Validity of leg length measurement in the supine and standing position compared with pelvic survey X-ray after total hip arthroplasty.

INTRODUCTION: The correct adjustment of leg length is a major goal in the implantation of total hip replacements (THRs). Differences in leg length can lead to functional impairment and patient dissatisfaction. By determining leg length at an early stage, before the patient is discharged from hospital, compensatory measures such as the production of special insoles or orthopaedic footwear can be initiated promptly if there is a difference in leg length. Due to shortening of the period of time spent in hospital, the traditional measurement of leg length in a standing position may be increasingly subject to error. A protective posture immediately after surgery or the presence of a twisted pelvis, for example, due to scoliotic spinal misalignments, falsifies the measurement result in the standing position. Here, the measurement of leg length in the supine position may prove to be accurate immediately postoperatively, regardless of potential sources of error, and is to be compared with measurement in the standing position versus radiological measurement on the AP pelvic survey. MATERIAL AND METHODS: The present retrospective study included 190 patients who had undergone primary total hip arthroplasty. The leg length difference (LLD) of the patients was determined pre- and postoperatively both in the supine and standing position and compared with the postoperative radiological pelvic survey image. RESULTS: Postoperatively, it was shown that the mean length measured was 0.35 mm too long in the supine position and 0.68 mm too short in the standing position (p value < 0.001). Determination of the average absolute measurement error produces a deviation of 4.06 mm in the standing and 4.51 mm in the supine position (p value 0.126). CONCLUSIONS: It is shown that the postoperative measurement of LLD in the supine and standing position is equally valid and sufficiently accurate, compared with the gold standard of measurement on a radiograph.

Less soft tissue release in total knee arthroplasty for anteromedial compared to posteromedial knee osteoarthritis.

In total knee arthroplasty (TKA), the aim of achieving a mechanically straight leg axis as well as symmetrical and equally wide gaps has become established as the gold standard in terms of surgical technique. In contrast to TKA unicompartmental knee arthroplasty (UKA) is performed in anteromedial osteoarthritis (AMOA) and does not normally require releases. This raises the hypothesis whether the type of osteoarthritis (AMOA vs. posteromedial osteoarthritis (PMOA)) determines the requirement for soft tissue releases in TKA.In this retrospective study, 114 patients with medial osteoarthritis of the knee who had been treated with a navigated total knee replacement were consecutively included. On the basis of the preoperative lateral radiographs, the patients were divided into two groups: AMOA and PMOA. The incidence and the extent of releases performed were recorded using the navigation records.Patient-specific data (gender, age) did not differ between the groups (NS). Knees with AMOA presented an overall varus alignment of 5.3 ± 3.5°, knees with PMOA 8.0 ± 4.0° (p < 0.001). 30 cases (44%) had to be released in the AMOA group, compared with 33 cases (72%) in the PMOA group (p = 0.004). In the case of medial release, the extension gap increased 3.3 ± 2.4 mm in the AMOA compared to 5.3 ± 3.7 mm in the PMOA group (p = 0.006). The medial flexion gap was released 2.2 ± 2.6 mm in the AMOA and 2.9 ± 3.0 mm in the PMOA group (p = 0.008).To achieve a neutral mechanical alignment, a release has to be performed due to asymmetry of the extension gap more often if PMOA is present than in AMOA. Surgeons should be prepared to perform more frequent and extensive medial releases in PMOA. Higher constrained implants should be available in case of unintended over release in PMOA.

Topical vancomycin powder does not affect patella cartilage degeneration in primary total knee arthroplasty and conversion rate for secondary patella resurfacing.

