CEUS

Repozytorium

Poniższe artykuły zawierają specjalistyczne treści naukowe przeznaczone dla personelu medycznego zajmujacego się ultrasonografią. Treści te dotyczą zaawansowanej diagnostyki różnicowej i nie powinny być interpretowane przez pacjentów jako zalecenia medyczne lub rozpoznanie

The following articles contain specialized scientific content intended for medical personnel practicing ultrasonography. This content concerns advanced differential diagnosis and should not be interpreted by patients as medical advice or a diagnosis.

Contrast-Enhanced Ultrasound (CEUS)

Contrast-enhanced ultrasound (CEUS) is a microvascular imaging technique that uses intravenously administered contrast agents composed of gas microbubbles stabilized by a shell. The microbubbles remain within the vascular compartment and respond strongly to the ultrasound wave, enabling continuous, real-time perfusion imaging when a low mechanical index is used. Unlike computed tomography, CEUS does not use ionizing radiation, and its contrast agents are not nephrotoxic and do not require serum creatinine assessment before the examination [1–3].

CEUS interpretation is based on assessing the relative enhancement of a lesion compared with the surrounding parenchyma, its homogeneity, and its dynamics during consecutive phases of the examination. In the liver, the arterial, portal venous, and late phases are distinguished. In other organs, which do not have a dual blood supply, assessment primarily includes the early and late phases. Key concepts include hyperenhancement, isoenhancement, and hypoenhancement, as well as contrast washout, whose onset and degree are diagnostically important. CEUS depicts perfusion within the examined area with very high temporal resolution and may therefore reveal transient vascular patterns that are not visible on Doppler imaging or are missed by the limited number of phases acquired with CT or MRI [1, 2].

Focal liver lesions

The most firmly established indication for CEUS is the characterization of focal liver lesions detected on B-mode ultrasound, CT, or MRI. In a healthy liver, peripheral nodular enhancement with centripetal fill-in is suggestive of a hemangioma, whereas rapid homogeneous arterial-phase enhancement with a spoke-wheel vascular pattern and persistent isoenhancement in later phases may correspond to focal nodular hyperplasia (FNH). Malignant lesions most commonly demonstrate washout during the portal venous or late phase, although its onset and intensity depend on the tumor’s biology [1, 2].

In patients at high risk of hepatocellular carcinoma (HCC), interpretation can be standardized using CEUS LI-RADS. Typical HCC is characterized by non-rim arterial-phase hyperenhancement followed by late and mild washout. Early or marked washout increases the probability of a non-HCC malignancy and leads to an LR-M classification. CEUS LI-RADS should be applied only in an appropriately defined high-risk population and not to every incidentally detected focal lesion [1, 4, 5].

CEUS also plays an important role in monitoring ablative treatment. The absence of enhancement within the ablation zone supports successful necrosis, whereas focal peripheral or nodular enhancement may indicate residual viable tumor tissue. The examination can be performed immediately after the procedure and repeated without radiation exposure; however, the findings should be interpreted in light of the time elapsed since the intervention and reactive changes in the surrounding parenchyma [1, 2].

Kidneys and cystic lesions

In the kidneys, CEUS can detect even minimal blood flow within the septa, walls, and mural nodules of cystic lesions. It therefore helps distinguish avascular material, such as a clot or proteinaceous content, from genuine solid tissue. CEUS is useful for evaluating lesions that are indeterminate on conventional ultrasound, differentiating tumors from pseudotumors, diagnosing infarction or cortical necrosis, and monitoring infectious complications and the effects of ablation [3, 6].

CEUS-specific adaptations of the Bosniak classification are used to describe cystic renal lesions. Because of its high sensitivity to microvascular perfusion, CEUS may depict more thin septa and subtle enhancement than CT, sometimes resulting in assignment to a higher category. Findings should therefore be interpreted within the classification designed for the imaging method used rather than by directly transferring CT criteria [3, 6].

