High-frequency ultrasonography for subungual glomus tumor evaluation - imaging findings.

OBJECTIVE: This article aimed to describe the common imaging features of subungual glomus tumors. METHODS: The study involved data collected between January 2019 and December 2022. Twenty-three patients with a total of 31 glomus tumors underwent high-frequency ultrasound examinations with a 24-MHz probe. Two experienced radiologists independently evaluated the images, and only data from the more experienced radiologist were used for subsequent analyses. RESULTS: The average size of the tumors was 4.6 mm, and most of them appeared homogeneously hypoechogenic (90.3%). Bone remodeling of the distal phalanx was observed in 87.1% of cases, with an average axial circumference loss of 0.8 mm, indicating the slow and expansive growth of glomus tumors. Intense vascularization was found in 54.8% of cases on Doppler images, and the stalk sign, reflecting the vascular origin of the tumor, was present in 64.5% of cases. The most common clinical feature was pain, reported in 84.6% of cases, with a mean pain scale score of 7.0, indicating a negative impact on patients' lives despite being benign tumors. CONCLUSION: The study concludes that ultrasound evaluation is highly useful for diagnosing glomus tumors, especially when multiple findings, such as bone remodeling, hypervascularization, and the stalk sign, are present. This method allows for accurate diagnosis, observation of periungual structures, and proper surgical planning, ultimately reducing recurrence rates.

Imaging Findings in Aspergillosis: From Head to Toe.

Aspergillosis is a mycotic infection induced by airborne fungi that are ubiquitous. Inhalation of Aspergillus conidia results in transmission through the respiratory tract. The clinical presentation is dependent on organism and host specifics, with immunodeficiency, allergies, and preexisting pulmonary disease constituting the most important risk factors. In recent decades, the incidence of fungal infections has increased dramatically, due in part to the increased number of transplants and the pervasive use of chemotherapy and immunosuppressive drugs. The spectrum of clinical manifestations can range from an asymptomatic or mild infection to a swiftly progressive, life-threatening illness. Additionally, invasive infections can migrate to extrapulmonary sites, causing infections in distant organs. Recognition and familiarity with the various radiological findings in the appropriate clinical context are essential for patient management and the prompt initiation of life-saving treatment. We discuss the radiological characteristics of chronic and invasive pulmonary aspergillosis, as well as some of the typically unexpected extrapulmonary manifestations of disseminated disease.

Hepatic involvement in hereditary hemorrhagic telangiectasia mimicking focal nodular hyperplasia.

Accurate diagnosis of hereditary hemorrhagic telangiectasia (HHT), also known as Rendu-Osler-Weber disease, is important for reducing the risk of complications. Hepatic involvement in HHT is usually asymptomatic, but when present can cause noted morbidity and mortality. A 62-year-old woman presented with moderate upper-abdominal pain and tachycardia. A diagnosis of HHT was made based on the findings of hepatic involvement in a contrast-enhanced abdominal computed tomography (CT) scan, the presence of arteriovenous malformations (AVMs; a.k.a. telangiectasias) on mucocutaneous surfaces, and a history of recurrent epistaxis. Imaging methods are important diagnostic tools in patients suspected of having HHT.

Chest MRI with CT in the assessment of interstitial lung disease progression in patients with systemic sclerosis.

OBJECTIVE: To describe the performance of CT and MRI in the assessment of the progression of interstitial lung disease (ILD) associated with SSc and demonstrate the correlations of MRI with pulmonary function test (PFT) and CT scores. METHODS: This prospective single-centre observational study included patients with SSc diagnoses, and magnetic resonance (MR) images were assessed visually using the Scleroderma Lung Study (SLS) I system. Differences in the median scores were assessed with Student's t-test and the Wilcoxon rank-sum test. Pearson's and Spearman's rank correlation coefficients were calculated to correlate imaging scores and PFT results. Using disease progression as the gold standard, we calculated the area under the curve (AUC) of the CT and MRI scores with Harrel's c-index. The best thresholds for the prediction of disease progression were determined by receiver operating characteristic curve analysis with maximum Youden's Index (P < 0.05). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the scores were calculated. RESULTS: The AUCs for MRI and CT scores were 0.86 (0.72-0.98; P = 0.04) and 0.83 (0.70-0.99; P = 0.05), respectively. CT and MRI scores correlated with Forced vital capacity (%FVC) (MRI: r = -0.54, P = 0.0045; CT: r = -0.44; P = 0.137) and diffusing capacity of the lung for carbon monoxide (MRI: r = -0.39, P = 0.007; CT r = -0.36, P = 0.006). The sensitivity, specificity, PPV and NPV were 85%, 87.5%, 88.34% and 86.11% (MRI score) and 84.21%, 82.35%, 84.14% and 82.4% (CT score), respectively. CONCLUSIONS: MRI scores from patients with SSc may be an alternative modality for the assessment of ILD progression in patients with SSc.

