High dose proton and photon-based radiation therapy for 213 liver lesions: a multi-institutional dosimetric comparison with a clinical perspective.

BACKGROUND: Stereotactic radiotherapy (SRT) and Proton therapy (PT) are both options in the management of liver lesions. Limited clinical-dosimetric comparison are available. Moreover, dose-constraint routinely used in liver PT and SRT considers only the liver spared, while optimization strategies to limit the liver damaged are poorly reported. METHODS: Primary endpoint was to assess and compare liver sparing of four contemporary RT techniques. Secondary endpoints were freedom from local recurrence (FFLR), overall survival (OS), acute and late toxicity. We hypothesize that Focal Liver Reaction (FLR) is determined by a similar biologic dose. FLR was delineated on follow-up MRI. Mean C.I. was computed for all the schedules used. A so-called Fall-off Volume (FOV) was defined as the area of healthy liver (liver-PTV) receiving more than the isotoxic dose. Fall-off Volume Ratio (FOVR) was defined as ratio between FOV and PTV. RESULTS: 213 lesions were identified. Mean best fitting isodose (isotoxic doses) for FLR were 18Gy, 21.5 Gy and 28.5 Gy for 3, 5 and 15 fractions. Among photons, an advantage in terms of healthy liver sparing was found for Vmat FFF with 5mm jaws (p = 0.013) and Cyberknife (p = 0.03). FOV and FOVR resulted lower for PT (p < 0.001). Three years FFLR resulted 83%. Classic Radiation induced liver disease (RILD, any grade) affected 2 patients. CONCLUSIONS: Cyberknife and V-MAT FFF with 5mm jaws spare more liver than V-MAT FF with 10 mm jaws. PT spare more liver compared to photons. FOV and FOVR allows a quantitative analysis of healthy tissue sparing performance showing also the quality of plan in terms of dose fall-off.

MRI of Peliosis Hepatis: A Case Series Presentation With a 2022 Systematic Literature Update.

BACKGROUND: Peliosis hepatis (PH) is a rare benign condition, characterized by hepatic sinusoidal dilatation and blood-filled cystic cavities, often found incidentally, with still challenging diagnosis by imaging due to polymorphic appearance. PURPOSE: Based on a retrospective analysis of our series (12 patients) and systematic literature review (1990-2022), to organize data about PH and identify features to improve characterization. STUDY TYPE: Retrospective case series and systematic review. POPULATION: Twelve patients (mean age 48 years, 55% female) with pathology-proven PH and 49 patients (mean age 52 years, 67% female) identified in 33 studies from the literature (1990-2022). FIELD STRENGTH/SEQUENCE: 1,5-T; T1-weighted (T1W), T2-weighted (T2W), diffusion-weighted (DW), contrast-enhanced (CE) T1W imaging. ASSESSMENT: We compared our series and literature data in terms of demographic (gender/age/ethnicity), clinical characteristics (symptoms/physical examination/liver test), associated conditions (malignancies/infectious/hematologic/genetic or chronic disorders/drugs or toxic exposure) percentage. On magnetic resonance imaging lesion numbers/shape/mean maximum diameter/location/mass effect/signal intensity were compared. PH pathological type/proposed imaging diagnosis/patient follow-up were also considered. STATISTICAL TESTS: Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Case Reports/Series quality assessment. Intraclass correlation and Cohen's kappa coefficients for levels of inter/intrareader agreement in our experience. RESULTS: Patients were mainly asymptomatic (92% vs. 70% in our study and literature) with associated conditions (83% vs. 80%). Lesions showed homogeneous T1W-hypointensity (58% vs. 65%) and T2W-hyperintensity (58% vs. 66%). Heterogeneous nonspecific (25% vs. 51%), centrifugal (34% vs. 8%), or rim-like centripetal (25% vs. 23%) patterns of enhancement were most frequent, with hypointensity on the hepatobiliary phase (HBP), without restricted diffusivity. Good inter- and intrareader agreement was observed in our experience. Concerning JBI Checklist, 19 out of 31 case reports met at least 7 out of 8 criteria, whereas 2 case series fulfilled 5 and 6 out of 10 items respectively. DATA CONCLUSION: A homogeneous, not well-demarcated T1W-hypointense and T2W-hyperintense mass, with heterogeneous nonspecific or rim-like centripetal or centrifugal pattern of enhancement, and hypointensity on HBP, may be helpful for PH diagnosis. Among associated conditions, malignancies and drug exposures were the most frequent. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 2.