INTRODUCTION: Vancomycin powder (VP) is an antibiotic first introduced in pediatric spinal surgery to prevent surgical site infections (SSI). Recently its topical application was expanded to total hip and knee arthroplasty (THA, TKA) and anterior cruciate ligament reconstruction (ACLR). Toxicity to cartilage is the subject of current research. The aim of this study was to prove the hypothesis that topical application of VP in TKA does not result in a degeneration of patella cartilage. We propagate that the conversion rate for secondary patella resurfacing is not influenced by its use. MATERIALS AND METHODS: Between 2014 and 2021, 4292 joints were included in this monocentric retrospective cohort study. All patients underwent TKA without primary patella resurfacing. After a change of the procedure in the hospital, one group (VPG) was administered VP intraoperatively. The other group (nVPG) received no VP during surgery (nVPG). The remaining perioperative procedure was constant over the investigation period. Conversion rates for secondary patella resurfacing for both groups were determined without making distinctions in the indication. A second cohort was composed of patients presenting for follow-up examination 12 months after TKA and included 210 joints. Retrospective radiographic evaluations were performed preoperatively, before discharge and at follow-up examination. Patella axial radiographs were analyzed for patella tracking (lateral patellar tilt, patellar displacement) and patella degeneration (Sperner classification, patellofemoral joint space). RESULTS: There was no significant difference in the conversion rate for secondary patella resurfacing (4.24% VPG, 4.97% nVPG). Patella tracking and patella degeneration did not differ significantly between both groups. CONCLUSIONS: The topical application of VP does not influence the conversion rate for secondary patella resurfacing. Moreover, it does not result in a degeneration of patella cartilage in TK. LEVEL OF EVIDENCE: Retrospective case series, Level III.

C-reactive protein during the first 6 postoperative days after total hip arthroplasty cannot predict early periprosthetic infection.

INTRODUCTION: Periprosthetic joint infection (PJI) after total hip arthroplasty (THA) remains a serious complication in orthopaedic surgery. C-reactive protein (CRP) is widely used as a marker to screen for inflammatory complications. The early postoperative course is well known, but knowledge about the predictive value of CRP in the first 6 postoperative days for detecting an acute postoperative PJI is lacking. METHODS: We retrospectively analyzed the inpatient course of CRP of all primary THA and THA with acute PJI within 28 days in our hospital from 2013 to 2021. A receiver-operating curve (ROC) analysis was performed and the best CRP threshold for detecting an acute PJI based on Youden's-index was calculated and an area-under-the curve (AUC) analysis of the threshold was performed. RESULTS: 33 of 7042 patients included had an acute PJI within 28 days. Patients with acute PJI were older, had a higher BMI and longer operation time and suffered more often from diabetes mellitus. A preoperatively elevated CRP was a risk factor for PJI. CRP was significantly higher in the PJI group on postoperative days 3 and 5. Threshold values were calculated to be 152 mg/l on day 3 and 73 mg/l on day 5. However, these values had a low sensitivity (75%, 76%) and specificity (67%, 61%). CONCLUSION: Especially considering the decreasing length of stay after THA, the question of the usefulness of regular inpatient CRP checks arises. AUC analysis of the ROC showed a poor diagnostic accuracy in almost all cases. Only the dynamic analysis of the maximum CRP value to the lowest CRP value with a decrease of 102.7 mg/l showed a fair accuracy. This calls into question the clinical relevance of CRP in the first postoperative week for detection of acute postoperative PJI.

An exploratory analysis of patient factors influencing acceptance of extended criteria liver grafts.

INTRODUCTION AND OBJECTIVES: There is a shortage of ideal donor organs with consequential increasing waitlist times, drop-off, and mortality. Teams have thus extended the donor criteria. Little is known about patients' actual choices and what factors may influence their decisions regarding different extended criteria liver grafts. PATIENTS AND METHODS: The documented acceptance or refusal of seven extended criteria liver graft types of patients consented for transplant in a single institution over a 2-year period was reviewed. Patient factors including sex, age, indication, aetiology, and model for end-stage liver disease (MELD) score were analysed using logistic regression. RESULTS: Most patients were willing to accept most graft types. MELD score did not impact the acceptance or refusal of any graft type. Older patients and those with hepatocellular carcinoma (HCC) or ascites had significantly higher rates of acceptance. Hepatitis B or C disease aetiology was predictive of willingness to accept a similarly infected graft, respectively. HCC was predictive of acceptance of grafts from donors with a cancer history. CONCLUSIONS: In general, patients embrace the available extended criteria donors. Our analysis suggests that consent should be revisited as patients deteriorate or ameliorate on the waitlist, especially if in the form of ascites or HCC but not necessarily MELD score.

Endovascular Repair of a Descending Thoracic Aortic Aneurysm in a Pediatric Patient with Tuberous Sclerosis: A Case Report and Review of the Literature.

