Investigative Radiology最新文献

{"title":"Re: Assessing the Association Between Gadolinium-based Contrast Agents and Parkinson Disease: Insights from the Korean National Health Insurance Service Database.","authors":"Won-Jin Moon, Yun Jung Bae, Jong-Min Kim","doi":"10.1097/RLI.0000000000001183","DOIUrl":"10.1097/RLI.0000000000001183","url":null,"abstract":"","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"495-496"},"PeriodicalIF":7.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143772395","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":"Methodological Concerns Regarding the Association Between Gadolinium-Based Contrast Agents and Parkinson Disease.","authors":"Seong Ho Jeong, Hyungwoo Ahn, Eui Jin Hwang, Soon Ho Yoon, Jin Mo Goo","doi":"10.1097/RLI.0000000000001181","DOIUrl":"10.1097/RLI.0000000000001181","url":null,"abstract":"","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"493-494"},"PeriodicalIF":7.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143779973","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":"Deep Learning-Based Signal Amplification of T1-Weighted Single-Dose Images Improves Metastasis Detection in Brain MRI.","authors":"Robert Haase, Thomas Pinetz, Erich Kobler, Zeynep Bendella, Stefan Zülow, Arndt-Hendrik Schievelkamp, Frederic Carsten Schmeel, Sarah Panahabadi, Anna Magdalena Stylianou, Daniel Paech, Martha Foltyn-Dumitru, Verena Wagner, Kai Schlamp, Gudula Heussel, Mathias Holtkamp, Claus Peter Heussel, Martin Vahlensieck, Julian A Luetkens, Heinz-Peter Schlemmer, Johannes Haubold, Alexander Radbruch, Alexander Effland, Cornelius Deuschl, Katerina Deike","doi":"10.1097/RLI.0000000000001166","DOIUrl":"10.1097/RLI.0000000000001166","url":null,"abstract":"<p><strong>Objectives: </strong>Double-dose contrast-enhanced brain imaging improves tumor delineation and detection of occult metastases but is limited by concerns about gadolinium-based contrast agents' effects on patients and the environment. The purpose of this study was to test the benefit of a deep learning-based contrast signal amplification in true single-dose T1-weighted (T-SD) images creating artificial double-dose (A-DD) images for metastasis detection in brain magnetic resonance imaging.</p><p><strong>Materials and methods: </strong>In this prospective, multicenter study, a deep learning-based method originally trained on noncontrast, low-dose, and T-SD brain images was applied to T-SD images of 30 participants (mean age ± SD, 58.5 ± 11.8 years; 23 women) acquired externally between November 2022 and June 2023. Four readers with different levels of experience independently reviewed T-SD and A-DD images for metastases with 4 weeks between readings. A reference reader reviewed additionally acquired true double-dose images to determine any metastases present. Performances were compared using Mid-p McNemar tests for sensitivity and Wilcoxon signed rank tests for false-positive findings.</p><p><strong>Results: </strong>All readers found more metastases using A-DD images. The 2 experienced neuroradiologists achieved the same level of sensitivity using T-SD images (62 of 91 metastases, 68.1%). While the increase in sensitivity using A-DD images was only descriptive for 1 of them (A-DD: 65 of 91 metastases, +3.3%, P = 0.424), the second neuroradiologist benefited significantly with a sensitivity increase of 12.1% (73 of 91 metastases, P = 0.008). The 2 less experienced readers (1 resident and 1 fellow) both found significantly more metastases on A-DD images (resident, T-SD: 61.5%, A-DD: 68.1%, P = 0.039; fellow, T-SD: 58.2%, A-DD: 70.3%, P = 0.008). They were therefore able to use A-DD images to increase their sensitivity to the neuroradiologists' initial level on regular T-SD images. False-positive findings did not differ significantly between sequences. However, readers showed descriptively more false-positive findings on A-DD images. The benefit in sensitivity particularly applied to metastases ≤5 mm (5.7%-17.3% increase in sensitivity).</p><p><strong>Conclusions: </strong>A-DD images can improve the detectability of brain metastases without a significant loss of precision and could therefore represent a potentially valuable addition to regular single-dose brain imaging.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"543-551"},"PeriodicalIF":7.