Diagnostic Impact Research Articles

Age-stratified deep learning model for thyroid tumor classification: a multicenter diagnostic study.

Thyroid cancer, the only cancer that uses age as a specific predictor of survival, is increasing in incidence, yet it has a low mortality rate, which can lead to overdiagnosis and overtreatment. We developed an age-stratified deep learning (DL) model (hereafter, ASMCNet) for classifying thyroid nodules and aimed to investigate the effect of age stratification on the accuracy of a DL model, exploring how ASMCNet can help radiologists improve diagnostic performance and avoid unnecessary biopsies. In this retrospective study, we used ultrasound images from three hospitals, a total of 10,391 images of 5934 patients were used for training, validation, and testing. The performance of ASMCNet was compared with that of model-trained non-age-stratified radiologists with different experience levels on the test data set with the DeLong method. The area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity of ASMCNet were 0.906, 86.1%, and 85.1%, respectively, which exceeded those of model-trained non-age-stratified (0.867, 83.2%, and 75.5%, respectively; p < 0.001) and higher than all of the radiologists (p < 0.001). Reader studies show that radiologists' performances are improved when assisted by the explaining heatmaps (p < 0.001). Our study demonstrates that age stratification based on DL can further improve the performance of thyroid tumor classification models, which also suggests that age is an important factor in the diagnosis of thyroid tumors. The ASMCNet model shows promising clinical applicability and can assist radiologists in improving diagnostic accuracy. Question Age is crucial for differentiated thyroid carcinoma (DTC) prognosis, yet its diagnostic impact lacks research. Findings Adding age stratification to DL models can further improve the accuracy of thyroid nodule diagnosis. Clinical relevance Age-stratified multimodal classification network is a reliable tool used to help radiologists diagnose thyroid nodules, and integrating it into clinical practice can improve diagnostic accuracy and reduce unnecessary biopsies or treatments.

The clinical utility of tissue polymerase chain reaction, tissue culture and tissue histology in blood culture-negative infective endocarditis in South Africa – insights from the Groote Schuur Hospital Infective Endocarditis Registry

Background. Infective endocarditis (IE) poses significant diagnostic and therapeutic challenges, especially in cases of blood culture-negative infective endocarditis (BCNIE). Among patients undergoing surgery for IE, valve tissue may be evaluated for additional microbiological information by performing a broad-range 16S rDNA polymerase chain reaction (PCR) test, tissue culture and tissue histopathology. In patients with BCNIE, these diagnostic tests may identify the causative agents, guide further clinical management and improve local IE-related epidemiological data. The clinical utility of additional analysis of explanted tissue in a local South African (SA) setting has yet to be described. Objectives. To assess the clinical utility of performing PCR, culture and histopathology on the tissue of surgically explanted valves in BCNIE patients in an SA public sector hospital. We assess their diagnostic yield and treatment impact in a cohort of BCNIE patients treated with empirical antibiotic regimens. Methods. We analysed data from the Groote Schuur Hospital (GSH) Infective Endocarditis Registry, a prospective observational study of adult patients with infective endocarditis. Participants for this analysis were selected based on clinical and pathological criteria for IE and negative blood cultures. All participants were treated between January 2017 and March 2021. Results. During the study period, we identified 165 IE cases, 57 (34.5%) of which were blood-culture negative. BCNIE patients had a mean (standard deviation) age of 40.2 (13.4) years, and 41 (71.9%) were male. Twenty-seven of the 57 BCNIE patients underwent cardiac surgery and had tissue analysis performed. Tissue PCR identified an aetiological agent in 17/27 (63%) cases, with Bartonella spp. (12/27, 44%) being the most common organism. Tissue culture was positive in 3/27 (11%) cases, but the organisms identified were thought to reflect sample contamination. Tissue histopathology was performed in 22/27 (81.5%) cases and provided macroscopic confirmation of IE, but did not identify any specific organisms in any of the specimens. Only a small subset of the overall BCNIE cohort (11/57 (19.3%)) had serum serology for Bartonella spp. and Coxiella spp. performed, and 5/11 (45.5%) were positive for Bartonella spp. There was a 100% concordance rate between positive serum serology and tissue PCR. Tissue PCR impacted the antimicrobial regimen in 20/27 (74%) cases. Tissue culture and tissue histopathology did not influence antibiotic regimens in any patients. Conclusion. In this single-centre study, perioperative serum serological testing was underutilised in BCNIE. Tissue PCR was valuable in determining the aetiology of BCNIE, and influenced management. Tissue culture and histopathology had a poor yield and added little value in identifying the microbiological cause of BCNIE. Finally, the most common BCNIE causative organism identified by additional non-culture testing in our setting is Bartonella spp.

