Investigative Radiology最新文献

{"title":"Implementation of an AI Algorithm in Clinical Practice to Reduce Missed Incidental Pulmonary Embolisms on Chest CT and Its Impact on Short-Term Survival.","authors":"Vera Inka Josephin Graeve, Simin Laures, Andres Spirig, Hasan Zaytoun, Claudia Gregoriano, Philipp Schuetz, Felice Burn, Sebastian Schindera, Tician Schnitzler","doi":"10.1097/RLI.0000000000001122","DOIUrl":"10.1097/RLI.0000000000001122","url":null,"abstract":"<p><strong>Objectives: </strong>A substantial number of incidental pulmonary embolisms (iPEs) in computed tomography scans are missed by radiologists in their daily routine. This study analyzes the radiological reports of iPE cases before and after implementation of an artificial intelligence (AI) algorithm for iPE detection. Furthermore, we investigate the anatomic distribution patterns within missed iPE cases and mortality within a 90-day follow-up in patients before and after AI use.</p><p><strong>Materials and methods: </strong>This institutional review board-approved observational single-center study included 5298 chest computed tomography scans performed for reasons other than suspected pulmonary embolism (PE). We compared 2 cohorts: cohort 1, consisting of 1964 patients whose original radiology reports were generated before the implementation of an AI algorithm, and cohort 2, consisting of 3334 patients whose scans were analyzed after the implementation of an Food and Drug Administration-approved and CE-certified AI algorithm for iPE detection (Aidoc Medical, Tel Aviv, Israel). For both cohorts, any discrepancies between the original radiology reports and the AI results were reviewed by 2 thoracic imaging subspecialized radiologists. In the original radiology report and in case of discrepancies with the AI algorithm, the expert review served as reference standard. Sensitivity, specificity, prevalence, negative predictive value (NPV), and positive predictive value (PPV) were calculated. The rates of missed iPEs in both cohorts were compared statistically using STATA (Version 17.1). Kaplan-Meier curves and Cox proportional hazards models were used for survival analysis.</p><p><strong>Results: </strong>In cohort 1 (mean age 70.6 years, 48% female [n = 944], 52% male [n = 1020]), the prevalence of confirmed iPE was 2.2% (n = 42), and the AI detected 61 suspicious iPEs, resulting in a sensitivity of 95%, a specificity of 99%, a PPV of 69%, and an NPV of 99%. Radiologists missed 50% of iPE cases in cohort 1. In cohort 2 (mean age 69 years, 47% female [n = 1567], 53% male [n = 1767]), the prevalence of confirmed iPEs was 1.7% (56/3334), with AI detecting 59 suspicious cases (sensitivity 90%, specificity 99%, PPV 95%, NPV 99%). The rate of missed iPEs by radiologists dropped to 7.1% after AI implementation, showing a significant improvement ( P < 0.001). Most overlooked iPEs (61%) were in the right lower lobe. The survival analysis showed no significantly decreased 90-day mortality rate, with a hazards ratio of 0.95 (95% confidence interval, 0.45-1.96; P = 0.88).</p><p><strong>Conclusions: </strong>The implementation of an AI algorithm significantly reduced the rate of missed iPEs from 50% to 7.1%, thereby enhancing diagnostic accuracy. Despite this improvement, the 90-day mortality rate remained unchanged. These findings highlight the AI tool's potential to assist radiologists in accurately identifying iPEs, although its implementation does not s","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"260-266"},"PeriodicalIF":7.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing Catheter Verification: An Understandable AI Model for Efficient Assessment of Central Venous Catheter Placement in Chest Radiography.","authors":"Jonas Stroeder, Malte Multusch, Lennart Berkel, Lasse Hansen, Axel Saalbach, Heinrich Schulz, Mattias P Heinrich, Yannic Elser, Jörg Barkhausen, Malte Maria Sieren","doi":"10.1097/RLI.0000000000001126","DOIUrl":"10.1097/RLI.0000000000001126","url":null,"abstract":"<p><strong>Purpose: </strong>Accurate detection of central venous catheter (CVC) misplacement is crucial for patient safety and effective treatment. Existing artificial intelligence (AI) often grapple with the limitations of label inaccuracies and output interpretations that lack clinician-friendly comprehensibility. This study aims to introduce an approach that employs segmentation of support material and anatomy to enhance the precision and comprehensibility of CVC misplacement detection.