BACKGROUND: Coronary microvascular dysfunction (CMD) is a major contributor to cardiovascular complications in diabetes. Although noninvasive techniques such as arterial spin labeling cardiac MRI (ASL-MRI) and transthora...BACKGROUND: Coronary microvascular dysfunction (CMD) is a major contributor to cardiovascular complications in diabetes. Although noninvasive techniques such as arterial spin labeling cardiac MRI (ASL-MRI) and transthoracic echocardiography (TTE) are available, their comparative performance for CMD remains unclear. PURPOSE: To compare ASL-MRI and TTE for CMD assessment in type 1 and type 2 (T1DM, T2DM) mouse models and relate functional indices to histological microvascular and myocardial remodeling, including early-stage T2DM (8w-T2DM). STUDY TYPE: Prospective. ANIMAL MODEL: Forty 8-week-old male C57BL/6J mice allocated to five groups: control, T1DM, and T2DM (n = 10 per group, imaged 16 weeks postinduction), and early-stage T2DM (8w-T2DM) and age-matched controls (n = 5 per group, imaged 8 weeks post-induction). FIELD STRENGTH/SEQUENCE: Segmented FLASH cine, steady-pulsed labeling ASL, and inversion-recovery segmented FLASH (T1 mapping) sequences at 9.4 T. ASSESSMENT: Rest/stress myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) were derived from ASL data using a model-based approach incorporating native T1 (from segmented FLASH data). Coronary flow velocity (CFV) and reserve (CFVR) were measured by TTE at rest (1.5% isoflurane) and stress (2.5% isoflurane). Histology included assessment of hematoxylin-eosin (myocyte area), Masson (collagen), and IB4 (capillary density). STATISTICAL TESTS: Group comparisons used t-tests, Mann-Whitney U tests, and one-/two-way ANOVA with Bonferroni correction; correlations were assessed with Pearson or Spearman coefficients (r). p < 0.05 was considered significant. RESULTS: 38 animals completed MR and TTE imaging. At 16 weeks, stress diastolic MBF was significantly lower in T1DM (14.67 ± 1.62 mL/g/min) and T2DM (13.42 ± 2.44 mL/g/min) vs. controls (22.19 ± 0.25 mL/g/min), with significantly reduced MPR in T2DM (1.53 ± 0.17 vs. 2.27 ± 0.15). TTE showed significantly reduced CFVR only in T2DM (2.16 ± 0.24 vs. 2.75 ± 0.24). In 8w-T2DM, ASL-MRI detected significantly reduced MPR (1.87 ± 0.16 vs. 2.26 ± 0.13), whereas TTE showed no significant CFVR change (p = 0.900). Capillary density significantly decreased in 16-week and 8-week T2DM. IB4-positive area correlated with CFVR (r = 0.673) and more strongly with MPR (r = 0.810). CONCLUSION: ASL-MRI detected CMD in diabetic mice, outperforming TTE in early-stage disease and showing a strong association with microvascular injury. EVIDENCE LEVEL: 1. TECHNICAL EFFICACY: Stage 2.