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143441008","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":"In Vivo Bone Mineral Density Assessment With Spectral Localizer Radiographs From Photon-Counting Detector CT: Prospective Comparison With DXA.","authors":"Lukas Jakob Moser, Konstantin Klambauer, Maria Carolina Diaz Machicado, Diana Frey, Victor Mergen, Matthias Eberhard, Tristan Nowak, Bernhard Schmidt, Thomas Flohr, Oliver Distler, Hatem Alkadhi","doi":"10.1097/RLI.0000000000001159","DOIUrl":"10.1097/RLI.0000000000001159","url":null,"abstract":"<p><strong>Purpose: </strong>The aim of this study was to determine in a prospective patient study the accuracy of areal bone mineral density (aBMD) measurements with spectral localizer radiographs obtained with a clinical photon-counting detector computed tomography (PCD-CT) scanner in comparison with dual-energy x-ray absorptiometry (DXA).</p><p><strong>Methods: </strong>In this institutional review board-approved, prospective study, 41 patients (15 females, 26 males; mean age 61.3 years, age range 35-78 years) underwent PCD-CT of the abdomen with a spectral localizer radiograph (tube voltage 140 kVp, tube current 30 mA) and DXA within a median of 45 days. aBMD values were derived for lumbar vertebrae L1-L4 from both methods and were compared with linear regression, Pearson correlation, intraclass correlation coefficients (ICCs), and Bland-Altman plots. T-scores were calculated on a patient level and were compared between methods.</p><p><strong>Results: </strong>DXA and spectral localizer radiographs showed strong correlation in aBMD measurements ( R = 0.97, P < 0.001) and patient level T-scores ( R = 0.99, P < 0.001). There was a strong agreement between aBMD from both methods (ICC, 0.96; 95% CI, 0.94-0.97). Bland-Altman analysis revealed a very small mean difference in aBMD between methods (mean absolute error 0.019 g/cm 2 ) with narrow limits of agreement (-0.083 g/cm 2 to 0.121 g/cm 2 ). Similarly, there were small differences in regard to the T-score (mean absolute error 0.156) with narrow limits of agreement (-0.422 to 0.734) between methods. ICCs indicated an excellent agreement between T-scores from DXA and spectral localizer radiographs (ICC, 0.98; 95% confidence interval, 0.95-0.99).</p><p><strong>Conclusions: </strong>Our prospective patient study indicates that spectral localizer radiographs obtained with a clinical PCD-CT system enable accurate quantification of the lumbar bone areal mineral density. This opens up the opportunity for opportunistic screening of osteoporosis in patients who undergo CT for other indications.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"535-542"},"PeriodicalIF":7.0,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12233169/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143123082","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":"Artifact Reduction in Interventional Devices Using Virtual Monoenergetic Images and Iterative Metal Artifact Reduction on Photon-Counting Detector CT.","authors":"Yannik Christian Layer, Sebastian Faby, Viktor Haase, Bernhard Schmidt, Narine Mesropyan, Patrick A Kupczyk, Alexander Isaak, Tatjana Dell, Julian A Luetkens, Daniel Kuetting","doi":"10.1097/RLI.0000000000001149","DOIUrl":"10.1097/RLI.0000000000001149","url":null,"abstract":"<p><strong>Objectives: </strong>The aim of this study was to assess the impact of an iterative metal artifact reduction (iMAR) algorithm combined with virtual monoenergetic images (VMIs) for artifact reduction in photon-counting detector computed tomography (PCDCT) during interventions.</p><p><strong>Materials and methods: </strong>Using an abdominal phantom, we conducted evaluations on the efficacy of iMAR and VMIs for mitigating image artifacts during interventions on a PCDCT. Four different puncture devices were employed under 2 scan modes (QuantumSn at 100 kV, Quantumplus at 140 kV) to simulate various clinical scenarios. Image reconstructions were initially performed without iMAR and subsequently with iMAR settings. The latter was tested with 7 different metal presets for each case. Furthermore, iMAR-reconstructed images were paired with VMIs at energy levels of 70 keV, 110 keV, 150 keV, and 190 keV. Qualitative assessments were conducted to evaluate image quality, artifact expression, and the emergence of new artifacts using a Likert scale. Image quality was rated on a scale of 1 (nondiagnostic) to 5 (excellent), whereas artifact severity was rated from 0 (none) to 5 (massive). Preferences for specific iMAR presets were documented. Quantitative analysis involved calculating Hounsfield unit (HU) differences between artifact-rich and artifact-free tissues.