Comparison of Gadobenate-Enhanced MRI and Gadoxetate-Enhanced MRI for Hepatocellular Carcinoma Detection Using LI-RADS Version 2018: A Prospective Intraindividual Randomized Study.

BACKGROUND. Gadobenate and gadoxetate show different degrees of intracellular accumulation within hepatocytes, potentially impacting these agents' relative performance for hepatocellular carcinoma (HCC) diagnosis. OBJECTIVE. The purpose of this article was to perform an intraindividual comparison of gadobenate-enhanced MRI and gadoxetate-enhanced MRI for detection of HCC and to assess the impact of inclusion of hepatobiliary phase images on HCC detection for both agents. METHODS. This prospective study enrolled 126 patients (112 men, 14 women; mean age, 52.3 years) at high risk for HCC who consented to undergo two 3-T liver MRI examinations (one using gadobenate [0.05 mmol/kg], one using gadoxetate [0.025 mmol/kg]) separated by 7-14 days. The order of the two contrast agents was randomized. All examinations included postcontrast dynamic and hepatobiliary phase images (120 minutes for gadobenate, 20 minutes for gadoxetate). Three radiologists independently reviewed the gadobenate and gadoxetate examinations in separate sessions and recorded the location of detected observations. Observations were classified using LI-RADS version 2018 and using a LI-RADS modification whereby hepatobiliary phase hypointensity may upgrade observations from category LR-4 to LR-5. Observations classified as LR-5 were considered positive interpretations for HCC. Diagnostic performance for histologically confirmed HCC (n = 96) was assessed. RESULTS. Across readers, sensitivity for HCC for gadobenate versus gadoxetate was 74.0-80.2% versus 54.2-67.7% using dynamic images alone and 82.1-87.4% versus 66.3-81.1% using dynamic and hepatobiliary phase images. For HCCs measuring 1.0-2.0 cm, sensitivity for gadobenate versus gadoxetate was 61.9% (all readers) versus 38.1-57.1% using dynamic images alone and 76.2-85.7% versus 52.4-61.9% using dynamic and hepatobiliary phase images. PPV for HCC ranged from 88.6% to 97.4% across readers, agents, and image sets. CONCLUSION. Sensitivity for HCC was higher for gadobenate than for gadoxetate, whether using dynamic images alone or dynamic and hepatobiliary phase images; the improved sensitivity using gadobenate was more pronounced for small HCCs. Whereas hepatobiliary phase images improved sensitivity for both agents, sensitivity of gadobenate using dynamic images alone compared favorably with that of gadoxetate using dynamic and hepatobiliary phase images. CLINICAL IMPACT. The findings support gadobenate as a preferred agent over gadoxetate when performing liver MRI in patients at high risk for HCC.

Ultrasound and magnetic resonance imaging in the diagnosis of clinically significant placenta accreta spectrum disorders.

