Ultrasonography in the Assessment of Tumors of the Cheek: Water Mouth Distension Technique.

PURPOSE: To describe a new B-mode ultrasound examination technique to assess cheek tumors. MATERIALS AND METHODS: 30 cheek oral cavity lesions of different histological types (11 benign and 19 malignant) from 23 patients (11 women and 12 men, 7-82 years old, mean age of 49.5 years) were analyzed. Transcutaneous oral B-mode ultrasound (5-12 MHz transducer) was carried out in two stages. Initially it was performed conventionally with an empty mouth. Next, the patient was asked to keep their oral cavity filled with water (like when using a mouthwash) during imaging for the new test examination technique. The anatomical layers of this region and the characteristics of the tumors were evaluated. Lesions were classified as ill defined, partially defined, or defined. Conventional findings were compared to those of the new technique using the Wilcoxon signed-rank test. Ultrasound results were compared to histological findings analyzed by an independent team. RESULTS: The conventional empty mouth technique was able to confidently define lesion extension in only 6 of the 30 lesions, while the water-filled mouth technique was able to confidently define lesion extension in 29 of the 30 lesions (p<0.00001). CONCLUSION: We present a novel technique that dramatically improves ultrasound staging of cheek oral cavity tumors. In addition to the increase in ultrasound accuracy, this technique does not require any special equipment or extra cost, is very well tolerated by patients, and thus should be considered in the evaluation of every patient undergoing transcutaneous cheek ultrasound for oral cavity lesion characterization.

Focused Assessment with Sonography for Trauma (FAST).

The main cause of death in traumas is hypovolemic shock. Physical examination is limited to detect hemopericardium, hemoperitoneum, and hemopneumothorax. Computed tomography (CT) is the gold standard for traumatic injury evaluation. However, CT is not always available, is more expensive, and there are transportation issues, especially in hemodynamically unstable patients. In this scenario, a rapid, reproducible, portable, and noninvasive method such as ultrasound emerged, directed for detecting hemopericardium, hemoperitoneum, and hemopneumothorax, in a "point of care" modality, known as the focused assessment with sonography for trauma (FAST) protocol. With decades of experience, spread worldwide, and recommended by the most prestigious trauma care guidelines, FAST is a bedside ultrasound to be performed when accessing circulation issues of trauma patients. It is indicated to hemodynamically unstable patients with blunt abdominal trauma, with penetrating trauma of the thoracoabdominal transition (where there is doubt of penetrating the abdominal cavity) and for any patient with the cause of the instability unknown. There are four regions to be examined in the traditional FAST protocol: pericardium (to detect cardiac tamponade), right upper abdominal quadrant, left upper abdominal quadrant, and pelvis (to detect hemoperitoneum). The called extended FAST (e-FAST) protocol also searches the pleural spaces for hemothorax and pneumothorax. It is important to know the false positives and false negatives of the protocol, as well as its limitations. FAST/e-FAST protocol is designed to provide a simple "yes or no" answer regarding the presence of bleeding. It is not intended to quantify the bleeding nor evaluate organ lesions due to its limited accuracy for these purposes. Moreover, the amount of bleeding and/or the identification of organ lesions will not change patient's management: Hemodynamically unstable patients with positive FAST must go to the operating room without delay. CT should be considered for hemodynamically stable patients.

Ultrasound Findings and Laboratory Predictors of Early Mortality in Patients With Severe Yellow Fever.

