Sonography of the pleura. / Sonografie der Pleura.

The CME review presented here is intended to explain the significance of pleural sonography to the interested reader and to provide information on its application. At the beginning of sonography in the 80 s of the 20th centuries, with the possible resolution of the devices at that time, the pleura could only be perceived as a white line. Due to the high impedance differences, the pleura can be delineated particularly well. With the increasing high-resolution devices of more than 10 MHz, even a normal pleura with a thickness of 0.2 mm can be assessed. This article explains the special features of the examination technique with knowledge of the pre-test probability and describes the indications for pleural sonography. Pleural sonography has a high value in emergency and intensive care medicine, preclinical, outpatient and inpatient, in the general practitioner as well as in the specialist practice of pneumologists. The special features in childhood (pediatrics) as well as in geriatrics are presented. The recognition of a pneumothorax even in difficult situations as well as the assessment of pleural effusion are explained. With the high-resolution technology, both the pleura itself and small subpleural consolidations can be assessed and used diagnostically. Both the direct and indirect sonographic signs and accompanying symptoms are described, and the concrete clinical significance of sonography is presented. The significance and criteria of conventional brightness-encoded B-scan, colour Doppler sonography (CDS) with or without spectral analysis of the Doppler signal (SDS) and contrast medium ultrasound (CEUS) are outlined. Elastography and ultrasound-guided interventions are also mentioned. A related further paper deals with the diseases of the lung parenchyma and another paper with the diseases of the thoracic wall, diaphragm and mediastinum.

The value of contrast-enhanced ultrasound in percutaneous biopsy of retroperitoneal masses.

PURPOSE: To evaluate the diagnostic yield of contrast-enhanced ultrasound (CEUS)-guided biopsy of retroperitoneal masses (RMs). MATERIALS AND METHODS: Between 2006 and 2023, 87 patients presented at our US center for biopsy of an RM. In all biopsies, CEUS was performed prior to the intervention. The technical success rate of biopsy, the presence of diagnostic tissue in solid tumor biopsy samples, the accuracy of the biopsy and the occurrence of post-interventional complications were evaluated. RESULTS: A US-guided biopsy could be conducted in 84/87 cases (96.6%). In 3/87 cases (3.4%), US-guided biopsy was impossible because the planned needle path was obstructed by vital structures. Of 84 lesions, 80 (95.2%) were solid lesions, and 4 (4.8%) were lesions containing fluid. In all solid tumors, 80/80 (100%), diagnostic vital tissue was successfully obtained. CEUS-guided biopsy showed a sensitivity of 93.2%, a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 72.2%, and a diagnostic accuracy of 94.2% for the differentiation between malignant and benign RMs. In one of the 84 cases (1.2%), there was a complication of postinterventional abdominal pain. CONCLUSION: Percutaneous CEUS-guided biopsy is a safe procedure with a high diagnostic yield and a low complication rate.

Value of contrast-enhanced ultrasound for vascular diseases of the liver - current indications and open questions.

Contrast-enhanced ultrasonography (CEUS) is a widely available and well-tolerated technique that can expand the diagnosis of a variety of vascular liver diseases. This paper presents an overview of the current possibilities of the use of CEUS in vascular liver diseases. Particularly where Doppler sonography has technical limitations, CEUS provides additional opportunities to visualize vascular thrombosis and other obstructions restricting blood flow. When CT or MRI contrast agents cannot be used because of severe allergy or renal insufficiency, CEUS can be a valuable diagnostic alternative and has demonstrated comparable diagnostic performance in at least some vascular liver diseases, such as portal vein thrombosis. In addition, CEUS works without radiation and, therefore, might be particularly suitable for young patients and children. This may be useful, for example, in congenital disorders such as persistent umbilical vein or preduodenal portal vein. Vascular liver disease is rare and comprehensive data are still lacking, but the available literature provides promising insights into potential new ways to study vascular liver disease. Although most studies are based on small sample sizes or even case reports, the high diagnostic utility is undisputed.