Aortic aneurysm in children is rare, but has been described in the tuberous sclerosis complex (TSC) population. While surgical repair has been utilized as the primary means of intervention, we present the first known case reporting exclusion of a descending thoracic aortic aneurysm with percutaneous covered stent implantation in a pediatric patient with TSC. A review of the literature is also included herein.

Cytotoxic effect of sodium hypochlorite (Lavanox 0.08%) and chlorhexidine gluconate (Irrisept 0.05%) on human osteoblasts.

PURPOSE: Soft tissue, bone and joint infections are severe complications in orthopedic and traumatological surgery. Lavanox (0.08% NaOCl) and Irrisept (0.05% chlorhexidine gluconate, CHG) are industrially produced antiseptic solutions commonly used in infection treatment. Regarding this clinical indication, the microbicidal effect is often investigated, but toxicity to osteoblasts has rarely been examined. This is important to decide whether these solutions should be used in septic situations in which bone healing must take place. The hypothesis of the present study is that NaOCl and CHG are cytotoxic to osteoblasts even after a short exposure time. METHODS: Human osteoblasts were isolated from donors with osteoarthritis during total knee and hip arthroplasty. Cells were cultivated and treated with both antiseptic solutions for 2, 5 and 10 min in different dilutions. Toxicity was quantified by counting cells, lactate dehydrogenase (LDH) expression, spectrophotometric quantification via XTT assay and FDA/PI fluorescence microscopy. RESULTS: Analyzing viable cells after treatment with both antiseptics showed a significant decrease in viable cells through LDH expression test, XTT assay, fluorescence microscopy and light microscopy, depending on concentration. The time dependence showed a trend to more cell death at longer exposure times, without significance. CONCLUSION: Toxic effects on osteoblasts were shown after treatment with 0.08% NaOCl and 0.05% CHG after an exposure time of 2 min which also was concentration dependent. There was no difference in cytotoxicity between both antiseptics. In conclusion, these antiseptic solutions may be used with caution in situations requiring bone healing. Trial registration number Local ethics committee registration number: 5176-07/16.

Vancomycin is toxic to human chondrocytes in vitro.

INTRODUCTION: Vancomycin powder (VP) is a well-established topical antibiotic used in spinal surgery to prevent surgical site infections. More recently its extension to hip and knee arthroplasty was introduced. The aim of this study was to examine toxic effects of VP on the viability of human chondrocytes. Our hypothesis was that VP damages human chondrocytes in vitro with increasing concentration and length of exposure. MATERIAL AND METHODS: Primary human chondrocytes were isolated and cultured from donated human knee joints. VP was added to these cultures with increasing concentrations (0-50 mg/ml) and length of exposure (0-336 h). Toxicity and viability were analyzed using LDH und XTT Elisa assays. Cell structure and determination of vital versus dead cells were visualized using light microscopy and fluorescence microscopy. RESULTS: Light microscopy and fluorescence microscopy visualized defect cell structures and cell death proportional to increasing dose and length of exposure to VP. The analysis of LDH activity data showed toxic effects on chondrocytes as early as 2,5 min after exposure to VP. XTT activity data revealed a significant toxic threshold of a VP concentration above 12.5 mg/ml. CONCLUSIONS: These results show that exposure to high VP concentrations yields to a damage of human chondrocytes in vitro. Chondrotoxicity is an immediate effect that is proportional to VP concentration. Therefore, the intraarticular use of high concentrations of vancomycin powder in the presence of native cartilage tissue must be considered critically.

ICBM-OCEAN: Processing Ultrahigh-Resolution Mass Spectrometry Data of Complex Molecular Mixtures.

