Radiologia Medica最新文献

Objectives: To investigate the use of intravoxel incoherent motion (IVIM) to study microperfusion and microstructural characteristics of lungs, brain, and placenta in normal and small fetuses.

Methods: We retrospectively enrolled 30 small fetuses and 82 normal pregnancies who underwent a 1.5-T MRI examination using an IVIM-DWI. Small fetuses were distinguished in small for gestational age (SGA) and "true" fetal growth restriction (FGR). ROIs were placed on the brain parenchyma, lungs, and fetal/maternal placental sides. Differences in perfusion fraction f, diffusion coefficient D, and pseudo-diffusion coefficient D* and their correlation with gestational age (GA) and birth weight (BW) were investigated.

Results: LUNG: f showed significantly lower values (p = 2·10^-7) in small fetuses (SGA + FGR); f discriminates SGA and FGR from normal (p = 0.001; p = 1·10^-6). f increases with GA (p < 0.0001) in the control group; a positive correlation was also obtained in small fetuses, although less significant.

Placenta: FGR showed lower f values than normal ones, in both the fetal (p = 1.4·10^-7) and maternal side (p = 0.001); f discriminates between SGA and FGR (p = 0.03). In small fetuses (SGA + FGR), f correlates positively with BW.

Brain: D values in supratentorial white matter (WM) were significantly higher compared to other regions, in both normal and small fetuses. Small fetuses showed higher D values in occipital WM and pons (p = 0.041; p = 0.027) than in normal. D correlates negatively with GA in the healthy group. No correlation between D and GA was found in SGA + FGR group.

Conclusions: In our study, IVIM-MRI allowed us to detect microstructural and microperfusion changes in the placenta, brain, and lung of small fetuses, noninvasively.

Purpose: This retrospective study aimed to evaluate the relationship between BPE on CEM and breast density, age and menopausal status.

Material and methods: Our analysis included all women eligible for CEM as a second-level examination in the diagnostic phase in a 12-month period. CEM were performed on a dedicated low-dose digital mammography unit after the injection of 1.5 ml/kg body weight Iohexol 350 mgI/ml. Both breast composition and BPE were assessed independently by two breast radiologists according to the CEM supplement to the 2013 ACR BI-RADS Mammography. A two-stage ordered probit regression model was fitted to evaluate the relationship between BPE and the other factors considered.

Results: 49 patients were included (median age = 55 years, 28.6% premenopausal and 71.4% postmenopausal). Breast composition was classified as ACR BI-RADS a in 4.1%, ACR BI-RADS b in 36.7%, ACR BI-RADS c in 46.9%, and ACR BI-RADS d in 12.2% of cases, by both Readers. A BPE 1 category was assigned in 53.1-55.1% of patients (by Reader 1 and 2, respectively), BPE 2 in 22.4%, BPE 3 in 18.4-12.2%, and BPE 4 in 6.1-10.2%. Higher breast density was strongly associated with higher levels of BPE, while BPE was not directly associated with age, both in fertile and postmenopausal patients. No significant differences were observed between the two Readers.

Conclusion: Increased BPE is associated with a well-established breast cancer risk factor as high breast density, while it was not directly dependent on the other non-modifiable factors considered.

Purpose: Ablation is a promising approach for eliminating intrathoracic metastases. We compared the effectiveness of a combination of metastasis-directed ablation and systemic therapy with that of systemic therapy alone for patients with hepatocellular carcinoma (HCC) having pulmonary oligometastases.

Materials and methods: We analyzed 679 patients with HCC and pulmonary oligometastases from seven tertiary hospitals. A total of 372 patients received systemic therapy (System group), whereas 307 patients received the combination therapy of pulmonary oligometastases ablation and systemic therapy (Ablation + System group).

