing bacteria (MOB) that are typically most active at the oxic-anoxic interface. Although oxygen is required by the MOB for the first step of methane oxidation, their occurrence in anoxic lake waters has raised the possibility that they are capable of oxidizing methane further anaerobically. Here, we investigate the activity and growth of MOB in Lake Zug, a permanently stratified freshwater lake. The rates of anaerobic methane oxidation in the anoxic hypolimnion reached up to 0.2 µM d-1. Single-cell nanoSIMS measurements, together with metagenomic and metatranscriptomic analyses, linked the measured rates to MOB of the order Methylococcales. Interestingly, their methane assimilation activity was similar under hypoxic and anoxic conditions. Our data suggest that these MOB use fermentation-based methanotrophy as well as denitrification under anoxic conditions, thus offering an explanation for their widespread presence in anoxic habitats such as stratified water columns. Thus, the methane sink capacity of anoxic basins may have been underestimated by not accounting for the anaerobic MOB activity.

Comparing regularized Kelvinlet functions and the finite element method for registration of medical images to sparse organ data.

Image-guided surgery collocates patient-specific data with the physical environment to facilitate surgical decision making. Unfortunately, these guidance systems commonly become compromised by intraoperative soft-tissue deformations. Nonrigid image-to-physical registration methods have been proposed to compensate for deformations, but clinical utility requires compatibility of these techniques with data sparsity and temporal constraints in the operating room. While finite element models can be effective in sparse data scenarios, computation time remains a limitation to widespread deployment. This paper proposes a registration algorithm that uses regularized Kelvinlets, which are analytical solutions to linear elasticity in an infinite domain, to overcome these barriers. This algorithm is demonstrated and compared to finite element-based registration on two datasets: a phantom liver deformation dataset and an in vivo breast deformation dataset. The regularized Kelvinlets algorithm resulted in a significant reduction in computation time compared to the finite element method. Accuracy as evaluated by target registration error was comparable between methods. Average target registration errors were 4.6 ± 1.0 and 3.2 ± 0.8 mm on the liver dataset and 5.4 ± 1.4 and 6.4 ± 1.5 mm on the breast dataset for the regularized Kelvinlets and finite element method, respectively. Limitations of regularized Kelvinlets include the lack of organ-specific geometry and the assumptions of linear elasticity and infinitesimal strain. Despite limitations, this work demonstrates the generalizability of regularized Kelvinlets registration on two soft-tissue elastic organs. This method may improve and accelerate registration for image-guided surgery, and it shows the potential of using regularized Kelvinlets on medical imaging data.

Risk Factors for Development of Incisional Hernia after Aortic Aneurysm Repair: Secondary Analysis of the OVER Randomized Controlled Trial.

BACKGROUND: Since the risk of mortality from rupture is elevated, elective repair of abdominal aortic aneurysms (AAAs) is often recommended. Currently, over 80% of elective repairs are carried out using an endovascular approach. While open repair has similar late survival and fewer reintervention outcomes when compared to endovascular repair, incisional hernia is a frequent complication with morbidity and cost implications. The Open versus Endovascular Repair (OVER) trial was the largest randomized trial of endovascular versus open repair of AAA in the United States. The purpose of this study was to determine risk factors associated with incisional hernia development following AAA repair via secondary analysis of the OVER data. METHODS: This was a multisite trial conducted within the Veterans Affairs health-care system. Study participants (N = 881) were enrolled from 2002 to 2008 and followed until 2011 with additional administrative data collection until 2016. Eligible patients had AAA for which elective repair was planned and randomized 1:1 to either open or endovascular repair. Incisional hernia was a prespecified end point in the OVER protocol, specifically assessed at each protocol follow-up visit. Technical details were extracted from each operative report, repair case report form(s), and adverse event form(s). Patient demographics, comorbid conditions, reported preoperative activity level, and operative details including initial approach, blood loss, and closure methods were analyzed using Bayesian hierarchical Weibull survival regression modeling. RESULTS: Incisional hernias were recorded among 46 participants (5.2%). The average time to hernia diagnosis was 3.5 years. Of the 437 participants randomized to open treatment, 427 received an open repair including crossovers from endovascular treatment assignment. Transperitoneal repair was performed in 81%, running suture in 96%, and absorbable suture in 71% of cases. Randomization to endovascular repair was associated with reduced risk of hernia (hazard ratio [HR] 0.70, 95% credible interval [CI] 0.49-0.94). Higher activity level was associated with increased hernia risk (HR 1.39, 95% CI 1.06-1.84). Approach, suture closure techniques, body mass index, diabetes, and smoking status were not associated with increased risk of hernia development. CONCLUSIONS: Incisional hernia is a frequent complication associated with open repair of abdominal aortic aneurysm and commonly required reintervention. Endovascular repair was associated with reduced risk of hernia. Patients with increased activity experienced a higher incidence of hernia. However, no other modifiable patient, operative, or technical factors were found to be associated with hernia development.

