CT angiography for the assessment of EVAR complications: a pictorial review.

Endovascular aneurysm repair (EVAR) is a minimally invasive treatment proposed as an alternative to open repair in patients with abdominal aortic aneurysms. EVAR consists in a stent-graft placement within the aorta in order to exclude the aneurysm from arterial circulation and reduce the risk of rupture. Knowledge of the various types of devices is mandatory because some stents/grafts are more frequently associated with complications. CT angiography is the gold standard diagnostic technique for preprocedural planning and postprocedural surveillance. EVAR needs long-term follow-up due to the high rate of complications. Complications can be divided in endograft device-related and systemic complications. The purpose of this article is to review the CT imaging findings of EVAR complications and the key features for the diagnosis.

PI-RADS 3 Lesions: Role of Prostate MRI Texture Analysis in the Identification of Prostate Cancer.

PURPOSE: To determine the diagnostic performance of texture analysis of prostate MRI for the diagnosis of prostate cancer among Prostate Imaging Reporting and Data System (PI-RADS) 3 lesions. MATERIALS AND METHODS: Forty-three patients with at least 1 PI-RADS 3 lesion on prostate MRI performed between June 2016 and January 2019 were retrospectively included. Reference standard was pathological analysis of radical prostatectomy specimens or MRI-targeted biopsies. Texture analysis extraction of target lesions was performed on axial T2-weighted images and apparent diffusion coefficient (ADC) maps using a radiomic software. Lesions were categorized as prostate cancer (Gleason score [GS] ≥ 6), and no prostate cancer. Statistical analysis was performed using the generalized linear model (GLM) regression and the discriminant analysis (DA). AUROC with 95% confidence intervals were calculated to assess the diagnostic performance of standalone features and predictive models for the diagnosis of prostate cancer (GS ≥ 6) and clinically-significant prostate cancer (GS ≥ 7). RESULTS: The analysis of 46 PI-RADS 3 lesions (ie, 27 [58.7%] no prostate cancers; 19 [41.3%] prostate cancers) revealed 9 and 6 independent texture parameters significantly correlated with the final histopathological results on T2-weighted and ADC maps images, respectively. The resulting GLM and DA predictive models for the diagnosis of prostate cancer yielded an AUROC of 0.775 and 0.779 on T2-weighted images or 0.815 and 0.821 on ADC maps images. For the diagnosis of clinically-significant prostate cancer, the resulting GLM and DA predictive models for the diagnosis of prostate cancer yielded an AUROC of 0.769 and 0.817 on T2-weighted images or 0.749 and 0.744 on ADC maps images. CONCLUSION: Texture analysis of PI-RADS 3 lesions on T2-weighted and ADC maps images helps identifying prostate cancer. The good diagnostic performance of the combination of multiple radiomic features for the diagnosis of prostate cancer may help predicting lesions where aggressive management may be warranted.

Color Doppler Ultrasound in Portal Hypertension: A Closer Look at Left Gastric Vein Hemodynamics.

Portal hypertension is one of the most important causes of morbidity and mortality in cirrhotic patients. A color Doppler evaluation of the left gastric vein (LGV) has proven utility in the prediction of esophageal varices and variceal bleeding in patients with portal hypertension. The purpose of this review is to discuss the ultrasound evaluation, imaging findings, and clinical application of Doppler ultrasound in the assessment of the LGV. Knowledge of the color Doppler technique and imaging findings of the LGV may help clinicians improve the monitoring of portal hypertension and predict patients with a high risk of esophageal varices.

Radiographic and chest CT imaging presentation and follow-up of COVID-19 pneumonia: a multicenter experience from an endemic area.

COVID-19 has infected more than 2 million people in the world in less than 5 months outbreak. Chest imaging is recommended for triage of suspected cases of COVID-19 with moderate-severe clinical features and high pre-test probability of disease, and may help for patient follow-up and to identify patients at higher risk of disease worsening. This pictorial essay illustrates typical and uncommon imaging findings of COVID-19 pneumonia and the role of imaging for patient management.

CT imaging findings of abdominopelvic vascular compression syndromes: what the radiologist needs to know.

Abdominopelvic vascular compression syndromes include a variety of uncommon conditions characterized by either extrinsic compression of blood vessels by adjacent anatomical structures (i.e., median arcuate ligament syndrome, nutcracker syndrome, May-Thurner syndrome) or compression of hollow viscera by adjacent vessels (i.e., superior mesenteric artery syndrome, ureteropelvic junction obstruction, ureteral vascular compression syndromes, portal biliopathy). These syndromes can be unexpectedly diagnosed even in asymptomatic patients and the predisposing anatomic conditions can be incidentally discovered on imaging examinations performed for other indications, or they can manifest with atypical abdominal symptoms and acute complications, which may lead to significant morbidity if unrecognized. Although computed tomography (CT) is an accurate noninvasive technique for their detection, the diagnosis remains challenging due to the uncommon clinical presentation and often overlooked imaging features. Dynamic imaging may be performed in order to evaluate patients with inconstant symptoms manifesting in a specific position. The purposes of this paper are to review the CT imaging findings of abdominopelvic vascular compression syndromes, correlating with anatomical variants and to provide key features for the noninvasive imaging diagnosis.