Sigmund EE, Rauh SS, Iima M
… +21 more, Federau C, Hernando D, Jalnefjord O, Jansen JFA, Jasse J, Jerome NP, Kaandorp MPT, Kurugol S, Laun FB, Liu MM, Ljimani A, Niendorf T, Reiter DA, Shazeeb MS, Shukla-Dave A, Stabinska J, Wetscherek A, While PT, Wu D, Le Bihan D, Gurney-Champion OJ
J Magn Reson Imaging
· 2026 Jun · PMID 41853873
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Intravoxel incoherent motion (IVIM) MRI allows for simultaneous assessment of tissue microcirculation (perfusion) and diffusion of water. In single-center studies, IVIM has shown great potential for diagnosis, treatment...Intravoxel incoherent motion (IVIM) MRI allows for simultaneous assessment of tissue microcirculation (perfusion) and diffusion of water. In single-center studies, IVIM has shown great potential for diagnosis, treatment outcome prediction, and treatment monitoring for many different diseases and organs. However, heterogeneity in data acquisition protocols, pre-processing pipelines, and post-processing routines yields differences in reported IVIM parameters, which has constrained large-scale deployment of IVIM. Moreover, deploying IVIM protocols and analysis typically requires technical expertise, further challenging wider use, especially for clinicians. In this consensus paper, to accelerate the deployment of IVIM, we provide recommendations and harmonize protocols for brain, breast, kidney, liver, muscle, and pancreas IVIM studies. For this goal we organized multiple questionnaires and held a dedicated workshop. To ensure a level of standardized, reproducible results, without restricting innovation, we suggest a small subset of b-values to always be measured and analyzed separately, and to which more extensive b-value sampling can be added for advanced investigations. We further introduce detailed recommendations on acquisition protocols and analysis pipelines. To increase consistency, repeatability, and reproducibility, we highly recommend that these protocols and pipelines be deployed by scientists and clinicians for IVIM studies. For advanced users who desire different protocols or analysis approaches, we suggest adding results from our suggested protocols and analysis pipeline in the supplemental part of their paper to enable retrospective studies.
Zecca V, Palombelli G, Vanacore N
… +1 more, Canese R
J Magn Reson Imaging
· 2026 Jun · PMID 41852095
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Alzheimer's disease (AD) is one of the most common neurological disorders affecting older adults, with approximately 7.2 million cases only in the United States. This number is projected to increase to 13.8 million in th...Alzheimer's disease (AD) is one of the most common neurological disorders affecting older adults, with approximately 7.2 million cases only in the United States. This number is projected to increase to 13.8 million in the United States by 2060, leading to increased expenditures for healthcare, long-term care and hospice services. Consequently, great emphasis is placed on prevention and the development of early diagnosis techniques, which can lead to timely treatment and the prevention of the consequences of full-blown disease. In this review, we analyze the potential diagnostic value of biomarkers derived from a multimodal approach based on magnetic resonance spectroscopy, diffusion tensor imaging, and magnetic resonance imaging, capable of detecting metabolic, microstructural, and anatomical changes, respectively, that precede the cognitive and behavioral changes observed in AD by years. The primary aim is to evaluate whether the combined and complementary use of these methods can identify early biomarkers useful for recognizing AD in its early stages, predicting progression from MCI to AD, supporting patient stratification, and monitoring cognitive decline or response to treatment. We identified regions more susceptible to metabolic alterations (PCC and hippocampus) and trajectories of structural brain alterations (atrophy or diffusivity abnormalities). The assessment of such imaging biomarkers may serve as the foundation for future prospective studies aimed at developing differential diagnostic methods, a crucial goal within the broader context of dementias, by adopting standardized multimodal MRI protocols. EVIDENCE LEVEL: 3. TECHNICAL EFFICACY: Stage 1.