Results: The median progression-free survival (PFS) was 9.7 ± 0.6 and 11.5 ± 0.6 months in the System and Ablation + System groups, respectively. The Ablation + System group exhibited significantly better PFS (hazard ratio [HR], 0.71; 95% confidence interval [CI] 0.60-0.85; P < 0.001) and overall survival (OS) (HR, 0.65; 95% CI 0.52-0.81; P < 0.001) than the System group. The subgroup analysis revealed that OS (HR, 0.91; 95% CI 0.65-1.28; P = 0.590) and PFS (HR, 0.81; 95% CI 0.62-1.05; P = 0.100) did not differ between tyrosine kinase inhibitor (TKI) and TKI plus programmed cell death protein-1 (PD-1) inhibitor therapies in the Ablation + system group. In addition, PFS (HR, 0.53; 95% CI 0.38-0.74; P < 0.001) and OS (HR, 0.66; 95% CI 52-0.84; P < 0.001) showed obviously different for intrahepatic tumors with partial response (PR) status.

Conclusion: The application of a combination of ablation of pulmonary oligometastases and systemic therapy resulted in longer PFS and OS than systemic therapy alone.

Purpose: Arterial spin labeling (ASL), a noninvasive magnetic resonance (MRI) perfusion sequence, holds promise in the presurgical evaluation of pediatric lesional epilepsy patients, including those with low-grade epilepsy-associated tumors (LEATs). The interpretation of ASL-derived perfusion patterns, however, presents challenges. Our study aims to elucidate these perfusion changes in children with LEATs, exploring their correlations with clinical, electroencephalography (EEG), and anatomical MRI findings.

Material and methods: Our cohort included 15 children with LEAT-associated focal lesional epilepsy who underwent single-delay pseudo-continuous ASL imaging; eight were imaged under sedation. We assessed perfusion images both qualitatively and quantitatively, focusing on LEAT-related perfusion changes, as indicated by the asymmetry index (AI) and regional cerebral blood flow (rCBF).

Results: ASL revealed LEAT-related perfusion changes in all but two patients: 12 LEATs were hypoperfused and one was hyperperfused relative to the contralateral brain parenchyma (CBP). LEATs showed significantly lower perfusion compared to CBP (median: 38.7 vs. 59.1 mL/100 g/min for LEAT and CBP, respectively; p value = 0.004, Wilcoxon-Mann-Whitney), regardless of sedation. Notably, elevated AI and rCBF values correlated with interictal spikes on EEG (median: -0.008 and 0.84 vs -0.27 and 0.58, respectively), but not to other clinical, EEG, or MRI variables (p value = 0.036, Wilcoxon-Mann-Whitney).

Conclusions: By highlighting the connection between LEAT and brain perfusion, and by correlating perfusion characteristics and epileptogenicity, our research enhanced our understanding of pediatric epilepsy associated with LEATs. Also, by proving the robustness of these findings to sedation we confirmed the importance of adding ASL to epilepsy protocols to as a valuable tool to supplement anatomical imaging.

Hearing loss is the most common sensory impairment globally and can affect all ages. It can be classified into two categories, conductive and sensorineural, though both conditions may coexist. Various causes may be responsible for hearing loss including congenital, infectious, inflammatory and neoplastic. Imaging will help detect or exclude such causes and in combination with the medical history and clinical findings, enable the necessary treatment to be initiated. Imaging also provides an accurate pre-operative anatomical road map for the surgeons to ensure the best possible surgical outcomes. The aim of this educational review is to present a range of common and rare diseases causing hearing loss and provide a brief explanation of the best imaging modalities for each. It also discusses briefly some important anatomical variants which the radiologists should highlight in their report to help prevent inadvertent post-operative complications.

Background and purposes: Non-invasive optimal vessel analysis quantitative magnetic resonance angiography (NOVA-QMRA) has emerged as a valuable tool to characterize cerebral hemodynamics in intracranial atherosclerotic disease (ICAD). Our aim was to explore the eventual correlation between volume flow rate (VFR) measured via NOVA-QMRA and signal intensity ratio (SIR) of time-of-flight (TOF) MRA in M1- and P2-segments bilaterally in patients with unilateral internal carotid artery (ICA) occlusion.