Pancreas

CEUS complements transabdominal ultrasound in the assessment of pancreatic lesions visible on B-mode imaging. Pancreatic ductal adenocarcinoma is usually less vascular than the surrounding parenchyma and remains hypoenhancing during the early phase. Neuroendocrine tumors more often demonstrate intense hyperenhancement, whereas focal pancreatitis may show enhancement more similar to that of normal pancreatic parenchyma. These patterns are not entirely specific, but they may help guide further diagnostic evaluation [3, 7].

The technique also makes it possible to distinguish vascularized solid components from fluid-filled or necrotic areas, define lesion margins, and select the most representative biopsy target. CEUS does not, however, replace multiphasic CT, MRI, endoscopic ultrasound, or tissue sampling in lesions suspicious for malignancy. Its greatest value lies in its use as part of a multiparametric diagnostic approach and as a problem-solving tool for selected indeterminate findings [3, 7].

Spleen, bowel, and superficial organs

In the spleen, CEUS may support the differential diagnosis of focal lesions, detection of infarctions, and assessment of trauma. Persistent late-phase enhancement is more common in benign lesions, whereas progressive washout raises suspicion of malignancy, although it is not a stand-alone diagnostic criterion [3].

In the gastrointestinal tract, CEUS enables assessment of perfusion in a thickened bowel wall, inflammatory activity, abscesses, fistulas, and ischemic complications. It is particularly useful in inflammatory bowel disease, where it can complement intestinal ultrasonography in evaluating inflammatory activity and treatment response. Findings should always be interpreted together with B-mode imaging, Doppler findings, clinical symptoms, and laboratory results [3].

In the thyroid, breast, lymph nodes, and salivary glands, CEUS may reveal heterogeneous perfusion, irregular non-enhancing areas, and rapid washout associated with malignancy. However, the overlap between enhancement patterns in benign, inflammatory, and neoplastic lesions limits the independent diagnostic value of this technique. CEUS does not replace the relevant risk-classification systems or biopsy, but it may support selection of the sampling site, particularly by helping avoid areas of necrosis [3].

Interventional applications

CEUS may improve the effectiveness of ultrasound-guided procedures. It helps visualize lesions that are poorly seen on B-mode imaging, identifies viable and vascularized portions of a tumor for biopsy, and distinguishes them from necrosis. It also enables intraprocedural assessment of liver, kidney, and other organ lesion ablation, as well as early detection of residual perfusion requiring retreatment [1, 3].

Safety and limitations

Contrast agents used in CEUS have a favorable safety profile, and severe hypersensitivity reactions are very rare. Microbubbles are eliminated primarily through the lungs, while the shell components are metabolized independently of glomerular filtration. CEUS is therefore particularly valuable in patients with renal impairment or contraindications to iodinated and gadolinium-based contrast agents. Nevertheless, it remains necessary to obtain an appropriate medical history, understand the characteristics of the specific agent used, and be prepared to treat an anaphylactic reaction [1–3].

Some limitations of CEUS are shared with conventional ultrasonography, including operator dependence, obesity, bowel gas, deep lesion location, a limited acoustic window, and difficulty assessing the entire organ simultaneously. The examination also requires appropriate selection of the mechanical index, imaging field, contrast dose, and recording time. Incorrect technique may lead to microbubble destruction, masking of enhancement, or erroneous assessment of washout [1–3].

CEUS should be regarded as a targeted problem-solving examination that combines B-mode morphology with real-time perfusion imaging. Its greatest advantage is the ability to rapidly characterize the vascularity of a detected lesion without radiation or a nephrotoxic contrast agent. Its highest clinical value is achieved when the result is incorporated into a multiparametric diagnostic algorithm that considers the clinical context, organ-specific guidelines, and indications for CT, MRI, EUS, or biopsy [1–3].