</p><p><strong>Materials and methods: </strong>The study utilized 2 datasets: the publicly accessible RANZCR CLiP dataset and a bespoke in-house dataset of 1006 annotated supine chest x-rays. Three deep learning models were trained: a classification network, a segmentation network, and a combination of both. These models were evaluated using receiver operating characteristic analysis, area under the curve, DICE similarity coefficient, and Hausdorff distance.</p><p><strong>Results: </strong>The combined model demonstrated superior performance with an area under the curve of 0.99 for correctly positioned CVCs and 0.95 for misplacements. The model maintained high efficacy even with reduced training data from the local dataset. Sensitivity and specificity rates were high, and the model effectively managed the segmentation and classification tasks, even in images with multiple CVCs and other support materials.</p><p><strong>Conclusions: </strong>This study illustrates the potential of AI-based models in accurately and reliably determining CVC placement in chest x-rays. The proposed method shows high accuracy and offers improved interpretability, important for clinical decision-making. The findings also highlight the importance of dataset quality and diversity in training AI models for medical image analysis.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"267-274"},"PeriodicalIF":7.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142894293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimal Spectral Performance on Pediatric Photon-Counting CT: Investigating Phantom-Based Size-Dependent kV Selection for Spectral Body Imaging.","authors":"Wei Zhou, Afrouz Ataei, Donglai Huo, Liqiang Ren, Lorna P Browne, Xin Zhou, Jason P Weinman","doi":"10.1097/RLI.0000000000001119","DOIUrl":"10.1097/RLI.0000000000001119","url":null,"abstract":"<p><strong>Purpose: </strong>The comprehensive evaluation of kV selection on photon-counting computed tomography (PCCT) has yet to be performed. The aim of the study is to evaluate and determine the optimal kV options for variable pediatric body sizes on the PCCT unit.</p><p><strong>Materials and methods: </strong>In this study, 4 phantoms of variable sizes were utilized to represent abdomens of newborn, 5-year-old, 10-year-old, and adult-sized pediatric patients. One solid water and 4 solid iodine inserts with known concentrations (2, 5, 10, and 15 mg I/mL) were inserted into phantoms. Each phantom setting was scanned on a PCCT system (Siemens Alpha) with 4 kV options (70 and 90 kV under Quantum Mode, 120 and 140 kV under QuantumPlus Mode) and clinical dual-source (3.0 pitch) protocol. For each phantom setting, radiation dose (CTDI vol ) was determined by clinical dose settings and matched for all kV acquisitions. Sixty percent clinical dose images were also acquired. Reconstruction was matched across all acquisitions using Qr40 kernel and QIR level 3. Virtual monoenergetic images (VMIs) between 40 and 80 keV with 10 keV interval were generated on the scanner. Low-energy and high-energy images were reconstructed from each scan and subsequently used to generate an iodine map (IM) using an image-based 2-material decomposition method. Image noise of VMIs from each kV acquisition was calculated and compared between kV options. Absolute percent error (APE) of iodine CT number accuracy in VMIs was calculated and compared. Root mean square error (RMSE) and bias of iodine quantification from IMs were compared across kV options.</p><p><strong>Results: </strong>At the newborn size and 50 keV VMI, noise is lower at low kV acquisitions (70 kV: 10.5 HU, 90 kV: 10.4 HU), compared with high kV acquisitions (120 kV: 13.8 HU, 140 kV: 13.9 HU). At the newborn size and 70 keV VMI, the image noise from different kV options is comparable (9.4 HU for 70 kV, 8.9 HU for 90 kV, 9.7 HU for 120 kV, 10.2 HU for 140 kV). For APE of VMI, high kV (120 or 140 kV) performed overall better than low kV (70 or 90 kV). At the 5-year-old size, APE of 90 kV (median: 3.6%) is significantly higher ( P < 0.001, Kruskal-Wallis rank sum test with Bonferroni correction) than 140 kV (median: 1.6%). At adult size, APE of 70 kV (median: 18.0%) is significantly higher ( P < 0.0001, Kruskal-Wallis rank sum test with Bonferroni correction) than 120 kV (median: 1.4%) or 140 kV (median: 0.8%). The high kV also demonstrated lower RMSE and bias than the low kV across all controlled conditions. At 10-year-old size, RMSE and bias of 120 kV are 1.4 and 0.2 mg I/mL, whereas those from 70 kV are 1.9 and 0.8 mg I/mL.