Citations

Abstract Background Computed tomography (CT) is an essential imaging modality for disease diagnosis, treatment efficacy, and image‐based guidance of various medical procedures. The locally deposited radiation dose in tissues, as estimated by the computed tomography dose index (CTDI), can vary considerably across exposures delivered by CT scanners from different vendors, even if the scans are performed using similar technique factors, such as tube potential and tube current. The volumetric CTDI (CTDI vol ) is a common dose metric that reports an average radiation dose (in mGy) delivered to a specific volume within a test phantom. The CTDI vol is important in dosimetry applications as the organ absorbed dose within the patient has been shown to scale in near‐linear proportion, creating a basis for comparing organ doses across different scan protocols and scanner models. Purpose To develop a database of tube current‐time product (mAs) normalized CTDI vol values for currently utilized CT scanner models for each of the four primary CT vendors for use in the MIRDct organ dosimetry software available at MIRDsoft.org. This data forms the basis of the MIRDct code, which reports organ doses across a range of computational phantoms based upon axial organ dose coefficient libraries generated through Monte Carlo radiation transport for a reference CT scanner. Organ doses delivered by alternate CT scanner vendors and models may then be reported using ratios of normalized CTDI vol values under similar technique factors. Methods Scanners were selected from four major CT manufacturers: Philips Healthcare, GE Healthcare, Canon Medical Systems, and Siemens Healthineers. Technique parameters were also selected for each scanner that closely matched values used in the generation of an equivalent CT source term (small to large bowtie filters; 80–140‐kVp tube voltage; and 10‐mm to 40‐mm beam collimation). For each scanner chosen, the appropriate technique factors and protocols were selected, and the console‐reported CTDI vol values were recorded and normalized to a set value of 100 mAs. The normalized CTDI vol data collected for use within the MIRDct code were analyzed for noticeable patterns, features, and trends, and were compared to similar normalized CTDI vol datasets used within the National Cancer Institute NCICT software and the Virtual Phantoms, Inc. VirtualDose software. Results For all given CT scanner and technique factor combinations, there was strong agreement in normalized CTDI vol values across all three codes: between 0% and 12% difference for the compared scanners. Ratios of CTDI vol values for various CT scanner vendors and models to the corresponding CTDI vol values for the MIRDct reference scanner (Cannon Aquilion One Genesis) were also compared on the basis of either the 16‐cm head PMMA phantom or the 32‐cm body PMMA phantom. The mean quotient of these normalized CTDI vol ratios (head ratios to body ratios) was found to be approximately 1.06, and thus either ratio may be applied in reporting patient organ dose by MIRDct. Conclusions A database of normalized CTDI vol (mGy/100 mAs) was created for 17 models of CT scanners from four manufacturers at varying tube potentials, collimations, x‐ray bowtie filters, and phantom sizes for use in the MIRDct software.

Abstract Background Artificial intelligence (AI) augmented laboratory tests can improve quality, efficiency, cost-effectiveness, and staff satisfaction. However, the clinical success of these tests can introduce unforeseen challenges for model retraining. This study describes the discovery of an “AI label feedback loop” in a clinically implemented AI-augmented kidney stone composition test. Methods An AI-augmented kidney stone composition test (V1) has been previously deployed for clinical kidney stone characterization. After several years of clinical use, a retrained model (V2) was developed using 6 times more data. Model performance of both V1 and V2 were evaluated across 3 datasets: a recent production validation (hold-out) set (mostly AI-influenced labels), the original V1 validation set (pre-AI, entirely human-labeled), and a subset of recent cases with exclusively human-generated or human-corrected labels. Results V2 demonstrated a 10% lower concordance rate than V1 when evaluated on the recent production hold-out set, despite a much larger training dataset. Performance between V1 and V2 was similar when applied to the pre-AI validation set. Notably, V2 outperformed V1 on the recent subset of cases with human-only or human-corrected labels, particularly for less-common stone types. These findings revealed an AI label feedback loop, confounding retraining and evaluation. Conclusions The integration of AI into clinical practice can potentially influence reported test results, complicating the development and evaluation of future models. To mitigate AI label feedback loops, ongoing human annotation and careful validation set construction are essential. These strategies can ensure reliable performance assessment and support the safe evolution of clinical AI systems.