OBJECTIVES: We aimed to assess the performance of ultrasound (US) and magnetic resonance imaging (MRI) signs for antenatal detection of placenta accreta spectrum (PAS) disorders in women with placenta previa (placental edge ≤2 cm from the internal uterine orifice, ≥260/7 weeks' gestation) with and without a history of previous Caesarean section. METHODS: Single center prospective observational study. US suspicion of PAS was raised in the presence of obliteration of the hypoechoic space between uterus and placenta, interruption of the hyperechoic uterine-bladder interface and/or turbulent placental lacunae on color Doppler. All MRI studies were blindly evaluated by a single operator. PAS was defined as clinically significant when histopathological diagnosis was associated with at least one of: intrauterine balloon placement, compressive uterine sutures, peripartum hysterectomy, uterine or hypogastric artery ligature, uterine artery embolization. RESULTS: A total of 39 women were included: 7/39 had clinically significant PAS. There were 6/18 cases of PAS with anterior placenta: hypoechoic space interruption and placental lacunae were the most sensitive sonographic signs (83%), while abnormal hyperechoic interface was the most specific (83%). On MRI, focal myometrial interruption and T2 intraplacental dark bands showed the best sensitivity (83%), bladder tenting had the best specificity (100%). 1/21 women with posterior placenta had PAS. There was substantial agreement between US and MRI in patients with anterior placenta (κ=0.78). CONCLUSIONS: US and MRI agreement in antenatal diagnosis of clinically significant PAS was maximal in high-risk women. Placental lacunae on ultrasound scan and T2 intraplacental hypointense bands on MRI should trigger the suspicion of PAS.

Whole-body magnetic resonance imaging (WB-MRI) for cancer screening: recommendations for use.

Whole-body magnetic resonance imaging (WB-MRI) is currently recommended for cancer screening in adult and paediatric subjects with cancer predisposition syndromes, representing a substantial aid for prolonging health and survival of these subjects with a high oncological risk. Additionally, the number of studies exploring the use of WB-MRI for cancer screening in asymptomatic subjects from the general population is growing. The primary aim of this review was to analyse the acquisition protocols found in the literature, in order to identify common sequences across published studies and to discuss the need of additional ones for specific populations. The secondary aim of this review was to provide a synthesis of current recommendations regarding the use of WB-MRI for cancer screening.

Consensus report from the 8th International Forum for Liver Magnetic Resonance Imaging.

OBJECTIVES: The 8th International Forum for Liver Magnetic Resonance Imaging (MRI), held in Basel, Switzerland, in October 2017, brought together clinical and academic radiologists from around the world to discuss developments in and reach consensus on key issues in the field of gadoxetic acid-enhanced liver MRI since the previous Forum held in 2013. METHODS: Two main themes in liver MRI were considered in detail at the Forum: the use of gadoxetic acid for contrast-enhanced MRI in patients with liver cirrhosis and the technical performance of gadoxetic acid-enhanced liver MRI, both opportunities and challenges. This article summarises the expert presentations and the delegate voting on consensus statements discussed at the Forum. RESULTS AND CONCLUSIONS: It was concluded that gadoxetic acid-enhanced MRI has higher sensitivity for the diagnosis of hepatocellular carcinoma (HCC), when compared with multidetector CT, by utilising features of hyperenhancement in the arterial phase and hypointensity in the hepatobiliary phase (HBP). Recent HCC management guidelines recognise an increasing role for gadoxetic acid-enhanced MRI in early diagnosis and monitoring post-resection. Additional research is needed to define the role of HBP in predicting microvascular invasion, to better define washout during the transitional phase in gadoxetic acid-enhanced MRI for HCC diagnosis, and to reduce the artefacts encountered in the arterial phase. Technical developments are being directed to shortening the MRI protocol for reducing time and patient discomfort and toward utilising faster imaging and non-Cartesian free-breathing approaches that have the potential to improve multiphasic dynamic imaging. KEY POINTS: • Gadoxetic acid-enhanced MRI provides higher diagnostic sensitivity than CT for diagnosing HCC. • Gadoxetic acid-enhanced MRI has roles in early-HCC diagnosis and monitoring post-resection response. • Faster imaging and free-breathing approaches have potential to improve multiphasic dynamic imaging.