</p><p><strong>Conclusions: </strong>The high kV options (120 or 140 kV) on the PCCT unit demonstrated overall better performance than the low kV options (70 or 90 kV), in terms of image quality of VMIs and IMs. Our results recommend the use of high kV for general body imaging on the PCCT.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"245-252"},"PeriodicalIF":7.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142004230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Comprehensive and Repeatable Contrast-Enhanced Ultrasound Quantification Approach for Clinical Evaluations of Tumor Blood Flow.","authors":"Connor Krolak, Angela Wei, Marissa Shumaker, Manjiri Dighe, Michalakis Averkiou","doi":"10.1097/RLI.0000000000001127","DOIUrl":"10.1097/RLI.0000000000001127","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Objective: &lt;/strong&gt;The aim of this study is to define a comprehensive and repeatable contrast-enhanced ultrasound (CEUS) imaging protocol and analysis method to quantitatively assess lesional blood flow. Easily repeatable CEUS evaluations are essential for longitudinal treatment monitoring. The quantification method described here aims to provide a structure for future clinical studies.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Materials and methods: &lt;/strong&gt;This retrospective analysis study included liver CEUS studies in 80 patients, 40 of which contained lesions (primarily hepatocellular carcinoma, n = 28). Each patient was given at least 2 injections of a microbubble contrast agent, and 60-second continuous loops were acquired for each injection to enable evaluation of repeatability. For each bolus injection, 1.2 mL of contrast was delivered, whereas continuous, stationary scanning was performed. Automated respiratory gating and motion compensation algorithms dealt with breathing motion. Similar in size regions of interest were drawn around the lesion and liver parenchyma, and time-intensity curves (TICs) with linearized image data were generated. Four bolus transit parameters, rise time ( RT ), mean transit time ( MTT ), peak intensity ( PI ), and area under the curve ( AUC ), were extracted either directly from the actual TIC data or from a lognormal distribution curve fitted to the TIC. Interinjection repeatability for each parameter was evaluated with coefficient of variation. A 95% confidence interval was calculated for all fitted lognormal distribution curve coefficient of determination ( R2 ) values, which serves as a data quality metric. One-sample t tests were performed between values obtained from injection pairs and between the fitted lognormal distribution curve and direct extraction from the TIC calculation methods to establish there were no significant differences between injections and measurement precision, respectively.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;Average interinjection coefficient of variation with both the fitted curve and direct calculation of RT and MTT was less than 21%, whereas PI and AUC were less than 40% for lesion and parenchyma regions of interest. The 95% confidence interval for the R2 value of all fitted lognormal curves was [0.95, 0.96]. The 1-sample t test for interinjection value difference showed no significant differences, indicating there was no relationship between the order of the repeated bolus injections and the resulting parameters. The 1-sample t test between the values from the fitted lognormal distribution curve and the direct extraction from the TIC calculation found no statistically significant differences (α = 0.05) for all perfusion-related parameters except lesion and parenchyma PI and lesion MTT .&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;The scanning protocol and analysis method outlined and validated in this study provide easily repeatable quantitative evaluations of lesional blood flow with bolus transit par","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"281-290"},"PeriodicalIF":7.