BACKGROUND: Noninvasive detection of glomerular hyperfiltration, a key driver of diabetic nephropathy (DN), is needed for timely intervention (e.g., dapagliflozin), as is early DN identification to guide therapy. PURPOSE...BACKGROUND: Noninvasive detection of glomerular hyperfiltration, a key driver of diabetic nephropathy (DN), is needed for timely intervention (e.g., dapagliflozin), as is early DN identification to guide therapy. PURPOSE: To evaluate MR elastography (MRE) for detecting glomerular hyperfiltration and early DN, using glomerular filtration rate (GFR) and pathology as reference standards. STUDY TYPE: Animal proof of concept. ANIMAL MODEL: Ninety-five male Sprague-Dawley rats (80 with high-fat diet and low-dose streptozotocin-induced type 2 diabetes and 15 normal controls). FIELD STRENGTH/SEQUENCE: Briefly, 3.0 T; a multifrequency (100, 150, and 200 Hz) three-dimensional MRE sequence and a multi-b-value (0-800 s/mm) intravoxel incoherent motion (IVIM) sequence. ASSESSMENT: MRE-derived shear stiffness (SS) and loss modulus (LM) and IVIM-derived true diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) were measured. Glomerular hyperfiltration and DN classes were diagnosed by direct GFR measurement and renal pathology. Ex vivo rheometry validated MRE-derived viscoelastic parameters. STATISTICAL TESTS: Linear mixed-effects models; one-way analysis of variance (ANOVA) or Welch's ANOVA; Pearson correlation; intraclass correlation coefficient (ICC); area under the receiver operating characteristic curve (AUC) and DeLong's test. p < 0.05 was considered significant. RESULTS: Renal SS was significantly higher in hyperfiltration than in controls and early DN (class I-II), distinguishing hyperfiltration from controls (AUC = 0.94) and from early DN (AUC = 0.90). LM was elevated in hyperfiltration but did not decrease significantly in early DN (p > 0.99 vs. hyperfiltration). IVIM parameters showed limited diagnostic utility (AUCs: 0.53-0.72). Dapagliflozin treatment normalized the elevated SS and LM in diabetic rats. Ex vivo rheometry showed significant positive correlations with MRE-derived SS and LM. DATA CONCLUSION: Three-dimensional MRE-derived renal SS is a potential noninvasive biomarker to detect diabetic glomerular hyperfiltration, monitor response to dapagliflozin therapy, and enable early identification of DN. EVIDENCE LEVEL: 1. TECHNICAL EFFICACY: Stage 2.
BACKGROUND: Biparametric MRI (bpMRI) was interpreted using Prostate Imaging Reporting and Data System (PI-RADS) version 2.1, a system associated with relatively low specificity. Selective size imaging using filters via d...BACKGROUND: Biparametric MRI (bpMRI) was interpreted using Prostate Imaging Reporting and Data System (PI-RADS) version 2.1, a system associated with relatively low specificity. Selective size imaging using filters via diffusion times MRI (SSIFT-MRI) is a novel imaging technique that may improve diagnostic performance. PURPOSE: To compare the diagnostic performance of bpMRI versus SSIFT-MRI for diagnosing clinically significant prostate cancer (csPCa). STUDY TYPE: Prospective. POPULATION: Hundred and eighteen men (age: 70 ± 7 years) with suspected csPCa. FIELD STRENGTH/SEQUENCE: Pulsed and oscillating gradient spin-echo sequences at 3 T. BpMRI included three-plane T2-weighted imaging and diffusion-weighted imaging. ASSESSMENT: csPCa status was pathologically determined via ultrasound-guided biopsy or prostatectomy. Three radiologists assessed bpMRI and SSIFT-MRI for identifying csPCa lesions, and we further compared the performance of combining PI-RADS with SSIFT-MRI against that of bpMRI. STATISTICAL TESTS: Area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for diagnostic performance; bootstrap resampling for comparing AUC; McNemar's test for comparing sensitivity, specificity, PPV, NPV, and accuracy. A p-value < 0.05 was considered significant. RESULTS: Per-patient accuracy was significantly higher for SSIFT-MRI (reader 1: 85% vs. 68%; reader 2: 80% vs. 64%; reader 3: 77% vs. 65%). Per-patient specificity (reader 1: 71% vs. 27%; reader 2: 58% vs. 11%; reader 3: 58% vs. 20%) and PPV (reader 1: 84% vs. 67%; reader 2: 78% vs. 64%; reader 3: 77% vs. 65%) were significantly higher for SSIFT-MRI. Combining PI-RADS with SSIFT-MRI yielded significantly higher AUCs and accuracy than bpMRI alone (AUC and accuracy for reader 1: 0.89% and 83%; reader 2: 0.80% and 73%; reader 3: 0.75% and 72%). DATA CONCLUSION: SSIFT-MRI for csPCa had similar or higher diagnostic performance compared with bpMRI. The combination approach provided significantly higher AUC and accuracy than bpMRI. EVIDENCE LEVEL: 1. STAGE OF TECHNICAL EFFICACY: 2.