FAP-targeted PET/CT imaging in patients with breast cancer from a prospective bi-center study: insights into diagnosis and clinic management.

To evaluate the diagnostic accuracy and clinical impact of fibroblast activation protein (FAP)-targeted PET/CT imaging in primary and metastatic breast cancer and compare the results with those of standard-of-care imaging (SCI) and [18F]FDG PET/CT. We prospectively analyzed patients with diagnosed or suspected breast cancer who underwent concomitant FAP-targeted PET/CT (radiotracers including either [68Ga]Ga-FAPI-46 or [18F]FAPI-42) and [18F]FDG PET/CT scans from June 2020 to January 2024 at two medical centers. Breast ultrasound (US) imaging was performed in all treatment-naïve patients as SCI. The SUVmax, tumor-to-background ratio (TBR), lesion detection rate, and tumor-node-metastasis (TNM) classifications between FAP-targeted and [18F]FDG PET/CT were evaluated and compared. Sixty-one female patients (median age, 52 y; range, 28-82 y) were included. Among them, 23 patients underwent evaluation for a definitive diagnosis of suspected breast lesions, 15 underwent initial staging, and 23 were evaluated for the detection of recurrence. The sensitivities of breast US, [18F]FDG, and FAP-targeted PET/CT for detecting primary breast tumors were 82%, 79%, and 100%, respectively. Regarding the diagnosis of recurrent/metastatic lesions, the lesion-based detection rate of FAP-targeted PET/CT was significantly higher than that of [18F]FDG, which included local and regional recurrence, neck lymph node (LN), abdomen LN, bone, and liver metastases. Compared with [18F]FDG PET/CT, FAP-targeted PET/CT altered thirteen patients' TNM staging/restaging (13/59, 22%) and nine patients' clinical management (9/59, 15%). Compared to SCI, FAPI changed fourteen patients' TNM staging/re-staging (14/59, 24%) and eleven patients' therapeutic regimens(11/59, 19%). There was no significant association between FAPI-derived SUVmax and receptor status/histologic type in both primary and metastatic lesions. FAP-targeted PET/CT was superior to [18F]FDG in diagnosing primary and metastatic breast cancer, with higher radiotracer uptake and TBR, especially in the detection of primary/recurrent tumors, abdominal LN metastases, liver, and bone metastases. FAP-targeted PET/CT is superior to [18F]FDG and SCI in TNM staging and may improve tumor staging, recurrence detection, and implementation of necessary treatment modifications.

P-1606. Utilizing Diagnostic Stewardship to Help Increase the Yield and Clinical Value of Broad Range PCR Testing at a Tertiary Children’s Hospital

Abstract Background Broad range PCR testing (BR-PCR) in various clinical samples has the ability to provide timely diagnoses that cannot always be made through conventional testing (CT), yet its diagnostic yield and clinical impact have been variable, especially by specimen type. As such, we developed an ID-physician led diagnostic stewardship approval protocol to help optimize test usage. Methods We conducted a single-center, retrospective pre/post study to assess the impact of an ID-led diagnostic stewardship approval protocol for BR-PCR testing. All clinical specimen types obtained for BR-PCR at Riley Hospital for Children were evaluated between 10/1/2019 to 4/30/2022 (pre-intervention) and 5/1/2022-12/31/2023 (post-intervention). Clinical relevancy of BR-PCR results was determined after review from two ID physician experts and compared between the two time periods, along with clinical impact and overall cost savings. Results A total of 931 BR-PCR tests were sent from 238 specimens collected from 175 patients in the pre-intervention period, while 208 BR-PCR tests were sent from 65 specimens collected from 65 patients in the post-intervention period. Clinical relevancy of results was determined to be 30.7% and 56.9% for pre-and post-intervention periods, respectively (p&amp;lt; 0.001). 23.1% of post intervention results led to a change in clinical management, compared to 12.6% in the pre-intervention period (p=0.035). Bronchial lavage (BAL) was the most common specimen type with 52.9% of results being clinically relevant post-intervention, compared to 29.6% in the pre-intervention period; p=0.068). Results that led to a clinical change in management were also slightly higher but non-significant for BALs post-intervention (11.8% vs 9.9% pre intervention; p=0.816). Overall cost savings post-intervention was estimated to be $200,000. Conclusion Use of an ID-physician led diagnostic stewardship approval protocol led to an overall improvement in clinical utility for BR-PCR testing at our institution and was influenced by specimen type. Prospective, multi-center studies are needed to determine which specimen types, diagnoses, and potential diagnostic stewardship measures will help increase the yield and clinical value of BR-PCR testing. Disclosures Jack G. Schneider, MD, MiraVista Diagnostics: Advisor/Consultant