OBJECTIVE. Yellow fever is a hemorrhagic disease caused by an arbovirus endemic in South America; outbreaks have occurred in recent years. The purpose of this study was to describe abdominal ultrasound findings in patients with severe yellow fever and correlate them with clinical and laboratory data. MATERIALS AND METHODS. A retrospective cohort study was performed between January and April 2018. The subjects were patients admitted to an ICU with polymerase chain reaction-confirmed yellow fever. Bedside sonography was performed within 48 hours of admission. Images were independently analyzed by two board-certified radiologists. Laboratory test samples were collected within 12 hours of image acquisition. Multivariable logistic regression analysis was performed to identify 30-day mortality predictors; p < .05 was considered statistically significant. RESULTS. Forty-six patients (40 [87%] men, six [13%] women; mean age, 47.5 ± 15.2 years) were evaluated with bedside sonography. Laboratory tests showed high serum levels of aspartate aminotransferase (5319 U/L), total bilirubin (6.2 mg/dL), and creati-nine (4.3 mg/dL). Twenty-six (56.5%) patients died within 30 days of admission (median time to death, 5 days [interquartile range, 2-9 days]). The most frequent ultrasound findings were gallbladder wall thickening (80.4%), increased renal cortex echogenicity (71.7%), increased liver parenchyma echogenicity (65.2%), perirenal fluid (52.2%), and ascites (30.4%). Increased renal echogenicity was associated with 30-day mortality (84.6% versus 55.0%; p = .046) and was an independent predictor of this outcome after multivariate analysis (odds ratio, 10.89; p = .048). CONCLUSION. Reproducible abdominal ultrasound findings in patients with severe yellow fever may be associated with severity of disease and prognosis among patients treated in the ICU.

Audiovisual Sexual Stimulation Improves Diagnostic Accuracy of Penile Doppler Ultrasound in Patients With Erectile Dysfunction.

INTRODUCTION: Although penile Doppler ultrasound (PDU) is a useful tool in evaluating erectile dysfunction (ED), an optimal erectile response might be limited because of an increased sympathetic discharge. Audiovisual sexual stimulation (AVSS) has been suggested to help improving PDU performance. AIM: To evaluate the use of AVSS as a tool to improve diagnostic accuracy of PDU studies. METHODS: A total of 40 men (mean age: 61.8 ± 10.2 years) with ED were enrolled. PDU sessions were performed in a randomized fashion as follows: session A under intracavernous injection (ICI) alone and session B under ICI and AVSS with 7-day interval between sessions. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) were measured 5, 10, 15, and 20 minutes after ICI. MAIN OUTCOME MEASURE: Comparisons between PSV, EDV, and RI values were performed with and without AVSS. Univariable and multivariable analyses including clinical and demographic parameters were performed to evaluate predictors of an abnormal PDU. RESULTS: 23 patients performed the first session without AVSS, and 17 performed the first session with AVSS. EDV and RI were better in AVSS session (p = 0.022 and 0.019). PSV was not influenced by AVSS (p = 0.768). The proportion of patients whose diagnosis was changed because of the AVSS was 4 of 40 (10.0%, 95% confidence interval [CI]: 2.8-23.7%). Of 12 patients with venous leak observed on the PDU without AVSS, 3 turned into normal after AVSS (25.0%, 95% CI: 5.5-57.2%). Of 4 men with arterial insufficiency observed on the PDU on ICI alone, 1 became normal after AVSS (25.0%, 95% CI: 0.6-80.6%). International Index of Erectile Function-5 scores were lower in patients with abnormal PDU (6.3 ± 3.3 vs 12.0 ± 5.8, p=0.003). On multivariable analysis, DM and International Index of Erectile Function-5 scores were the only independent predictors of abnormal PDU studies. CLINICAL IMPLICATIONS: False diagnoses of venous leak during PDU with ICI could be a result of an increased adrenergic discharge during the examination. Routine AVSS may be helpful to avoid error in diagnosis. STRENGTH & LIMITATIONS: The study has randomized the use of AVSS in different session orders. Only one previously published study has used this strategy to control the accommodation effect in repeat studies, a common source of bias in the PDU literature. The main limitation is the absence of a rigidity assessment and a redosing protocol. CONCLUSION: Adding AVSS during PDU improves ICI response and may help clinicians evaluate penile hemodynamics more accurately. Carneiro F, Nascimento B, Miranda EP, et al. Audiovisual Sexual Stimulation Improves Diagnostic Accuracy of Penile Doppler Ultrasound in Patients With Erectile Dysfunction. J Sex Med 2020;17:249-256.

Laser Ablation of Benign Thyroid Nodules: A Prospective Pilot Study With a Preliminary Analysis of the Employed Energy.