Prevalence of benign focal liver lesions and non-hepatocellular carcinoma malignant lesions in liver cirrhosis.

Liver cirrhosis is associated with an increased risk of developing hepatocellular carcinoma (HCC). However, other benign and malignant liver lesions may co-exist or may be the only focal liver lesion (FLL) detected. Compared to HCC, comparatively little is known about the frequency and natural history of benign FLL in patients with established liver cirrhosis.This review analyses the prevalence and frequency of benign and malignant FLL others than hepatocellular carcinoma (HCC) in liver cirrhosis including imaging and autopsy studies. Understanding these data should be helpful in avoiding misdiagnoses.

Ultrasound Elastography for Characterization of Focal Liver Lesions.

Focal liver lesions (FLL) are typically detected by conventional ultrasound or other imaging modalities. After the detection of FLL, further characterization is essential, and this can be done by contrast-enhanced imaging techniques, e.g., contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) or by means of biopsy with histological evaluation. Elastographic techniques are nowadays integrated into high-end ultrasound systems and their value for the detection of severe liver fibrosis and cirrhosis has been shown in studies and meta-analyses. The use of an ultrasound elastographic technique for the differentiation of malignant and benign liver tumors is less well-established. This review summarizes the current data on utility and performance of ultrasound elastography for the characterization of FLL.

[Hyposplenism, an underrecognised immune diffeciency: Is sonography helpful?] / "Hyposplenie", eine weitgehend unerkannte Immunschwäche: Ist die Sonografie hilfreich?

The immunodeficiency syndrome of functional hyposplenia/asplenia is frequently unrecognized. The gold standard procedure for the diagnosis of this disease is technetium-99m scintigraphy of heat-denatured erythrocytes and the detection of pitted erythrocytes or Howell-Jolly bodies. Initial work suggests that this clinical presentation is associated with a small spleen. The aim of this review is to describe the value of B-mode and contrast-enhanced ultrasound in the identification of immunodeficiency caused by functional hyposplenism.

Evaluation and Classification of Incidentally Detected Splenic Lesions Based on B-Mode and Contrast-Enhanced Ultrasound.

PURPOSE: To evaluate B-mode ultrasound (B-US) and contrast-enhanced ultrasound (CEUS) patterns of focal splenic incidentalomas (FSIs), and to correlate ultrasound patterns with benignity and malignancy via histologic examination and/or the clinical course. MATERIALS AND METHODS: Between 2004 and 2021, 139 consecutive patients with an FSI detected by B-US were investigated additionally with CEUS. On CEUS, the arterial enhancement (AE) of the FSI (hyperenhancement, isoenhancement, hypoenhancement, and absent enhancement) was analyzed. Subsequently, the malignancy rate according to different B-US echo patterns and CEUS perfusion patterns was determined. RESULTS: The final diagnosis of FSI was malignant in 9/139 (6.5%) and benign in 130/139 (93.5%) cases. The hypoechoic and hyperechoic lesions on B-US with arterial hyperenhancement on CEUS and the echogenic cystic or complex lesions on B-US with predominantly absent enhancement on CEUS were benign in 54/54 (100%) cases. 6/37 (16.2%) hypoechoic lesions on B-US with arterial hypo-/isoenhancement on CEUS and 3/48 (6.3%) of hyperechoic lesions on B-US with an arterial hypo-/isoenhancement on CEUS were malignant. CONCLUSION: Based on these results, FSIs reveal different malignancy rates depending on the B-US und CEUS patterns, and classification according to these B-US and CEUS patterns may be helpful in further evaluation of an FSI.

Ultrasound of the lung. / Lungensonografie.