Assessing the diagnostic potential of SATB2 and β-catenin as biomarkers and therapeutic targets in pancreatic ductal adenocarcinoma

IntroductionPancreatic ductal adenocarcinoma (PDAC) is associated with poor prognosis. The roles of the transcription factor special AT-rich binding protein-2 (SATB2) and β-catenin in PDAC have been a subject of controversy. We aimed to assess the diagnostic and prognostic impact of SATB2 and β-catenin in PDAC.MethodsWe analyzed 44 paraffin-embedded tissue blocks along with corresponding blood and pancreatic tissues. We evaluated SATB2 expression using immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA). β-catenin was assessed using IHC and real-time polymerase chain reaction (qPCR).ResultsHigh SATB2 expression and low β-catenin expression were associated with a poor prognosis in PDAC, including advanced pathological tumor stage (pT-stage), pathological lymph node stage (pN-stage), and TNM stage. We found a positive correlation between SATB2 expression assessed by IHC and the concentration of SATB2 in both serum and tissue samples measured by ELISA. We observed a positive correlation between β-catenin expression assessed by IHC and β-catenin levels measured by qPCR.ConclusionsSATB2 and β-catenin could provide valuable insights into the development of pancreatic cancer, and targeting them may be beneficial for the prevention and treatment of PDAC. The levels of SATB2 in serum show promise for the diagnosis and tumor invasion of pancreatic cancer.

Association of echocardiographic radiomics-based features with cardiotoxicity effect in breast cancer patients from the CARDIOCARE project

Abstract Introduction Improvements in breast cancer (BC) treatment including chemotherapy have increased significantly the BC survivors. However, higher BC survival rates have been compromised by life-threatening collateral toxic effects. Effects such as cardiomyopathy and heart failure, described as cardiotoxicity, have become main causes of comorbidity and mortality, having a great impact on patients’ quality of life. Purpose Leverage radiomics-based analysis to explore innovative, non-invasive echocardiography biomarkers that can associate with cardiotoxicity. Method A cohort of 28 prospective patients (above 60 years old, 10 cardiotoxic) of the EU-funded CARDIOCARE project [1] undergoing cardiotoxic antineoplasmatic therapy was utilized to investigate potential association between imaging features calculated from the end diastolic (ED) and end systolic (ES) apical 4- and 2-chamber views and patients’ cardiotoxicity status as defined by the project's cardiologists using imaging data (Left Ventricle Ejection Fraction , Global Longitudinal Strain) and blood test markers (high sensitive Troponin I and Nt-pro-Bnp). Imaging data were collected at baseline visit (start of the treatment) and 3 months after. A pre-trained deep neural network [2] was initially utilized to automatically segment the myocardium (MY) and the left ventricle (LV) from the ED and ES 4- and 2-chamber static views both at baseline (T0) and 3-month follow-up (T1). More than 1500 imaging features were calculated from all images of the MY and LV using radiomics, a state-of-the-art technique to elicit hidden image patterns using histogram, shape and textural features. Apart from radiomics at T0 and T1, time-dependent features (delta-radiomics) were also provided as the relative change in radiomics values between T0 and T1, aiming to reveal potential changes at the MY and LV areas through treatment. Cardiotoxicity status was defined at T1. Results A univariate analysis using the Wilcoxon rank-sum test identified a subset of 40 radiomics features (20 delta-radiomics and 20 from T1) to be considered statistically significant (p-value&amp;lt;0.05) in differentiating cardiotoxic from non-cardiotoxic patients. Histogram and shape-based characteristics showed no association with cardiotoxicity status. Additionally, radiomics-based features at T0 were not statistically significant. All significant features corresponded to textural properties of the MY, indicating that the heterogeneity of the MY can be a significant factor for cardiotoxicity. 17 out of 20 T1 features were calculated from the 4-chamber view of the MY (19/20 from the ED). 15 delta-radiomics textural features were extracted from the 2-chamber view of the MY region at the ES. Conclusion Heterogeneity of the myocardium quantified by radiomics has potential diagnostic impact in assessing cardiotoxicity response, paving the way for the development of image-based risk stratification models for the early detection of cardiac toxicity.

Tumor localization strategies of multi-cancer early detection tests: a quantitative assessment.