Human Oncoviruses and Thoracic Tumors: Understanding the Imaging Findings.

Approximately 1.4 million virus-induced cancers occur annually, representing roughly 10% of the cancer burden worldwide. Seven oncogenic DNA and RNA viruses (ie, oncoviruses) are implicated in approximately 12%-25% of all human cancers owing to a variety of mechanisms as uncommon consequences of the normal viral life cycle. These seven well-recognized human oncoviruses are Epstein-Barr virus (EBV), human T-lymphotropic virus 1, hepatitis B virus, hepatitis C virus, HIV, human papilloma virus (HPV), and human herpesvirus 8 (HHV-8). Several viruses-namely, EBV, HPV, and Kaposi sarcoma herpesvirus or HHV-8-are increasingly being recognized as being related to HIV and/or AIDS, the growing number of transplant cases, and the use of immunosuppressive therapies. Infectious and inflammatory processes, and the accompanying lymphadenopathy, are great mimickers of human oncovirus-related tumors. Although it is often difficult to differentiate these entities, the associated clinical setting and radiologic findings may provide clues for an accurate diagnosis and appropriate management. Malignant lymphoid lesions are best evaluated with multidetector chest CT. The radiologic findings of these lesions are often nonspecific and are best interpreted in correlation with clinical data and histopathologic findings. ©RSNA, 2022.

The impact of cardiopulmonary hemodynamic factors in volumetry for pulmonary nodule management.

BACKGROUND: The acceptance of coronary CT angiogram (CCTA) scans in the management of stable angina has led to an exponential increase in studies performed and reported incidental findings, including pulmonary nodules (PN). Using low-dose CT scans, volumetry tools are used in growth assessment and risk stratification of PN between 5 and 8 mm in diameter. Volumetry of PN could also benefit from the increased temporal resolution of CCTA scans, potentially expediting clinical decisions when an incidental PN is first detected on a CCTA scan, and allow for better resource management and planning in a Radiology department. This study aims to investigate how cardiopulmonary hemodynamic factors impact the volumetry of PN using CCTA scans. These factors include the cardiac phase, vascular distance from the main pulmonary artery (MPA) to the nodule, difference of the MPA diameter between systole and diastole, nodule location, and cardiomegaly presence. MATERIALS AND METHODS: Two readers reviewed all CCTA scans performed from 2016 to 2019 in a tertiary hospital and detected PN measuring between 5 and 8 mm in diameter. Each observer measured each nodule using two different software packages and in systole and diastole. A multiple linear regression model was applied, and inter-observer and inter-software agreement were assessed using intraclass correlation. RESULTS: A total of 195 nodules from 107 patients were included in this retrospective, cross-sectional and observational study. The regression model identified the vascular distance (p < 0.001), the difference of the MPA diameter between systole and diastole (p < 0.001), and the location within the lower or posterior thirds of the field of view (p < 0.001 each) as affecting the volume measurement. The cardiac phase was not significant in the model. There was a very high inter-observer agreement but no reasonable inter-software agreement between measurements. CONCLUSIONS: PN volumetry using CCTA scans seems to be sensitive to cardiopulmonary hemodynamic changes independently of the cardiac phase. These might also be relevant to non-gated scans, such as during PN follow-up. The cardiopulmonary hemodynamic changes are a new limiting factor to PN volumetry. In addition, when a patient experiences an acute or deteriorating cardiopulmonary disease during PN follow-up, these hemodynamic changes could affect the PN growth estimation.

