膵疾患診療における EUS-elastography の現状と展望

Elastography used in endoscopic ultrasound (EUS)-elastography for pancreatic disease is roughly classified into strain elastography (SE) and shear wave elastography (SWE). Most of the previous studies have been performed using SE. Methods of interpreting the results of SE include recognizing the pattern of the image in the region of interest (ROI), using the SR (strain ratio) to compare the hardness of adipose tissue or connective tissue and the hardness of the lesion, and histogram analysis of the hardness distribution in the target lesion. The first two methods have poor reproducibility, require multiple evaluations, and require careful attention to interpretation of the results. These two methods have been used mainly for focal pancreatic diseases. Histogram analysis has excellent reproducibility and has been used for evaluation of chronic pancreatitis and for evaluating hardness distribution in similar lesions. Since the hardness of the pancreas increases with aging, it is necessary to consider the patient's age in the diagnosis of pancreatic disorders using EUS-elastography.