BACKGROUND: Lumbar disc herniation (LDH) causes compositional alterations within compressed nerve roots, resulting in low back pain (LBP). The ultrashort echo time magnetization transfer technique (UTE-MT) facilitates as...BACKGROUND: Lumbar disc herniation (LDH) causes compositional alterations within compressed nerve roots, resulting in low back pain (LBP). The ultrashort echo time magnetization transfer technique (UTE-MT) facilitates assessment of macromolecular changes in collagen- or myelin-rich tissues in nerve roots. PURPOSE: To assess lumbar nerve root composition in LDH using UTE-MT. STUDY TYPE: Prospective. POPULATION: One hundred and seventy-six participants (age range, 20-89; 72 females) with LDH. FIELD STRENGTH/SEQUENCE: 3T/UTE-MT, Carr-Purcell-Meiboom-Gill (CPMG). ASSESSMENT: UTE-MT ratio (UTE-MTR) and T value in compressed nerve roots (determined on axial T) were evaluated by UTE-MT and CPMG in LDH patients (L4/5-L5/S1). Additionally, pain and functionality were evaluated using the visual analog scale (VAS) and Oswestry Disability Index (ODI). STATISTICAL TESTS: Linear regression and Bland-Altman assessed UTE-MT reproducibility. One-way ANOVA assessed the statistical significance of UTE-MTR and T measures between compressed and intact nerve roots. ROC and DCA evaluated diagnostic performance and clinical value of UTE-MTR and T in discriminating between compressed and intact nerve roots. Linear regression correlated UTE-MTR and T with pain and functionality scores. The p value < 0.05 was considered significant. RESULTS: Significant increases in UTE-MTR and decreases in T values in compressed nerve roots compared to intact ones. High AUC values for UTE-MTR (0.912 at L4/5 and 0.900 at L5/S1) highlighted its superior ability to distinguish between compressed and intact nerve roots, outperforming T (AUCs of 0.840 and 0.790, respectively) in cohort discrimination. Strong significant positive correlations were found between UTE-MTR and VAS (R = 0.63) and ODI (R = 0.62), while T values showed moderate significant negative correlations with VAS (R = 0.32) and ODI (R = 0.32) for the measurement of the most severely compressed nerve roots (determined on axial T). DATA CONCLUSION: UTE-MT technique can detect macromolecular alterations in the compressed nerve roots of patients diagnosed with LDH. TECHNICAL EFFICACY: Stage 2.
BACKGROUND: Bleeding risk assessment of esophageal varices (EVs) is commonly performed in liver cirrhosis. However, existing approaches are often invasive or insufficient to fully capture bleeding risk. PURPOSE: To inves...BACKGROUND: Bleeding risk assessment of esophageal varices (EVs) is commonly performed in liver cirrhosis. However, existing approaches are often invasive or insufficient to fully capture bleeding risk. PURPOSE: To investigate portal venous hemodynamics and vessel geometry associated with EVs severity in cirrhotic patients using four-dimensional flow MRI as a noninvasive approach to support clinical risk assessment. STUDY TYPE: Retrospective. POPULATION: One-hundred and four cirrhotic patients consisting of patients without EVs (Group 1, n = 48), with low-risk EVs (Group 2, n = 37), and high-risk EVs (Group 3, n = 19). FIELD STRENGTH/SEQUENCE: 3 T, a three-directional, velocity-encoded gradient echo sequence with Cartesian k-space sampling. ASSESSMENT: Flow rate, mean velocity, and fractional flow changes in main portal vein (PV); effective vessel diameter and vessel angle; and rotational flow including vorticity, helicity, helical flow intensity (h ), localized normalized helicity, and vortex volume. STATISTICAL TESTS: One-way ANOVA with Tukey's post hoc test or Kruskal-Wallis followed by Conover's post hoc test. Receiver operating characteristic (ROC) curve analysis. Significance level set at p < 0.05. RESULTS: Significant group differences were observed for flow rate at the proximal PV (ε = 0.05) and for mean PV velocity at both proximal (ε = 0.13) and distal locations (η = 0.11). In contrast, neither fractional portal venous flow nor vessel angle measurements differed across groups (p = 0.294 and all p ≥ 0.475, respectively). Among rotational flow biomarkers, vorticity differentiated Group 3 from both Groups 1 and 2 (Group 1: 17.86 ± 3.26 s, Group 2: 16.65 ± 4.58 s, Group 3: 13.59 ± 3.23 s; η = 0.15), with an area under the ROC curve of 0.77 (sensitivity = 0.79, specificity = 0.62). DATA CONCLUSION: Rotational flow biomarkers may support current risk assessment in cirrhotic patients with high-risk EVs. EVIDENCE LEVEL: 4. TECHNICAL EFFICACY: Stage 2.
