Prospective, randomized, comparative study of delineation capability of radial scanning and curved linear array endoscopic ultrasound for the pancreaticobiliary region

Background and study aims: There are two types of endoscopic ultrasound (EUS) endoscope, the radial scanning (RS) and the curved linear array (CL). The type of EUS endoscope used at a first intent depends on local expertise, local habits and sometimes on how the examination is reimbursed. In Japan, RS is mainly used for observation, whereas CL is primarily used for histopathological diagnosis and treatment. We compared the imaging capabilities of RS and CL in evaluating the pancreaticobiliary region, a study which has not been performed previously.

Patients and methods: This prospective and randomized trial included 200 patients undergoing endoscopic ultrasonography of the pancreaticobiliary region by RS (n = 99) or CL (n = 101). The primary end point was the basal imaging capability of each technique. Eleven pancreaticobiliary areas were assessed and scored (range, 0 – 2). Endoscopists evaluated each criterion, and a transcriber recorded the decisions in real time.

Results: The mean imaging scores in the RS and CL groups were 18.39 and 19.62, respectively (significantly higher in CL, 95 %CI: 0.82 – 1.64). Although no significant difference in imaging capability for the pancreatic head, body, or tail was observed between CL and RS, the imaging capability of CL for the pancreatic head – body transition region was superior to that of RS. Although no significant difference in imaging capability for the middle and inferior bile duct or the cystic duct was observed between CL and RS, the imaging capability of RS for the major duodenal papilla and gallbladder was superior to that of CL. For the area from the hepatic portal region to the superior bile duct, the imaging capability of CL was superior. In the delineation of the branch area of the celiac and superior mesenteric arteries, CL was also superior to RS.

Conclusions: The non-inferiority of the overall imaging capability of CL to that of RS was demonstrated. CL was superior in the delineation of the pancreatic head – body transition region, the area from the hepatic portal region to the superior bile duct, and the vascular bifurcation, whereas RS was superior in the delineation of the major duodenal papilla and gallbladder. Thus, for detailed evaluations of specific areas, the choice of scope should probably be considered.

• References

• 1 Maguchi H. The roles of endoscopic ultrasonography in the diagnosis of pancreatic tumors. J Hepatobiliary Pancreat Surg 2004; 11: 1-3
• 2 Canto MI, Goggins M, Yeo CJ et al. Screening for pancreatic neoplasia in high-risk individuals: an EUS-based approach. Clin Gastroenterol Hepatol 2004; 2: 606-621
• 3 Liu CL, Lo CM, Chan JK et al. EUS for detection of occult cholelithiasis in patients with idiopathic pancreatitis. Gastrointest Endosc 2000; 51: 28-32
• 4 Canto MI, Chak A, Stellato T et al. Endoscopic ultrasound versus cholangiography for the diagnosis of choledocholithiasis. Gastrointest Endosc 1998; 47: 439-448
• 5 Tierney WM, Adler DG, Chand B et al. Echoendoscopes. Gastrointest Endosc 2007; 66: 435-442
• 6 Tierney WM, Kochman ML, Scheiman JM. Computed tomography versus endoscopic ultrasonography for staging of pancreatic cancer. Ann Intern Med 2005; 142: 590-591
• 7 Varadarajulu S, Wilcox CM, Eloubeidi MA. Impact of EUS in the evaluation of pancreaticobiliary disorders in children. Gastrointest Endosc 2005; 62: 239-244
• 8 Vilmann P, Jacobsen GK, Henriksen FW et al. Endoscopic ultrasonography with guided fine needle aspiration biopsy in pancreas disease. Gastrointest Endosc 1992; 38 : 172-173
• 9 Wiersema MJ, Kochman ML, Cramer HM et al. Endosonography-guided real-time fine-needle aspiration biopsy. Gastrointest Endosc 1994; 40: 700-707
• 10 Chang KJ, Katz KD, Durbin TE et al. Endoscopic ultrasound-guided fine-needle aspiration. Gastrointest Endosc 1994; 40: 694-699
• 11 Chang KJ, Nguyen P, Erickson RA et al. The clinical utility of endoscopic ultrasound-guided fine-needle aspiration in the diagnosis and staging of pancreas carcinoma. Gastrointest Endosc 1997; 45: 387-393
• 12 Wiersema MJ, Vilmann P, Giovannini M et al. Endosonography-guided fine-needle aspiration biopsy: diagnostic accuracy and complication assessment. Gastroenterology 1997; 112: 1087-1095
• 13 Bhutani MS, Hawes RH, Baron PL et al. Endoscopic ultrasound guided fine needle aspiration of malignant pancreatic lesions. Endoscopy 1997; 29: 854-858
• 14 Katanuma A, Maguchi H, Hashigo S et al. Tumor seeding after endoscopic ultrasound-guided fine-needle aspiration of cancer in the body of the pancreas. Endoscopy 2012; 44: E160-E161
• 15 Katanuma A, Maguchi H, Osanai M et al. The difference in the capability of delineation between convex and radial arrayed echoendoscope for pancreas and biliary tract; Case reports from the standpoint of both convex and radial arrayed echoendoscope. Dig Endosc 2011; 23: 2-8
• 16 Fujita N, Inui K, Kida M et al. Standard imaging techniques in the pancreatobiliary region using radial scanning endoscopic ultrasonography. Dig Endosc 2004; 16 : S118-S133
• 17 Yamao K, Irisawa A, Inoue H et al. Standard imaging techniques of endoscopic ultrasound-guided fine-needle aspiration using a curved linear array echoendoscope. Dig Endosc 2007; 19: S180-S205
• 18 Japanese Society of Biliary Surgery. General rules for surgical and pathological studies on cancer of the biliary tract [Japanese]. 5th edn. Tokyo: Kanehara; 2003
• 19 Kochman ML, Elta GH, Bude R et al. Utility of a linear array ultrasound endoscope in the evaluation of suspected pancreatic disease. J Gastrointest Surg 1998; 2: 217-222
• 20 Gress F, Savides T, Cummings O et al. Radial scanning and linear array endosonography for staging pancreatic cancer: a prospective randomized comparison. Gastrointest Endosc 1997; 45: 138-142
• 21 Siemsen M, Svendsen LB, Knigge U et al. A prospective randomized comparison of curved array and radial endoscopy in patients with esophageal cancer. Gastrointest Endosc 2003; 58: 671-676
• 22 Hara K, Bhatia V, Hijioka S et al. A convex EUS is useful to diagnose vascular invasion of cancer, especially hepatic hilar cancer. Dig Endosc 2012; 23: 26-28