Narrowing the Differential Diagnosis of Cystic Lesions in Smokers with Expiratory CT Acquisition Using the Cyst-Airway Communication Hypothesis.

The aim of this study was to assess percentage respiratory changes (δ) in the size of pulmonary cysts of different smoking-related etiologies. Retrospectively, we measured the cystic lesions due to histopathological-confirmed honeycombing from interstitial pulmonary fibrosis, pulmonary Langerhans cell histiocytosis (PLCH), and paraseptal emphysema, using paired inspiratory and expiratory CT scans. In a sample of 72 patients and 216 lesions, the mean diameter of PLCH and honeycombing decreased during expiration (PLCH, δ = 60.9%; p = 0.001; honeycombing, δ = 47.5%; p = 0.014). Conversely, paraseptal emphysema did not show any changes (δ = 5.2%; p = 0.34). In summary, our results demonstrated that cysts in smokers with PLCH and honeycombing fibrosis get smaller during expiratory CT scans, whereas the size of cystic-like lesions due to paraseptal emphysema and bullae tend to remain constant during respiratory cycles. These results support the hypothesis of cyst-airway communication in some cystic diseases, which could assist in the differential diagnosis in smoking-related lung diseases.

Venolymphatic malformations: prenatal diagnosis using magnetic resonance imaging, perinatal outcomes and long-term follow-up.

BACKGROUND: Venolymphatic malformations are benign. Fetal MRI can more precisely demonstrate an infiltrative pattern of malformations than US. OBJECTIVE: To evaluate perinatal outcomes and long-term follow-up of fetal venolymphatic malformations treated in different medical facilities using fetal MRI. MATERIALS AND METHODS: This retrospective cohort study evaluated 20 pregnant women between 22 weeks and 37 weeks of gestation who were referred from different institutions. They presented with fetuses with various diagnoses of cystic masses on routine US. The cases were studied using MRI. We analyzed prenatal data, perinatal outcomes and long-term follow-up. RESULTS: We reviewed the MRI scans of 20 patients with venolymphatic malformation. Referral diagnosis was changed in 40% (8/20) of cases, with postnatal concordance of 100% (20/20). Moreover, 65% (13/20) presented with venolymphatic malformation in more than one body segment. The neck was affected in 70% (14/20) of fetuses, while the head and thorax were affected in 30% (6/20) and 45% (9/20), respectively. There were intrathoracic lesions in 35% (7/20), lesions in the abdomen in 30% (6/20), and lesions in the perineum and extremities in 10% (2/20) each. Tracheal displacement, neck deflection and anatomical displacement caused by tumoral compression were present in 15% (3/20) of cases. Moreover, 25% (5/20) of newborns required neonatal intensive care unit admission, and all presented with cervical or thoracic venolymphatic malformation. Furthermore, 50% (10/20) of cases presented with complete resolution after medical therapy. The intrathoracic and cervical residuals (35%, 7/20) were monitored and treated. CONCLUSION: MRI showed good correlation with postnatal examination of venolymphatic malformation, was useful in the differential diagnosis of fetal cysts on US, and presented a significant postnatal correlation with thoracic infiltration. The outcomes of prenatally diagnosed venolymphatic malformations are good despite the varying protocols among medical facilities.

Comparison of the computed tomography findings in COVID-19 and other viral pneumonia in immunocompetent adults: a systematic review and meta-analysis.