</p><p><strong>Results: </strong>Overall, 96 different scanning series were evaluated. The optimal combination for artifact reduction was found to be iMAR neurocoils with VMIs at 150 keV and 190 keV, showcasing the most substantial reduction in artifacts with a median rating of 1 (standard: 4). VMIs at higher keV levels, such as 190 keV, resulted in reduced image quality, as indicated by a median rating of 3 (compared with 70 keV with a median of 5). Newly emerged artifact expression related to reconstructions varied among intervention devices, with iMAR thoracic coils exhibiting the least extent of artifacts (median: 2) and iMAR neurocoils displaying the most pronounced artifacts (median: 4). Qualitative analysis favored the combination of iMAR neurocoils with VMIs at 70 keV, showcasing the best results. Conversely, quantitative analysis revealed that the combination of iMAR neurocoils with VMIs at 190 keV yielded the best results, with an average artifact expression of 20.06 HU (standard: 167.98 HU; P < 0.0001).</p><p><strong>Conclusions: </strong>The study underscores a substantial reduction in artifacts associated with intervention devices during PCDCT scans through the synergistic application of VMI and iMAR techniques. Specifically, the combination of VMIs at 70 keV with iMAR neurocoils was preferred, leading to enhanced diagnostic assessability of surrounding tissues and target lesions. The study demonstrates the potential of iMAR and VMIs for PCDCT-guided interventions. These advancements could improve accuracy, safety, efficiency, and patient outcomes in clinical practice.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"463-469"},"PeriodicalIF":7.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142921310","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":"Audiovisual Breathing Guidance for Improved Image Quality and Scan Efficiency of T2- and Diffusion-Weighted Liver MRI.","authors":"Narine Mesropyan, Christoph Katemann, Annerieke Heuvelink-Marck, Can Yüksel, Alexander Isaak, Asadeh Lakghomi, Leon Bischoff, Tatjana Dell, Dmitrij Kravchenko, Daniel Kuetting, Claus C Pieper, Julian A Luetkens","doi":"10.1097/RLI.0000000000001150","DOIUrl":"10.1097/RLI.0000000000001150","url":null,"abstract":"<p><strong>Objectives: </strong>Impaired image quality and long scan times frequently occur in respiratory-triggered sequences in liver magnetic resonance imaging (MRI). We evaluated the impact of an in-bore active breathing guidance (BG) application on image quality and scan time of respiratory-triggered T2-weighted (T2) and diffusion-weighted imaging (DWI) by comparing sequences with standard triggering (T2 S and DWI S ) and with BG (T2 BG and DWI BG ).</p><p><strong>Materials and methods: </strong>In this prospective study, random patients with clinical indications for liver MRI underwent 3 T MRI with standard and BG acquisitions. The audiovisual BG application received the respiratory signal from the scanner, and animated breathing instructions were displayed using a mirror and screen behind the MRI bore. Prior to the DWI BG and T2 BG acquisition, patients received a short video instruction about MRI with BG. Suitable parameters for desired breathing pattern for T2 BG and DWI BG were set individually for each patient based on the patient's physical respiratory ability (ie, 4 seconds breathing followed by 4.5 seconds breath holding). Artifacts, sharpness, lesion conspicuity, and overall image quality were assessed using a Likert scale from 1 (nondiagnostic) to 5 (excellent). Scan time, apparent contrast-to-noise ratio, and apparent signal-to-noise ratio (aSNR) for all sequences were analyzed. Paired t test and Wilcoxon test were used for statistical analysis.