The Aer-O-Scope: Proof of the Concept of a Pneumatic, Skill-Independent, Self-Propelling, Self-Navigating Colonoscope in a Pig Model

Background and Study Aims: Considerable training is needed to enable endoscopists to use the currently available commercial colonoscopes and sigmoidoscopes effectively and safely. The aim of this study was to evaluate the safety and efficacy of the propulsion mechanism incorporated into the Aer-O-Scope® (GI View Ltd., Ramat Gan, Israel) - a novel self-propelled, self-navigating colonic endoscope for diagnostic purposes.
Materials and Methods: Twenty young female pigs underwent complete bowel preparation followed by a sedated examination using the new device. Ten pigs underwent two consecutive procedures, with a wash-out period of 7 days between each procedure. The total number of procedures was 30. Two prototypes of the Aer-O-Scope, with different cable lengths and vehicle balloon sizes (n = 20 and n = 10 for prototypes I and II, respectively) were used. Each examination was followed by a standard colonoscopy for safety evaluation. The insertion length of the Aer-O-Scope was determined by fluoroscopy images.

Results: The colon was adequately clean in 25 procedures. Maximum insertion was achieved in 21 procedures (84 %) - 80 % with prototype I (n = 15) and 90 % with prototype II (n = 10). The time to maximum insertion averaged 8.9 ± 4.4 min (10 ± 4.6 and 6.6 ± 2.9 min for prototypes I and II; P < 0.05), and the withdrawal time averaged 3.4 ± 2.1 and 4.2 ± 3.4 min, respectively. The driving pressures for prototypes I and II averaged 46.3 and 34.5 mbar, respectively. The follow-up conventional colonoscopy identified no mucosal tears or perforations. Minor mucosal petechiae were noted in 43 % of the cases. No adverse events were noted up to 7 days after the procedure.

Conclusions: The propulsion mechanism used in this novel self-propelled, self-navigating colonoscope was effective and safe in pigs.

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