A novel retractable laparoscopic device for mapping gastrointestinal slow wave propagation patterns

Rachel Berry, Niranchan Paskaranandavadivel, Peng Du, Mark L. Trew, Gregory O’Grady, John A. Windsor, Leo K. Cheng

Gastric slow waves regulate peristalsis, and gastric dysrhythmias have been implicated in functional motility disorders. To accurately define slow wave patterns, it is currently necessary to collect high-resolution serosal recordings during open surgery. We therefore developed a novel gastric slow wave mapping device for use during laparoscopic procedures. The device consists of a retractable catheter constructed of a flexible nitinol core coated with Pebax. Once deployed through a 5-mm laparoscopic port, the spiral head is revealed with 32 electrodes at 5 mm intervals. Recordings were validated against a reference electrode array in pigs and tested in a human patient. Recordings from the device and a reference array in pigs were identical in frequency (2.6 cycles per minute; p = 0.91), and activation patterns and velocities were consistent (8.9 ± 0.2 vs 8.7 ± 0.1 mm s(-1); p = 0.2). Device and reference amplitudes were comparable (1.3 ± 0.1 vs 1.4 ± 0.1 mV; p = 0.4), though the device signal-to-noise ratio was higher (17.5 ± 0.6 vs 12.8 ± 0.6 dB; P < 0.0001). In the human patient, corpus slow waves were recorded and mapped (frequency 2.7 ± 0.03 cycles per minute, amplitude 0.8 ± 0.4 mV, velocity 2.3 ± 0.9 mm s(-1)). In conclusion, the novel laparoscopic device achieves high-quality serosal slow wave recordings. It can be used for laparoscopic diagnostic studies to document slow wave patterns in patients with gastric motility disorders.