Characterization of the arterial enhancement pattern of focal liver lesions by multiple arterial phase magnetic resonance imaging: comparison between hepatocellular carcinoma and focal nodular hyperplasia.

PURPOSE: To evaluate the features of arterial enhancement pattern of focal nodular hyperplasia (FNH) and hepatocellular carcinoma (HCC) by triple-phase arterial magnetic resonance imaging (MRI). METHODS: Data were retrospectively collected from 52 consecutive patients who underwent triple-phase arterial MRI using hepatocyte-specific contrast agents (Gd-EOB-DTPA) from January 2017 to October 2017, with a MR imaging diagnosis of HCC or FNH. The images were independently assessed by two blinded readers. Contrast enhancement ratio (CER) and liver-to-lesion contrast ratio (LLCR) were calculated. The lesions were classified visually and also based on the peak of LLCR into the following groups: (1) early arterial, (2) middle arterial and (3) late arterial. Data were eventually analysed using nonparametric tests. RESULTS: The CER analysis showed no significant difference between HCC and FNH patients (p > 0.05). LLCRFNH were significantly higher than LLCRHCC in the early arterial (p = 0.01), but not in the middle and late arterial phases (p = 0.20 and p = 0.82, respectively). LLCRHCC presented a meaningful increase from early to middle arterial phase (p = 0.009), whereas LLCRFNH showed a decrease from middle to late arterial phase (p = 0.004). Based on the peak of LLCR, 17 (55%) FNHs were classified into early, 11 (35%) in middle and only 3 (10%) in late arterial phase groups. Similarly, 14 (34%) HCCs were categorized into early, 13 (32%) in middle and 14 (33%) in late arterial phase groups. There was a good agreement between qualitative analysis and LLCR in 85% of cases. CONCLUSION: The optimal visualization of FNH has been detected in early and middle arterial phases while HCC has been best observed during middle and late arterial phases.

Detection of liver metastases on gadobenate dimeglumine-enhanced MRI: systematic review, meta-analysis, and similarities with gadoxetate-enhanced MRI.

OBJECTIVES: To determine the sensitivity and positive predictive value (PPV) of gadobenate-enhanced MR imaging for the detection of liver metastases. METHODS: This systematic review and meta-analysis was conducted according to PRISMA guidelines. A comprehensive search (EMBASE, PubMed) was performed to identify relevant articles up to December 2017. Studies eligible for inclusion were performed using appropriate methodology with complete verification by means of histopathology, intraoperative observation and/or follow-up, and sufficient information to permit determination of true-positive (TP), false-negative (FN), and false-positive (FP) values. Sources of bias were assessed using the QUADAS-2 tool. An inverse variance-weighted random-effects model was used to obtain sensitivity and PPV estimates. Information was analyzed and presented using Cochran's Q statistic, funnel plots, and modified Deeks' analysis. RESULTS: Ten articles (256 patients, 562 metastases) were included. Sensitivity estimates for pre-contrast (unenhanced) imaging, gadobenate-enhanced dynamic imaging, and combined unenhanced, dynamic, and delayed hepatobiliary phase imaging for detecting liver metastases on a per-lesion basis were 77.8% (95% CI 71.4-84.3%, 7 assessments), 88.1% (95% CI, 84.0-92.2%, 13 assessments), and 95.1% (95% CI 93.1-97.1%, 15 assessments), respectively. The addition of hepatobiliary phase images significantly improved the detection of liver metastases. The overall PPV was 90.9% (95% CI 86.6-95.1%, 11 assessments). Deeks' funnel analysis revealed no association between sample size and sensitivity (ß = 0.02, p = 0.814) indicating no significant publication bias. CONCLUSIONS: Gadobenate-enhanced MR imaging has high sensitivity and PPV for the detection of liver metastases on a per-lesion basis. The sensitivity and PPV for detection is comparable to reported values for the pure liver-specific agent gadoxetate. KEY POINTS: • Gadobenate dimeglumine is a hepatobiliary MR contrast agent that permits acquisition of contrast-enhanced liver images during the immediate post-injection dynamic phase, like any extracellular agent, and in the delayed hepatobiliary phase, after specific uptake by the hepatocytes. • The hepatobiliary phase improves detection of liver metastases when compared either to pre-contrast unenhanced images alone or to pre-contrast + gadobenate-enhanced dynamic phase images. • The meta-analysis showed an overall sensitivity of 95.1% and PPV of 90.9% of gadobenate-enhanced MRI for the detection of metastases, when based on the evaluation of all available acquisitions.