BACKGROUND: Major adverse cardiovascular events (MACE) are a leading cause of morbidity and mortality in patients with end-stage renal disease (ESRD). However, risk stratification and prognostic prediction remain limited...BACKGROUND: Major adverse cardiovascular events (MACE) are a leading cause of morbidity and mortality in patients with end-stage renal disease (ESRD). However, risk stratification and prognostic prediction remain limited. PURPOSE: To assess the incremental prognostic value of combined left atrial (LA) and left ventricular (LV) strain in predicting MACE among ESRD patients receiving renal replacement therapy. STUDY TYPE: Prospective. POPULATION: Three hundred thirteen ESRD patients (mean age: 53.8 ± 14.0 years; 202 males) undergoing maintenance dialysis. FIELD STRENGTH/SEQUENCE: Balanced steady-state free precession (bSSFP) cine sequence at 3.0 T. ASSESSMENT: Myocardial strain was analyzed from bSSFP cine images using feature-tracking software (CVI42). LA strain components were reservoir (LARS), conduit (LAScd), and contractile (LASct) strain, and LV strain included global longitudinal (GLS), radial (GRS), and circumferential (GCS) strain. Patients were followed up via clinical records and MACE were documented. Prognostic models were constructed using multivariable Cox proportional hazards regression. The baseline prediction model of conventional cardiovascular risk factors was then compared with models incorporating LARS and GLS to assess incremental prognostic value. STATISTICAL TESTS: Cox proportional hazards regression identified predictors of MACE, and model performance was evaluated using C-index, Akaike and Bayesian information criteria (AIC/BIC), and Kaplan-Meier analysis. p < 0.05 was considered significant. RESULTS: During a median follow-up of 16.93 months, 61 patients developed MACE. LARS (hazard ratio (HR) 0.90, 95% confidence interval (CI) 0.87-0.94) and LV GLS (HR 1.21, 95% CI 1.08-1.36) were independent predictors. The Cox model incorporating both LARS and LV GLS showed improved discrimination compared with the clinical risk factor model (C-index 0.79 vs. 0.70). Stratification by both LA and LV strain markers significantly improved MACE prediction (log-rank: p < 0.001). DATA CONCLUSION: The integration of LA and LV strain offered superior prognostic value for MACE prediction in ESRD patients, enabling refined risk stratification beyond traditional measures. EVIDENCE LEVEL: 2. TECHNICAL EFFICACY: Stage 3.
