Recent advances and novel methods in pancreatic imaging.

Traditional imaging studies for evaluating pancreatic disease including abdominal ultrasound (US) and computerized tomography (CT) are widely utilized due to their availability, non-invasiveness, and familiarity to practitioners. The addition of endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) has contributed significantly to the clinician's the ability to safely sample tissue, stage malignancy, evaluate the pancreatic ductal anatomy, and look for subtle parenchymal changes in the setting of chronic pancreatitis. The role of endoscopic retrograde cholangiopancreatography (ERCP) has diminished with the use of these less invasive modalities. Limitations in these conventional techniques include a lack of sensitivity and specificity in diagnosing early chronic pancreatitis, difficulties in differentiating malignancy from chronic or focal pancreatitis, and accuracy of staging pancreatic malignancy, particularly with regard to vascular involvement. Several recent advances in traditional imaging techniques have been described, which may improve our ability to accurately diagnose and stage pancreatic disease. Advances have been made in the standard modalities for imaging the pancreas such as multidetector CT, micro-bubble contrast enhanced ultrasound, and secretin stimulated MRCP. Other novel methods of pancreatic imaging have recently been described including EUS elastography, optical coherence tomography, diffusion weighted MRI, and MR spectroscopy. This article will review the recent advances in both traditional pancreatic imaging modalities as well as some of the emerging technologies for imaging evaluating diseases of the pancreas. As experience and clinical evidence accumulate, the role of these imaging techniques will continue to evolve.

Clinical impact of conventional endosonography and endoscopic ultrasound-guided fine-needle aspiration in the assessment of patients with Barrett's esophagus and high-grade dysplasia or intramucosal carcinoma who have been referred for endoscopic ablation therapy.

BACKGROUND AND STUDY AIMS: Endoscopic mucosal resection and photodynamic therapy are exciting, minimally invasive curative techniques that represent an alternative to surgery in patients with Barrett's esophagus and high-grade dysplasia or intramucosal adenocarcinoma. However, there is lack of uniformity regarding which staging method should be used prior to therapy, and some investigators even question whether staging is required prior to ablation. We report our experience with a protocol of conventional endoscopic ultrasound staging prior to endoscopic therapy. PATIENTS AND METHODS: A total of 25 consecutive patients with a diagnosis of high-grade dysplasia or intramucosal adenocarcinoma in Barrett's esophagus who had been referred to the University of Chicago for staging in preparation for endoscopic therapy between March 2002 and November 2004 were included in the study. All 25 patients underwent repeat diagnostic endoscopy and conventional endosonography with a radial echo endoscope. Any suspicious lymph nodes that were detected were sampled using endoscopic ultrasound-guided fine-needle aspiration. RESULTS: Baseline pathology in the 25 patients (mean age 70, range 49-85) revealed high-grade dysplasia in 12 patients and intramucosal carcinoma in 13 patients. Five patients were found to have submucosal invasion on conventional endosonography. Seven patients had suspicious adenopathy, six regional (N1) and one metastatic to the celiac axis (M1a). Fine-needle aspiration confirmed malignancy in five of these seven patients. Based on these results, five patients (20%) were deemed to be unsuitable candidates for endoscopic therapy. CONCLUSIONS: By detecting unsuspected malignant lymphadenopathy, conventional endosonography and endoscopic ultrasound with fine-needle aspiration dramatically changed the course of management in 20% of patients referred for endoscopic therapy of Barrett's esophagus with high-grade dysplasia or intramucosal carcinoma. Based on our results, we believe that conventional endosonography and endoscopic ultrasound with fine-needle aspiration when nodal disease is present should be performed routinely in all patients referred for endoscopic therapy in this setting.

The role of endoscopic retrograde cholangiopancreatography and endoscopic ultrasound in diagnosis and treatment of acute pancreatitis.

Endoscopic retrograde cholangiopancreatography (ERCP) is an important tool for diagnosis and therapy in acute and recurrent pancreatitis. While treatment of biliary disorders leading to pancreatitis is common practice, over the past several years many specialized centers have been directing traditional biliary techniques such as sphincterotomy and stenting towards the pancreas. A justifiable fear of pancreatitis and other complications has caused many endoscopists to shy away from pancreatic endotherapy, but refinements in technique, extensive experience, and most notably the routine use of pancreatic stenting to prevent post-ERCP pancreatitis has opened up the field and allowed for endoscopists in specialized centers around the world to perform diagnostic and therapeutic ERCP of the pancreas safely and effectively. In acute gallstone pancreatitis, the benefit of therapeutic ERCP including biliary sphincterotomy has been proven in randomized controlled trials. There are also data to support the role of ERCP directed at the pancreatic sphincters and ducts in treatment of acute relapsing pancreatitis due to pancreas divisum, sphincter of Oddi dysfunction, smoldering pancreatitis, pancreatic ductal disruptions, and perhaps even in evolving pancreatic necrosis. Many causes of apparently idiopathic pancreatitis can be discovered after an extensive evaluation with endoscopic ultrasound (EUS), magnetic resonance cholangiopancreatography (MRCP) and ERCP with sphincter of Oddi manometry. ERCP often allows treatment of the underlying cause. Because of the inherent risks associated with ERCP, particularly when directed toward the pancreas, the role of ERCP in acute and especially recurrent pancreatitis should be primarily therapeutic with attempts to establish diagnosis whenever possible by less risky techniques including EUS and MRCP. With the added techniques, devices, skill-sets, and experience required, pancreatic endotherapy should preferably be performed in high volume tertiary referral settings. ERCP for diagnosis and treatment of severe or acute relapsing pancreatitis is also best performed using a multidisciplinary approach involving endoscopy, hepatobiliary-pancreatic surgery, and interventional radiology.