Materials and methods: Patients with acute, subacute or chronic unilaterall ICA occlusion receiving NOVA-QMRA between June 2019 and June 2021 were retrospectively included. In bilateral M1- and P2-segments VFR was assessed by means of NOVA-QMRA and a region of interest (ROI) was selected to measure TOF SIR. A correlation between TOF SIR and VFR was tested by means of Pearson correlation coefficient. Mean difference of TOF SIR and VFR between ipsilateral (to occluded ICA) and contralateral M1- and P2-segments was analyzed using a two-sided Welch's t test.

Results: Fifty-five patients with unilateral ICA occlusion were included (acute: 28; subacute: 8; chronic: 19). Both ipsilateral (r = 0.536, p < 0.001) and contralateral (r = 0.757, p < 0.001) TOF SIR correlated significantly with NOVA VFR. This observation proved especially true for patients with chronic ICA occlusion. Both VFR (165.18 vs 110.60, p < 0.001) and TOF SIR (4.96 vs 2.70, p < 0.001) were higher in contralateral than ipsilateral M1-segments; whereas, the contrary was observed for P2-segments (VFR 72.35 vs 102.12, p < 0.001, TOF SIR 2.87 vs 3.39, p = 0.016).

Conclusion: The study results showed that TOF SIR significantly correlated with phase-contrast derived flow volume in patients with symptomatic ICA occlusion. This correlation remains the same regardless of the stage of the ischemic stroke (acute vs subacute vs chronic). Furthermore, significantly high VFR and TOF SIR in ipsilateral P2-segments may provide evidence of leptomeningeal collateralization in acute patients. Standardly performed TOF SIR Sequences might be of help for a qualitative evaluation of the flow in M1- and P2-segments in patients with unilateral ICA occlusions. NOVA QMRA allows precise quantitative measurements of the flow in cerebral vessels.

Purpose: To evaluate the ability of magnetic resonance imaging (MRI)-based clustering analysis to predict the pathological response to neoadjuvant chemotherapy (NACT) in patients with primary high-grade osteosarcoma.

Materials and methods: Twenty-two patients were included in this retrospective study. All patients underwent MRIs before and after NACT. The entire tumor volume was manually delineated on post-contrast T1-weighted images and subsegmented into three clusters using the K-means algorithm. Histogram-based parameters were calculated for each lesion. The response to NACT was obtained from the histopathological assessment of the tumor necrosis rate following resection. The Mann-Whitney test was used to compare poor and fair-to-good responders. The receiver operating characteristic curve was used to evaluate the diagnostic performance of the optimal parameters.

Results: At baseline, poor responders showed a significantly larger volume of cluster1 (Vol1) than fair-to-good responders (p = 0.038). After NACT, they exhibited a lower 10th percentile (P10) and kurtosis (p = 0.038 and 0.002, respectively). Vol1 at baseline and P10 after NACT had an AUC of 77% (95% CI 56-98%). The kurtosis after NACT had the best discriminative power, with an AUC of 89.7% (95% CI 75-100%).

Conclusion: The MRI-based histogram and clustering analysis provided a good ability to differentiate between poor and fair-to-good responders before and after NACT. Further investigations using larger datasets are required to corroborate our findings.

Background: Prostate cancer ranks as the second most common cancer in men worldwide. Dose escalation to the tumor and/or the prostate improves biochemical recurrence-free survival. However, interobserver variability in lesion contouring poses a significant limitation to such therapeutic approaches. Therefore, a study of factors influencing this variability is necessary.

Materials and methods: Three independent readers delineated the index prostate lesion (DIL) using T2w and ADC sequences for each patient. Clinical data were retrospectively collected for all participants. Logistic regression analysis was employed to examine the correlation between clinical features and a mean DICE coefficient > 0.7. Features exhibiting a p value < 0.05 on univariate analysis were subjected to multivariate analysis.

