Syed Zaidi

Stent-induced pancreatic ductal and parenchymal changes: correlation of endoscopic ultrasound with ERCP

BACKGROUND Polyethylene pancreatic duct stents induce morphologic changes of the pancreatic duct in the majority of patients. This study was undertaken to determine if parenchymal abnormalities are present in patients undergoing short-term pancreatic duct stenting and to correlate these findings with the pancreatogram obtained at stent removal. METHODS Twenty-five patients underwent pancreatic duct stenting and had an endoscopic ultrasound evaluation of the pancreas at stent removal. The pancreatograms were evaluated at stent removal for ductal irregularity, narrowing, and side branch changes. Endoscopic ultrasound was used to assess for differences in the echo characteristics of the pancreatic parenchyma around the stent compared with the rest of the gland. RESULTS Of the 16 patients evaluated by ERCP at stent removal, 9 (56%) had 1 or more new ductographic changes. Endoscopic ultrasound identified parenchymal changes in the stented region in 17 of 25 patients (68%). Four patients who had parenchymal changes in the stented region on endoscopic ultrasound at stent removal had a follow-up study at a mean time of 16 months. Two patients had (new) changes suggestive of focal chronic pancreatitis in the stented region. CONCLUSION Short-term pancreatic duct stenting induced both ductal and parenchymal changes in more than 50% of patients. Chronic pancreatitis may be a consequence of pancreatic duct stenting.

Radial scanning and linear array endosonography for staging pancreatic cancer: a prospective randomized comparison

BACKGROUND Endoscopic ultrasound (EUS) is known to be accurate for staging pancreatic cancer. Little data exist to determine if linear array or radial scanning EUS is superior for staging pancreatic cancer. This prospective comparison was undertaken to assess the accuracy of linear array and radial scanning EUS for staging pancreatic cancer. METHODS Patients with pancreatic cancer referred for EUS staging were randomized to linear array or radial scanning EUS. Staging accuracy for each was determined by comparison to surgical pathology in those patients going to surgery. RESULTS Seventy-nine patients with pancreatic cancer were enrolled and 33 had surgical resection. Of these, 17 patients were randomized to linear array and 16 to radial scanning EUS. The remaining 46 patients did not have surgery because of comorbid illness or clinically unresectable disease. EUS staging accuracy for linear array was 94% (16 of 17) for T and 71% (12 of 17) for N staging, whereas radial scanning was 88% (14 of 16) for T and 75% (12 of 16) for N staging. For predicting vascular invasion, radial scanning was 100% accurate (16 of 16) while linear array was 94% (16 of 17) accurate. There was one false-negative assessment of invasion using linear array EUS. CONCLUSION Overall, both EUS designs appear equivalent for staging pancreatic cancer and assessing vascular invasion. In view of our findings and the capability for ultrasound-directed fine-needle aspiration with linear array EUS, this instrument may be the preferred choice for evaluating pancreatic masses.

Detection of embryologic ventral pancreatic parenchyma with endoscopic ultrasound

BACKGROUND The prevalence of detecting the embryologic ventral pancreas (ventral anlage) with endoscopic ultrasound (EUS) is unknown. PURPOSE To determine the frequency of, and factors associated with, EUS findings consistent with the ventral anlage. METHODS One hundred patients undergoing upper gastrointestinal EUS for any indication were prospectively evaluated for the presence of a focal, hypoechoic area in the pancreatic head using a radial scanning echoendoscope. Multiple clinical and EUS variables were tested against the ability to detect the ventral anlage. RESULTS The overall detection rate of the ventral anlage was 59%. The ventral anlage was detected in 75% of patients undergoing EUS for nonpancreatic indications, compared to 40% of patients undergoing EUS to evaluate suspected pancreatic disease (p< 0.001). EUS detected the ventral anlage in 72% of patients with a normal EUS-appearing pancreatic head, compared to 29% of patients who had abnormal pancreatic head parenchyma (mass or chronic pancreatitis) on EUS (p < 0.001). Multivariate analysis revealed the only variable associated with detecting the ventral anlage was abnormal pancreatic head parenchyma on EUS. CONCLUSION The ventral anlage is frequently detected during pancreatic EUS, with a significantly lower rate of detection in patients with EUS findings of a pancreatic head mass or diffuse chronic pancreatitis.

Current liver biopsy practices for suspected parenchymal liver diseases in the United States: the evolving role of radiologists

OBJECTIVE:The aim of this study was to determine current liver biopsy practices in the United States.METHODS:We mailed a questionnaire to 260 randomly selected members of the American Association for the Study of Liver Diseases. Statistical analysis was conducted using the χ2 test.RESULTS:A total of 128 members (49%) responded, with 106 responses suitable for inclusion. Of the respondents, 25% had a radiologist perform >50% of their patients’ liver biopsies, whereas 38% personally performed all their patients’ biopsies. During training, 87% of respondents were taught to perform liver biopsy using the “blind” technique, 2% with ultrasound (US) guidance, and 11% both. A total of 76% used US guidance during liver biopsy. More private practitioners than those practicing in academic centers used the “blind” technique (35% vs 18%; p = 0.02) and referred >50% of their patients for liver biopsy to Radiology (36% vs 17%; p = 0.01); desire for real-time US guidance was the main reason in 43% of cases. Of the respondents, 75% used US for safety reasons; 77% of those who did not use US believed that it was unnecessary. Overall, 87% of respondents indicated that patient safety was the most important issue during liver biopsy; only 2% thought that personal convenience and cost-effectiveness were most important.CONCLUSIONS:Respondents’ chief concern was patient safety, and most used US for this reason. Private practitioners were less likely than those practicing in academic centers to use US guidance and were more likely to refer patients to Radiology.