Effects of state opioid prescribing laws on rates of fatal crashes in the USA.

BACKGROUND: State opioid prescribing cap laws, mandatory prescription drug monitoring programme query or enrolment laws and pill mill laws have been implemented across US states to curb high-risk opioid prescribing. Previous studies have measured the impact of these laws on opioid use and overdose death, but no prior work has measured the impact of these laws on fatal crashes in a multistate analysis. METHODS: To study the association between state opioid prescribing laws and fatal crashes, 13 treatment states that implemented a single law of interest in a 4-year period were identified, together with unique groups of control states for each treatment state. Augmented synthetic control analyses were used to estimate the association between each state law and the overall rate of fatal crashes, and the rate of opioid-involved fatal crashes, per 100 000 licensed drivers in the state. Fatal crash data came from the Fatality Analysis Reporting System. RESULTS: Results of augmented synthetic control analyses showed small-in-magnitude, non-statistically significant changes in all fatal crash outcomes attributable to the 13 state opioid prescribing laws. While non-statistically significant, results attributable to the laws varied in either direction-from an increase of 0.14 (95% CI, -0.32 to 0.60) fatal crashes per 100 000 licensed drivers attributable to Ohio's opioid prescribing cap law, to a decrease of 0.30 (95% CI, -1.17 to 0.57) fatal crashes/100 000 licensed drivers attributable to Mississippi's pill mill law. CONCLUSION: These findings suggest that state-level opioid prescribing laws are insufficient to help address rising rates of fatally injured drivers who test positive for opioids. Other options will be needed to address this continuing injury problem.

Finding Your CAR: The Road Ahead for Engineered T Cells.

Adoptive cellular therapy using chimeric antigen receptors (CARs) has transformed immunotherapy by engineering T cells to target specific antigens on tumor cells. As the field continues to advance, pathology laboratories will play increasingly essential roles in the complicated multi-step process of CAR T-cell therapy. These include detection of targetable tumor antigens by flow cytometry or immunohistochemistry at the time of disease diagnosis and the isolation and infusion of CAR T cells. Additional roles include: i) detecting antigen loss or heterogeneity that renders resistance to CAR T cells as well as identifying alternative targetable antigens on tumor cells, ii) monitoring the phenotype, persistence, and tumor infiltration properties of CAR T cells and the tumor microenvironment for factors that predict CAR T-cell therapy success, and iii) evaluating side effects and biomarkers of CAR T-cell cytotoxicity such as cytokine release syndrome. This review highlights existing technologies that are applicable to monitoring CAR T-cell persistence, target antigen identification, and loss. Also discussed are emerging technologies that address new challenges such as how to put a brake on CAR T cells. Although pathology laboratories have already provided companion diagnostic tests important in immunotherapy (eg, programmed death-ligand 1, microsatellite instability, and human epidermal growth factor receptor 2 testing), we draw attention to the exciting new translational research opportunities in adoptive cellular therapy.

Glucose transporters are key components of the human glucostat.