Whole-body magnetic resonance imaging (WB-MRI) in oncology: recommendations and key uses.

The past decade has witnessed a growing role and increasing use of whole-body magnetic resonance imaging (WB-MRI). Driving these successes are developments in both hardware and software that have reduced overall examination times and significantly improved MR imaging quality. In addition, radiologists and clinicians have continued to find promising new applications of this innovative imaging technique that brings together morphologic and functional characterization of tissues. In oncology, the role of WB-MRI has expanded to the point of being recommended in international guidelines for the assessment of several cancer histotypes (multiple myeloma, melanoma, prostate cancer) and cancer-prone syndromes (Li-Fraumeni and hereditary paraganglioma-pheochromocytoma syndromes). The literature shows growing use of WB-MRI for the staging and follow-up of other cancer histotypes and cancer-related syndromes (including breast cancer, lymphoma, neurofibromatosis, and von Hippel-Lindau syndromes). The main aim of this review is to examine the current scientific evidence for the use of WB-MRI in oncology.

Focal Nodular Hyperplasia After Treatment With Oxaliplatin: A Multiinstitutional Series of Cases Diagnosed at MRI.

OBJECTIVE: Benign hepatic lesions may occur after chemotherapy treatment and may mimic metastases at imaging. We describe focal nodular hyperplasia (FNH) lesions diagnosed at MRI that occurred de novo after treatment with oxaliplatin. MATERIALS AND METHODS: This is a multiinstitutional case series. We report 14 adult patients with cancer (eight men and six women) with a history of treatment with oxaliplatin and development of new hepatic lesions diagnosed as FNH at pathologic analysis or MRI or both. Imaging and pathology features of the included lesions, the interval since chemotherapy, and the temporal evolution were reviewed. RESULTS: The mean interval between the completion of oxaliplatin treatment and the identification of new hepatic FNH at imaging was 47.6 months. In seven of 14 (50%) patients, the index lesion was diagnosed at pathologic analysis (biopsy or resection) as FNH. In the remaining seven cases, the diagnosis was based on highly accurate MRI features (e.g., hyper- or isointensity of the lesion on hepatobiliary phase images). Lesion growth or occurrence of new lesions was present in 75% of patients at imaging follow-up. CONCLUSION: FNH lesions can occur de novo after treatment with oxaliplatin. Recognizing the typical MRI appearance of these lesions may avoid unnecessary biopsy or surgery and reduce patients' anxiety.

Evaluation of incidence of acute transient dyspnea and related artifacts after administration of gadoxetate disodium: a prospective observational study.