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11888899/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142465523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Epineural Scarring Visualization and Noninvasive Quantification of a Severe Posttraumatic Complication: An Experimental Magnetic Resonance Neurography Study.","authors":"Merle Brunnée, Martin Aman, Maximilian Mayrhofer-Schmid, Manuel Fischer, Simeon C Daeschler, Tess Klemm, Ulrich Kneser, Kianush Karimian-Jazi, Michael O Breckwoldt, Leila Harhaus, Sabine Heiland, Martin Bendszus, Arne H Boecker, Daniel Schwarz","doi":"10.1097/RLI.0000000000001132","DOIUrl":"10.1097/RLI.0000000000001132","url":null,"abstract":"<p><strong>Aim: </strong>Peripheral nerve scarring is a severe yet common complication following nerve injury or surgery that can lead to impaired nerve function, including chronic pain and sensory or motor deficits. In this study, we aimed to establish high-resolution magnetic resonance neurography (MRN) to accurately visualize and monitor de novo-formed epineural fibrotic adhesions (EFAs) of the sciatic nerve in a rat nerve injury model.</p><p><strong>Methods: </strong>Employing an established model to induce overshooting EFA, the study included 3 experimental groups of animals (n = 6 each): a positive control group (PC), an intervention group (IG), and a sham group. All groups underwent surgical nerve exposure: both PC and IG received an application of 10 μL 2.5% glutaraldehyde to induce EFA, but only IG received an additional preventive wrapping of the nerve with a collagen-containing matrix. Magnetic resonance imaging was performed 6, 8, and 12 weeks postoperatively using a standardized protocol including T2w and T1w without and with contrast media. Motor function and nerve regeneration was assessed using the visual static sciatic index. Histological specimens were obtained 12 weeks postoperatively and correlated with imaging.</p><p><strong>Results: </strong>On high-resolution MRN, prominently contrast-enhancing epineural sleeves were present in vivo, which corresponded to histologically confirmed EFA (ratio of EFA to nerve area MRN 1.512 ± 0.106 vs histological ratio 1.459 ± 0.208, nonsignificant). As expected, average EFA in IG (0.310 ± 0.118 mm 2 ) was smaller than in PC (0.909 ± 0.212 mm 2 , P < 0.01). Also, the average EFA in sham (0.386 ± 0.030 mm 2 ) was less pronounced than in PC ( P < 0.01). There was no significant difference in the average EFA between IG und sham. The EFA correlated with the functional outcome, which was measured by visual static sciatic index (correlation coefficient -0.59, P < 0.05).</p><p><strong>Conclusions: </strong>The results of the present study for the first time confirm the clinical observation that epineural thickening on contrast-enhanced T1w imaging following manipulation to a nerve indeed corresponds to overshooting epineural scarring, which may be linked to impaired nerve function. This can be followed noninvasively in vivo over time providing an important basis for clinical decision-making in cases where further invasive therapies may be necessary.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"275-280"},"PeriodicalIF":7.0,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fixed Versus Patient-Specific Trigger Delay in High-Pitch Computed Tomography Angiography of the Aorta Prior to Transcatheter Aortic Valve Implantation: Assessment of Image Quality and Homogeneity of Vessel Enhancement.","authors":"Sidre Sahin-Uzuner, Foroud Aghapour Zangeneh, Goncalo De Almeida, Oezlem Krzystek, Maria Paslak, Jakob Heimer, Ralf Gutjahr, Thomas Sartoretti, Tilo Niemann, André Euler","doi":"10.1097/RLI.0000000000001176","DOIUrl":"https://doi.org/10.1097/RLI.0000000000001176","url":null,"abstract":"<p><strong>Objective: </strong>The aim of the study is to compare the image quality and homogeneity of vessel enhancement in high-pitch CT-angiography of the aorta (CTA) prior to transcatheter aortic valve implantation between bolus tracking with a fixed trigger delay and bolus tracking with a patient-specific trigger delay.</p><p><strong>Materials and methods: </strong>In this retrospective study, consecutive patients who received a CTA of the aorta prior to transcatheter aortic valve implantation between January 2023 and June 2024 were included. Patients were imaged using either bolus tracking and a fixed trigger delay (Group A; 15 seconds) or bolus tracking and a patient-specific trigger delay (Group B; FAST Bolus; Siemens Healthineers AG). The same contrast injection and scan protocol were used in both groups. Vessel enhancement was measured at multiple craniocaudal locations. Subjective image quality was assessed by 2 readers using 5-point Likert scales. Likert scores were analyzed using Wilcoxon rank-sum tests. Enhancement was assessed with a mixed-effects model.