Mouse models are extensively utilized in metabolic studies. However, inherent differences between the species, notably their blood glucose levels, hampered data translation into clinical settings. In this study, we confirmed GLUT1 to be the predominantly expressed glucose transporter in both adult and fetal human ß cells. In comparison, GLUT2 is detected in a small yet significant subpopulation of adult ß cells and is expressed to a greater extent in fetal ß cells. Notably, GLUT1/2 expression in INS+ cells from human stem cell-derived islet-like clusters (SC-islets) exhibited a closer resemblance to that observed in fetal islets. Transplantation of primary human islets or SC-islets, but not murine islets, lowered murine blood glucose to the human glycemic range, emphasizing the critical role of ß cells in establishing species-specific glycemia. We further demonstrate the functional requirements of GLUT1 and GLUT2 in glucose uptake and insulin secretion through chemically inhibiting GLUT1 in primary islets and SCislets, and genetically disrupting GLUT2 in SC-islets. Finally, we developed a mathematical model to predict changes in glucose uptake and insulin secretion as a function of GLUT1/2 expression. Collectively, our findings illustrate the crucial roles of GLUTs in human ß cells, and identify them as key components in establishing species-specific glycemic setpoints.

Environmental warming increases the importance of high-turnover energy channels in stream food webs.

Warming temperatures are altering communities and trophic networks across Earth's ecosystems. While the overall influence of warming on food webs is often context-dependent, increasing temperatures are predicted to change communities in two fundamental ways: (1) by reducing average body size and (2) by increasing individual metabolic rates. These warming-induced changes have the potential to influence the distribution of food web fluxes, food web stability, and the relative importance of deterministic and stochastic ecological processes shaping community assembly. Here, we quantified patterns and the relative distribution of organic matter fluxes through stream food webs spanning a broad natural temperature gradient (5-27°C). We then related these patterns to species and community trait distributions of mean body size and population biomass turnover (P:B) within and across streams. We predicted that (1) communities in warmer streams would exhibit smaller body size and higher P:B and (2) organic matter fluxes within warmer communities would increasingly skew toward smaller, higher P:B populations. Across the temperature gradient, warmer communities were characterized by smaller body size (~9% per °C) and higher P:B (~7% faster turnover per °C) populations on average. Additionally, organic matter fluxes within warmer streams were increasingly skewed toward higher P:B populations, demonstrating that warming can restructure organic matter fluxes in both an absolute and relative sense. With warming, the relative distribution of organic matter fluxes was decreasingly likely to arise through the random sorting of species, suggesting stronger selection for traits driving high turnover with increasing temperature. Our study suggests that a warming world will favor energy fluxes through "smaller and faster" populations, and that these changes may be more predictable than previously thought.

Diverse Combinatorial Biosynthesis Strategies for C-H Functionalization of Anthracyclinones.

Streptomyces spp. are "nature's antibiotic factories" that produce valuable bioactive metabolites, such as the cytotoxic anthracycline polyketides. While the anthracyclines have hundreds of natural and chemically synthesized analogues, much of the chemical diversity stems from enzymatic modifications to the saccharide chains and, to a lesser extent, from alterations to the core scaffold. Previous work has resulted in the generation of a BioBricks synthetic biology toolbox in Streptomyces coelicolor M1152ΔmatAB that could produce aklavinone, 9-epi-aklavinone, auramycinone, and nogalamycinone. In this work, we extended the platform to generate oxidatively modified analogues via two crucial strategies. (i) We swapped the ketoreductase and first-ring cyclase enzymes for the aromatase cyclase from the mithramycin biosynthetic pathway in our polyketide synthase (PKS) cassettes to generate 2-hydroxylated analogues. (ii) Next, we engineered several multioxygenase cassettes to catalyze 11-hydroxylation, 1-hydroxylation, 10-hydroxylation, 10-decarboxylation, and 4-hydroxyl regioisomerization. We also developed improved plasmid vectors and S. coelicolor M1152ΔmatAB expression hosts to produce anthracyclinones. This work sets the stage for the combinatorial biosynthesis of bespoke anthracyclines using recombinant Streptomyces spp. hosts.

Treating Erythromelalgia with Interosseous Membrane Stimulation: An Autonomic Basis for the Condition and Its Treatment.

