Harmonic ultrasonography for the detection of microlithiasis in the gallbladder

Practical approach to linear endoscopic ultrasound examination of the gallbladder

The gallbladder (GB) is a susceptible organ, prone to various pathologies that can be identified using different imaging techniques. Transabdominal ultrasound (TUS) is typically the initial diagnostic method due to its numerous well-established advantages. However, in cases of uncertainty or when a definitive diagnosis cannot be established, computed tomography (CT) or magnetic resonance imaging may be employed to provide more detailed information. Nevertheless, CT scans may sometimes offer inadequate spatial resolution, which can limit the differentiation of GB lesions, particularly when smaller yet clinically relevant abnormalities are involved. Conversely, endoscopic ultrasound (EUS) provides higher frequency compared to TUS, superior spatial resolution, and the option for contrast-enhanced harmonic imaging, enabling a more comprehensive examination. Thus, EUS can serve as a supplementary tool when conventional imaging methods are insufficient. This review will describe the standard EUS examination of the GB, focusing on its endosonographic characteristics in various GB pathologies.

Endoscopic Ultrasound in Pediatric Patients With Pancreatobiliary Disease

BACKGROUND

Endoscopic ultrasound (EUS) is one of the greatest advances of the last few decades for the diagnostic and therapeutic approach of gastrointestinal diseases in adults. However, there are limitations to the application of the procedure in the pediatric population. The aim of this study was to describe the diagnostic yield and therapeutic role of EUS in pediatric patients with pancreatobiliary disease.

MATERIALS AND METHODS

A retrospective study was performed on a prospective database of pediatric patients who underwent diagnostic and therapeutic endosonographic procedures. All patients seen in a 12-year period were included.

RESULTS

A total of 54 patients were included, including 32 (59.3%) female individuals, with an average age of 16 (9 to 17) years. EUS was abnormal in 46 (85%) patients. Of the abnormal procedures, 4 (7.4%) corresponded to therapeutic ones. The main indication of the study was recurrent acute pancreatitis in 29 (54%). The main endosonographic findings were microlithiasis in 14 (25.9%), chronic pancreatitis in 9 (16.7%), and pancreatic tumors in 6 (11.1%) patients. Follow-up was performed in 31 (57.4%) patients, 19/31 patients underwent surgery, and 4/31 patients had endoscopic retrograde cholangiopancreatography. The median follow-up was 910 (2 to 3916) days. In 100% of the patients with follow-up, the initial diagnosis of EUS was confirmed.

CONCLUSION

EUS is a useful and safe tool in the pediatric population with pancreatobiliary diseases.

Similarities and differences between biliary sludge and microlithiasis: Their clinical and pathophysiological significances

The terms biliary sludge and cholesterol microlithiasis (hereafter referred to as microlithiasis) were originated from different diagnostic techniques and may represent different stages of cholesterol gallstone disease. Although the pathogenesis of biliary sludge and microlithiasis may be similar, microlithiasis could be preceded by biliary sludge, followed by persistent precipitation and aggregation of solid cholesterol crystals, and eventually, gallstone formation. Many clinical conditions are clearly associated with the formation of biliary sludge and microlithiasis, including total parenteral nutrition, rapid weight loss, pregnancy, organ transplantation, administration of certain medications, and a variety of acute and chronic illnesses. Numerous studies have demonstrated complete resolution of biliary sludge in approximately 40% of patients, a cyclic pattern of disappearing and reappearing in about 40%, and progression to gallstones in nearly 20%. Although only a minority of patients with ultrasonographic demonstration of biliary sludge develop gallstones, it is still a matter of controversy whether microlithiasis could eventually evolve to cholesterol gallstones. Biliary sludge and microlithiasis are asymptomatic in the vast majority of patients; however, they can cause biliary colic, acute cholecystitis, and acute pancreatitis. Biliary sludge and microlithiasis are most often diagnosed ultrasonographically and bile microscopy is considered the gold standard for their diagnosis. Specific measures to prevent the development of biliary sludge are not practical or cost-effective in the general population. Laparoscopic cholecystectomy offers the most definitive therapy on biliary sludge. Endoscopic sphincterotomy or surgical intervention is effective for microlithiasis-induced pancreatitis. Ursodeoxycholic acid can effectively prevent the recurrence of solid cholesterol crystals and significantly reduce the risk of recurrent pancreatitis.

Tumefactive Gallbladder Sludge at US: Prevalence and Clinical Importance

Purpose To evaluate the prevalence of tumefactive sludge of the gallbladder detected at ultrasonography (US) and to assess whether any clinical and imaging differences exist between benign and malignant tumefactive sludge. Materials and Methods The institutional review board approved this retrospective study. The requirement for informed consent was waived. The study included a cohort (n = 6898) of patients with gallbladder sludge drawn from all adults (n = 115 178) who underwent abdominal US between March 2001 and March 2015. Tumefactive sludge was identified according to the following US findings: (a) nonmovable mass-like lesion and (b) absence of posterior acoustic shadowing at B-mode US and vascularity at color Doppler US. Follow-up examinations were arranged to ascertain whether the results showed true sludge or gallbladder cancer. Risk factors for malignant tumefactive sludge based on clinical and US characteristics were identified with multivariate logistic regression analysis. Results The prevalence of gallbladder and tumefactive sludge at abdominal US during the observation period was 6.0% (6898 of 115 178) and 0.1% (135 of 115 178), respectively. Twenty-eight (20.7%) patients were lost to follow-up. Of the 107 with tumefactive sludge, 15 (14%) were confirmed to have malignant tumefactive sludge. The risk factors for malignant tumefactive sludge were old age (odds ratio [OR], 1.06; P = .035), female sex (OR, 5.48; P = .014), and absence of hyperechoic spots within the sludge (OR, 6.78; P = .008). Conclusion Although the prevalence of tumefactive sludge at US was rare, a considerable proportion of patients had a malignancy. Careful follow-up is essential, especially for older patients, women, and those with an absence of hyperechoic spots at US. ^© RSNA, 2016 Online supplemental material is available for this article.