</p><p><strong>Results: </strong>Sixty-five patients (28 females) were assessed in each group. Patient demographics (both 74 ± 12 years; P = 0.58, body mass index: 26.0 vs 26.2 kg/m2; P = 0.79) and radiation dose (CTDIvol: 3.4 vs 3.5 mGy; P = 0.55) did not differ significantly between the two groups. Mean CT attenuation was 489 HU versus 469 HU in the ascending aorta and 428 HU versus 464 HU in the common femoral artery for fixed and patient-specific delays, respectively. Enhancement in the femoral arteries was significantly lower in the fixed delay group (P < 0.05), while there was no significant difference at other vessel locations. Diagnostic image quality and enhancement at the femoral artery were rated significantly better for the patient-specific trigger delay by one reader (both P < 0.05).</p><p><strong>Conclusions: </strong>Bolus tracking with a patient-specific trigger delay improved the craniocaudal homogeneity of vessel enhancement and subjective image quality at the distal access site as compared to bolus tracking with a fixed trigger delay in high-pitch CTA prior to TAVI.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emerging Trends and Innovations in Radiologic Diagnosis of Thoracic Diseases.","authors":"Jiyoung Song, Eui Jin Hwang, Soon Ho Yoon, Chang Min Park, Jin Mo Goo","doi":"10.1097/RLI.0000000000001179","DOIUrl":"https://doi.org/10.1097/RLI.0000000000001179","url":null,"abstract":"<p><strong>Abstract: </strong>Over the past decade, Investigative Radiology has published numerous studies that have fundamentally advanced the field of thoracic imaging. This review summarizes key developments in imaging modalities, computational tools, and clinical applications, highlighting major breakthroughs in thoracic diseases-lung cancer, pulmonary nodules, interstitial lung disease (ILD), chronic obstructive pulmonary disease (COPD), COVID-19 pneumonia, and pulmonary embolism-and outlining future directions.Artificial intelligence (AI)-driven computer-aided detection systems and radiomic analyses have notably improved the detection and classification of pulmonary nodules, while photon-counting detector CT (PCD-CT) and low-field MRI offer enhanced resolution or radiation-free strategies. For lung cancer, CT texture analysis and perfusion imaging refine prognostication and therapy planning. ILD assessment benefits from automated diagnostic tools and innovative imaging techniques, such as PCD-CT and functional MRI, which reduce the need for invasive diagnostic procedures while improving accuracy. In COPD, dual-energy CT-based ventilation/perfusion assessment and dark-field radiography enable earlier detection and staging of emphysema, complemented by deep learning approaches for improved quantification. COVID-19 research has underscored the clinical utility of chest CT, radiographs, and AI-based algorithms for rapid triage, disease severity evaluation, and follow-up. Furthermore, tuberculosis remains a significant global health concern, highlighting the importance of AI-assisted chest radiography for early detection and management. Meanwhile, advances in CT pulmonary angiography, including dual-energy reconstructions, allow more sensitive detection of pulmonary emboli.Collectively, these innovations demonstrate the power of merging novel imaging technologies, quantitative functional analysis, and AI-driven tools to transform thoracic disease management. Ongoing progress promises more precise and personalized diagnostic and therapeutic strategies for diverse thoracic diseases.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Developing Magnetic Resonance Imaging Biomarkers of Neuroinflammation, Cognitive Impairment, and Survival Outcomes for Radiotherapy-Induced Brain Injury in a Preclinical Mouse Model.","authors":"Maya Teitz, Esteban Velarde, Xiaoju Yang, Shana Lee, Kristen Lecksell, Chantelle Terrillion, Adnan Bibic, Ethel J Ngen","doi":"10.1097/RLI.0000000000001173","DOIUrl":"10.1097/RLI.0000000000001173","url":null,"abstract":"<p><strong>Objective: </strong>Radiotherapy-induced brain injury (RIBI) is a chronic side effect that affects up to 90% of brain tumor survivors treated with radiotherapy. Here, we used multiparametric magnetic resonance imaging (MRI) to identify noninvasive and clinically translatable biomarkers of RIBI.