Background: Erythromelalgia, which has primary and secondary presentations, causes heat, pain, and redness in the skin. The condition seems to have an autonomic basis, with vasomotor dysfunction causing dilatation of some blood vessels and constriction of others. No consistently effective treatments have been reported. Anticonvulsant, antidepressant, antihistamine, anti-inflammatory, antihypertensive, analgesic, nutritional, and topical approaches have been tried as were lidocaine infusions, nerve blocks, and thoracic and lumbar sympathectomies. Interosseous membrane stimulation appears to affect the local autonomic milieu in the extremity being treated. This approach was used on a patient with erythromelalgia. Case: A 36-year-old woman with erythromelalgia was treated with interosseous membrane stimulation. Eight treatments were given over a 1-year timeframe at 1-3-month intervals. Results: This patient repeatedly experienced much relief from her burning paresthesias, swelling, diaphoresis, and ruddy discoloration of her extremities for 6-8 hours following each treatment. The intensity of her discomfort subsided gradually over time. Conclusions: Interosseous membrane stimulation is a safe, simple, and effective treatment for erythromelalgia, which is notoriously refractory to treatment. This patient's response to treatment might have been a result of localized derangement of her autonomic nervous system. It is possible that manipulation of the autonomic milieu of an extremity is a significant factor in the mechanism of action of interosseous membrane stimulation.

Image-based assessment of aortoiliac aneurysm anatomical characteristics in patients from the global iliac branch study.

OBJECTIVE: Endovascular repair is the preferred treatment for aortoiliac aneurysm, with preservation of at least one internal iliac artery recommended. This study aimed to assess pre-endovascular repair anatomical characteristics of aortoiliac aneurysm in patients from the Global Iliac Branch Study (GIBS, NCT05607277) to enhance selection criteria for iliac branch devices (IBD) and improve long-term outcomes. METHODS: Pre-treatment CT scans of 297 GIBS patients undergoing endovascular aneurysm repair were analyzed. Measurements included total iliac artery length, common iliac artery length, tortuosity index, common iliac artery splay angle, internal iliac artery stenosis, calcification score, and diameters in the device's landing zone. Statistical tests assessed differences in anatomical measurements and IBD-mediated internal iliac artery preservation. RESULTS: Left total iliac artery length was shorter than right (6.7 mm, P = .0019); right common iliac artery less tortuous (P = .0145). Males exhibited greater tortuosity in the left total iliac artery (P = .0475) and larger diameter in left internal iliac artery's landing zone (P = .0453). Preservation was more common on right (158 unilateral, 34 bilateral) than left (105 unilateral, 34 bilateral). There were 192 right-sided and 139 left-sided IBDs, with 318 IBDs in males and 13 in females. CONCLUSION: This study provides comprehensive pre-treatment iliac anatomy analysis in patients undergoing endovascular repair with IBDs, highlighting differences between sides and sexes. These findings could refine patient selection for IBD placement, potentially enhancing outcomes in aortoiliac aneurysm treatment. However, the limited number of females in the study underscores the need for further research to generalize findings across genders.

The prey availability and diet of juvenile Atlantic salmon (Salmo salar L.) in low-productivity rivers in northern Europe.

The availability of resources varies across a species distributional range, and a low-productivity area can make a species more vulnerable. We investigated the invertebrate composition and prey choice of juvenile Atlantic salmon (Salmo salar L.) in low-productivity rivers in northeast Iceland, which is one of the species' most northerly distributions. By sampling benthic and drift invertebrate populations, we found that prey availability was similar within and between rivers. Gut content samples showed that the main prey choice for juvenile S. salar was the Chironomidae. The type of food items consumed varied across different weight groups of S. salar, with smaller juveniles having more diverse diet. S. salar did not have a selection preference for chironomids, which indicates that they were eating the highly available prey in their environment, rather than hunting high biomass items such as terrestrial invertebrates and large Dipterans. Estimates of dietary niche showed that S. salar in these low-productivity rivers relied on consuming what was most readily available, the chironomids, and that they must share resources with other salmonid species. This may be due to the low diversity of freshwater invertebrates (fewer prey options), whereas S. salar in nutrient-rich rivers could rely more on terrestrial invertebrates as an additional subsidy in their diet. In conclusion, with limited prey choices, juvenile S. salar in nutrient-poor rivers, especially in a biogeographically isolated region with low species diversity, may increase in vulnerability and decrease in adaptability to environmental change. Management methods that increase benthic prey abundance and diversity are recommended for conserving the S. salar population in a nutrient-poor river.

