Comparison of endoscopic ultrasound, computed tomography and magnetic resonance imaging in assessment of detailed structures of pancreatic cystic neoplasms

AIM To evaluate the advantages of endoscopic ultrasound(EUS) in the assessment of detailed structures of pancreatic cystic neoplasms(PCNs) compared to computed tomography(CT) and magnetic resonance imaging(MRI).METHODS All patients with indeterminate PCNs underwent CT, MRI, and EUS. The detailed information, including size, number, the presence of a papilla/nodule, the presence of a septum, and the morphology of the pancreatic duct of PCNs were compared among the three imaging modalities. The size of each PCN was determined using the largest diameter measured. A cyst consisting of several small cysts was referred to as a motherdaughter cyst. Disagreement among the three imaging modalities regarding the total number of mother cysts resulted in the assumption that the correct number was the one in which the majority of imaging modalities indicated.RESULTS A total of 52 females and 16 males were evaluated. The median size of the cysts was 42.5 mm by EUS, 42.0 mm by CT and 38.0 mm by MRI; there was no significant difference in size as assessed among the three imaging techniques. The diagnostic sensitivity and ability of EUS to classify PCNs were 98.5%(67/68) and 92.6%(63/68), respectively. These percentages were higher than those of CT(73.1%, P < 0.001; 17.1%, P < 0.001) and MRI(81.3%, P = 0.001; 20.3%, P < 0.001). EUS was also able to better assess the number of daughter cysts in mother cysts than CT(P = 0.003); however, there was no significant difference between EUS and MRI in assessing mother-daughter cysts(P = 0.254). The papilla/nodule detection rate by EUS was 35.3%(24/68), much higher than those by CT(5.8%, 3/52) and MRI(6.3%, 4/64). The detection rate of the septum by EUS was 60.3%(41/68), which was higher than those by CT(34.6%, 18/52) and by MRI(46.9%, 30/64); the difference between EUS and CT was significant(P = 0.02). The rate of visualizing the pancreatic duct using EUS was 100%, whereas using CT and MRI it was less than 10%.CONCLUSION EUS helps visualize the detailed structures of PCNs and has many advantages over CT and MRI. EUS is valuable in the diagnosis and assessment of PCNs.

Research Progress of Geophysical Exploration in Karatungk Mine in Northern Xinjiang,China

Karatungk Mine in northern Xinjiang,China,which is a large-scale magmatic Cu-Ni sulfide mine in the Central Asian orogenic belt,has a long history of mining.The mine is located at the merging belt between Altay orogenic belt and Junggar Basin,and has strong tectonic activities.In recent years,mining source detection has become an important target for mineral exploration due to the difficulties in ore body exploitation.In this paper,we systematically summarize the achievements of the geophysical explorations in Karatungk Mine from various aspects,including tectonic backgrounds of the mine,dynamic mechanisms,geophysical characteristics and scientific challenges in the future.Because of the restrictions of observation density and analysis methods,the fine geometrical structure of the mine cannot be completely characterized yet.Therefore,in order to obtain the high-resolution structure and detailed spatial distribution of orebodies,researchers should focus on combining multiple geophysical methods,developing high-resolution imaging methods,and improving petro physical experiments in the future.