Background

Retroflexion is essential in diagnostic endoscopy. We examined articulation abilities of reusable diagnostic gastroscopes (RUDG) and single-use diagnostic gastroscopes (SUDG) with respect to the degree of retroflexion achieved.

Methods

RUDGs undergo degradation of their maximum backwards articulation during their lifetime, including after anticipated repairs. In December 2023, we compared the retroflexion between 2 RUDGs (Olympus GIF-HQ190) and 2 SUDGs (Ambu aScope Gastro). The RUDGs were randomly selected from available endoscopes inventoried at our GI center. Endoscopes selected included one with and one without repairs. Gastroscopes were clamped to a board and flexed backwards until the maximum sustained angle was measured with a protractor both with and without instruments in the working channel.

Results

RUDGs achieved an average backwards flexion of 164 degrees while SUDGs achieved an average of 210 degrees backwards flexion. Introduction of an injection needle decreased backwards flexion from 164 to 132 degrees in the RUDGs and SUDGs decreased from 210 to 205 degrees. Introduction of a biopsy forcep decreased backward flexion to 138 degrees in the RUDG's versus 201 degrees in the SUDG's.

Conclusions

SUDGs achieved 21.9% superior retroflexion at baseline and over 30% superior retroflexion with instruments compared to the RUDGs. We observed decreased retroflexion in RUDGs compared to manufacturer listed specifications of 210 degrees, which is likely due to deterioration sustained during routine use and reprocessing. We observed SUDGs to perform consistently like-new. Decreased articulation may limit the abilities of RUDGs compared to SUDGs.