Initial Outcomes of the Gore TAG Thoracic Branch Endoprosthesis for Endovascular Repair of Blunt Thoracic Aortic Injury.

BACKGROUND: Endovascular repair of blunt thoracic aortic injury (BTAI) has dramatically reduced the morbidity and mortality of intervention. Injuries requiring zone 2 coverage of the aorta traditionally require left subclavian artery (LSA) sacrifice or open revascularization. Furthermore, these injuries are associated with an increased risk of in-hospital mortality and long-term morbidity. Here we report 1-year outcomes of total endovascular repair of BTAI with the GORE® TAG® Thoracic Branch Endoprosthesis for LSA preservation. METHODS: Across 34 investigative sites, 9 patients with BTAI requiring LSA coverage were enrolled in a nonrandomized, prospective study of a single-branched aortic endograft. The thoracic branch endoprosthesis device allows for graft placement proximal to the LSA and incorporates a single side branch for LSA perfusion. RESULTS: This initial cohort included 8 male and 1 female patient with a median age of 43 (22, 76) and 12 months of follow-up. Five total years of follow-up are planned. All participants had grade 3 BTAI. All procedures took place between 2018 and 2019. The median injury severity score was 2 (0, 66). The median procedure time was 109 min (78, 162). All aortic injuries were repaired under general anesthesia and with heparinization. A spinal drain was used in one patient. Post-deployment balloon angioplasty was conducted in one case at the distal landing zone. There was one asymptomatic LSA branch occlusion 6 months after repair. It was attributed to the purposeful proximal deployment of the branch stent to accommodate an early vertebral takeoff. The occlusion did not require revascularization. There were no strokes, mortalities, or aortic adverse events (migration, endoleak, native aortic expansion, dissection, or thrombosis) through 12 months of follow-up. CONCLUSIONS: Initial cohort outcomes suggest that endovascular repair of zone 2 BTAI is feasible and has favorable outcomes using the thoracic branch device with LSA preservation. Additional cases and longer-term follow-up are required for a definitive assessment of the device's safety and durability in traumatic aortic injuries.

Comparison study of intraoperative surface acquisition methods on registration accuracy for soft-tissue surgical navigation.

Purpose: To study the difference between rigid registration and nonrigid registration using two forms of digitization (contact and noncontact) in human in vivo liver surgery. Approach: A Conoprobe device attachment and sterilization process was developed to enable prospective noncontact intraoperative acquisition of organ surface data in the operating room (OR). The noncontact Conoprobe digitization method was compared against stylus-based acquisition in the context of image-to-physical registration for image-guided surgical navigation. Data from n=10 patients undergoing liver resection were analyzed under an Institutional Review Board-approved study at Memorial Sloan Kettering Cancer Center. Organ surface coverage of each surface acquisition method was compared. Registration accuracies resulting from the acquisition techniques were compared for (1) rigid registration method (RRM), (2) model-based nonrigid registration method (NRM) using surface data only, and (3) NRM with one subsurface feature (vena cava) from tracked intraoperative ultrasound (NRM-VC). Novel vessel centerline and tumor targets were segmented and compared to their registered preoperative counterparts for accuracy validation. Results: Surface data coverage collected by stylus and Conoprobe were 24.6%±6.4% and 19.6%±5.0%, respectively. The average difference between stylus data and Conoprobe data using NRM was -1.05 mm and using NRM-VC was -1.42 mm, indicating the registrations to Conoprobe data performed worse than to stylus data with both NRM approaches. However, using the stylus and Conoprobe acquisition methods led to significant improvement of NRM-VC over RRM by average differences of 4.48 and 3.66 mm, respectively. Conclusion: The first use of a sterile-field amenable Conoprobe surface acquisition strategy in the OR is reported for open liver surgery. Under clinical conditions, the nonrigid registration significantly outperformed standard-of-care rigid registration, and acquisition by contact-based stylus and noncontact-based Conoprobe produced similar registration results. The accuracy benefits of noncontact surface acquisition with a Conoprobe are likely obscured by inferior data coverage and intrinsic noise within acquisition systems.