</p><p><strong>Results: </strong>Thirty-two patients (mean age: 55 ± 13 years, 13 female) were included. T2 BG showed less artifacts (4.5 ± 0.7 vs 4.1 ± 0.8, P < 0.001) and better sharpness, lesion conspicuity, and overall image quality (eg, overall image quality 4.6 ± 0.7 vs 4.4 ± 0.7, P = 0.004) compared with T2 S . DWI BG demonstrated improved image quality in all categories compared with DWI S (eg, overall image quality 4.5 ± 0.5 vs 4.3 ± 0.5, P = 0.005) and less artifacts (4.1 ± 0.5 vs 3.8 ± 0.7, P = 0.007). Scan times of T2 BG (286 ± 23 vs 345 ± 68 seconds, P < 0.001) and DWI BG (160 ± 4 vs 252 ± 70 seconds, P < 0.001) were reduced by 17% and 37%, respectively. aSNR and apparent contrast-to-noise ratio (eg, aSNR: 23.45 ± 11.31 [T2 BG ] vs 25.84 ± 10.76 [T2 S ]; P = 0.079) were similar for both sequences for both approaches.</p><p><strong>Conclusions: </strong>Active BG for respiratory-triggered liver T2w and DWI sequences led to significant reduction of breathing artifacts, improved image quality, and shorter scan time compared with standard acquisitions.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"470-477"},"PeriodicalIF":7.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142977747","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":"High-Resolution Free-Breathing Chemical-Shift-Encoded MRI for Characterizing Lymph Nodes in the Upper Abdomen.","authors":"Ivo T Maatman, Marnix C Maas, Sjoerd Ypma, Tobias K Block, Rik van den Elshout, Andor Veltien, Ewoud J Smit, John J Hermans, Tom W J Scheenen","doi":"10.1097/RLI.0000000000001147","DOIUrl":"10.1097/RLI.0000000000001147","url":null,"abstract":"<p><strong>Objectives: </strong>Accurate lymph node (LN) staging is crucial for managing upper abdominal cancers. Ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging effectively distinguishes healthy and metastatic LNs through fat/water and -weighted imaging. However, respiratory motion artifacts complicate detection of abdominal LNs. This study evaluates if a free-breathing radial stack-of-stars acquisition can match or outperform Cartesian reference scans to visualize LNs and depict uptake of USPIO nanoparticles.</p><p><strong>Materials and methods: </strong>Five volunteers with USPIO and 20 patients without USPIO were scanned using radial stack-of-stars, Cartesian dual-echo, and fat-saturated Cartesian multiecho sequences for fat/water imaging and estimation. Reconstructed images from radial and Cartesian patient data underwent qualitative comparison by 2 radiologists. LNs were identified in all fat/water images, LN short-axis sizes were measured, and relaxation rates were analyzed using linear correlations and Bland-Altman plots.</p><p><strong>Results: </strong>Radial imaging provided better image quality than the Cartesian reference standard, according to both readers. Substantially, more LNs were identified in radial compared with Cartesian datasets (349 vs 202). Median short-axis diameters showed a significant difference, measuring 2.7 mm (interquartile range [IQR]: 2.7-4.6 mm) for radial images and 4.5 mm (IQR: 3.7-5.6 mm) for Cartesian images ( P < 0.0001). Relaxation rates measured in radial data showed a significant linear correlation with the Cartesian reference (Pearson correlation coefficient: 0.90 with P < 0.0001). Bland-Altman plots indicated a slight bias with a mean difference (MD) of 3.9 s -1 and limits of agreement at MD ± 16.4 s -1 .</p><p><strong>Conclusions: </strong>This work presents a promising magnetic resonance imaging method to depict upper abdominal LNs and to visualize their USPIO uptake. Instead of multiple Cartesian breath-hold scans, all relevant contrasts and parameters are obtained from a single free-breathing radial acquisition. The proposed method yielded higher image quality and more sensitive detection of small LNs. value analysis showed a strong linear correlation with the reference, albeit with minimal biases.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":"60 7","pages":"434-443"},"PeriodicalIF":7.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144234021","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":"Motion-Compensated Multishot Pancreatic Diffusion-Weighted Imaging With Deep Learning-Based Denoising.","authors":"Kang Wang, Matthew J Middione, Andreas M Loening, Ali B Syed, Ariel J Hannum, Xinzeng Wang, Arnaud Guidon, Patricia Lan, Daniel B Ennis, Ryan L Brunsing","doi":"10.1097/RLI.0000000000001148","DOIUrl":"10.1097/RLI.0000000000001148","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Objectives: &lt;/strong&gt;Pancreatic diffusion-weighted imaging (DWI) has numerous clinical applications, but conventional single-shot methods