Untargeted molecular analyses of complex mixtures are relevant for many fields of research, including geochemistry, pharmacology, and medicine. Ultrahigh-resolution mass spectrometry is one of the most powerful tools in this context. The availability of open scripts and online tools for specific data processing steps such as noise removal or molecular formula assignment is growing, but an integrative tool where all crucial steps are reproducibly evaluated and documented is lacking. We developed a novel, server-based tool (ICBM-OCEAN, Institute for Chemistry and Biology of the Marine Environment, Oldenburg-complex molecular mixtures, evaluation & analysis) that integrates published and novel approaches for standardized processing of ultrahigh-resolution mass spectrometry data of complex molecular mixtures. Different from published approaches, we offer diagnostic and validation tools for all relevant steps. Among other features, we included objective and reproducible reduction of noise and systematic errors, spectra recalibration and alignment, and identification of likeliest molecular formulas. With 15 chemical elements, the tool offers high flexibility in formula attribution. Alignment of mass spectra among different samples prior to molecular formula assignment improves mass error and facilitates molecular formula confirmation with the help of isotopologues. The online tool and the detailed instruction manual are freely accessible at www.icbm.de/icbm-ocean.

Good clinical and radiological results of total knee arthroplasty using varus valgus constrained or rotating hinge implants in ligamentous laxity.

PURPOSE: The optimal degree of constraint of a total knee arthroplasty for treatment of knee osteoarthritis with ligamentous laxity is under debate. While varus valgus constrained knees require a minimum level of ligamentous stability, rotating hinge knees can even be implanted if the collateral ligaments have been lost completely. It seems plausible that joint kinematics are determined by implant design in rotating hinge knees, whereas varus valgus constrained knees may be influenced by remaining stabilizers. This may result in more predictable clinical results of hinge knees. The hypothesis of the present study, therefore, was that stability and clinical outcome are better after total knee arthroplasty using rotating hinge knees than after using varus valgus constrained knees. METHODS: All patients who were treated using a mobile-bearing varus valgus constrained knee or a rotating hinge knee for treatment of end-stage osteoarthritis and ligamentous laxity were included. At follow-up, clinical scores were determined (WOMAC, VAS, KSS, FJS, Lysholm). Furthermore, body mass index, operating time, and postoperative complications were documented. Whole leg radiographs as well as patella axial radiographs were analyzed for implant alignment and patella tracking. RESULTS: Eighty-five patients were included in this retrospective study. Both groups showed an average range of motion of 113°. No significant difference between the two groups was observed for any of the scores recorded. In the rotating hinge knee group, a more precise tibia positioning in relation to the mechanical axis but also a significant lateralisation and tilting of the patella were seen, compared with the varus valgus constrained knee group. CONCLUSIONS: Rotating hinge knees did not perform better than mobile-bearing varus valgus constrained knees clinically. Both prosthesis types showed equally good clinical outcomes with regard to stability, mobility, satisfaction, pain and operating time. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

Patient Obesity Influences Pelvic Lift During Cup Insertion in Total Hip Arthroplasty Through a Lateral Transgluteal Approach in Supine Position.

BACKGROUND: Movement of the pelvis during implantation of total hip arthroplasty (THA) has a major influence on the positioning of the acetabular cup. Strong traction caused by retractors leads to iatrogenic pelvic lift and can thus be partly responsible for cup malpositioning. The objective of this study was to investigate such factors that influence pelvic lift. METHODS: The dynamic movement of the pelvis was measured during implantation of THA in 67 patients. This was done by measuring the acceleration using the SensorLog app on a smartphone. RESULTS: At its maximum, the pelvis was lifted by an average of 6.7°. When impacting the press-fit cup, the surgical side was raised by 4.4° compared with the time of skin incision. This lift at the time of cup implantation correlates significantly with the body mass index and the patient's abdominal and pelvic circumference. CONCLUSION: Every surgeon performing THA must be aware of the pelvic lift during an operation. Especially in patients with a high body mass index, a large abdominal circumference, or a large pelvic circumference, there is an increased risk of malpositioning of the acetabular cup. When impacting the cup, we recommend releasing the traction of the retractor, so that the pelvis can tilt back into its natural position, and thus, the anticipated cup positioning can be implemented as exactly as possible.

Community-Directed Vector Control to Accelerate Onchocerciasis Elimination.