BACKGROUND AND OBJECTIVES: To assess the effectiveness of ultrasound (US)-guided laser ablation of benign thyroid nodules (TNs) under different amounts of applied energy. STUDY DESIGN/MATERIALS AND METHODS: Thirty-four euthyroid patients with 5-18 ml TNs were enrolled: 21 (laser ablation) and 13 (clinical follow up) patients with a mean age of 56.2 ± 12.0 and 54.7 ± 14.7 years, respectively. The laser ablation protocol used a 1.064 mm wavelength diode laser source; 3.5 W output power; 1,100-1,500 J and 5-8 min/illumination; and one or two fibers/session. Clinical, laboratory, and US data were obtained immediately before treatment and at 6 and 12 months follow-up and were analyzed by Student's t test and Fisher's exact test. Low- and high-energy subgroups were subsequently defined, and the receiver operating characteristic (ROC) curves were calculated. RESULTS: Laser ablation follow-up showed an overall nodule volume reduction of more than 50%; improvement of symptoms and cosmetic complaints (P = 0.001); and stable laboratory data compared with the baseline and control groups. Minor complications were 9.5% ( n = 2). One or two fibers/session resulted in a similar nodule volume reduction among 10-18 ml nodules. Analysis of the applied energy suggested a 398.8 J/ml inferior cutoff (ROC curve: 0.889 sensitivity; 0.545 specificity) for the high-energy subgroup ( n = 14, mean 599.9 ± 136.5 J/ml) to reduce the nodule volume over time (-55.1% vs. -58.4%, P = 0.55). The low-energy subgroup ( n = 7, mean 240.2 ± 74.6 J/ml) did not show a persistent volume reduction ( P < 0.05) from the 6- to 12-month follow-ups (-56.6% vs. -53.7%). CONCLUSIONS: Laser ablation of benign TNs achieved technique efficacy at 12 months posttreatment, with clinical improvement and few minor side effects. A single fiber in a single session with a high deployed energy (>398.8 J/ml) may be associated with improved results, a finding to be confirmed with a larger series. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Guidelines and Good Clinical Practice Recommendations for Contrast Enhanced Ultrasound (CEUS) in the Liver - Update 2020 - WFUMB in Cooperation with EFSUMB, AFSUMB, AIUM, and FLAUS.

The present, updated document describes the fourth iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS), first initiated in 2004 by the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB). The previous updated editions of the guidelines reflected changes in the available contrast agents and updated the guidelines not only for hepatic but also for non-hepatic applications.The 2012 guideline requires updating as previously the differences of the contrast agents were not precisely described and the differences in contrast phases as well as handling were not clearly indicated. In addition, more evidence has been published for all contrast agents. The update also reflects the most recent developments in contrast agents, including the United States Food and Drug Administration (FDA) approval as well as the extensive Asian experience, to produce a truly international perspective.These guidelines and recommendations provide general advice on the use of ultrasound contrast agents (UCA) and are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis to improve the management of patients.

Volumetry and biomechanical parameters detected by 3D and 2D ultrasound in patients with and without an abdominal aortic aneurysm.

The objective was to demonstrate the ability of ultrasound (US) with 3D properties to evaluate volumetry and biomechanical parameters of the aorta in patients with and without abdominal aortic aneurysm (AAA). Thirty-one patients with normal aortas (group 1), 46 patients with AAA measuring 3.0-5.5 cm (group 2) and 31 patients with AAA ⩾ 5.5 cm (group 3) underwent a 2D/3D-US examination of the infra-renal aorta, and the images were post-processed prior to being analyzed. In the maximum diameter, the global circumferential strain and the global maximum rotation assessed by 2D speckle-tracking algorithms were compared among the three groups. The volumetry data obtained using 3D-US from 40 AAA patients were compared with the volumetry data obtained by a contemporary computed tomography (CT) scan. The median global circumferential strain was 2.0% (interquartile range (IR): 1.0-3.0), 1.0% (IR: 1.0-2.0) and 1.0% (IR: 1.0-1.75) in groups 1, 2 and 3, respectively (p < 0.001). The median global maximum rotation decreased progressively from group 1 to group 3 (1.38º (IR: 0.77-2.13), 0.80º (IR: 0.57-1.0) and 0.50º (IR: 0.31-0.75), p < 0.001). AAA volume estimations by 3D-US correlated well with CT (R(2) = 0.76). In conclusion, US with 3D properties is non-invasive and has the potential to evaluate volumetry and biomechanical characteristics of AAA.