suffer from off resonance-induced artifacts like distortion and blurring while cardiovascular motion-induced phase inconsistency leads to quantitative errors and signal loss, limiting its utility. Multishot DWI (msDWI) offers reduced image distortion and blurring relative to single-shot methods but increases sensitivity to motion artifacts. Motion-compensated diffusion-encoding gradients (MCGs) reduce motion artifacts and could improve motion robustness of msDWI but come with the cost of extended echo time, further reducing signal. Thus, a method that combines msDWI with MCGs while minimizing the echo time penalty and maximizing signal would improve pancreatic DWI. In this work, we combine MCGs generated via convex-optimized diffusion encoding (CODE), which reduces the echo time penalty of motion compensation, with deep learning (DL)-based denoising to address residual signal loss. We hypothesize this method will qualitatively and quantitatively improve msDWI of the pancreas.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Materials and methods: &lt;/strong&gt;This prospective institutional review board-approved study included 22 patients who underwent abdominal MR examinations from August 22, 2022 and May 17, 2023 on 3.0 T scanners. Following informed consent, 2-shot spin-echo echo-planar DWI (b = 0, 800 s/mm 2 ) without (M0) and with (M1) CODE-generated first-order gradient moment nulling was added to their clinical examinations. DL-based denoising was applied to the M1 images (M1 + DL) off-line. ADC maps were reconstructed for all 3 methods. Blinded pair-wise comparisons of b = 800 s/mm 2 images were done by 3 subspecialist radiologists. Five metrics were compared: pancreatic boundary delineation, motion artifacts, signal homogeneity, perceived noise, and diagnostic preference. Regions of interest of the pancreatic head, body, and tail were drawn, and mean ADC values were computed. Repeated analysis of variance and post hoc pairwise t test with Bonferroni correction were used for comparing mean ADC values. Bland-Altman analysis compared mean ADC values. Reader preferences were tabulated and compared using Wilcoxon signed rank test with Bonferroni correction and Fleiss κ.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;M1 was significantly preferred over M0 for perceived motion artifacts and signal homogeneity ( P &lt; 0.001). M0 was significantly preferred over M1 for perceived noise ( P &lt; 0.001), but DL-based denoising (M1 + DL) reversed this trend and was significantly favored over M0 ( P &lt; 0.001). ADC measurements from M0 varied between different regions of the pancreas ( P = 0.001), whereas motion correction with M1 and M1 + DL resulted in homogeneous ADC values ( P = 0.24), with values similar to those reported for ssDWI with motion correction. ADC values from M0 were significantly higher than M1 in the head (bias 16.6%; P &lt; 0.0001), body (bias 11.0%","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"444-453"},"PeriodicalIF":7.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143005273","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":"Gadolinium Elimination in a Gadolinium Deposition Disease Population After a Single Exposure to Gadolinium-Based Contrast Agents.","authors":"Joana Ramalho, Miguel Ramalho, Richard C Semelka","doi":"10.1097/RLI.0000000000001146","DOIUrl":"10.1097/RLI.0000000000001146","url":null,"abstract":"<p><strong>Purpose: </strong>This study documents the gadolinium (Gd) content in urine over time after the administration of a single dose of Gd-based contrast agent (GBCA) in patients diagnosed with Gd deposition disease.</p><p><strong>Materials and methods: </strong>In this retrospective observational study, 45 subjects with normal renal function who had performed 1 contrast-enhanced magnetic resonance imaging and had a nonprovoked (native) 24-hour urine test for Gd quantification after the examination were evaluated. The GBCA brand and the time interval in days between the GBCA administration and 24-hour urine Gd measurements were recorded. Log-log plot visualization of time points for urine Gd content was obtained.</p><p><strong>Results: </strong>Time points collected for urine Gd content showed that Gd was above the reference levels for 3 months postinjection. The urinary concentration of Gd was similar for all agents, including linear and macrocyclic. The urinary content decreased in a dog-leg fashion. Gd urine content was substantially elevated at 1 month and decreased to remain above the accepted normal range by 3 months.