OBJECTIVES: To compare the chest computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) to other non-COVID viral pneumonia. METHODS: MEDLINE, EMBASE, and Cochrane databases were searched through April 04, 2020, for published English language studies. Studies were eligible if they included immunocompetent patients with up to 14 days of viral pneumonia. Subjects had a respiratory tract sample test positive for COVID-19, adenovirus, influenza A, rhinovirus, parainfluenza, or respiratory syncytial virus. We only included observational studies and case series with more than ten patients. The pooled prevalence of each chest CT pattern or finding was calculated with 95% confidence intervals (95% CI). RESULTS: From 2263 studies identified, 33 were eligible for inclusion, with a total of 1911 patients (COVID-19, n = 934; non-COVID, n = 977). Frequent CT features for both COVID-19 and non-COVID viral pneumonia were a mixed pattern of ground-glass opacity (GGO) and consolidation (COVID-19, 0.37; 0.17-0.56; non-COVID, 0.46; 0.35-0.58) or predominantly GGO pattern (COVID-19, 0.42; 0.28-0.55; non-COVID 0.25; 0.17-0.32), bilateral distribution (COVID-19, 0.81; 0.77-0.85; non-COVID, 0.69; 0.54-0.84), and involvement of lower lobes (COVID-19, 0.88; 0.80-0.95; non-COVID, 0.61; 0.50-0.82). COVID-19 pneumonia presented a higher prevalence of peripheral distribution (COVID-19 0.77; 0.67-0.87; non-COVID 0.34; 0.18-0.49), and involvement of upper (COVID-19, 0.77; 0.65-0.88; non-COVID 0.18; 0.10-0.27) and middle lobes (COVID-19, 0.61; 0.47-0.76; non-COVID 0.24; 0.11-0.38). CONCLUSION: Except for a higher prevalence of peripheral distribution, involvement of upper and middle lobes, COVID-19, and non-COVID viral pneumonia had overlapping chest CT findings. KEY POINTS: • Most common CT findings of coronavirus disease 2019 (COVID-19) were a predominant pattern of ground-glass opacity (GGO), followed by a mixed pattern of GGO and consolidation, bilateral disease, peripheral distribution, and lower lobe involvement. • Most frequent CT findings of non-COVID viral pneumonia were a predominantly mixed pattern of GGO and consolidation, followed by a predominant pattern of GGO, bilateral disease, random or diffuse distribution, and lower lobe involvement. • COVID-19 pneumonia presented a higher prevalence of peripheral distribution, and involvement of upper and middle lobes compared with non-COVID viral pneumonia.

Frequency and Reliability of the Reversed Halo Sign in Patients With Septic Pulmonary Embolism Due to IV Substance Use Disorder.

OBJECTIVE. The purpose of this article is to assess the "reversed halo" sign in patients with septic pulmonary embolism (PE) due to IV substance use disorder. MATERIALS AND METHODS. A retrospective analysis was performed of chest CT scans obtained between 2007 and 2017 that had findings of septic PE associated with IV substance use disorder. Inclusion criteria were history of IV substance use disorder, findings of septic PE on chest CT scans, and confirmation of infection. Image analysis was performed by three radiologists to assess the frequency, appearance, and evolution of the reversed halo sign. Interreader agreement to characterize the reversed halo sign was assessed using kappa statistical analysis. The chi-square test was used to correlate reversed halo sign shape with evolution on follow-up scans. RESULTS. Of 62 patients who met the inclusion criteria (54.8% women; mean age, 32.8 ± 8.3 [SD] years), 59.7% (37/62) had reversed halo signs (κ = 0.837-0.958, p < 0.0001). The mean number of unique reversed halo signs per patient was 2.1 ± 1.7 (46.7% of patients had more than one reversed halo sign). Of 78 unique reversed halo signs, 93.6% (73/78) were peripherally located and 51.3% (40/78) were located at the lower lobe, 52.6% (41/78) were pyramidal and 47.4% (37/78) were round shaped, 89.7% (70/78) had central low-attenuation areas, and 34.6% (27/78) had internal reticulations. Cavitation developed in 37.2% (29/78) of reversed halo signs and more often in pyramid-shaped ones (70.8%, 17/24), whereas consolidation occurred in 30.8% (24/78) and more often in round-shaped ones (58.6%; 17/29, p = 0.03). CONCLUSION. Septic PE should be considered in the differential diagnosis of patients with IV substance use disorder presenting with reversed halo sign. The reversed halo sign was reliably and frequently observed on the chest CT scans of patients with IV substance use disorder-related septic PE. Characteristics of reversed halo sign presentation were identified as potential features to differentiate septic PE from other causes of pulmonary infarct manifesting with reversed halo sign.