Multi-cancer early detection (MCED) tests may expand cancer screening. Characterizing diagnostic resolution approaches following positive MCED tests is critical. Two trials employed distinct resolution approaches: a molecular signal to predict tissue of origin (TOO) and an imaging-based diagnostic strategy. This modeling study characterizes diagnostic journeys and impact in a hypothetical population of average risk MCED eligible patients. A mathematical expression for diagnostic burden was derived using positive predictive value (PPV), molecular TOO localization accuracy, and numbers of procedures associated with each diagnostic outcome. Imaging-based and molecular TOO-informed strategies were compared. Excess lifetime cancer risk due to futile radiation exposure was estimated using organ-specific diagnostic imaging radiation doses. Across all PPVs and localization performances, a molecular TOO strategy resulted in a higher diagnostic burden: 3.6 procedures [SD 0.445] vs 2.6 procedures [SD 0.100] for the imaging strategy. Estimated diagnostic burden was higher for molecular TOO in 95.5% of all PPV and TOO accuracy combinations; ≥79% PPV and 90% accuracy would be required for a molecular TOO-informed strategy to be less burdensome than imaging. The maximum rate of excess cancer incidence from radiation exposure for MCED false positive results (individuals aged 50-84) was 64.6/100,000 (annual testing, 99% specificity), 48.5/100,000 (biennial testing, 98.5% specificity), and 64.6/100,000 (biennial testing, 98% specificity). An imaging-based diagnostic strategy is more efficient than a molecular TOO-informed approach across almost all PPV and TOO accuracy combinations. The use of an imaging-based approach for cancer localization can be efficient and low-risk compared to a molecular-informed approach.

The Impact of Rapid Molecular Diagnostics for Influenza on Antibiotic Stewardship in the Emergency Department—An Observational Retrospective Study

Objective: The clinical diagnosis of respiratory tract infections (RTIs) may result in unnecessary antibiotic treatment due to clinical exams’ low sensitivity and specificity to differentiate viral from bacterial infections and costly diagnostic work-ups. Unnecessary antibiotic consumption drives antibiotic resistance. We explored whether a rapid influenza-specific polymerase chain reaction (PCR) assay reduced antibiotic use in an emergency room before the COVID-19 pandemic. Methods: We conducted an observational retrospective study of patients with RTI symptoms treated in the ER of the University Hospital Basel from September 2014 to June 2015. We evaluated the impact of rapid diagnostic results, such as an influenza-specific PCR, blood sample results, and radiological imaging, on antibiotic prescription rates. Patient-related confounding factors were included since a patient’s clinical condition affects doctors’ clinical decision-making. Results: We included 607 patients with RTIs, tested with PCR for influenza A or B. Logistic regression showed that the odds ratio (OR) of being treated with antibiotics was significantly reduced by more than two-thirds in patients with a positive influenza PCR result (OR = 0.37; 95% CI, 0.22–0.59; p &lt; 0.001). Increasing C-reactive protein (CRP) levels by tenfold (OR = 5.14; 95% CI, 3.34–8.12; p &lt; 0.001) or suspected chest infection on a radiograph (OR = 5.81; 95% CI, 3.23–10.89; p &lt; 0.001) increased the OR of antibiotic treatment by fivefold. The highest OR for antibiotic prescription was due to increased procalcitonin level by tenfold (OR = 10.13; 95% CI, 4.79–23.4; p &lt; 0.001). Conclusions: Our study provides real-world evidence from a pre-COVID-19 ER setting of diagnostic tools used for RTI evaluation and their impact on antibiotic prescriptions. Rapid influenza-specific PCR results may affect the prescription rate of antibiotics but should be seen as part of a comprehensive diagnostic approach to guide clinical decision-making.

Diagnostic impact of DNA methylation classification in adult and pediatric CNS tumors

Over the past decade, neuropathological diagnosis has undergone significant changes, integrating morphological features with molecular biomarkers. The molecular era has successfully refined neuropathological diagnostic accuracy; however, a substantial number of CNS tumor diagnoses remain challenging, particularly in children. DNA methylation classification has emerged as a powerful machine learning approach for clinical decision-making in CNS tumors. The aim of this study is to share our experience using DNA methylation classification in daily routine practice, illustrated through clinical cases. We employed a classification system to evaluate discrepancies between histo-molecular and DNA methylation diagnoses, with a specific focus on adult versus pediatric CNS tumors. In our study, we observed that 40% of cases fell into Class I, 47% into Class II, and 13% into Class III among the “matched cases” (≥ 0.84). In other words, DNA methylation classification confirmed morphological diagnoses in 63% of adult and 23% of pediatric cases. Refinement of diagnosis was particularly evident in the pediatric population (65% vs. 21% for the adult population, p = 0.006). Additionally, we discussed cases classified with low calibrated scores. In conclusion, our study confirms that DNA methylation classification provides significant added-value for CNS tumors diagnosis, particularly in pediatric cases.

Clinical 7Tesla magnetic resonance imaging: Impact and patient value in neurological disorders.