</p><p><strong>Conclusions: </strong>Gd is retained in the body and shows demonstrable continued spontaneous elimination in urine for at least several months after administration, including the most stable macrocyclic agents. The Gd elimination pattern shows a logarithmic decrease pattern between 1 and 3 months for all agents, regardless of their structure.</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"429-433"},"PeriodicalIF":7.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142785464","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":"Intraindividual Comparison of Image Quality Between Low-Dose and Ultra-Low-Dose Abdominal CT With Deep Learning Reconstruction and Standard-Dose Abdominal CT Using Dual-Split Scan.","authors":"Tae Young Lee, Jeong Hee Yoon, Jin Young Park, So Hyun Park, HeeSoo Kim, Chul-Min Lee, Yunhee Choi, Jeong Min Lee","doi":"10.1097/RLI.0000000000001151","DOIUrl":"10.1097/RLI.0000000000001151","url":null,"abstract":"<p><strong>Objective: </strong>The aim of this study was to intraindividually compare the conspicuity of focal liver lesions (FLLs) between low- and ultra-low-dose computed tomography (CT) with deep learning reconstruction (DLR) and standard-dose CT with model-based iterative reconstruction (MBIR) from a single CT using dual-split scan in patients with suspected liver metastasis via a noninferiority design.</p><p><strong>Materials and methods: </strong>This prospective study enrolled participants who met the eligibility criteria at 2 tertiary hospitals in South Korea from June 2022 to January 2023. The criteria included ( a ) being aged between 20 and 85 years and ( b ) having suspected or known liver metastases. Dual-source CT scans were conducted, with the standard radiation dose divided in a 2:1 ratio between tubes A and B (67% and 33%, respectively). The voltage settings of 100/120 kVp were selected based on the participant's body mass index (<30 vs ≥30 kg/m 2 ). For image reconstruction, MBIR was utilized for standard-dose (100%) images, whereas DLR was employed for both low-dose (67%) and ultra-low-dose (33%) images. Three radiologists independently evaluated FLL conspicuity, the probability of metastasis, and subjective image quality using a 5-point Likert scale, in addition to quantitative signal-to-noise and contrast-to-noise ratios. The noninferiority margins were set at -0.5 for conspicuity and -0.1 for detection.</p><p><strong>Results: </strong>One hundred thirty-three participants (male = 58, mean body mass index = 23.0 ± 3.4 kg/m 2 ) were included in the analysis. The low- and ultra-low- dose had a lower radiation dose than the standard-dose (median CT dose index volume: 3.75, 1.87 vs 5.62 mGy, respectively, in the arterial phase; 3.89, 1.95 vs 5.84 in the portal venous phase, P < 0.001 for all). Median FLL conspicuity was lower in the low- and ultra-low-dose scans compared with the standard-dose (3.0 [interquartile range, IQR: 2.0, 4.0], 3.0 [IQR: 1.0, 4.0] vs 3.0 [IQR: 2.0, 4.0] in the arterial phase; 4.0 [IQR: 1.0, 5.0], 3.0 [IQR: 1.0, 4.0] vs 4.0 [IQR: 2.0, 5.0] in the portal venous phases), yet within the noninferiority margin ( P < 0.001 for all). FLL detection was also lower but remained within the margin (lesion detection rate: 0.772 [95% confidence interval, CI: 0.727, 0.812], 0.754 [0.708, 0.795], respectively) compared with the standard-dose (0.810 [95% CI: 0.770, 0.844]). Sensitivity for liver metastasis differed between the standard- (80.6% [95% CI: 76.0, 84.5]), low-, and ultra-low-doses (75.7% [95% CI: 70.2, 80.5], 73.7 [95% CI: 68.3, 78.5], respectively, P < 0.001 for both), whereas specificity was similar ( P > 0.05).</p><p><strong>Conclusions: </strong>Low- and ultra-low-dose CT with DLR showed noninferior FLL conspicuity and detection compared with standard-dose CT with MBIR. Caution is needed due to a potential decrease in sensitivity for metastasis ( clinicaltrials.gov/NCT05324046 ).</p>","PeriodicalId":14486,"journal":{"name":"Investigative Radiology","volume":" ","pages":"454-462"},"PeriodicalIF":7.9,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143058900","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}