Vesicoureteral reflux by contrast ultrasound, comparison with voiding and retrograde urethrocystography: A prospective accuracy study.

INTRODUCTION: Diagnosis of vesicoureteral reflux (VUR) plays an important role in the management and follow-up of children presenting with urinary tract infection. This study compared voiding uronosography (VUS) as a diagnostic method for the diagnosis of VUR with the "gold standard", voiding or micturating cystourethrography (MCU). The objective of the study is not only to compare the effectiveness of both methods, but also to assess the feasibility of implementing VUS technically and economically in a large tertiary radiology center in South America. MATERIALS AND METHOD: This was a prospective accuracy study that include 41 patients (a total of 85 ureteral units) aged between 1 month and 16 years. VUS was performed in an alternative form as regular MCU, by injecting microbubble contrast solution (SonoVue©) into the bladder through an intermittent catheter and evaluating the presence of reflux with ultrasound. MCU was always performed immediately after VUS. One pediatric radiologist evaluated all VUS exams, while a second independent pediatric radiologist evaluated all MCU exams, with both blinded to each other's assessments. RESULTS: Comparing VUS with MCU in the diagnosis of VUR, we observed a sensitivity of 92.3 % (95 % CI 74.9-99.1 %), specificity of 98.3 % (95 % CI 90.9-100 %), positive predictive value of 96.0 % (95 % CI 79.6-99.9 %), negative predictive value of 96.7 % (95 % CI 88.5-99.6 %) and a Kappa of 0.916 (0.822-1.000). When comparing the VUR grading between VUS and MCU the agreement between the two methods was high with a Kendall's Tau-b > 0.9. VUS failed to diagnose two grade 1 VUR reflux cases in teenagers while diagnosing one grade 4 VUR in a very dilated kidney-ureter unit, which was missed on MCU. VUS and MCU had similar costs when considering the price of the ultrasound contrast agent. DISCUSSION: VUS is a reliable alternative method to MCU for the diagnosis of VUR with the advantages of not exposing the child to ionizing radiation and potentially being more accessible due to the greater availability of ultrasound equipment. Limitations to this study include the usage of a single ultrasound equipment, which limits its generalizability and not evaluating the interobserver variability. CONCLUSION: Consideration should be given to implementing VUS for the diagnosis of VUR, particularly in centers without fluoroscopy equipment available, since the exam's performance and cost are comparable to those of the MCU.

Thyroid disturbance related to chronic hepatitis C infection: role of CXCL10.

Association between autoimmune thyroid diseases (AITD) and hepatitis C is controversial, but may occur or worsen during alpha-interferon treatment. The mechanism responsible for autoimmune diseases in infected patients has not been fully elucidated. This study aims to evaluate the frequency of AITD in chronic hepatitis C and the association of chemokine (CXC motif) ligand 10 (CXCL10) and AITD. One hundred and three patients with chronic hepatitis C and 96 controls were prospectively selected to clinical, hormonal, thyroid autoimmunity and ultrasound exams, besides thyroxine-binding globulin (TBG) and CXCL10 measurements and hepatic biopsies. The frequency of AITD among infected subjects was similar to controls. TT3 and TT4 distributions were right shifted, as was TBG, which correlated to both of them. Thyroid heterogeneity and hypoechogenicity were associated with AITD. Increased vascularization was more prevalent in chronic hepatitis C.CXCL10 was higher in infected patients (p=0.007) but was not related to thyroid dysfunction. Increase in CXCL10 levels were consistent with hepatic necroinflammatory activity (p=0.011). In summary, no association was found between chronic hepatitis C and AITD. Infected subjects had higher TT3 and TT4 which were correlated to TBG. Increased CXCL10 was not associated to thyroid dysfunction in HCV-infected population.

Increased prevalence of simple renal cysts in patients with gout.