What We Can Find Beyond the Classic Neuroimaging Findings of Congenital Zika Virus Syndrome?

BACKGROUND: In 1947, Zika virus (ZIKV) was first discovered in Monkeys, in Zika Forest, in Uganda, Africa. Five years later, (1952) the first human Zika infection was detected in Nigeria, Africa. After this date, only sporadic cases happened, until the first 3 epidemics occurred, all outside Africa. The first epidemic was in Yap Island in 2007, the second in French Polynesia in 2013, and the third in 2015 in the northeast of Brazil, and then the spread to the Americas in 2015 and 2016. However, it was only after the epidemic in the northeast of Brazil, in the first half of 2015, that many babies were born with microcephaly in the second semester of that same year and in 2016. Until now, every year, some babies are still born with congenital ZIKV syndrome (CZVS). SUMMARY: The objective of this article is to describe infrequent and rarely discussed imaging (computed tomography and magnetic resonance imaging) findings of CZVS, in addition to those classically described such as a simplified gyral pattern, ventriculomegaly, corpus callosum dysgenesis, craniofacial disproportion, and redundant scalp, thus suggesting an increase in the spectrum of neurological findings related to the syndrome.

Bipartite medial cuneiform: magnetic resonance imaging findings and prevalence of this rare anatomical variant.

OBJECTIVE: To describe the imaging features of bipartite medial cuneiform and to determine the prevalence of this rare anatomical variant in a large group of patients that were evaluated by magnetic resonance imaging (MRI) of the foot. MATERIALS AND METHOD: Seven hundred and fifty-one patients that underwent MRI of the foot from May 2016 to December 2018 were included in the study (mean age 49 years; 540 females; 211 males). All MRIs were retrospectively analyzed to identify bipartite medial cuneiform. For patients with bipartite medial cuneiform, we analyzed partial and complete bipartition, the type of articulation (synchondrosis, syndesmosis, or a combination of these two), and stress changes related to abnormal motion (i.e., subchondral cysts and sclerosis). Bone marrow edema-like signal, diastasis in the cleavage plane, concomitant fractures, and the presence of the E-sign were also evaluated. RESULTS: Nine feet from six patients presented bipartite medial cuneiform on the MRI. Six and three feet exhibited complete and partial bipartition. All patients were referred for MRI because of midfoot pain, of which two had history of trauma prior to imaging. Stress changes related to abnormal motion were observed in three feet (34%), all with complete bipartition. Bone marrow edema-like signal was recorded in five feet (55%) and diastasis in one foot (11%). No fractures were present in the bipartite medial cuneiform. All patients had E-signs. CONCLUSION: Bipartite medial cuneiform is a rare anatomical variant occurring in 0.79% of patients who underwent foot MRI in this study. It is important to be aware of this variant as it is a cause of midfoot pain. Being familiar with the E-sign helps identify and differentiate it from a fracture.

Fluorine 18-FDG PET/CT and Diffusion-weighted MRI for Malignant versus Benign Pulmonary Lesions: A Meta-Analysis.