</p><p><strong>Method: </strong>8-week-old female, immune competent BALB/c mice were stereotactically irradiated with a single dose of 80 Gy, at a dose rate of 1.7 Gy/minute. The irradiated mice were then monitored longitudinally with MRI, behavioral tests of learning and memory, and immunohistochemistry, in comparison to nonirradiated mice.</p><p><strong>Results: </strong>Three types of MRI biomarkers of RIBI were identified. A contrast-enhanced T1-weighted MRI biomarker was identified as being best suited to detect the onset of injury, by detecting changes in the blood-brain barrier (BBB) permeability. Maximum BBB permeability (18.95 ± 1.75) was detected with contrast-enhanced T1-weighted MRI at 1-month postirradiation in irradiated mice (P < 0.0001, n = 3). Interestingly, maximum neuroinflammation (24.14 ± 6.72) was also detected using IBA1 and CD68 immunohistochemistry at 1-month postirradiation in irradiated mice (P = 0.0041, n = 3). This simultaneous maximum BBB permeability and neuroinflammation detection also coincided with the detection of the onset of transient cognitive impairment, detected using the fear-conditioning behavioral test at 1-month postirradiation in irradiated mice compared to nonirradiated mice (P = 0.0017, n = 10). A T2-weighted MRI hyperintensity biomarker was also identified, and determined to be best suited to detect intermediate injury. Maximum T2-weighted MRI hyperintensity (3.97 ± 2.07) was detected at 2-month postirradiation in the irradiated mice compared to nonirradiated mice (P = 0.0368, n = 3). This T2-weighted MRI hyperintensity also correlated with maximum astrogliosis (9.92 ± 4.21), which was also detected at 2-month postirradiation using GFAP immunohistochemistry in the irradiated mice compared to nonirradiated mice (P = 0.0215, n = 3). Finally, T2-weighted and T2*-weighted MRI hypointensity biomarkers were identified as being best suited to detect late injury, from 4-month postirradiation. These biomarkers correlated with increased iron deposition from late vascular damage, which was validated with Perls' Prussian blue histology (P < 0.05, n = 3). These hypointense MRI biomarkers of late injury also preceded significant weight loss, severe cognitive impairment, and decreased survival in the irradiated mice compared to the nonirradiated mice.</p><p><strong>Conclusions: </strong>Here, we identified 3 types of translational MRI biomarkers of RIBI that could enable the noninvasive longitudinal evaluation of potential RIBI prophylactic and therapeutic agents. These translational MRI biomarkers could also play a pivotal role in the management of RIBI in brain tumor survivors.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":""},"PeriodicalIF":8.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12353168/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143648471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance of an Intravascular Tantalum Oxide-Based Nanoparticle Computed Tomography Contrast Agent in Preclinical Hepatic Tumor Detection.","authors":"Maurice M Heimer, Yuxin Sun, Peter J Bonitatibus, Johanna Luitjens, Cheng W Hong, Nikki Okwelogu, Sina Houshmand, Theresia Aschauer, Clemens C Cyran, Michael Ingrisch, Brian C Bales, Dan E Meyer, Benjamin M Yeh","doi":"10.1097/RLI.0000000000001175","DOIUrl":"https://doi.org/10.1097/RLI.0000000000001175","url":null,"abstract":"<p><strong>Background: </strong>Noniodinated intravenous contrast agents have shown significant potential to improve computed tomography (CT) imaging; however, in vivo evidence for impact on lesion detection remains scarce.</p><p><strong>Purpose: </strong>The aim of the study was to compare a novel intravenous carboxybetaine zwitterionic-coated tantalum oxide (TaCZ) nanoparticle contrast agent to clinical iodinated contrast agent for the detection of liver tumors in a rabbit tumor model at CT.