AIMS: To evaluate motion artifacts, breath-hold failure, acute transient dyspnea, and clinical parameters during hepatic arterial phase of gadoxetate disodium-enhanced magnetic resonance (MR) imaging. METHODS: This was an institutional review board-approved observational prospective study (written informed consent acquired) performed in 250 consecutive patients, who underwent liver MR with a multiarterial phase technique. Oxygen saturation (SatO2) and heart rate (HR) were monitored, while patients reported subjective symptoms. Breath-holds were assessed using prospective acquisition correction technique (PACE) monitors. Three readers independently analyzed all images to establish the presence of motion artifacts. Nonparametric statistical testing and Fleiss' kappa were used. RESULTS: No statistical differences in SatO2 and HR values were observed during the entire length of MR examination. The PACE graphs showed an altered breath-hold in 16/250 patients (6.4%), however only 6 patients self-reported symptoms during the procedure, and among these 6 subjects, only 2 suffered from acute transient dyspnea (0.8%). Motion-related artifacts increased mostly in the third arterial phase of gadoxetate disodium acquisition (p < 0.0001): The artifacts incidence was 2.9% in the first phase; 4.0% in the second; and 19.5% in the third. This increase was mainly due to patients' inability to hold their breath for the entire duration of the examination. However, at least one gadoxetate disodium arterial phase without motion artifacts and adequate for acquisition timing, was acquired in all MR examinations. CONCLUSION: The incidence of breath-hold failure and acute transient dyspnea after gadoxetate disodium administration increased during the third arterial phase only. Our protocol allowed the acquisition of at least one arterial phase not compromised by motion artifacts and adequate for acquisition timing, in all patients.

Whole-Body MRI: Current Applications in Oncology.

OBJECTIVE: The purpose of this article is to review current image acquisition and interpretation for whole-body MRI, clinical applications, and the emerging roles in oncologic imaging, especially in the assessment of bone marrow diseases. CONCLUSION: Whole-body MRI is an emerging technique used for early diagnosis, staging, and assessment of therapeutic response in oncology. The improved accessibility and advances in technology, including widely available sequences (Dixon and DWI), have accelerated its deployment and acceptance in clinical practice.

MRI of hepatic epithelioid hemangioendothelioma (HEH).

PURPOSE: To investigate magnetic resonance imaging (MRI) characteristics of hepatic epithelioid hemangionendothelioma (HEH). MATERIALS AND METHODS: The study was exempted from formal Ethics Committee approval due to its retrospective and noninvasive nature. Eleven patients with histology-proven HEH were collected from six different institutions in a 5-year time period. In all patients a contrast-enhanced MR study was available. Two experienced reviewers in consensus retrospectively noted potential MR findings of HEH. Reviewers separately analyzed morphological findings, tumor signal intensity, HEH contrast enhancement pattern, and tumor appearance on hepatobiliary phase and diffusion-weighted imaging (DWI). The frequency of various findings was calculated. RESULTS: The most frequent presentation was a peripheral distribution of the lesions (72.7%), target appearance on T2-weighted images (63.6%), low signal intensity on T1-weighted images (63.6%), ring or target-like enhancement at dynamic study (63.6%), and coalescence of nodules and capsular retraction (45.4%). Lack of hepatobiliary enhancement (5/8 patients) or "entrapment" hepatobiliary enhancement (3/8 patients) as well as target appearance at DWI (5/6 patients) was also observed in our series. CONCLUSION: Although quite variable imaging appearances were seen, a target appearance on the T2-weighted image, ring or target enhancement at dynamic study, lack of enhancement or "entrapment" at hepatobiliary phase, and target appearance on DWI are frequent findings of HEH.

Impact on liver cancer treatment of a first erroneous diagnosis of hemangioma.

BACKGROUND: Most liver hemangioma (HA) diagnoses are presumptive and based on radiological features and growth trend. The goal of this study was to analyze the impact of a false diagnosis of hemangioma upon the overall therapeutic course and upon the prognosis of a liver malignancy. METHODS: Twenty-eight patients with liver cancer who were observed in the period 2001-2007 after an initial erroneous diagnosis of HA were retrospectively evaluated. We studied their radiological workup after blind revision of the images by two radiologists with specific expertise in liver imaging, analyzing the relationship between overall management and center volume, mean delay from the first test to the curative treatment, and clinical consequences of this diagnostic mistake. RESULTS: The diagnosis of false HA occurred in a low-volume center (LVC) in 75 % of cases. A specific risk for liver cancer was present in 71.4 % of patients. US gave a false diagnosis of HA in 25/27 patients, a CT scan in 18/25 patients, and MRI in 6/16 patients. The final diagnosis was reached with a mean delay of 22 months. Liver resection was possible in 22 patients; in the 17 hepatocellular carcinoma cases, the survival rate was 69.4 % at 5 years after the first observation. CONCLUSIONS: A false diagnosis of HA in the presence of malignancy is not rare nowadays and significantly reduces the chances of cure. In situations at risk of having the error occur (poor technical quality of imaging, low specific experience, doubtful diagnosis, and high-cancer-risk patient), the rationale approach is to discuss the case with a multidisciplinary team skilled in the field of liver cancer.