Abstract Background Individuals living in socioeconomically disadvantaged areas are disproportionately affected by dementia. However, the pathway leading from neighbourhood deprivation to cognitive symptoms is not well understood. To test our hypothesis that this relationship is associated with cerebral small vessel disease (SVD), we examined (1) whether neighbourhood deprivation related to midlife SVD burden and cognition, and (2) whether these links can be explained by modifiable lifestyle risk factors. Method In this multi‐centre cross‐sectional study, 514 cognitively healthy midlife participants aged 40‐59 years (median 52 years, 64.6% female) underwent clinical assessment and 3T MRI. Postcode data were used to obtain national indices of neighbourhood deprivation. To quantify SVD, we assessed white matter hyperintensities (WMH), perivascular spaces, cerebral microbleeds, and lacunes. Cognition was assessed using the Computerized Assessment of Information Processing (COGNITO) battery. Lifestyle risk factors were evaluated based on clinical data. Using multivariate statistics like structural equation modelling (SEM) and canonical correlation analysis (CCA), we examined associations between these constructs both globally and at the item‐level (i.e., distinction between domains of cognition/deprivation), to shed light on specific domains that could inform targeted prevention strategies. Result Neighbourhood deprivation related to greater prevalence of lifestyle risk factors ( r = 0.36, p < .001), greater SVD burden (b=0.18, p = .01; Figure 1), and greater cognitive impairment ( r = 0.36, p < .001), independent of educational attainment, sex, and age. These links with neighbourhood deprivation were largely driven by lifestyle factors relating to vascular health (sleep, physical activity, obesity, hypertension) (Figure 2), and cognitive deficits consistent with SVD (processing speed, visuospatial) (Figure 3). Residents of deprived neighbourhoods displayed greater prevalence of lifestyle risk factors, except alcohol consumption. Lower cognitive scores were most closely associated with deprivation domains of Crime and Living Environment (Figure 3). The DEPRIVATION→SVD path was mediated by lifestyle risk factors (z=2.57, p = .010), and the DEPRIVATION→COGNITION path was mediated by SVD (z=‐2.14, p = .032) (global SVD & hypertensive subtype, but not CAA‐SVD). Conclusion The pathway linking neighbourhood disadvantage to cognitive impairment at midlife is influenced by vascular risk factors and cerebrovascular burden. Tailored strategies could promote resilience against dementia by promoting health behaviours aligned with the community's unique needs.

PURPOSE The feasibility of Oncotype DX Breast Recurrence Score testing on diagnostic core needle biopsy (CNB) samples has been demonstrated through analysis of a large central laboratory experience. However, concordance with paired samples from the same primary breast tumor has not been comprehensively evaluated. The primary objective of this study was to determine the degree of concordance of Recurrence Score (RS) results between paired CNB and surgical excision (SE) specimens from the same untreated primary breast tumor of patients with early-stage, hormone receptor–positive, human epidermal growth factor receptor 2–negative invasive breast cancer. MATERIALS AND METHODS Patients with a clinical RS result on either a CNB or SE specimen were included. Lin concordance correlation coefficient (CCC) with 95% CIs was estimated to assess agreement of continuous RS results between paired samples. Cohen Kappa with 95% CIs was used to evaluate categorical RS result concordance. RESULTS A total of 134 patients were identified with paired CNB and SE specimens. The median age was 62 years (range, 33-99; 23 patients [17%] were age ≤50 years v 111 [83%] age >50 years). The mean RS results were 15.6 (range, 0-56) for CNB and 16.6 (range, 0-59) for SE ( P = .003), with no statistically significant differences in RS categories. Agreement between continuous RS results from paired samples was strong, with a Lin CCC of 0.86 (95% CI, 0.80 to 0.90). The overall percent agreement in RS categories was 91.8% (95% CI, 87.1 to 96.4). Categorical agreement was further supported by a Cohen Kappa statistic of 0.64 (95% CI, 0.44 to 0.83), indicating substantial agreement between CNB and SE specimens. CONCLUSION The results of this study demonstrate high concordance of RS results between paired samples, which supports the use of CNB for Oncotype DX testing.

