Quantitative And Qualitative Eus Elastography
Condition: Normal Pancreatic Tissue
Study type: Observational

Summary: 
      Endoscopic ultrasonography is considered the most accurate methods for the diagnosis and
      staging of chronic inflammatory and neoplastic pancreatic diseases. Differential diagnosis of
      solid pancreatic masses, however, remains a challenge and endoscopic ultrasound-guided fine
      needle aspiration is necessary. Recently, Endoscopic ultrasound elastography has been
      introduced as an alternative method to evaluate tissue stiffness of solid pancreatic masses,
      being an index of tissue elasticity, which may be related to histopathology features (hard
      tissue = blue = neoplastic and soft tissue = red-yellow-green = non-neoplastic). However,
      recently publications show different results using elastography. Moreover, a lack of data in
      Endoscopic ultrasound-elastography exist regarding the compression rate of the probe and the
      diameter of the region of interest under analysis in previously studies that by physics could
      affect the tissue elasticity.

      Based on the hypothesis that elastography could be affected by compression rate of the probe
      and the diameter of the region of interest analyzed the present study aimed to evaluate the
      quantitative (strain ratio) and qualitative endoscopic ultrasound-elastography results
      determined by the compression rate of the probe (measured by the curve of compression in the
      second generation of elastography) and the diameter of the region of interest in normal
      pancreatic tissue.
    

Detailed description: 
      prospective study performed in patients undergoing for upper-endoscopic ultrasound from
      October 31-to end of November 2013. Endoscopic ultrasound-elastography was performed using
      linear Pentax-EUS and "Hitachi-Avius". The quantitative-strain ratio and qualitative
      endoscopic ultrasound-elastography was measured in the body of the pancreas taking in
      consideration the curve of the compression rate of the probe high: +0.4, middle: 0, low: -0.4
      in the largest and smaller region of interest diameters. Analysis for qualitative
      elastography was obtained by the predominant color of the pancreatic area studied. Pictures
      where recorded and quantitative strain ratio data were calculated comparing endoscopic
      ultrasound-elastography of pancreatic tissue with soft tissue (normal mucosal layer: red).
      Finally, a comparative analysis was performed between the results with the mean normal value
      for quantitative strain ratio previously published for normal pancreatic tissue, and between
      the different compression rates of the probe.
    

Intervention name(s): endoscopy ultrasound elastography; EUS-elastography
Intervention type(s): Procedure; Device
Intervention description(s): During a endoscopy ultrasound (EUS) procedure, in patients with normal pancreas at EUS, elastography was performed using a software already included in Hitachi-Avius machine, pressing the button and obtaining colors and pressure curve given by the software
Observational model: Case-Only
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        primary care clinic: patients with upper gastrointestinal submucosal tumors for evaluation
        by endoscopic ultrasound
      
Keywords: Endoscopic Ultrasound elastography; Quantitative elastography; Qualitative elastography; Endoscopic Ultrasound; Elastography