Results: The study comprised 68 patients, with a median DICE coefficient of 0.69 (95% CI 0.65-0.71), wherein 42.6% (29/68) attained a mean DICE > 0.7. Univariate analysis identified the PI-QUAL score, maximum diameter of DIL, and mean DIL volume as significant (p < 0.05) predictors. In multivariate analysis, only the PI-QUAL score (p = 0.008) remained statistically associated with a DICE coefficient > 0.7.

Conclusion: The PI-QUAL score emerges as the primary predictive factor for minimizing inter-reader variability in intraprostatic dominant lesion segmentation. These findings underscore the importance of considering PI-QUAL scores when devising focal treatment plans. Adoption of a multi-reader approach involving diverse medical specialists (radiologists, radiotherapists, urologists) is advocated, particularly for MRIs with low PI-QUAL scores.

Clinical relevance statement: Radiotherapy is a major treatment for patients with localized prostate cancer. Dose escalation to the tumor leads to improved cancer control. Precise delineation of the dominant intraprostatic lesion (DIL) remains a limitation to focal treatments. Features influencing inter-reader variability were never evaluated. In this study, we identified that the PI-QUAL score was the sole predictor of the inter-reader delineation variability of the DIL.

Purpose: To evaluate the differences in efficacy and safety between the 100 and 150 W percutaneous microwave ablation (MWA) systems in the treatment of hepatocellular carcinoma (HCC).

Methods: We retrospectively reviewed all patients who underwent percutaneous MWA (Emprint™ HP Ablation System, Medtronic) between January 2021 and May 2023. We divided the cohort into two groups: Group 1, treated with MWA at 100 W power system, and Group 2, treated with 150 W one. Effectiveness was defined as the absence of residual disease at 1-month CT follow-up; safety was defined as the absence of grade II-VI complications.

Results: A total of 135 HCC nodules were treated with MWA in 87 patients with a median age of 66 ± 10 years: 76 procedures in 42 patients were carried out in group 1, while 59 procedures in 45 patients in group 2. Cases treated with 150 W had a shorter ablation time (p: 0.002; mean 227.37 ± 92.5 vs 180.51 ± 75.6 s (100 vs 150 W)) and a larger ablation volume (p 0.008; mean 13,920.0 ± 10,723.2 vs 21,241.4 ± 18,374.7 mm³ (100 vs 150 W)), and a major effectiveness at 1-month CT follow-up (p: 0.013). A higher rate of complications (grade II and III) was observed in Group 2 (p < 0.001).

Conclusions: In conclusion, these preliminary results showed a good correlation between intended-to-treat area and ablation volume and intended-to-treat area and ablation time for both Groups. A minor ablation time, and major ablation volume, but also a higher incidence of complications was observed in 150 W Group.

Objective: This study evaluates the diagnostic criteria of MRI for breast implant rupture and examines the influence of radiologist experience on the accuracy of rupture detection.

Methods: A retrospective study was conducted in a single center, involving patients who underwent implant replacement surgery between March 2019 and October 2022. MRI evaluations by four radiologists of varying experience levels were compared with surgical outcomes.

Results: The study included 118 explanted prostheses, with 25 identified as ruptured. Expert radiologists demonstrated near-perfect agreement (κ = 0.94) in identifying rupture signs, with high PPV and NPV, whereas non-experts showed only moderate agreement (κ = 0.44). Indicators such as the linguine sign, subcapsular line, and keyhole sign were identified with high accuracy by experts, contrasting with non-experts' lower detection rates.

Conclusions: Expertise in radiology significantly impacts the accurate diagnosis of breast implant ruptures. This study supports updating radiological guidelines and underscores the importance of specialized training and experience in improving diagnostic outcomes in breast implant assessments.