Background: Among the 1.5 million cases of cutaneous squamous cell carcinoma (cSCC) diagnosed annually in the United States, a subset of aggressive tumors recur or metastasize. Treatment options include total margin-controlled surgery, such as Mohs micrographic surgery or other forms of peripheral and deep en face margin assessment (MMS/PDEMA), and standard excision with postoperative vertical section margin assessment (SEVMA). NCCN Guidelines recommend MMS/PDEMA for the management of cSCC classified as very high risk based on NCCN risk stratification criteria. This study aims to validate the recommendation of MMS/PDEMA as the preferred surgical approach for NCCN very high-risk cSCCs, using data from a multicenter, multinational cohort. Methods: A multicenter cohort study was conducted across 12 sites, including 10 in the United States, 1 in Spain, and 1 in Brazil, comprising 2,752 primary NCCN very high-risk cSCCs treated with MMS/PDEMA or SEVMA. Propensity score–weighted analysis was used to balance baseline characteristics. Outcomes included local recurrence (LR), nodal metastasis (NM), distant metastasis (DM), and disease-specific death (DSD). Results: After balancing baseline characteristics, SEVMA was associated with a 2-fold higher rate of poor outcomes, including recurrence, metastasis, and DSD, compared with MMS/PDEMA. The 3-year cumulative incidence of poor outcomes was higher for SEVMA: LR (12.5% vs 5.9%), NM (11.6% vs 6.0%), DM (4.3% vs 1.9%), and DSD (6.2% vs 3.3%). Conclusions: This study supports the NCCN recommendation of MMS/PDEMA for NCCN very high-risk cSCC, showing reduced recurrence, metastasis, and cSCC-specific mortality compared with SEVMA.

Background The hemodynamic profile and remodeling patterns of paradoxical low‐flow, low‐gradient aortic stenosis are well understood. However, some patients with severe aortic stenosis exhibit eccentric remodeling with enlarged left ventricular cavities, enabling a normal flow, low ejection fraction ( NF ‐ LEF ) phenotype. We assessed the prevalence, hemodynamic characteristics, and post‐transcatheter aortic valve implantation outcomes of NF ‐ LEF . Methods In this substudy of the COMPARE‐TAVI 1 trial, 979 patients undergoing transfemoral transcatheter aortic valve implantation were stratified by left ventricular ejection fraction (LVEF) (< or ≥50%) and stroke volume index (< or ≥35 mL/m 2 ) into 4 groups: normal flow, normal LVEF, NF‐LEF, low flow, normal ejection fraction, and low flow, low ejection fraction. Results NF‐LEF was observed in 10.7% of patients. Reduced LVEF was associated with previous myocardial infarction, pacemakers, New York Heart Association class >2, atrial fibrillation, moderate or worse mitral regurgitation, and larger left ventricular cavities ( P <0.001) with eccentric hypertrophy ( P =0.004). Compared with low‐flow, low‐ejection fraction, patients with NF‐LEF more frequently had moderate or worse aortic regurgitation ( P =0.007), whereas low flow, low ejection fraction showed poorer diastolic indices, suggesting diastolic dysfunction with high left ventricular filling pressures. Patients with low flow, normal ejection fraction were the most symptomatic and showed less improvement in 6‐minute walk distance at 1 year compared with normal flow, normal ejection fraction. During follow‐up, both low‐flow groups demonstrated significant increases in stroke volume index ( P <0.001), whereas LVEF also improved among patients with reduced LVEF ( P <0.001). Conclusions NF‐LEF is a prevalent aortic stenosis phenotype characterized by preserved flow despite reduced LVEF, likely driven by eccentric remodeling with moderate or worse aortic regurgitation and more favorable diastolic properties, with similar survival and time‐to‐event outcomes across phenotypes after transcatheter aortic valve implantation at long‐term follow‐up. Despite higher comorbidity burdens, patients with NF‐LEF showed functional and clinical improvements comparable with normal flow, normal ejection fraction, indicating a severe aortic stenosis phenotype.