The CME review is intended to explain and discuss the clinical value of lung ultrasound but also to enable a pragmatically oriented approach by analyzing the clinical aspect. This includes knowledge of the pre-test probability, the acuteness of the disease, the current clinical situation, detection and/or characterization, initial diagnosis or follow up assessment and the peculiarities of exclusion diagnosis. Diseases of the pleura and lungs are described using these criteria with their direct and indirect sonographic signs and the specific clinical significance of ultrasound findings. The importance and criteria of conventional B-mode, color Doppler ultrasound with or without spectral analysis of the Doppler signal and contrast-enhanced ultrasound are discussed as well.

B-Mode Ultrasound and Contrast-Enhanced Ultrasound for the Detection of Splenic Involvement in Hodgkin Lymphoma: A Retrospective Analysis of 112 Patients.

PURPOSE: To assess splenic involvement using B-mode ultrasound (US) and contrast-enhanced ultrasound (CEUS) compared with standard imaging with contrast-enhanced computerized tomography (CT) / 18-fluorodeoxyglucose positron-emission tomography (PET-CT) in patients with Hodgkin lymphoma. MATERIALS AND METHODS: Imaging data from 112 patients from 12/2003 to 10/2022 with histologically confirmed Hodgkin lymphoma during staging or relapse were analyzed for splenic lymphoma involvement. In all patients, standard imaging (CT/PET-CT), along with B-mode US and CEUS examinations, was performed. Evidence of focal splenic lesions (FSLs) found by imaging procedures was suggestive of splenic involvement. Follow-up imaging was performed in each patient after treatment, and treatment response indicated definitive splenic involvement. RESULTS: 40 patients (35.7%) were identified by imaging modalities as having splenic involvement, which was confirmed by response during follow-up. Standard CT/PET-CT imaging detected splenic involvement in 36/112 patients (32.1%). FSLs were detected with B-mode US in 38 patients (33.9%) and CEUS in 36 patients (32.1%). The sensitivity of standard imaging, B-mode US, and CEUS was 90%, 95%, and 90%, respectively. CONCLUSION: B-mode US examination is a diagnostic method used in addition to standard imaging for the detection of splenic involvement in Hodgkin lymphoma. CEUS does not provide additional benefit compared to B-mode US and the standard reference procedure.

Contrast-Enhanced Ultrasound for Evaluation of Pleural Effusion: A Pictorial Essay.

B-mode ultrasound (B-US) is the standard imaging modality to evaluate pleural effusion. The value of B-US for assessing the malignancy of a pleural effusion (PE) is limited. For this purpose, computed tomography (CT) and thoracoscopy are the methods of choice to evaluate an effusion. The aim of this Pictorial Essay is to demonstrate contrast-enhanced ultrasound (CEUS) as a method in addition to B-US and CT for the evaluation of PE taking into account the clinical background. The characteristic patterns of pleural pathologies, effusion morphology, and associated lung parenchymal consolidations are presented.

Peripheral Pulmonary Lesions in Confirmed Pulmonary Arterial Embolism: Follow-up Study of B-Mode Ultrasound and of Perfusion Patterns Using Contrast-Enhanced Ultrasound (CEUS).

PURPOSE: This retrospective study aimed to describe the B-mode lung ultrasound (B-LUS) and contrast-enhanced ultrasound (CEUS) follow-up patterns of peripheral pulmonary lesions (PPLs) in patients with confirmed pulmonary embolism (PE). PATIENTS AND METHODS: Data from 27 patients with a confirmed diagnosis of PE and PPLs over 5 mm from October 2009 to November 2018 were included retrospectively in the study. The inclusion criteria were performance of a baseline CEUS examination, a short-term B-LUS and CEUS follow-up, and a long-term B-LUS follow-up of PPLs. The homogeneity of enhancement of PPLs (homogeneous/inhomogeneous/absent) on CEUS and the presence and size of PPLs on B-LUS were evaluated. RESULTS: A total of n = 25/27 (92.6%) lesions showed absent or inhomogeneous enhancement during baseline examination or short-term follow-up, indicating impaired perfusion. On short-term CEUS follow-up, 9/27 cases (33.3%) showed a pattern shift. On B-LUS long-term follow-up, 26/27 lesions (96.3%) were detectable for an average of 10 weeks (range 3-32 weeks). The size of reference lesions was significantly reduced at the time of the final follow-up examination (P < .05). CONCLUSION: B-LUS follow-up showed that, in patients with confirmed PE, PPLs had a delayed regression. On CEUS follow-up examination, various perfusion patterns of PPLs were observed, indicating the different ages and the variable reparative processes of pulmonary infarction. In PPLs independent of the underlying signs and symptoms, follow-up B-LUS and CEUS examinations may be helpful for a possible retrospective diagnosis of peripheral pulmonary infarction suggestive of PE.