The aim of this study was to determine the prevalence of simple renal cysts in gout patients and evaluate associated risk factors for its development. Hundred and forty-six patients followed at our outpatient Gout Unit and 47 sex- and age-matched healthy kidney donors who had undergone routine renal ultrasonography, using a static gray scale and real-time B-mode units with a 3.5- or 5.0-MHz transducer, were evaluated for the presence of renal cysts. Demographic and clinical characteristics of gout patients were evaluated considering possible risk factors for the occurrence of simple renal cysts such as age, male gender, hypertension, and renal impairment. The prevalence of simple renal cyst was 26.0 % in gout patients and 10.6 % in control group (P = 0.045). Gout patients with simple renal cysts presented less renal lithiasis than those without this complication (5.2 vs 25.9 %; P = 0.003) in spite of an overall higher frequency of renal stones in gout patients compared to control group (20.5 vs. 6.3 %, P = 0.025). The presence of simple renal cyst in gout was not associated with previously reported factors such as age (P = 0.296), male predominance (P = 0.688), hypertension (P = 0.314), and renal impairment (P = 254). Moreover, no association with disease duration (P = 0.843) or tophi (P = 0.616) was observed. In conclusion, gout patients have an increased prevalence of simple renal cysts associated with a lower occurrence of nephrolithiasis. Whether renal cysts have any protective effect in the development of nephrolithiasis in gout remains to be determined.

Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial.

Chronic autoimmune thyroiditis (CAT) is the most common cause of acquired hypothyroidism, which requires lifelong levothyroxine replacement therapy. Currently, no effective therapy is available for CAT. Thus, the objective of this study was to evaluate the efficacy of low-level laser therapy (LLLT) in patients with CAT-induced hypothyroidism by testing thyroid function, thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb), and ultrasonographic echogenicity. A randomized, placebo-controlled trial with a 9-month follow-up was conducted from 2006 to 2009. Forty-three patients with a history of levothyroxine therapy for CAT-induced hypothyroidism were randomly assigned to receive either 10 sessions of LLLT (830 nm, output power of 50 mW, and fluence of 707 J/cm(2); L group, n=23) or 10 sessions of a placebo treatment (P group, n=20). The levothyroxine was suspended 30 days after the LLLT or placebo procedures. Thyroid function was estimated by the levothyroxine dose required to achieve normal concentrations of T3, T4, free-T4 (fT4), and thyrotropin after 9 months of postlevothyroxine withdrawal. Autoimmunity was assessed by measuring the TPOAb and TgAb levels. A quantitative computerized echogenicity analysis was performed pre- and 30 days postintervention. The results showed a significant difference in the mean levothyroxine dose required to treat the hypothyroidism between the L group (38.59 ± 20.22 µg/day) and the P group (106.88 ± 22.90 µg/day, P<0.001). Lower TPOAb (P=0.043) and greater echogenicity (P<0.001) were also noted in the L group. No TgAb difference was observed. These findings suggest that LLLT was effective at improving thyroid function, promoting reduced TPOAb-mediated autoimmunity and increasing thyroid echogenicity in patients with CAT hypothyroidism.

Ultrasonography on the non-living. Current approaches.

The vast majority of clinicians associate diagnostic ultrasound with a tool that is designed for the living patient. However, it is of course possible to apply this imaging technology to evaluate the recently deceased patient for postmortem diagnosis, or even just examine postmortem tissue. We describe several cases in which ultrasound-enabled providers obtain answers in postmortem examinations and discuss potential future strategies and applications. In addition, we will also illustrate the use of sonography in minimally invasive post-mortem tissue sampling (MITS), an approach that can be used in post-mortem minimally invasive autopsies as well as for establishing ultrasound diagnostic parameters in new medical fields such as periodontal and dental implant specialties.

Ultrasound in cervical traumatic neuromas after neck dissection in thyroid carcinoma patients: descriptive analysis and diagnostic accuracy.