Diffusion-weighted magnetic resonance imaging in the prediction and assessment of chemotherapy outcome in liver metastases.

PURPOSE: This study assessed the capability of magnetic resonance (MR) diffusion-weighted imaging (DwI) with measurement of apparent diffusion coefficient (ADC) in both predicting and evaluating the response to chemotherapy (CHT) of liver metastases by itself and along with preliminary dimensional assessment. METHODS AND MATERIALS: Patients affected by liver metastases from cancers of the digestive tract and breast were prospectively enrolled and underwent computed tomography and MR-DwI before CHT (time 0) and 20-25 days after the beginning of the second cycle (time 3). Moreover, MR-DwI was performed 10-15 (time 1) and 20-25 days (time 2) after the beginning of the first cycle. Maximum diameter and mean ADC value (×10(-3) mm(2)/s) of metastases were evaluated. Lesions were classified as progressive disease (PD), stable disease (SD) or partial response (PR) according to dimensional changes between time 0 and time 3, following RECIST 1.1 indications. Clinically, PD lesions were defined as nonresponding (NR), and SD and PR lesions as responding (R). Analysis of variance and ROC analyses were performed (significance at p < 0.05). RESULTS: Eighty-six metastases (33 patients) were classified as follows: 15 PD, 39 SD and 32 PR without significant differences in mean ADC values among the groups before CHT and at all corresponding times. The mean ADC values of SD and PR groups at times 1 (respectively 1.66 ± 0.36 and 1.59 ± 0.23), 2 (1.72 ± 0.42 and 1.68 ± 0.37) and 3 (1.86 ± 0.44 and 1.73 ± 0.39) were significantly higher than the corresponding values at time 0 (1.50 ± 0.30 and 1.39 ± 0.33). An accurate cutoff value of ADC increase or diameter decrease for the early identification of R or NR lesions was not found. CONCLUSION: The pretreatment ADC value of a liver metastasis does not seem useful in predicting the CHT outcome. A trend towards early ADC increase, alone or occurring with dimensional decrease, may be a good indicator of a responding lesion.

A unique case of lymphoepithelioma-like HCC with osteoclast-like giant cells: CT imaging features with pathologic correlations.

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver, with several histological variants being reported in literature. Hereby, we describe a case of a 77-year-old man with chronic liver disease referred to our department for performing a computed tomography (CT) due to a liver mass discovered at an abdominal ultrasound follow-up. At CT, a large, ill-defined lesion in the third hepatic segment was detected, characterized by progressive and delayed enhancement with minimal retraction of the hepatic capsule, associated with perihepatic adipose tissue inhomogeneity, mimicking a cholangiocarcinoma. At histopathological evaluation, the lesion turned out to be an HCC with lymphoepithelioma-like component and osteoclastic-like giant cells. This report focuses on the clinicopathological and radiological features of this unique case.

Intra-patient and inter-observer image quality analysis in liver MRI study with gadoxetic acid using two different multi-arterial phase techniques.