Assessment of Early Therapy Response of Non-Hodgkin's and Hodgkin's Lymphoma Using B-Mode Ultrasound and Dynamic Contrast-Enhanced Ultrasound.

OBJECTIVES: Here we asked, whether contrast enhanced ultrasound (CEUS) enables to judge early treatment response in malignant lymphoma as a potential guidance for further treatment. METHODS: From May 2017 to May 2018, 21 patients with histologically confirmed diagnosis of lymphoma were examined by B-mode ultrasound (B-US) and CEUS at fixed early time points after commencing therapy (days [d] 0, 15 and 30 after therapy start) and contrast enhancement patterns in target lymphoma lesions were quantified using Bracco-VUE Box® (DCE-US). To estimate the potential value of CEUS-enhancement patterns for early response prediction, patients were grouped according to their best achieved actual response into complete remission (CR) patients, partial remission (PR) patients or progressive disease (PD) patients. RESULTS: Between d0, d15 and d30, CR-patients showed a median lymphoma shrinking by 34% in B-US. PD-patients experienced a median lymphoma size reduction by 44% on day 15, but lymphoma mass again increased by 20% between d15 and d30. In contrast, the median CEUS enhancement intensity, as assessed by the area under the curve (AUC) was increasing at d15 in CR and PD patients (CR to 152%, PD: to 126%), but decreased at d30 to 14% in CR patients and 22% in PD patients. CONCLUSIONS: While early response assessment using B-US might be useful to predict treatment response in lymphoma, CEUS and DCE-US-although often feasible-do not provide additional value in this regard.

Perfusion Patterns of Peripheral Pulmonary Granulomatous Lesions Using Contrast-Enhanced Ultrasound (CEUS) and Their Correlation with Immunohistochemically Detected Vascularization Patterns.

PURPOSE: To describe the perfusion patterns of peripheral pulmonary granulomatous lesions (PPGLs) by contrast-enhanced ultrasound (CEUS) and their correlation with vascularization patterns (VPs) represented by immunohistochemical (CD34) endothelial staining. PATIENTS AND METHODS: From January 2007 until September 2020, 10 consecutive patients with histologically confirmed PPGLs were investigated by CEUS. The time to enhancement, classified as early pulmonary-arterial (PA) pattern of enhancement versus delayed bronchial-arterial (BA) pattern of enhancement, the extent of enhancement, classified as marked or reduced, the homogeneity of enhancement, classified as homogeneous or inhomogeneous, and the decrease of enhancement, classified as rapid washout (<120 seconds) or a late washout (≥120 seconds), were analyzed retrospectively. Furthermore, the tissue samples from the study patients and as a control group, 10 samples of normal lung tissue obtained by autopsy, and 10 samples of lung tissue with acute pneumonia obtained by autopsy were immunohistochemically stained with CD34 antibody. The presence of avascular areas (AAs) and the VPs were evaluated in all tissue samples. RESULTS: On CEUS, all PPGLs showed a reduced inhomogeneous BA pattern of enhancement and a rapid washout (<120 seconds). On CD34 staining, all PPGLs showed central AAs in granulomas and a chaotic VP similar to angiogenesis in lung tumors. The lung tissue in control groups revealed on CD34 staining a regular alveolar VP. CONCLUSION: The PPGLs on CEUS show an identical perfusion pattern similar to those of malignant lesions. Furthermore, for the first time, neoangiogenesis was demonstrated as a histopathological correlate to BA pattern of enhancement on CEUS.