Background The past two decades have witnessed tremendous growth in the appreciation and treatment of sacroiliac joint (SIJ) complex pain, including anatomical dissections that shed light on innervation, an appreciation for the contribution of extra-articular components to SIJ complex pain, the advent of radiofrequency ablation (RFA) and a host of minimally-invasive surgical techniques. Yet, there is no standardization of diagnosis and treatment paradigms. Methods In February 2023, the Boards of Directors for the American Academy of Pain Medicine (AAPM) and American Society of Regional Anesthesia & Pain Medicine (ASRA-PM) approved the development of multispecialty guidelines on SIJ complex pain. Thirty partner organizations with clinical and scientific interests in SIJ complex pain were identified, and formal letters of request-for-participation were sent to each, along with a request for nominees to serve on the committee. Twenty five organizations agreed to participate in addition to the Departments of Defense and Veterans Affairs. A steering committee developed 21 questions, which spanned criteria for diagnosis, non-interventional and interventional treatments including surgery, technical parameters on how to optimize results, and what constitutes positive outcomes. Questions were methodically assigned to specialized modules comprising 4–5 members with complementary expertise, who collaborated with the Subcommittee Lead and one of three Committee Chairs to develop preliminary drafts. Following thorough revisions, these drafts were subsequently submitted to the full committee for comprehensive review. A modified Delphi method was used in which the answers to questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was achieved. During a committee meeting before commencement, it was agreed that recommendations would be noted when there was >50% agreement among committee members, but that a formal recommendation would require ≥75% consensus. Results Twenty-one organizations formally endorsed the guidelines. The American Society of Anesthesiologists, and American Academy of Physical Medicine & Rehabilitation, and the North American Spine Society affirmed the benefit of the guidelines but did not officially endorse them. The American Academy of Neurology declined to affirm the benefit of the guidelines citing ‘lack of relevance to their membership.’ Per policies, while the Departments of Defense and Veterans Affairs did not formally review the guidelines for endorsement, their representatives approved them. In addition to being endorsed or the benefit affirmed by all voting organizations, complete consensus from committee members was obtained on all 21 questions. On two recommendations, there were dissensions from three societies who thought that selecting patients for sacral lateral branch RFA and minimally-invasive fusion should be based on ≥75% relief from two blocks instead of at least 50% relief from a single block before RFA, and greater than 50% pain relief with documented functional improvement after a single block before fusion. One additional society (Latin American Society of Regional Anesthesia) abstained on the statement that the evidence is stronger for extra-articular than intra-articular injections. The committee found that a battery of physical exam tests has reasonable sensitivity, but lower specificity, for identifying intra-articular but not extra-articular pain, with negative tests having greater predictive value than positive ones. Intra-articular injections have diagnostic validity for SIJ intra-articular, but not extra-articular, pain. There is unclear or negative evidence for imaging. The prevalence rates of intra-articular and extra-articular pathology are comparable, with both intra- and extra-articular steroid injections providing at least 4 weeks of relief in well-selected patients. However, the evidence is slightly stronger for extra-articular corticosteroid injections to provide short-term relief. The evidence base for non-interventional therapies is indirect, extrapolated mostly from low back pain studies. There is weak evidence supporting dextrose-based prolotherapy and platelet-rich plasma to provide at least 3 months of pain relief. There is strong evidence for sacral lateral branch RFA to provide relief for at least 6 months in individuals with extra-articular pathology, with face validity and indirect evidence from randomized trials supporting sacral lateral branch blocks as a prognostic tool. There is stronger evidence for larger lesions or more aggressive lesioning strategies than for less stringent techniques. There is weak evidence to support non-steroidal anti-inflammatory drugs to prevent neuritis after RFA, and in most cases anticoagulation does not require cessation in the periprocedural period. With an aggressive lesioning strategy, sensory stimulation provides minimal therapeutic benefit, with weak, extrapolated evidence that motor stimulation can provide safety benefit. The cut-off to designate diagnostic or prognostic blocks as positive is most commonly set at 50%, with higher values not shown to improve outcomes for more definitive procedures; for therapeutic treatment outcomes, the evidence supports a lower threshold of ≥30% pain relief or meaningful benefit on non-pain outcomes (eg, opioid cessation) for designation of a positive response. For carefully selected patients with intra-articular SIJ complex pain based on controlled blocks who have failed conservative therapies, there is weak or very weak evidence that minimally invasive SIJ fusion can provide benefit for at least one year. Conclusions SIJ complex pain remains an underappreciated source of chronic low back pain, affecting between 15% and 30% of patients with axial pain predominantly below L5. Answers to many questions were limited by low-quality evidence, indicating the need for better research. SIJ complex pain is a multifarious condition (ie, pain can be from different portions of both the intra- and extra-articular components of the joint) for which an interdisciplinary, multimodal treatment plan can optimize treatment outcomes.