Purpose To perform a meta-analysis of the literature to compare the diagnostic performance of fluorine 18 fluorodeoxyglucose PET/CT and diffusion-weighted (DW) MRI in the differentiation of malignant and benign pulmonary nodules and masses. Materials and Methods Published English-language studies on the diagnostic accuracy of PET/CT and/or DW MRI in the characterization of pulmonary lesions were searched in relevant databases through December 2017. The primary focus was on studies in which joint DW MRI and PET/CT were performed in the entire study population, to reduce interstudy heterogeneity. For DW MRI, lesion-to-spinal cord signal intensity ratio and apparent diffusion coefficient were evaluated; for PET/CT, maximum standard uptake value was evaluated. The pooled sensitivities, specificities, diagnostic odds ratios, and areas under the receiver operating characteristic curve (AUCs) for PET/CT and DW MRI were determined along with 95% confidence intervals (CIs). Results Thirty-seven studies met the inclusion criteria, with a total of 4224 participants and 4463 lesions (3090 malignant lesions [69.2%]). In the primary analysis of joint DW MRI and PET/CT studies (n = 6), DW MRI had a pooled sensitivity and specificity of 83% (95% CI: 75%, 89%) and 91% (95% CI: 80%, 96%), respectively, compared with 78% (95% CI: 70%, 84%) (P = .01 vs DW MRI) and 81% (95% CI: 72%, 88%) (P = .056 vs DW MRI) for PET/CT. DW MRI yielded an AUC of 0.93 (95% CI: 0.90, 0.95), versus 0.86 (95% CI: 0.83, 0.89) for PET/CT (P = .001). The diagnostic odds ratio of DW MRI (50 [95% CI: 19, 132]) was superior to that of PET/CT (15 [95% CI: 7, 32]) (P = .006). Conclusion The diagnostic performance of diffusion-weighted MRI is comparable or superior to that of fluorine 18 fluorodeoxyglucose PET/CT in the differentiation of malignant and benign pulmonary lesions. © RSNA, 2018 Online supplemental material is available for this article. See also the editorial by Schiebler in this issue.

Pulmonary Acinus: Understanding the Computed Tomography Findings from an Acinar Perspective.

The lung acinus is the most distal portion of the airway responsible for the gas exchange. The normal acini are not visible on conventional computed tomography (CT), but the advent of micro-CT improved the understanding of the microarchitecture of healthy acini. The comprehension of the acinar architecture is pivotal for the understanding of CT findings of diseases that involve the acini. Centriacinar emphysema, for example, presents as round areas of low attenuation due to the destruction of the most central acini with compensatory enlargement of proximal acini due to alveolar wall destruction. In pulmonary fibrosis, intralobular septal fibrosis manifests as acinar wall thickening with an overlap of acinar collapse and compensatory dilation of surrounding acini constituting the cystic disease typical of the usual interstitial pneumonia pattern. This is a state-of-the-art review to describe the acinar structure from the micro-CT perspective and display how the comprehension of the acinar structure can aid in the interpretation of its microarchitecture disruption on conventional CT.

The human endosalpinx: anatomical three-dimensional study and reconstruction using confocal microtomography.

PURPOSE: To evaluate in three dimensions (3D) the human endosalpinx and reconstruct its surface along its different anatomical segments, without the injection or insertion of luminal contrasts, using confocal microtomography (micro-CT). MATERIAL AND METHODS: 15 fallopian tubes (FT) from 14 women in reproductive age from procedures for benign disease or sterilization were selected. The specimens were fixed in formalin and stained with Lugol solution. Micro-CT studies were conducted on the specimens using protocols adapted from biological studies, to acquire images to reconstruct in 3D the endosalpinx surface. RESULTS: From these specimens, 6 presented the intra-mural segment, 14 presented the isthmus and 15 presented the ampulla and fimbria segment of the FT. The specimen presented tissue definition, and contrast sufficient for FT endosalpinx morphological analysis and lumen definition. The intramural portion presented initially a mucosal projection toward the lumen, bending on its own axis, and increased numbers of projections towards the isthmic portion, where the projections become longer more numerous. The endosalpinx becomes more tortuous, the lumen diameter increases and the mucosal projections become more bulky in the ampullary portion, with the projections less present on the antimesenteric side. The infundibular portion is marked with the organized and predictable endosalpinx, the abdominal ostium is cleared demonstrated, with the reduction of the endosalpinx volume. The fimbria demonstrated a small relation between fringes and intratubal endosalpinx. CONCLUSIONS: Microscopic anatomy of different segments of the human FT mucosa can be analyzed and reconstructed in 3D with histological correlation using micro-CT.

Multiparametric Magnetic Resonance Imaging in the Assessment of Pulmonary Hypertension: Initial Experience of a One-Stop Study.