Congenital Cystic Lesions of the Bile Ducts: Imaging-Based Diagnosis.

Congenital cystic lesions of the bile ducts represent a spectrum of liver and biliary system lesions, resulting from abnormal embryologic development of the ductal plate. These disorders include Caroli disease, choledochal cysts, autosomal dominant polycystic liver disease, congenital hepatic fibrosis, and biliary hamartomas. Each disorder carries a peculiar clinical presentation, prognosis, and risk of complications. Knowledge of radiological findings of fibropolycystic liver diseases is crucial for their appropriate detection and for differential diagnosis with other similar hepatic cystic lesions, in order to avoid relevant misdiagnosis. The aim of this review is to provide an illustrative summary of the most relevant imaging findings of these conditions as encountered on ultrasound, computed tomography, and magnetic resonance imaging, and provide pearls for imaging-based differential diagnosis.

Prevalence and clinical significance of incidental findings on multiparametric prostate MRI.

PURPOSE: To assess the prevalence and clinical significance of incidental findings (IFs) detected at multiparametric prostate MRI examination. MATERIALS AND METHODS: Multiparametric prostate MRIs of 647 consecutive patients (mean age 67.1 ± 8.0 years) were retrospectively evaluated by two radiologists recording the presence of all extra-prostatic IFs. Findings were classified as related to or not related to genitourinary system and divided into three classes, according to their clinical significance, as follows: group 1, not significant or scarcely significant; group 2, moderately or potentially significant; and group 3, significant. Differences in distribution of IFs between patients ≤ 65 years old and patients > 65 years old were assessed using Pearson's χ2 or Fisher's exact test. Statistical significance level was set at p < 0.05. RESULTS: Incidental findings (n = 461) were present in 341 (52.7%) patients, while 306 (47.3%) patients did not have any extra-prostatic IF. Overall, IFs were significantly more common in patients > 65 years old (n = 225, 57.0%) compared to patients ≤ 65 years old (n = 116, 46.0%, p = 0.007). There were 139 (30.2%) IFs related to genitourinary system and 322 (69.8%) IFs not related to genitourinary system. Group 3 IFs were almost exclusively present in patients > 65 years old (2.8%, p = 0.034) and included 7 (1.1%) bladder carcinomas, 3 (0.5%) testicle tumors, 2 (0.3%) rectal cancers. Twenty-seven (4.2%) of the 647 patients underwent surgical treatment for IFs not directly related to prostate cancer. CONCLUSION: IFs not related to prostate cancer may be frequently encountered on multiparametric prostate MRI, and they are significantly more common in patients > 65 years old.

Complications of hepatic echinococcosis: multimodality imaging approach.

Hydatid disease is a worldwide zoonosis endemic in many countries. Liver echinococcosis accounts for 60-75% of cases and may be responsible for a wide spectrum of complications in about one third of patients. Some of these complications are potentially life-threatening and require prompt diagnosis and urgent intervention. In this article, we present our experience with common and uncommon complications of hepatic hydatid cysts which include rupture, bacterial superinfection, and mass effect-related complications. Specifically, the aim of this review is to provide key imaging features and diagnostic clues to guide the imaging diagnosis using a multimodality imaging approach, including ultrasound (US), computed tomography (CT), magnetic resonance (MR), and endoscopic retrograde cholangiopancreatography (ERCP).

CT imaging findings of epiploic appendagitis: an unusual cause of abdominal pain.

Epiploic appendagitis is a rare cause of acute abdominal pain, determined by a benign self-limiting inflammation of the epiploic appendages. It may manifest with heterogeneous clinical presentations, mimicking other more severe entities responsible of acute abdominal pain, such as acute diverticulitis or appendicitis. Given its importance as clinical mimicker, imaging plays a crucial role to avoid inaccurate diagnosis that may lead to unnecessary hospitalization, antibiotic therapy, and surgery. CT represents the gold standard technique for the evaluation of patients with indeterminate acute abdominal pain. Imaging findings include the presence of an oval lesion with fat-attenuation surrounded by a thin hyperdense rim on CT ("hyperattenuating ring sign") abutting anteriorly the large bowel, usually associated with inflammation of the adjacent mesentery. A central high-attenuation focus within the fatty lesion ("central dot sign") can sometimes be observed and is indicative of a central thrombosed vein within the inflamed epiploic appendage. Rarely, epiploic appendagitis may be located within a hernia sac or attached to the vermiform appendix. Chronically infarcted epiploic appendage may detach, appearing as an intraperitoneal loose calcified body in the abdominal cavity. In this review, we aim to provide an overview of the clinical presentation and key imaging features that may help the radiologist to make an accurate diagnosis and guide the clinical management of those patients.