Click here to


Are you sure ?

Yes, do it No, cancel

Dose Reduction and Standardization in Enteric Tube Placement Portable Radiography

EL Marshall*, W Klejch , T Kinsey , J Spano-Rzepecki , V Mamyan , AH Dachman , I Reiser , ZF Lu , The University of Chicago, Chicago, IL


(Thursday, 7/18/2019) 1:00 PM - 3:00 PM

Room: 302

Purpose: Abdominal radiography is the gold-standard for confirming enteric tube placement and location. This study is to develop a new low-exposure protocol for this commonly performed portable radiographic exam. Techniques, energy (kVp) and tube current time product (mAs), were defined as a function of patient body habitus and presence of a ventilator.

Methods: To quantify current state-of-practice, a sample population of tube placement images was collected. Technologists, blinded to the goal, recorded distances from the x-ray tube to patient, x-ray tube to detector, body mass index, and patient ventilation status. This information, in conjunction with phantom imaging of various enteric tubes, was used to establish size-specific imaging protocols. Nasogastric and Dobhoff tubes were positioned between a torso phantom and sheets of tissue-equivalent material and imaged on a Shimadzu portable (MUX-200D-XC) under multiple kVp and mAs combinations. Images were analyzed for exposure index (EI) and tube conspicuity. Tube appearances in phantom images were assigned a numeric conspicuity score by a radiologist: not visualized (0) to diagnostic (3).

Results: Phantom images with EI from 7 to 631 over thicknesses of 9 to 15 inches were scored for tube conspicuity. All images scored at least a 3, indicating all were diagnostic for the task of confirming tube placement, even at the lowest EI. Based on these results, an EI goal of 20-30 was set for four patient size bins. Low-dose protocols were then developed by down scaling patient baseline data to the new EI goal.

Conclusion: Following review and refinement of enteric tube placement portable radiograph techniques, it has been demonstrated that a task-optimized protocol provides two key benefits. One is a substantial reduction in dose (-90%) and two creation of a standardized level of image quality performance to confirm enteric tube placement.


Not Applicable / None Entered.


Not Applicable / None Entered.

Contact Email