INTRODUCTION: Our goal was to assess the diagnostic performance of magnetic resonance imaging (MRI) as a single method to diagnose pulmonary hypertension (PH) compared to right heart catheterization (RHC), computed tomography (CT), and ventilation/perfusion (V/Q) scintigraphy. METHODS: We identified 35 patients diagnosed with PH by RHC in our institution who have also undergone a CT, a scintigraphy, and an MRI within a month. All cases were discussed in multidisciplinary meetings. We performed correlations between the MRI-derived hemodynamic parameters and those from RHC. The sensitivity and specificity of MRI were determined to identify its diagnostic performance to identify chronic thromboembolic pulmonary hypertension (CTEPH) and interstitial lung disease PH. The gold standard reference for the diagnosis of CTEPH and ILD was based on a review of multimodality imaging (V/Q scintigraphy and CT scan) and clinical findings. RESULTS: Our results showed a good correlation between the hemodynamic parameters of cardiac MRI and RHC. Pulmonary vascular resistance had the best correlation between both methods (r = 0.923). The sensitivity and specificity of MRI to diagnose CTEPH was 100 and 96.8%, respectively. For the ILD-related PH, the MRI yielded a sensitivity of 60.0% and a specificity of 100%. Additionally, cardiac MRI was able to confirm all cases of PAH due to congenital heart disease initially detected by echocardiography. CONCLUSIONS: MRI represents a promising imaging modality as an initial, single-shot study, for patients with suspected PH with the advantages of being non-invasive and having no radiation exposure.

Infectious and Non-Infectious Diseases Causing the Air Crescent Sign: A State-of-the-Art Review.

Aspergilloma, also known as mycetoma or fungus ball, is characterized by a round or oval mass with soft-tissue attenuation within a preexisting lung cavity. The typical computed tomography (CT) aspect of an aspergilloma is a mass separated from the wall of the cavity by an airspace of variable size and shape, resulting in the air crescent sign, also known as the meniscus sign. This CT feature is non-specific and can be simulated by several other entities that result in intracavitary masses. This review describes the main clinical and imaging aspects of the infectious and non-infectious diseases that may present with fungus-ball appearance, including pulmonary hydatid cyst, Rasmussen aneurysm, pulmonary gangrene, intracavitary clot, textiloma, lung cancer, metastasis, and teratoma, focusing on the differential diagnosis.

Correction to: Multiparametric Magnetic Resonance Imaging in the Assessment of Pulmonary Hypertension: Initial Experience of a One-Stop Study.

The original version of this article unfortunately contained a mistake. There is a typo in the coauthor name, it should be Stephan Altmayer.

Advances in Imaging and Automated Quantification of Malignant Pulmonary Diseases: A State-of-the-Art Review.

Quantitative imaging in lung cancer is a rapidly evolving modality in radiology that is changing clinical practice from a qualitative analysis of imaging features to a more dynamic, spatial, and phenotypical characterization of suspected lesions. Some quantitative parameters, such as the use of 18F-FDG PET/CT-derived standard uptake values (SUV), have already been incorporated into current practice as it provides important information for diagnosis, staging, and treatment response of patients with lung cancer. A growing body of evidence is emerging to support the use of quantitative parameters from other modalities. CT-derived volumetric assessment, CT and MRI lung perfusion scans, and diffusion-weighted MRI are some of the examples. Software-assisted technologies are the future of quantitative analyses in order to decrease intra- and inter-observer variability. In the era of "big data", widespread incorporation of radiomics (extracting quantitative information from medical images by converting them into minable high-dimensional data) will allow medical imaging to surpass its current status quo and provide more accurate histological correlations and prognostic value in lung cancer. This is a comprehensive review of some of the quantitative image methods and computer-aided systems to the diagnosis and follow-up of patients with lung cancer.

Synovitis of the knee following a high-pressure injection injury with hydraulic oil.

High-pressure injection injuries occur when equipment capable of achieving high pressure injects its contents into the human body. These injuries are largely occupational and may present as small entrance wounds with very few symptoms. However, they represent a surgical emergency, often requiring amputation. They characteristically involve the upper extremities, but other regions of the body may be injured. We present the case of a 26-year-old man who sustained a high-pressure injection injury with hydraulic oil to the knee and a literature review of this type of accident. To our knowledge, this report is the first to describe such an injury to the knee, with magnetic resonance imaging findings.