PURPOSE: To evaluate intra-patient and interobserver agreement in patients who underwent liver MRI with gadoxetic acid using two different multi-arterial phase (AP) techniques. METHODS: A total of 154 prospectively enrolled patients underwent clinical gadoxetic acid-enhanced liver MRI twice within 12 months, using two different multi-arterial algorithms: CAIPIRINHA-VIBE and TWIST-VIBE. For every patient, breath-holding time, body mass index, sex, age were recorded. The phase without contrast media and the APs were independently evaluated by two radiologists who quantified Gibbs artefacts, noise, respiratory motion artefacts, and general image quality. Presence or absence of Gibbs artefacts and noise was compared by the McNemar's test. Respiratory motion artefacts and image quality scores were compared using Wilcoxon signed rank test. Interobserver agreement was assessed by Cohen kappa statistics. RESULTS: Compared with TWIST-VIBE, CAIPIRINHA-VIBE images had better scores for every parameter except higher noise score. Triple APs were always acquired with TWIST-VIBE but failed in 37% using CAIPIRINHA-VIBE: 11% have only one AP, 26% have two. Breath-holding time was the only parameter that influenced the success of multi-arterial techniques. TWIST-VIBE images had worst score for Gibbs and respiratory motion artefacts but lower noise score. CONCLUSION: CAIPIRINHA-VIBE images were always diagnostic, but with a failure of triple-AP in 37%. TWIST-VIBE was successful in obtaining three APs in all patients. Breath-holding time is the only parameter which can influence the preliminary choice between CAIPIRINHA-VIBE and TWIST-VIBE algorithm. ADVANCES IN KNOWLEDGE: If the patient is expected to perform good breath-holds, TWIST-VIBE is preferable; otherwise, CAIPIRINHA-VIBE is more appropriate.

Comparing Visual and Software-Based Quantitative Assessment Scores of Lungs' Parenchymal Involvement Quantification in COVID-19 Patients.

(1) Background: Computed tomography (CT) plays a paramount role in the characterization and follow-up of COVID-19. Several score systems have been implemented to properly assess the lung parenchyma involved in patients suffering from SARS-CoV-2 infection, such as the visual quantitative assessment score (VQAS) and software-based quantitative assessment score (SBQAS) to help in managing patients with SARS-CoV-2 infection. This study aims to investigate and compare the diagnostic accuracy of the VQAS and SBQAS with two different types of software based on artificial intelligence (AI) in patients affected by SARS-CoV-2. (2) Methods: This is a retrospective study; a total of 90 patients were enrolled with the following criteria: patients' age more than 18 years old, positive test for COVID-19 and unenhanced chest CT scan obtained between March and June 2021. The VQAS was independently assessed, and the SBQAS was performed with two different artificial intelligence-driven software programs (Icolung and CT-COPD). The Intraclass Correlation Coefficient (ICC) statistical index and Bland-Altman Plot were employed. (3) Results: The agreement scores between radiologists (R1 and R2) for the VQAS of the lung parenchyma involved in the CT images were good (ICC = 0.871). The agreement score between the two software types for the SBQAS was moderate (ICC = 0.584). The accordance between Icolung and the median of the visual evaluations (Median R1-R2) was good (ICC = 0.885). The correspondence between CT-COPD and the median of the VQAS (Median R1-R2) was moderate (ICC = 0.622). (4) Conclusions: This study showed moderate and good agreement upon the VQAS and the SBQAS; enhancing this approach as a valuable tool to manage COVID-19 patients and the combination of AI tools with physician expertise can lead to the most accurate diagnosis and treatment plans for patients.

Consensus report of the Fifth International Forum for Liver MRI.

OBJECTIVE: This article reviews topics discussed during the Fifth International Forum for Liver MRI (with a focus on gadoxetic acid-enhanced MRI), which was held in Munich, Germany, in September 2011. CONCLUSION: Growing evidence shows that gadoxetic acid-enhanced MRI has high sensitivity and specificity for diagnosing liver tumors. Hepatobiliary phase imaging adds new information for the characterization of borderline lesions. However, there is a need to develop standardized criteria for interpretation of gadoxetic acid-enhanced MRI in patients with cirrhosis or other risk factors for hepatocellular carcinoma.