The Value of Lung Ultrasound to Detect the Early Pleural and Pulmonary Pathologies in Nonhospitalized COVID-19-Suspected Cases in a Population With a Low Prevalence of COVID-19 Infection: A Prospective Study in 297 Subjects.

OBJECTIVES: This prospective study aimed to evaluate the value of B-mode lung ultrasound (LUS) for the early diagnosis of coronavirus disease 2019 (COVID-19) infection in nonhospitalized COVID-19 suspected cases in a population with a low prevalence of disease. METHODS: From April 2020 to June 2020, in an ambulatory testing center for COVID-19-suspected cases, 297 subjects were examined by LUS before a nasopharyngeal swab was taken for a reverse transcription polymerase chain reaction (RT-PCR) test. The following LUS findings were defined as pathological ultrasound findings and were analyzed: the presence of 1) pleural effusion, 2) B-lines, 3) fragmented visceral pleura, 4) consolidation, and 5) air bronchogram in the consolidation. The LUS findings were compared with the RT-PCR test results. RESULTS: The result of the RT-PCR test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was positive in 11 and negative in 286 subjects, and the prevalence of COVID-19 infection in the study participants was 3.7%. On LUS, a pathological finding could be detected in 56/297 (18.9%) study participants. The LUS revealed a sensitivity of 27.3%, a specificity of 81.5%, a positive predictive value of 5.4%, a negative predictive value of 96.7%, and a diagnostic accuracy of 79.9% for the identification of COVID-19 infection. CONCLUSIONS: For the identification of COVID-19 infection, LUS is highly sensitive to the patient spectrum and to the prevalence of the disease. Due to the low diagnostic performance in nonhospitalized COVID-19 cases in low-prevalence areas, LUS cannot be considered to be an adequate method for making a diagnosis in this group.

Frequency of synchronous malignant liver lesions initially detected by ultrasound in patients with newly diagnosed underlying non-hematologic malignant disease: a retrospective study in 434 patients.

INTRODUCTION: This study described the frequency of malignant synchronous focal liver lesions (FLLs) in patients with newly diagnosed non-hematologic malignant disease. METHODS: From June 2013 to January 2017, 434 patients with synchronous FLLs and newly diagnosed underlying malignant disease were included in the study. The diagnosis of the FLLs was made by histology and/or contrast-enhanced imaging. The final medical report was used for analysis in the study. RESULTS: Of the 434 liver lesions, 258 (59.4%) were malignant and 176 (40.6%) benign. All malignant lesions were metastases. The benign liver lesions were comprised of 93 cysts (21.4%), 52 hemangiomas (12.0%), 20 focal fatty sparing (4.6%), 4 focal nodular hyperplasia (0.9%), 3 unspecified benign lesions (0.7%), 2 regenerative nodules (0.5%), 1 calcification (0.2%), and 1 adenoma (0.2%). Diseases with the highest percentage frequency of synchronous malignant FLLs were cholangiocarcinoma with 86.7%, neuroendocrine tumor with 72.7%, and pancreatic carcinoma with 72.0%. Gastric carcinoma (33.3%), breast carcinoma (44.4%), and urothelial cell carcinoma (45.5%) were the diseases with the lowest percentage frequency of synchronous malignant FLLs. CONCLUSION: In total, the frequency of malignant synchronous FLLs in newly diagnosed non-hematologic malignant disease was 59.4%. In particular, cholangiocarcinoma, neuroendocrine tumor, and pancreatic carcinoma were the diseases with the highest rate of synchronous malignant FLLs.

Contrast-enhanced ultrasound is helpful for differentiating benign from malignant parietal pleural lesions.