Magnetic resonance imaging (MRI) is a cornerstone of non-invasive diagnostics and treatment monitoring, particularly for diseases of the central nervous system. Although 1.5- and 3Tesla (T) field strengths remain the clinical standard, the advent of 7T MRI represents a transformative step forward, offering superior spatial resolution, contrast, and sensitivity for visualizing neuroanatomy, metabolism, and function. Recent innovations, including parallel transmission and deep learning-based reconstruction, have resolved many prior technical challenges of 7T MRI, enabling its routine clinical use. This review examines the diagnostic impact, patient value, and practical considerations of 7T MRI, emphasizing its role in facilitating earlier diagnoses and improving care in conditions, such as amyotrophic lateral sclerosis (ALS), epilepsy, multiple sclerosis (MS), dementia, parkinsonism, tumors, and vascular diseases. Based on insights from over 1200 clinical scans with a second-generation 7T system, the review highlights disease-specific biomarkers such as the motor band sign in ALS and the new diagnostic markers in MS, the central vein sign, and paramagnetic rim lesions. The unparalleled ability of 7T MRI to study neurological diseases ex vivo at ultra-high resolution is also explored, offering new opportunities to understand pathophysiology and identify novel treatment targets. Additionally, the review provides a clinical perspective on patient handling and safety considerations, addressing challenges and practicalities associated with clinical 7T MRI. By bridging research and clinical practice, 7T MRI has the potential to redefine neuroimaging and advance the understanding and management of complex neurological disorders.

Reference Ranges and Determinants of Thyroid Function and TSH Receptor Antibodies During Early Pregnancy in Nepal.

Different definitions of thyroid dysfunction during pregnancy may lead to under or overtreatment. The aims of this study were to (1) define population-based pregnancy-specific reference ranges for thyroid dysfunction during early pregnancy in Nepal and assess the impact of antibody positivity, (2) quantify the diagnostic impact of population-based reference ranges compared with current practice and (3) assess the determinants of thyroid function and antibody positivity. A total of 800 healthy pregnant women aged 20-40 years in the Bhaktapur municipality were included. Population-based reference ranges for thyroid hormones levels were defined as 2.5th and 97.5th percentiles using competitive immunoluminometric assay design. Thyroid disease cases and those with recommended treatment indications were calculated using current non-pregnancy new reference ranges. Multivariate regression analyses were performed to identify the determinants of thyroid hormones and antibody levels. Median gestational age was 11 weeks. The reference interval was 0.05-3.69 µLU/mL for thyroid stimulating hormone (TSH) and 8.89-15.28 pg/mL for free tetraiodothyronine (fT4) after excluding thyroid peroxidase antibody-positive women. Compared with the current non-pregnancy reference ranges, the new calculations increased the number of women who required treatment from 5 to 12 (0.9% increase). We identified 19 women (2.4%) who were positive for TSH receptor antibody (TRAb). We could not identify the determinants of TRAb positivity, and TRAb positivity was not associated with TSH or fT4 levels. We found meaningful changes using population-based pregnancy-specific TSH and fT4 reference intervals and encourage further studies in other low- and middle-income settings. Our findings suggest that population screening for TRAb is not clinically meaningful. Clinical Trial Registration: U1111-1183-4093.

Diagnostic Impact of Subcutaneous Edema in Gouty Feet Detected by Dual-Energy Computed Tomography and Ultrasound.

Background: The objective of our study was to evaluate the association and frequency of subcutaneous lymphedema in patients with gout primarily affecting the feet. Methods: In 79 patients with acute gout, ultrasound (US) and dual-energy computed tomography (DECT) were performed to assess the presence of subcutaneous edema and extra- and intra-articular gouty deposits. In addition, the diagnostic utility of two post-processing DECT protocols were evaluated, comprising different minimum attenuation thresholds of 150 HU (DECT 150 protocol) and 120 HU (DECT 120 protocol), with the same maximum attenuation threshold (500 HU) and constant kilovoltage setting of tubes A and B at 80 and 140 kVp. Results: Subcutaneous lymphedema was present in 58.2% of patients, with a significant association with extra-articular monosodium urate (MSU) deposits (p < 0.001). Specifically, 97.8% of patients with lymphedema had extra-articular MSU deposits in DECT or US examination, while no cases of lymphedema were found in patients with exclusively intra-articular deposits. The DECT 120 protocol was significantly more sensitive for detecting peripheral MSU deposits (81%) compared to the DECT 150 protocol (34.2%, p < 0.001). Conclusions: Our findings demonstrate that the presence of lymphedema in patients with gout is frequently associated with extra-articular manifestations of the disease.

Impact of molecular diagnostics and targeted cancer therapy on patient outcomes (MODIFY): a retrospective study of the implementation of precision oncology.