Objective: Cervical traumatic neuromas (CTNs) may appear after lateral neck dissection for metastatic thyroid carcinoma. If they are misdiagnosed as metastatic lymph nodes (LNs) in follow-up neck ultrasound (US), unnecessary and uncomfortable fine-needle aspiration biopsy are indicated. The present study aimed to describe US features of CTNs and to assess the US performance in distinguishing CTNs from abnormal LNs. Subjects and methods: Retrospective evaluation of neck US images of 206 consecutive patients who had lateral neck dissection as a part of thyroid cancer treatment to assess CTN´s US features. Diagnostic accuracy study to evaluate US performance in distinguishing CTNs from abnormal LNs was performed. Results: Eight-six lateral neck nodules were selected for analysis: 38 CTNs and 48 abnormal LNs. CTNs with diagnostic cytology were predominantly hypoechogenic (100% vs. 45%; P = 0.008) and had shorter diameters than inconclusive cytology CTNs: short axis (0.39 cm vs. 0.50 cm; P = 0.03) and long axis (1.64 cm vs. 2.35 cm; P = 0.021). The US features with the best accuracy to distinguish CTNs from abnormal LNs were continuity with a nervous structure, hypoechogenic internal lines, short/long axis ratio ≤ 0.42, absent Doppler vascularization, fusiform morphology, and short axis ≤ 0.48 cm. Conclusion: US is a very useful method for assessing CTNs, with good performance in distinguishing CTNs from abnormal LNs.

Contrast-enhanced ultrasonography for the evaluation of malignant focal liver lesions.

In this review, the authors address the analysis of different types of malignant focal liver lesions (FLLs) using contrast-enhanced ultrasonography (CEUS). The specific enhancing patterns of hepatocellular carcinoma, cholangiocarcinoma, and metastases are discussed and exemplified with images. In addition, the use of CEUS in malignant portal vein thrombosis is discussed. The advantages and limitations of CEUS for the analysis of malignant FLLs are also discussed.

How to Identify Cervical Traumatic Neuromas in the Post-operative Neck Dissection: Brief Review of the Cervical Plexus Ultrasound.

Cervical traumatic neuromas (CTNs) are a non-neoplastic hyperplasia of damaged nerves and may be misinterpreted as metastatic lymph nodes during cervical ultrasound of patients with thyroid cancer after lateral neck dissection, resulting in unnecessary and painful fin-needle aspiration biopsy. The anatomy of the cervical plexus is challenging, and the correct identification and recognition of its neural roots and branches on ultrasound are key to the correct CTN diagnosis. This review outlines the US technique used to characterize CTNs in 10 standardized steps and describes the sonographic features of the cervical plexus, to assist the radiologist in the recognition of CTNs and their differentiation from lymph node metastases.

Contrast-Enhanced Ultrasound Features of Histopathologically Proven Hepatocellular Carcinoma in the Non-cirrhotic Liver: A Multicenter Study.

Current literature on the role of contrast-enhanced ultrasound (CEUS) in the diagnosis of hepatocellular carcinoma (HCC) in non-cirrhotic patients is limited. The aim of this retrospective multicenter study was to analyze CEUS features of histologically proven HCC in patients with non-cirrhotic liver. In this multicenter study, 96 patients from eight medical institutions with histologically proven HCC lesions in non-cirrhotic liver were retrospectively reviewed regarding SonoVue-enhanced CEUS features. Two ultrasound experts assessed the CEUS enhancement pattern and came to a consensus using the World Federation of Societies for Ultrasound in Medicine and Biology guideline criteria. The mean size of HCC lesions included was 60.3 ± 37.8 mm (mean ± standard deviation). Most of the lesions were heterogeneous but predominantly hypo-echoic on B-mode ultrasound (64.5%, 62/96), with ill-defined margins and irregular shapes. During the arterial phase of CEUS, most of the HCC lesions in non-cirrhotic liver exhibited heterogeneous hyperenhancement (78.1%, 75/96) compared with the surrounding liver parenchyma. Almost 30% of HCC lesions (28.1%, 27/96) exhibited early wash-out (<60 s). All lesions exhibited wash-out and hypo-enhancement in the late phase. CEUS features of HCC lesions in non-cirrhotic patients typically include hyperenhancement in the arterial phase and relatively rapid wash-out in the portal venous phase, which is different from HCC in cirrhotic livers and more similar to liver metastasis.

Hepatocellular carcinoma in the non-cirrhotic liver.

Liver cirrhosis is an established high-risk factor for HCC and the majority of patients diagnosed with HCC have cirrhosis. However, HCC also arises in non-cirrhotic livers in approximately 20 %of all cases. HCC in non-cirrhotic patients is often clinically silent and surveillance is usually not recommended. HCC is often diagnosed at an advanced stage in these patients. Current information about HCC in patients with non-cirrhotic liver is limited. Here we review the current knowledge on epidemiology, clinical features and imaging features of those patiens.