INTRODUCTION: To describe the value of contrast-enhanced ultrasound (CEUS) for the differentiation of malignant from benign parietal pleural lesions (PPLs). MATERIALS AND METHODS: From November 2005 to June 2019, 63 patients with histologically/cytologically confirmed PPLs were investigated by CEUS. On CEUS, the extent of enhancement (EE; marked or reduced/absent) and the homogeneity of enhancement (HE; homogeneous or inhomogeneous) were analyzed retrospectively. RESULTS: In total, 24/63 lesions were benign, and 39/63 lesions were malignant. On CEUS, 11/24 benign and 36/39 malignant lesions showed a marked enhancement. A marked enhancement was significantly more frequently associated with malignancy compared with benign lesions (p < 0.001). In five cases, due to the absence of enhancement, it was not possible to determine the HE. In the remaining cases, 9/20 benign and 19/38 malignant lesions showed an inhomogeneous enhancement (p = 0.79). CONCLUSION: On CEUS, marked enhancement was significantly more frequently associated with malignant compared with benign lesions. However, some benign lesions, such as chronic inflammatory processes, may also show a marked enhancement. Therefore, the interpretation of perfusion patterns in these lesions must always take into account the clinical background of the patient.

Perfusion Patterns of Peripheral Pulmonary Lesions in COVID-19 Patients Using Contrast-Enhanced Ultrasound (CEUS): A Case Series.

PURPOSE: To describe perfusion patterns of peripheral pulmonary lesions (PPLs) in COVID-19 patients using contrast-enhanced ultrasound (CEUS). PATIENTS AND METHODS: From April 2020 until July 2020, 11 consecutive patients with RT-PCR-confirmed COVID-19 and PPLs sized over 5 mm were investigated by B-mode ultrasound (B-US) and CEUS. The homogeneity of enhancement (homogeneous and inhomogeneous) was examined retrospectively using CEUS. An inhomogeneous enhancement was defined as a perfused lesion with coexisting non-perfused areas (NPA). RESULTS: On B-US, all 11 patients showed an interstitial syndrome (B-lines) with PPLs between 0.5 and 6 cm. On CEUS, all cases showed peripheral NPA during the complete CEUS examination. One patient underwent a partial lung resection with subsequent histopathological examination. The histological examination showed vasculitis, microthrombus in the alveolar capillary, and small obliterated vessels. CONCLUSION: In our case series, PPLs in patients with RT-PCR-confirmed COVID-19 infection presented a CEUS pattern with NPA during the complete CEUS examination. Our findings suggest a peripheral pulmonary perfusion disturbance in patients with COVID-19 infection. In 1 case, the histopathological correlation with the perfusion disturbance in the PPL was proven.

[Spleen biopsy: "pros and cons" or better "when and when not?"] / "Pro und contra Milzpunktion" oder besser "wann und wann nicht?".

Due to the relatively high complication rate, the necessity of a spleen biopsy is controversially discussed. In establishing its indication, the clinical background and performed diagnostics must be considered. Based on the medical history, imaging procedures and sonographic course, different clinical scenarios are conceivable. The aim of this review is to describe the indications of splenic biopsy considering various clinical scenarios.

[Potential of ultrasound in allogeneic stem cell transplantation and transplant-related complications]. / Potenzial des Ultraschalls bei allogener Stammzelltransplantation und transplantationsassoziierten Komplikationen.

Allogeneic hematopoietic stem cell transplantation (HCT) is a complex therapeutic procedure causing significant morbidity and mortality, including the gastrointestinal tract. Early diagnosis and treatment of HCT-associated complications are, therefore, of utmost importance to improve overall HCT outcome. Sonography can be a powerful diagnostic tool and is easily accessible at the bedside of HCT patients. In the hands of a sonography-experienced physician, it allows for instant diagnosis and can also rule out several important transplant-associated complications. Here we review available evidence on the diagnostic and clinical value of ultrasound prior, during and after HCT.