High-throughput genomic analyses are being implemented in clinical practice. MODIFY is a retrospective study of the first introduction of genomic profiling and molecular tumor boards in the country of Luxembourg. The primary objective was to assess whether patients derived a clinical benefit by measuring the percentage of patients who presented a progression-free survival (PFS) on matched therapy (PFS2) 1.3-fold longer than PFS on previous therapy (PFS1). A total of 94 patients were included. In total, 45 patients (53.57% of patients with successful next-generation sequencing [NGS] analysis) were found to have an actionable mutation. Of these, 11 patients received the treatment recommended by the molecular tumor board, another 12 received best-supportive care, and 20 were treated with conventional therapy. PFS2 and PFS1 data were available for eight patients. The PFS2/PFS1 ratio was ≥ -1.3 in 62.5% (n = 5/8; CI [30.38, 86.51]) of patients; three patients showed a partial response, and median overall survival (OS) was 7.3 months. Although the examined population was small, this study further supports evidence indicating that patients with advanced cancer benefit from molecular profiling and targeted therapy.

Laboratory Innovations and their Impact on Precision Medicine and Patient Outcomes: A Systematic Review

Laboratory innovations have revolutionized healthcare by enabling precision medicine, which tailors treatments based on individual patient profiles. This systematic review examines the impact of advanced laboratory technologies, including automation, artificial intelligence, and molecular diagnostics, on precision medicine and patient outcomes. A comprehensive analysis of recent studies highlights the pivotal role of these innovations in enhancing diagnostic accuracy, streamlining workflows, and improving therapeutic interventions. The findings demonstrate significant contributions to reducing medical errors, accelerating treatment delivery, and optimizing resource utilization in clinical settings. Challenges such as integration costs and training requirements are also discussed, offering insights for future research and implementation strategies. This review underscores the transformative potential of laboratory advancements in shaping personalized healthcare and achieving superior patient outcomes.

Hepatic artery peak systolic velocity compared to non-Doppler ultrasound observations for predicting acute cholecystitis: diagnostic performance and impact on a risk categorization approach.

Compare HAv to non-Doppler ultrasound observations for diagnosing acute cholecystitis in a large consecutive cohort of emergency department (ED) patients and establish a method to combine HAv assessment with non-Doppler observations for diagnosing acute cholecystitis. Consecutive ED patients at one institution undergoing gallbladder (GB) ultrasound (US) for acute cholecystitis between 1/1/2020 and 8/31/2022 had assessments of GB diameter, GB wall thickness, GB contents, pericholecystic irregular collection, and hepatic artery peak systolic velocity (HAv). The non-Doppler observations were scored and summed. Non-Doppler risk categorization was based on rate of acute cholecystitis associated with summed scores. The impact of HAv stratification on the rate of acute cholecystitis in the non-Doppler risk categories was evaluated, with regrouping when subgroups had changes in the acute cholecystitis rate; the regrouping established the HAv-adjusted risk model. Receiver-operator curves for acute cholecystitis diagnosis for individual parameters, the non-Doppler risk categorization, and the HAv-adjusted risk model were compared using area-under-curve (AUC) calculations. Of the 885 patients in the study cohort, 117 (13.2%) had acute cholecystitis. The AUC for diagnosing acute cholecystitis using GB distention (83.8%, p < 0.001), GB wall thickness (79.1%, p < 0.001), and GB contents (75.0%, p 0.02) were higher than HAv (66.3%). HAv assessment adjusted risk for 195 patients. The non-Doppler risk categorization and the HAv-adjusted risk model had the same sensitivity (84.6%) and specificity (85.2%) for diagnosing acute cholecystitis, but the HAv-adjusted risk model showed higher AUC (91.3%, p 0.03) due to increased ability to exclude acute cholecystitis. The diagnostic performance of HAv for acute cholecystitis was lower than other assessments. A categorization scheme based on summed points assigned to each non-Doppler observation was improved with HAv assessment. This risk categorization approach using formulaic integration of non-Doppler and Doppler assessments on ED patients allows radiologists to convey one of five levels of disease probability based solely on sonographic features ranging from effectively excluding acute cholecystitis to substantially elevating the chance the patient has the condition.

