A new radial mechanical puncture echoendoscope: prospective comparison with standard linear and radial echoendoscopes in assessment of focal pancreatic lesions

Background: A new mechanical puncture-echoendoscope was evaluated by comparing it with conventional linear and radial echoendoscopes. The new instrument has a 300degrees image field parallel to the axis of the echoendoscope, which could potentially improve accuracy and facilitate assessment of suspected pancreatic lesions before needle puncture. Methods: Twenty consecutive patients with suspected pancreatic lesions were evaluated endosonographically, including fine needle aspiration (FNA). The initial assessment was performed by random selection of either the new instrument or the standard linear echoendoscope. After completing the assessment including FNA, the procedure with FNA was repeated with the other puncture echoendoscope. The findings with these 2 instruments were compared to those with the conventional radial scanning echoendoscope. Results: FNA was performed in 17 patients with pancreatic head lesions. In 3 patients without a visible pancreatic mass lymph, nodes greater than 10 mm in diameter were aspirated. The ability to image the needle, number of punctures, and material obtained were comparable for both puncture echoendoscopes. There were no significant differences with regard to time required for FNA with both puncture echoendoscopes or in the assessment of surrounding structures with all 3 instruments. The results of cytopathologic evaluation of material obtained by FNA were similar in 15 cases. The new instrument could not be passed into the esophagus in 1 patient because of an esophageal stricture. Conclusions: The performance of the new mechanical puncture echoendoscope was satisfactory for assessment and FNA of pancreatic lesions. The additional use of the conventional radial scanning echoendoscope provided no advantage with regard to any parameter assessed.