Mandija S, Tha KK, Katoch N
… +12 more, Göksu C, Katscher U, Sadleir R, Jung KJ, Luo J, Giannakopoulos II, Kim DH, Shmueli K, Lattanzi R, Ider YZ, Thielscher A, van den Berg C
J Magn Reson Imaging
· 2026 May · PMID 41795132
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Magnetic resonance imaging (MRI) has emerged as a noninvasive technique for probing the electrical properties of biological tissues: electrical conductivity and relative permittivity. This review focuses on the electrica...Magnetic resonance imaging (MRI) has emerged as a noninvasive technique for probing the electrical properties of biological tissues: electrical conductivity and relative permittivity. This review focuses on the electrical conductivity and provides a comprehensive overview of applications across both low- and high-frequency regimes. At low frequencies (below 1 MHz), conductivity mapping primarily reflects tissue microstructure and ionic composition. In contrast, at high frequencies (around 100 MHz), tissue conductivity primarily reflects ionic composition. First, we summarize the theoretical foundations, technical developments, and reconstruction algorithms that underpin conductivity imaging, highlighting advances in magnetic resonance electrical impedance tomography, current density imaging, and electrical properties tomography. The main part of the article discusses preclinical and clinical applications, demonstrating the potential and possible roles of conductivity imaging in clinical settings, along with current challenges and emerging applications. Finally, we outline future directions toward integrating conductivity imaging into routine MRI protocols, with the potential to enhance diagnostic precision and therapeutic monitoring. EVIDENCE LEVEL: 1. TECHNICAL EFFICACY: Stage 3.
BACKGROUND: Although deep learning reconstruction (DLR) has been shown to improve image quality in MRI, its impact on quantitative physiologic parameters derived from diffusion-weighted imaging (DWI) and dynamic suscepti...BACKGROUND: Although deep learning reconstruction (DLR) has been shown to improve image quality in MRI, its impact on quantitative physiologic parameters derived from diffusion-weighted imaging (DWI) and dynamic susceptibility contrast (DSC) perfusion in brain tumor imaging remains unclear. PURPOSE: To evaluate the impact of DLR on quantitative parameters derived from DWI and DSC in patients with brain tumors. STUDY TYPE: Retrospective. SUBJECTS: Sixty-two patients (33 male) with post-radiation brain metastasis. FIELD STRENGTH/SEQUENCE: 3.0 T; T2, FLAIR, T1WI, DWI, DSC perfusion, and contrast-enhanced T1WI. ASSESSMENT: DWI and DSC images were reconstructed at three DLR levels (high, medium, and low). Agreement between original and DLR images for apparent diffusion coefficient (ADC), cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to peak (TTP) was assessed using the coefficient of variation, repeatability coefficient (RC), and concordance correlation coefficient. For DSC time-series, signal-to-noise ratio, root mean square error (RMSE), and mean absolute error (MAE) were computed within tumor masks. DWI comparisons used mean signal intensity at b = 0 and b = 1000. STATISTICAL TESTS: Paired t-tests compared ADC, relative CBV, and DWI signals. RMSE and MAE were compared using repeated-measures analysis of variance. Significance was set at p < 0.05. RESULTS: ADC (p = 0.955-0.979) and CBV (p = 0.341-0.708), CBF (p = 0.684-0.983), and MTT (p = 0.403-0.971) values showed no significant differences between original and DLR images, while high-level DLR showed significantly higher TTP than original images. RCs demonstrated high reproducibility across DLR levels for ADC (21.78-22.20), CBV (0.88-0.96), CBF (27.98-34.18), MTT (1.26-1.50), and TTP (3.40-3.99). DSC analysis showed the best noise reduction with high-level DLR (lowest RMSE, 254.62 and MAE, 253.18 of DSC) without compromising CBV quantification. DATA CONCLUSION: DLR effectively reduced noise in DWI and DSC while preserving quantitative accuracy of ADC, CBV, CBF, and MTT. DLR may enable robust physiological MRI when applied in brain tumor imaging. TECHNICAL EFFICACY: Stage 3.