</p><p><strong>Methods: </strong>Following hepatic implantation of VX2 tumors, n = 10 rabbits were repeatedly scanned on a clinical CT system before and at 40, 105, and 180 seconds after intravenous contrast injection of 540 mg element (Ta or I) per kilogram of body weight using TaCZ or iopamidol. After contrast elimination, imaging was repeated with the other contrast agent in each rabbit. Findings were compared to gross pathology. Three readers independently reviewed n = 114 randomized image series for hepatic tumors and rated conspicuity on a 5-point scale (1 = barely visible to 4 = obvious; 0 = not detected). Regions of interest drawn by readers were used to calculate contrast to noise ratio. Metrics were compared between contrast agents for different tumor size categories (3-6 mm, >6-11 mm, >11-14 mm, >14 mm) and for venous scan delays between contrast agents.</p><p><strong>Results: </strong>TaCZ provided higher hepatic contrast enhancement resulting in superior Contrast-to-noise ratio (CNR) of hepatic tumors at all examined venous contrast delays (5.7-6.9 vs 3.9-4.5; all P < 0.001) compared to iopamidol. This translated into improved overall sensitivity (all P < 0.001) and detection of small hepatic tumors ≤11 mm (all P≤0.002). In addition, compared to iopamidol, TaCZ showed higher tumor conspicuity in all subgroups. Larger lesion size and early contrast delay were associated with improved lesion detection for both contrast agents.</p><p><strong>Conclusions: </strong>Experimental TaCZ nanoparticles showed higher hepatic contrast enhancement and improved the detection and conspicuity of hepatic tumors at all sizes and scan delays compared to iopamidol, with sustained intense contrast enhancement in delayed venous phase up to at least 180 seconds.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143657182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Discovery of Gadopiclenol: An Example of Rational Drug Design?","authors":"Marc Port","doi":"10.1097/RLI.0000000000001169","DOIUrl":"https://doi.org/10.1097/RLI.0000000000001169","url":null,"abstract":"<p><strong>Abstract: </strong>Gadopiclenol was initially developed as a high-relaxivity, nonspecific magnetic resonance imaging contrast agent to enhance image quality and thereby improve diagnostics. This design required a highly demanding Drug Target Profile, addressing not only relaxivity but also factors such as physicochemical properties of the injectable solution (viscosity, osmolality, heat sterilization compatibility), pharmacokinetics and toxicity, particularly related to the stability of the complex. These considerations led to a multiparametric molecular design based on a gadolinium complex characterized by the following features: (1) a macrocyclic, nonionic structure based on the PCTA framework with 2 water molecules in the inner sphere; (2) the introduction of steric constraints around the gadolinium to enhance stability and reduce relaxivity quenching by endogenous ions; (3) slowed rotational diffusion due to gadolinium's position at the center of the complex; and (4) the incorporation of 3 hydrophilic amino polyol pendant arms to ensure aqueous solubility, reduce binding with endogenous proteins, and enhance product safety.This rational design led to the creation of a first prototype, P03277V1. However, the occurrence of nephrogenic systemic fibrosis necessitated modifications to the Drug Target Profile, aimed at improving the complex's stability and reducing production costs. This was achieved through the discovery of an isomerization process for P03277V1, resulting in gadopiclenol, which demonstrated excellent kinetic stability.The rational design of gadopiclenol thus exemplifies the concept of Property-Based Drug Design used in medicinal chemistry. It also highlights that the complexity of designing a diagnostic agent is comparable to that of a therapeutic agent. Furthermore, the case of gadopiclenol illustrates that the medical positioning of a drug candidate can evolve during clinical development. Gadopiclenol's medical positioning shifted from being a product with high relaxivity to improve signal strength, to one intended for use at a half dose to limit gadolinium injection and minimize risks to patients, such as nephrogenic systemic fibrosis or accumulation in specific areas of the brain. Currently, gadopiclenol is approved for clinical use at a dose of 0.05 mmol/kg to minimize gadolinium exposure to patients. Whether the 0.1 mmol/kg dose can be used to enhance clinical diagnostics and improve patient management in the future remains to be seen.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":""},"PeriodicalIF":7.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143604818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}