Abstract
Background/Objectives: Colonoscopies have some limitations that result in a miss rate detection of polyps. Microwave imaging has been demonstrated to detect colorectal polyps based on their dielectric properties in synthetic phantoms, ex vivo tissues and in vivo animal models. This study aims to evaluate, for the first time, the feasibility, safety and performance of microwave-based colonoscopy for diagnosis of polyps in real-time explorations in humans. Methods: This was a single-center, prospective, observational study. Patients referred for diagnostic colonoscopy were explored with a device with microwave antennas which was attached to the tip of a standard colonoscope. The primary outcomes were rate of cecal intubation, adverse events, mural injuries and performance metrics for the detection of polyps. Secondary outcomes were the following: patients' subjective feedback, procedural time and perception of difficulty according to the endoscopist. Results: Fifteen patients were enrolled. Cecal intubation rate was 100%, with a mean time of 12.7 ± 4.9 min (range 4-22). Use of the device did not affect the endoscopic image, and polypectomy was successfully performed in all cases. In on scale from zero (not difficult) to four (very difficult), the maneuverability during the insertion was considered ≤2 in the 86.7% (13/15) of colonoscopies. Only 16 incidents were reported in 14 patients: 11 (67%) superficial hematomas, 2 minor rectal bleedings, 1 anal fissure, 1 rhinorrhea and 1 headache. Most of the patients (94%) reported no discomfort or minimal discomfort before discharge (Gloucester score 1 and 2, respectively). In the six patients with 23 polyps used for the performance analysis, the sensitivity and specificity were 86.9% and 72.0%, respectively. Conclusions: microwave-based colonoscopy is safe and feasible and has the potential to detect polyps in real colonoscopies.