Onchocerciasis, or river blindness, has historically been one of the most important causes of blindness worldwide, and a major cause of socio-economic disruption, particularly in sub-Saharan Africa. Its importance as a cause of morbidity and an impediment to economic development in some of the poorest countries in the world motivated the international community to implement several programs to control or eliminate this scourge. Initially, these involved reducing transmission of the causative agent Onchocerca volvulus through controlling the vector population. When ivermectin was found to be a very effective drug for treating onchocerciasis, the strategy shifted to mass drug administration (MDA) of endemic communities. In some countries, both vector control and ivermectin MDA have been used together. However, traditional vector control methods involve treating rivers in which the black fly vectors breed with insecticides, a process which is expensive, requires trained personnel to administer, and can be ecologically harmful. In this review, we discuss recent research into alternatives to riverine insecticide treatment, which are inexpensive, ecologically less harmful, and can be implemented by the affected communities themselves. These can dramatically reduce vector densities and, when combined with ivermectin MDA, can accelerate the time to elimination when compared to MDA alone.

What-if nature-based storm buffers on mitigating coastal erosion.

Creating ecosystem buffers in intertidal zones, such as seagrass meadows, has gained increasing attention as a nature-based solution for mitigating storm-driven coastal erosion. This study presents what-if scenarios using an integrated model framework to determine the effectiveness and strategies for planting seagrass to reduce coastal erosion. The framework comprises two levels of simulation packages. The first level is a regional-scale coupled hydrodynamic model that simulates the processes of a specific storm and provides boundary forces for the morphodynamic model XBeach to apply at the next level, which simulates nearshore morphological evolution. The framework is applied to the open coast of Norderney in the German Bight of the North Sea. We demonstrate that optimising the location and size of seagrass meadows is crucial to increase the efficiency of onshore sediment erosion mitigation. For a specific depth range, depending on the storm's intensity, the most significant reduction in erosion may not be achieved by starting the meadow at the depth that permits the largest meadow size. To maintain a significant coastal protection effect, seagrass density and stem height should be considered together, ensuring erosion reduction by at least 80 % compared to the unprotected coast. This study provides valuable insights for the design and implementation of seagrass transplantation as a nature-based solution, highlighting the importance of considering location, size, density, and stem height when using seagrass meadows for coastal protection.

Significant reduction of blackfly densities in persistent onchocerciasis area following pilot implementation of an environment friendly approach (Slash and Clear).

The effectiveness of the "Slash and Clear" method in reducing blackfly populations in low transmission areas is established, but its impact in high transmission settings with large rivers and dense vectors is yet to be proven. A community-based intervention study was conducted in the Mbam Valley, Centre Cameroon, involving two sites: Bayomen (control) and Biatsota (intervention). In each arm, baseline blackfly densities were collected over one year using the human landing method. The intervention consisted of destroying the trailing vegetation where blackflies breed. Blackfly densities were collected post-intervention to assess the impact of the intervention. Post-intervention data showed a 50.8% reduction in blackfly density in Biatsota (mean number of collected blackflies from 1936 to 953), while a reduction of 26.7% was observed in Bayomen (mean number of collected blackflies from 2418 to 1774). The reduction rate attributable to the intervention was 32.9%. Statistical analysis confirmed that the reduction in blackfly density was significantly greater in the intervention site. This study demonstrates the feasibility and significant impact of the "Slash and Clear" method in high transmission areas. However, further research is required to assess its long-term effects and determine how this strategy can be scaled up and sustained until onchocerciasis elimination is achieved.

Genetic Testing for Supravalvar Aortic Stenosis: What to Do When It Is Not Williams Syndrome.

BACKGROUND: We aimed to describe the frequency and yield of genetic testing in supravalvar aortic stenosis (SVAS) following negative evaluation for Williams-Beuren syndrome (WS). METHODS AND RESULTS: This retrospective cohort study included patients with SVAS at our institution who had a negative evaluation for WS from May 1991 to September 2021. SVAS was defined as (1) peak supravalvar velocity of ≥2 meters/second, (2) sinotubular junction or ascending aortic Z score <-2.0, or (3) sinotubular junction Z score <-1.5 with family history of SVAS. Patients with complex congenital heart disease, aortic valve disease as the primary condition, or only postoperative SVAS were excluded. Genetic testing and diagnoses were reported. Of 162 patients who were WS negative meeting inclusion criteria, 61 had genetic testing results available (38%). Chromosomal microarray had been performed in 44 of 61 and was nondiagnostic for non-WS causes of SVAS. Sequencing of 1 or more genes was performed in 47 of 61. Of these, 39 of 47 underwent ELN sequencing, 20 of 39 (51%) of whom had a diagnostic variant. Other diagnoses made by gene sequencing were Noonan syndrome (3 PTPN11, 1 RIT1), Alagille syndrome (3 JAG1), neurofibromatosis (1 NF1), and homozygous familial hypercholesterolemia (1 LDLR1). Overall, sequencing was diagnostic in 29 of 47 (62%). CONCLUSIONS: When WS is excluded, gene sequencing for SVAS is high yield, with the highest yield for the ELN gene. Therefore, we recommend gene sequencing using a multigene panel or exome analysis. Hypercholesterolemia can also be considered in individuals bearing the stigmata of this disease.

