Yoshiyuki Ozawa

Management of lung cancer (LC) encompasses screening, diagnosis, staging, radiotherapy planning and guidance, therapy monitoring and surveillance. Across these domains, magnetic resonance imaging (MRI) offers a range of morphological and functional imaging capabilities-including diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) imaging, and whole-body MRI-to complement established imaging modalities. Recent technical advances have substantially improved the feasibility of lung MRI, enabling more reliable image acquisition and lesion assessment under controlled conditions. In LC screening, meta-analyses and prospective studies indicate that MRI can detect solid pulmonary nodules above clinically actionable size thresholds with moderate to high sensitivity and a low false-positive rate. However, the available evidence is largely derived from pilot studies, selected cohorts, and modeling-based analyses. MRI should therefore be regarded as technically feasible for screening but not yet a validated alternative to low-dose computed tomography in population-based programs. For staging, whole-body MRI incorporating DWI has demonstrated comparable diagnostic performance to standard multimodality pathways in prospective and randomized studies, with potential advantages including reduced radiation exposure and streamlined imaging workflows. In radiotherapy planning, DCE, DWI, and motion-resolved MRI techniques can improve target delineation and treatment adaptation, but their use remains largely confined to specialized centers. MRI shows promise for therapy response assessment and prognostication through quantitative DCE- and DWI-derived biomarkers, although reported parameters remain heterogeneous and insufficiently standardized for routine clinical decision-making. Overall, MRI has established clinical utility in selected aspects of LC management, while broader adoption is currently limited by availability, standardization, and validation gaps. Further technical refinement and large-scale prospective trials are required to define its role in routine clinical practice. LEVEL OF EVIDENCE: 5. TECHNICAL EFFICACY: Stage 2.

BACKGROUND: We compared the capabilities of quantitatively assessed paired inspiratory-expiratory area-detector computed tomography (ADCT) for pulmonary functional loss and disease severity evaluations between upright and supine ADCT in matched progressive pulmonary fibrosis (PPF) patients. MATERIALS AND METHODS: This retrospective cohort consisted of age-, sex-, and underlying disease-matched patients with PPF who underwent paired inspiratory-expiratory CT on upright ADCT (n = 40) and supine ADCT (n = 40), pulmonary function tests, and disease severity assessment. Based on CT data, the absolute values of the logarithm of the Jacobian determinant and warp-field magnitude of the whole lung and all lobes were calculated. Stepwise regression analyses were performed. RESULTS: On supine ADCT, both indices of the left lower lobe (LLL) were the first and only steps for pulmonary function test results and CT-assessed disease severity (absolute value of the logarithm of the Jacobian determinant: 0.139 ≤ r2 ≤ 0.175, 0.007 ≤ p ≤ 0.018; absolute value of the warp-field magnitude: 0.371 ≤ r2 ≤ 0.447, p < 0.001). However, on upright ADCT, both indices indicated that LLL was the first step and the right lower lobe was the second step for pulmonary function test results and CT-assessed disease severity (0.503 ≤ r2 ≤ 0.674, p < 0.001 or 0.000 < p ≤ 0.006 and 0.474 ≤ r2 ≤ 0.652, 0.002 ≤ p ≤ 0.045, respectively). CONCLUSION: Upright ADCT has equal to or better potential than supine ADCT for detecting pulmonary functional loss and evaluating disease severity when paired inspiratory-expiratory ADCT is applied in PPF patients. RELEVANCE STATEMENT: Upright ADCT has superior potential to supine ADCT for pulmonary functional loss and disease severity evaluations when paired inspiratory-expiratory ADCT is performed in patients with progressive pulmonary fibrosis (PPF). KEY POINTS: Matched progressive pulmonary fibrosis patients compared functional loss and disease severity evaluations between inspiratory-expiratory upright and supine area-detector CT. Clinical parameters demonstrated better correlations with upright than with supine inspiratory-expiratory area-detector CT. Warp-field magnitude showed better correlations with disease severities than the logarithm of the Jacobian determinant on each area-detector CT.

PURPOSE: The purpose of this study was to directly compare diagnostic capability of inguinal herniation between upright area-detector CT (ADCT) and conventional supine ADCT under the Valsalva maneuver. MATERIALS AND METHODS: This retrospective study included 209 patients with 360 inguinal herniations and 123 patients without inguinal hernias. All patients underwent supine and upright ADCT for the evaluation of abdominal wall hernias within one week between May 2023 and March 2024. From this cohort, a total of 120 of 360 inguinal hernias and 120 of 304 non-inguinal hernias were computationally selected, and the probability of hernia was visually assessed by two board-certified general and abdominal radiologists with 5-point scales to assess subtypes of herniation. The final score for each hernia was determined as consensus of two investigators. To determine the capability of diagnosis for inguinal herniation in selected lesion groups, diagnostic performance was compared between upright and supine ADCTs using an ROC analysis. Then, sensitivity (SE), specificity (SP), and accuracy (AC) for differentiation of inguinal from non-inguinal hernias were compared between the two methods using McNemar's test. RESULTS: The area under the curve (AUC) of upright ADCT (AUC = 0.96) was significantly larger than that of supine ADCT (AUC = 0.93, p < 0.0001). Sensitivity (SE) and accuracy (AC) of upright ADCT (SE: 87.5 %, AC: 93.8 %) were significantly higher than those of supine ADCT (SE: 73.3 %, p < 0.0001; AC: 86.7 %, p < 0.0001). CONCLUSION: Upright ADCT has better potential for the diagnosis and subtype classification of inguinal herniation than conventional supine ADCT when applied under the Valsalva maneuver.

Background/Objectives: The rates and predictors of clinical remission, a novel and practical therapeutic goal in severe asthma, have been inconsistently reported across studies. Data on clinical remission in Japanese patients remain limited. The aim of this study was to assess the rate of four-component clinical remission and its predictors in Japanese adult patients with severe asthma. Methods: This retrospective study enrolled adult patients with severe asthma who had initiated biologic therapy at least 12 months prior to inclusion at Nagoya City University Hospital. The primary endpoint was the achievement rate of four-component clinical remission, defined as (1) no maintenance oral corticosteroids (OCS); (2) no exacerbations for 12 months; (3) Asthma Control Test (ACT) score ≥ 20; and (4) forced expiratory volume in one second (FEV1) ≥ 80% of predicted. The secondary endpoint was to identify factors, including airway structural indices measured using chest computed tomography (CT), associated with clinical remission at 12 months. Results: Among 87 patients with severe asthma, 26 (30%) achieved four-component clinical remission after 12 months of biologic therapy. In univariate analysis, clinical remission was more frequently achieved in patients with chronic rhinosinusitis, higher FEV1 (% predicted), higher blood eosinophil counts, higher ACT scores, fewer exacerbations in the previous year, higher Lund–Mackay scores, and smaller airway wall thickness and luminal areas on CT (all p &lt; 0.05). Multivariate analysis revealed that higher blood eosinophil counts and fewer exacerbations in the previous year were independently associated with clinical remission (both p &lt; 0.05). Conclusions: After 12 months of biologic therapy, 30% of patients with severe asthma achieved four-component clinical remission. Higher blood eosinophil counts and fewer prior exacerbations were associated with higher remission rates.