How Can We Manage Gallbladder Lesions by Transabdominal Ultrasound?

Abstract

The most important role of ultrasound (US) in the management of gallbladder (GB) lesions is to detect lesions earlier and differentiate them from GB carcinoma (GBC). To avoid overlooking lesions, postural changes and high-frequency transducers with magnified images should be employed. GB lesions are divided into polypoid lesions (GPLs) and wall thickening (GWT). For GPLs, classification into pedunculated and sessile types should be done first. This classification is useful not only for the differential diagnosis but also for the depth diagnosis, as pedunculated carcinomas are confined to the mucosa. Both rapid GB wall blood flow (GWBF) and the irregularity of color signal patterns on Doppler imaging, and heterogeneous enhancement in the venous phase on contrast-enhanced ultrasound (CEUS) suggest GBC. Since GWT occurs in various conditions, subdividing into diffuse and focal forms is important. Unlike diffuse GWT, focal GWT is specific for GB and has a higher incidence of GBC. The discontinuity and irregularity of the innermost hyperechoic layer and irregular or disrupted GB wall layer structure suggest GBC. Rapid GWBF is also useful for the diagnosis of wall-thickened type GBC and pancreaticobiliary maljunction. Detailed B-mode evaluation using high-frequency transducers, combined with Doppler imaging and CEUS, enables a more accurate diagnosis.

Development and Validation of a Preoperative Nomogram for Predicting Benign and Malignant Gallbladder Polypoid Lesions

“…Gallbladder lesions are broadly divided into wall thickening (GWT) and polypoid lesions (GPs) according to the morphology performance in imaging modalities that GWTs should be determined as wall thickening of 4 mm or more, while GPs are defined as focal elevation or protrusions that are distinguishable from the surrounding mucosa including early gallbladder cancer and neoplastic and non-neoplastic polyps (11,12). For instance, the most common type of non-neoplastic polyp is cholesterol polyp, which accounts for about 60% of gallbladder polyps and tends to remain benign.…”

“…In addition, traditional radiographic diagnosis by visual observation is usually limited by human visual perception, while radiomics was a useful tool, which enables quantification of diseases by extracting information that cannot be directly recognized by the human brain from images and ultimately assists the surgeon especially in diagnosis and efficacy prediction (6,8,11). For the achievement of the radiomics signature from image, ultrasonography (US) is one of the most effective screening methods used for assessment of GPs.…”

Imaging patterns of wall thickening type of gallbladder cancer

“…The diffuse pattern of GBC can be symmetrical or asymmetrical. The presence of asymmetrical thickening with loss of integrity of the mucosa and loss of the layered appearance that can be easily identified on high resolution ultrasound (HRUS) helps us identify early GBCs and differentiate them from innocuous thickening [11][12][13]. This is depicted in Figure 1.…”

The Role of Endoscopic Ultrasound in the Diagnosis of Gallbladder Lesions

“…GB lesions are broadly divided into protuberant lesions and wall-thickening lesions [18,19]. Protuberant lesions are defined as a focal elevation or a protrusion that can be distinguished from the surrounding mucosa [15,20].…”