Effects of age on oxidative stress and locomotion in the pollinator, Megachile rotundata.

Despite numerous aging studies, the relationship between oxidative stress, aging, and decline in functions such as locomotion is still debated. Insects offer a promising model for analyzing the relationship between oxidative stress and aging, because they exhibit vast differences in lifespan that may be affected by the environment, social factors, levels of activity, and aging interventions. In this study, we explore the effects of aging on oxidative stress and locomotion using the pollinator, Megachile rotundata, a species that is very mobile and active in the adult stage. Across the adult lifespan of M. rotundata, we assessed changes in walking, flight, oxidative damage, and antioxidant defenses. Our results suggest that M. rotundata experience age-related declines in flight, but not walking. Additionally, we found that oxidative damage and antioxidant capacity initially increase with age and physical activity, but then levels are maintained. Overall, these data show that M. rotundata, like some other organisms, may not perfectly follow the free radical theory of aging.

Plain radiographic indices are reliable indicators for quantitative bone mineral density in male and female patients before total hip arthroplasty.

Osteoporosis is underdiagnosed in patients undergoing total hip arthroplasty (THA). Bone mineral density measurement by dual-energy X-ray absorptiometry (DXA) is the gold standard, but indices on plain hip radiographs also seemed to be reliable screening tools in female or Asian ethnicities in previous studies. Given the lack of knowledge about male patients and Caucasian ethnicities, this study was conducted to evaluate plane hip radiographic indices as a screening tool for osteopenia and osteoporosis in Caucasian female and also male patients before undergoing THA. A retrospective analysis of 216 elderly patients with pre-existing DXA before hip arthroplasty was performed and four indices were calculated on plain hip radiographs: Canal-Flare-Index (CFI), Canal-Calcar-Ratio (CCR), Canal-Bone-Ratio (CBR) 7 and 10 cm below the lesser trochanter. They were correlated with femoral neck DXA T-scores by Pearson's correlation and intraclass correlation coefficient, and a ROC analysis was performed. A total of 216 patients (49.5% male) were included. CBR-7 and -10 were highly correlated (p < 0.001) with femoral neck T-score in males (Pearson's correlation CBR-7 r = - 0.60, CBR-10 r = - 0.55) and females (r = - 0.74, r = - 0.77). CBR-7 and -10 also showed good diagnostic accuracy for osteoporosis in the ROC analysis in males (CBR-7: AUC = 0.75, threshold = 0.51; CBR-10: 0.63; 0.50) and females (CBR-7: AUC = 0.87, threshold = 0.55; CBR-10: 0.90; 0.54). Indices such as the Canal Bone Ratio (CBR) 7 or 10 cm below the lesser trochanter on plain hip radiographs are a good screening tool for osteopenia and osteoporosis on plain hip radiographs and can be used to initiate further diagnostics like the gold standard DXA. They differ between male and female patients.

Protocol for Establishing a Stakeholder Group for Primary Care Research into Cancer Using a Modified 7P Framework and an e-Delphi Process.