CEUS references

  1. Dietrich CF, Nolsøe CP, Barr RG, et al. Guidelines and good clinical practice recommendations for contrast-enhanced ultrasound (CEUS) in the liver—update 2020. Ultraschall Med. 2020;41(5):562–585. doi:10.1055/a-1177-0530.
  2. Dietrich CF, Nolsøe CP, Barr RG, et al. Guidelines and good clinical practice recommendations for contrast-enhanced ultrasound (CEUS) in the liver—update 2020. Ultrasound Med Biol. 2020;46(12):2579–2604. doi:10.1016/j.ultrasmedbio.2020.04.030.
  3. Sidhu PS, Cantisani V, Dietrich CF, et al. The EFSUMB guidelines and recommendations for the clinical practice of contrast-enhanced ultrasound (CEUS) in non-hepatic applications: update 2017 (long version). Ultraschall Med. 2018;39:e2–e44. doi:10.1055/a-0586-1107.
  4. Wilson SR, Lyshchik A, Piscaglia F, et al. CEUS LI-RADS: algorithm, implementation, and key differences from CT/MRI. Abdom Radiol (NY). 2018;43:127–142. doi:10.1007/s00261-017-1250-0.
  5. Kim TK, Noh SY, Wilson SR, et al. Contrast-enhanced ultrasound liver imaging reporting and data system 2017: a review of important differences compared to the CT/MRI system. Clin Mol Hepatol. 2017;23(4):280–289. doi:10.3350/cmh.2017.0037.
  6. Masino F, Eusebi L, Bertolotto M, et al. Contrast-enhanced ultrasound in renal cystic lesions: an update. J Med Ultrason. 2024;51:635–647. doi:10.1007/s10396-024-01489-x.
  7. D’Onofrio M, De Robertis R, Barbi E, Martone E, Girelli R, Paiella S. Focal pancreatic lesions: role of contrast-enhanced ultrasonography. J Ultrasound. 2021;24:427–436.
  8. Yusuf GT, Sellars ME, Deganello A, et al. Retrospective analysis of the safety and cost implications of pediatric contrast-enhanced ultrasound at a single center. AJR Am J Roentgenol. 2017;208:446–452.

Poniższe artykuły zawierają specjalistyczne treści naukowe przeznaczone dla personelu medycznego zajmujacego się ultrasonografią. Treści te dotyczą zaawansowanej diagnostyki różnicowej i nie powinny być interpretowane przez pacjentów jako zalecenia medyczne lub rozpoznanie

The following articles contain specialized scientific content intended for medical personnel practicing ultrasonography. This content concerns advanced differential diagnosis and should not be interpreted by patients as medical advice or a diagnosis.

Art 1. CEUS with SF₆ Microbubbles — Patient Qualification, Safety and Clinical Applications. Contrast-enhanced ultrasound (CEUS) using intravenous microbubbles containing sulfur hexafluoride (SF₆) is a dynamic method for assessing tissue perfusion and vascularity in real time. In Europe, the most commonly used agent is SonoVue; in the United States, the corresponding product name is Lumason. The current Summary of Product Characteristics (SmPC) and the formulation available in the relevant market should always be verified. Korczyk R01.09.2026

Art 2. Contrast-Enhanced Ultrasound in the Evaluation of Complex Renal Cystic Lesions: A Scoping Review of CEUS-Adapted Bosniak Classification, Qualitative Imaging Features and Quantitative Time–Intensity Curve Analysis. Complex renal cystic lesions represent an important diagnostic challenge, as they encompass a broad spectrum of entities, ranging from benign lesions requiring no treatment to cystic-solid renal masses with malignant potential. On B-mode ultrasound, differentiating a simple cyst from a lesion with more complex architecture may be difficult, particularly when subtle septa, wall thickening, mural nodules or solid components are present. Identification of such features usually requires further contrast-enhanced imaging, most commonly contrast-enhanced computed tomography (CECT) or magnetic resonance imaging (MRI). Korczyk R 12.09.2026

Art3. Diagnostic value of CEUS in detecting small (≤2 cm) HCC lesions in patients with liver cirrhosis: a scoping review considering obesity (BMI ≥30 kg/m²) and grade II–III ascites. Small focal lesions (≤20 mm) in cirrhotic livers represent a major diagnostic challenge. Although contrast-enhanced ultrasound (CEUS) enables real-time perfusion assessment, its performance varies depending on the diagnostic algorithms and reference standards applied. This scoping review aimed to map the literature on the diagnostic performance of CEUS for nodules ≤20 mm, assess the role of CEUS LI-RADS, and identify evidence gaps in populations with a suboptimal acoustic window, including patients with high BMI or ascites. Korczyk R 12.09.2026