Impact of shortening time on diagnosis of 18F-florbetaben PET

Background18F-Florbetaben amyloid positron emission tomography (PET) scan is crucial for diagnosing Alzheimer’s disease, typically involving a 20 min acquisition. However, maintaining such prolonged scans can be challenging in some cases. This study explores the diagnostic impact and feasibility of reducing scan durations by comparing quantitative measures between shortened and standard scans. Additionally, we identified the optimal Centiloid threshold to distinguish between positive and negative amyloid results.ResultsWe analyzed 307 PET scans from our memory clinic, each followed up for a minimum of two years. The scans, conducted 90 to 110 min after approximately 300 MBq of 18F-Florbetaben injection, were categorized into four sets of 5 min durations: 5, 10, 15, and 20 min. Nuclear medicine physicians validated and rated each scan as either amyloid-positive or negative. For quantitative assessments, we employed the standardized uptake value ratio (SUVR) and Centiloid scales, comparing total SUVR and Centiloid values across five subregions (global, frontal, posterior cingulate-precuneus, lateral temporal, and parietal) using Bland–Altman analysis. Receiver operator characteristic (ROC) curves were utilized to develop optimal Centiloid thresholds. Comparing the images at 5, 10, 15, and 20 min images, SUVR and Centiloid values gradually increased with prolonged scan times. The mean SUVR difference between 5 and 20 min was 0.03 for the amyloid-positive and 0.01 for the amyloid-negative groups; Centiloid differences were 4.60 and 2.38, respectively. Additionally, no significant variation was observed in total SUVR and Centiloid values among the durations across all subregions in positive and negative groups (all p > 0.1). ROC analysis indicated that a Centiloid threshold of 21.86 at 5 min provided optimal agreement with visual assessments (AUC = 0.985, sensitivity = 0.950, specificity = 0.972), especially using the global area.ConclusionsThis study demonstrated that 5 min image scans with an optimal threshold of CL = 21.86 exhibited minimal bias in SUVR and Centiloid values compared to longer scans (10, 15, and 20 min). Our findings suggest that shorter scan times are a viable and effective option for brain amyloid PET imaging in clinical settings.

LI-RADS Nonradiation Treatment Response Algorithm Version 2024: Diagnostic Performance and Impact of Ancillary Features.

Background: LI-RADS Treatment Response Algorithm (TRA) version 2024 (v2024) introduced separate algorithms for detecting hepatocellular carcinoma (HCC) viability after radiation and nonradiation locoregional therapies (LRT). The nonradiation algorithm incorporated MRI-based ancillary features to optionally upgrade lesions from LR-TR Equivocal to LR-TR Viable. Objective: To compare the diagnostic performance of LI-RADS Nonradiation TRA v2024 with LI-RADS TRA version 2017 (v2017) and modified RECIST (mRECIST) for evaluating HCC response to LRT on MRI, with attention to the impact of ancillary features. Methods: This retrospective study included 231 patients (198 male, 33 female; median age, 56 years) who underwent LRT for HCC followed by liver resection or transplant between January 2017 and December 2022. Two radiologists (R1, R2) independently evaluated treated lesions (n=306) using LI-RADS Nonradiation TRA v2024, LI-RADS TRA v2017, and mRECIST. Lesions were classified as showing pathologic viability (n=249) or complete pathologic necrosis (n=57) based on curative surgery pathology. Diagnostic performance for pathologic viability was compared using Bonferroni-adjusted McNemar tests, classifying LR-TR Equivocal assessments as test negative. Results: Sensitivity, specificity, and accuracy for LI-RADS Nonradiation TRA v2024 with ancillary features were 85.5%, 75.4%, and 83.7% (R1), and 87.2%, 63.2%, and 82.7% (R2); for LI-RADS Nonradiation TRA v2024 without ancillary features were 81.1%, 78.9%, and 80.7% (R1), and 80.3%, 78.9%, and 80.1% (R2); for LI-RADS TRA v2017 were 79.9%, 82.5%, and 80.4% (R1), and 79.1%, 79.0%, and 79.1% (R2); and for mRECIST, were 83.9%, 54.4%, and 78.4% (R1), and 78.2%, 40.4%, and 78.4% (R2). LI-RADS Nonradiation TRA v2024 with ancillary features showed higher sensitivity and accuracy than LI-RADS Nonradiation v2024 without ancillary features (both readers); higher sensitivity than LI-RADS TRA v2017 (both readers); higher specificity than mRECIST (both readers); and higher accuracy than LI-RADS TRA v2017 (R2) (p<.008); remaining comparisons between LI-RADS Nonradiation TRA v2024 with ancillary features and other systems were not significant (p>.008). Conclusion: LI-RADS Nonradiation TRA v2024 showed good diagnostic performance in detecting pathologic viability. Ancillary features yielded improved sensitivity and accuracy without significant change in specificity. Clinical Impact: Use of LI-RADS Nonradiation TRA v2024 with ancillary features is recommended for guiding prognostic assessments and treatment decisions after LRT.