Whole-body magnetic resonance imaging (WB-MRI) has attracted attention recently for multi-organ assessment. Although there is a body of literature on diagnostic performance as well as recommendations for use in particula...Whole-body magnetic resonance imaging (WB-MRI) has attracted attention recently for multi-organ assessment. Although there is a body of literature on diagnostic performance as well as recommendations for use in particular high-risk subpopulations who require whole-body surveillance, WB-MRI has also entered the consumer market as a screening tool for average-risk individuals. For this latter purpose, there are proposed health-related benefits as well as controversies about the potential benefits and harms. The multi-disease screening of asymptomatic, average-risk groups with MRI, often with very low pre-test probability of clinically significant lesions or with limited detectability of disorders on imaging, signifies a major divergence from conventional screening principles. In some scenarios, it is plausible that WB-MRI improves disease detection and improves health outcomes, while lessening the inconvenience of multiple tests that each evaluate for a single-disease. However, the testing efficiency, clinical utility, and cost-effectiveness of large-scale implementation of screening WB-MRI are not established. In this narrative review, we highlight potential strengths and drawbacks based on the limited evidence to date. Awareness of the pathway for rigorous assessment of potential benefits and harms and current gaps in evidence may better guide research and inform implementation as interest in screening WB-MRI evolves. LEVEL OF EVIDENCE: 5. TECHNICAL EFFICACY: Stage 2.
BACKGROUND: 10%-30% of patients with lung adenocarcinoma (LUAD) and leptomeningeal metastasis (LM) respond poorly to conventional and targeted therapy. The relationship between genetic subtypes and both MRI features and...BACKGROUND: 10%-30% of patients with lung adenocarcinoma (LUAD) and leptomeningeal metastasis (LM) respond poorly to conventional and targeted therapy. The relationship between genetic subtypes and both MRI features and survival outcomes remains poorly understood in this patient population. PURPOSE: To explore the genetic phenotypes among LUAD-LM patients who respond poorly to conventional and targeted therapy, and to compare the MRI characteristics and survival outcomes among these genetic phenotypes: STUDY TYPE: Retrospective. POPULATION: 110 LUAD-LM patients (LU confirmed by histology, LM by cytology) treated with intrathecal chemotherapy, comprising 43 with epidermal growth factor receptor exon 21 L858R mutations (EGFR 21), 29 with EGFR exon 19 deletions (EGFR 19), and 38 with Non-Classic and Other Mutations (NCOM). FIELD STRENGTH/SEQUENCE: 3.0T; axial T - and T -weighted turbo spin echo (TSE), fluid-attenuated inversion recovery (FLAIR), diffusion-weighted echo-planar imaging (DWI), and post-contrast 3D T -weighted gradient-echo sequences (3D T1WI). ASSESSMENT: MRI morphologic features (including LM presence, presentation subtype, and lesion distribution) were independently reviewed by three radiologists (Y. J., W. S., and M. Y., with 5, 5, and 15 years of experience, respectively), following standardized criteria. Intracranial progression-free survival (iPFS) and overall survival (OS) were analyzed from the date of LM diagnosis based on clinical follow-up. STATISTICAL TESTS: Chi-square or Fisher's exact tests for imaging features; Kaplan-Meier method with log-rank tests for survival analysis; Cox proportional hazards regression for multivariable analysis. A two-sided p < 0.05 was considered significant. RESULTS: MRI-negative LM was significantly more frequent in EGFR 19 (65.5%). However, these patients showed no survival advantage (iPFS: p = 0.10, OS: p = 0.64) over other groups. Among MRI-positive LM patients, EGFR 21 affected significantly fewer lobes (< 4 lobes: 85.7%) compared to NCOM (< 4 lobes: 45.5%). Median iPFS in EGFR 21 was significantly longer than in NCOM (12.0 vs. 6.5 months; 95% CI: 5.16-7.84), and OS was also significantly longer (18.0 vs. 10.2 months; 95% CI: 4.79-15.61) DATA CONCLUSION: This radiogenomics study showed that EGFR mutation subtypes are associated with MRI features and survival outcomes in LUAD-LM patients with poor response to conventional and targeted therapies. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY STAGE: 4.