Introduction: Currently, no group specifically supports and coordinates primary care focused cancer research in Ireland. The aim of this project is to establish an inclusive stakeholder group for primary care focused cancer research in Ireland, to coordinate research efforts and build capacity in researchers and institutions. Methods: We will convene a stakeholder group, recruiting individuals with personal and professional experience of cancer care in a community setting. "Core stakeholders"-patients, clinicians, researchers, and policymakers-will attend regularly. Additional "specialist stakeholders", such as representatives of secondary care, private healthcare, health insurance, industry, cancer charities, and health research funders, will participate on an ad hoc basis. An e-Delphi consensus process will be used to assess the stakeholders' views on: (1) the relevance and importance of primary care focused cancer research; (2) the potential role and scope of the stakeholder group; (3) how best to engage with lived experience stakeholders and healthcare professionals affected by the research; (4) how to encourage the dissemination of results and the translation of findings into practice. Round 1 will be open-ended and will invite the independent suggestions of stakeholders; in Round 2 and 3, group members will vote on the inclusion of these suggestions in a position statement by the group, with consensus defined as ≥75% agreement. Discussion: The formation of a broad stakeholder group to support primary care focused cancer research will ensure research is relevant, patient centered, and more readily translated into practice. It is also hoped that the group will support capacity building and strategic planning in this important research space.

Clinical Outcomes and Associations With Radial to Femoral Crossover in ST-Elevation Myocardial Infarction.

Radial access during primary percutaneous coronary intervention is associated with reduced mortality and major bleeding compared with femoral access and is the recommended access site. Nevertheless, failure to secure radial access may necessitate crossover to femoral access. This study aimed to identify the associations with crossover from radial to femoral access in all comers with ST-elevation myocardial infarction and to compare the clinical outcomes with those patients who did not require crossover. From 2016 to 2021, a total of 1,202 patients presented to our institute with ST-elevation myocardial infarction. Associations, clinical outcomes, and independent predictors of crossover from radial to femoral access were identified. From 1,202 patients, radial access was used in 1,138 patients (94.7%) and crossover to femoral access occurred in 64 patients (5.3%). Patients who required crossover to femoral access had higher rates of access site complications and longer length of stay in the hospital. Inpatient mortality was higher in the group requiring a crossover. This study identified 3 independent predictors of crossover from radial to femoral access in primary percutaneous coronary intervention: cardiogenic shock, cardiac arrest before arrival at the catheterization laboratory, and previous coronary artery bypass grafting. Biochemical infarct size and peak creatinine was also found to be higher in those requiring crossover. In conclusion, crossover in this study portended an increased rate of access site complications, greatly prolonged length of stay, and a significantly higher risk of death.

DSC MRI in the human brain using deoxyhemoglobin and gadolinium-Simulations and validations at 3T.

Introduction: Dynamic susceptibility contrast (DSC) MRI allows clinicians to determine perfusion parameters in the brain, such as cerebral blood flow, cerebral blood volume, and mean transit time. To enable quantification, susceptibility changes can be induced using gadolinium (Gd) or deoxyhemoglobin (dOHb), the latter just recently introduced as a contrast agent in DSC. Previous investigations found that experimental parameters and analysis choices, such as the susceptibility amplitude and partial volume, affect perfusion quantification. However, the accuracy and precision of DSC MRI has not been systematically investigated, particularly in the lower susceptibility range. Methods: In this study, we compared perfusion values determined using Gd with values determined using a contrast agent with a lower susceptibility-dOHb-under different physiological conditions, such as varying the baseline blood oxygenation and/or magnitude of hypoxic bolus, by utilizing numerical simulations and conducting experiments on healthy subjects at 3T. The simulation framework we developed for DSC incorporates MRI signal contributions from intravascular and extravascular proton spins in arterial, venous, and cerebral tissue voxels. This framework allowed us to model the MRI signal in response to both Gd and dOHb. Results and discussion: We found, both in the experimental results and simulations, that a reduced intravascular volume of the selected arterial voxel, reduced baseline oxygen saturation, greater susceptibility of applied contrast agent (Gd vs. dOHb), and/or larger magnitude of applied hypoxic bolus reduces the overestimation and increases precision of cerebral blood volume and flow. As well, we found that normalizing tissue to venous rather than arterial signal increases the accuracy of perfusion quantification across experimental paradigms. Furthermore, we found that shortening the bolus duration increases the accuracy and reduces the calculated values of mean transit time. In summary, we experimentally uncovered an array of perfusion quantification dependencies, which agreed with the simulation framework predictions, using a wider range of susceptibility values than previously investigated. We argue for caution when comparing absolute and relative perfusion values within and across subjects obtained from a standard DSC MRI analysis, particularly when employing different experimental paradigms and contrast agents.