Abstract 4137449: Diagnostic Yield and Testing Characteristics of an Invasive Coronary Function Testing Program

Background: Angina, ischemia, or myocardial infarction in the absence of obstructive coronary artery disease (ANOCA, INOCA, or MINOCA) is common and underdiagnosed. Invasive coronary function testing (CFT) for microvascular disease through coronary thermodilution and for coronary vasospasm through coronary reactivity testing can provide definitive diagnoses and improve patient quality of life. Here, we describe a single site experience launching a CFT program and present the diagnostic yield and test characteristics of the first 66 patients. Methods: The first 66 patients who underwent invasive CFT at Mass General Hospital after the launch of the program in 2022 were included. Invasive CFT data and clinical characteristics before and after were entered into a registry. We used descriptive statistics to summarize patient characteristics, diagnostic yield and change in management with invasive CFT. We describe the dose-response and safety of incremental doses of acetylcholine. Results: Among 66 patients (mean age 61.73±11.02 years, 56% female), 17 patients underwent testing at the time of an index angiogram and 49 were scheduled after knowledge of coronary anatomy. Reasons for invasive coronary function testing were post-revascularization angina (n=30, 45.5%), ANOCA (n=21, 31.8%), INOCA (n=9, 13.6%), MINOCA (n=4, 6.1%), and heart transplant patients (n=2, 3%). 24 (36.3%) patients underwent coronary thermodilution only, 6 (9.1%) coronary reactivity testing only , and 36 (54.5%) both. CFT resulted in a definitive diagnosis in 45 (68.1%) of participants – 37.9% with coronary vasospasm only, 13.6% with microvascular dysfunction only, and 16.7% with both. There were 21 (31.8%) patients who remained negative after invasive CFT. Invasive CFT led to a change in management in 46 (70%) patients. For example, nitrate, calcium channel blocker and beta blocker prescriptions were modified in 47%, 50%, and 52.3% of patients, respectively. Among 42 patients who underwent coronary reactivity testing by provocation with intracoronary acetylcholine doses of 20, 100, and 200 mcg, there was a dose-response to angina (18.5%, 70.2%, and 95.2%), ischemic ECG changes (11.1%, 75.7%, and 95.2%), and vessel spasm of greater than 90% (3.7%, 27%, and 57.1%). There was only one safety event(PTCA to re-establish flow after spasm). Conclusions: We demonstrate the safe implementation of an invasive coronary function testing program with very high diagnostic yield and impact on management.

Abstract 4127891: Value of Left Ventricular and Left Atrial Strains in Loeffler Endocarditis and Hypereosinophilic Syndrome

Background: Hypereosinophilic syndrome (HES) is a rare disease that causes organ damage and thrombosis due to sustained eosinophilia of the blood or tissues. Loeffler endocarditis (LE) is defined as cardiac involvement in the setting of HES. There are limited data on the diagnostic and prognostic impact of strain imaging on LE. Methods: A single-center retrospective cohort study was performed. Patients with eosinophilia between January 2000 and January 2023 were identified. We included patients who met the current diagnostic criteria for HES and underwent echocardiography prior to treatment. LE was defined as the presence of eosinophils in the myocardium by an endomyocardial biopsy, endocardial thickening, or left ventricular thrombus due to HES. We evaluated the composite events defined as CV death and stroke at diagnosis and during follow-up. Results: Of 1,664 patients with eosinophilia, 34 patients with HES were included (10 with LE and 24 without LE). In the entire cohort, the mean age was 57 ± 16 years and 41% were male. The median follow-up duration was 85 months (25th -75th percentile: 41-145 months). The composite events occurred in 6 patients. Left ventricular ejection fraction (LVEF) was similar in both groups (60% vs. 61%, p = 0.691). Patients with LE had significantly lower left ventricular global longitudinal strain (LV-GLS) (-9.7% vs. -15.5%, p = 0.001), left atrial (LA) reservoir strain (21.0% vs. 32.1%, p = 0.021) and LA conduit strain (-9.7% vs. -19.2%, p &lt;0.001), compared to patients without LE. There were no significant differences in LA booster strain (-11.3% vs. -12.8%, p = 0.606) and right ventricular free wall strain (-17.5% vs. -23.4%, p = 0.083). All LE patients and half of non-LE patients had LV-GLS worse than -16 %. There was a significant difference in the compsoite events for patients with LV-GLS worse than -16% (28.6% vs. 0.0%, p = 0.049). Conclusions: LE was associated with significantly worse LV-GLS and left atrial strain compared to patients without LE. Worse LV-GLS was associated with a higher frequency of the composite events.

Optical Genome Mapping As Standard-of-Care in Acute Leukemia: Diagnostic and Clinical Impacts 10 Months Post-Implementation

Optical Genome Mapping As Standard-of-Care in Acute Leukemia: Diagnostic and Clinical Impacts 10 Months Post-Implementation