Fine Tilt Tuning of a Laparoscopic Camera by Local Magnetic Actuation: Two-Port Nephrectomy Experience on Human Cadavers

Abstract

BACKGROUND: The magnetic surgical camera is an emerging technology having the potential to improve visualization without taking up port site space. However, tilting the point of view downward/upward can be done only by constantly applying a pressure on the abdomen. This study aims to test the hypothesis that the novel concept of local magnetic actuation (LMA) is able to increase the tilt range available for a magnetic camera without the need for deforming the abdominal wall. The hypothesis that 2-port laparoscopic nephrectomy in fresh tissue human cadavers could be performed by using the LMA camera is also tested.

METHODS: First, the 2 cameras were separately inserted, anchored, and moved inside the inflated abdomen. Tilting angles were quantified by image analysis while intra-abdominal pressure changes were monitored. Then, 5 two-port nephrectomies were performed by using the LMA camera while collecting quantitative outcomes.

RESULTS: The magnetic camera required a constant pressure on the magnetic handle to achieve an average ±20° tilt from the horizontal position, with an average of 7 mm Hg loss of intra-abdominal pressure. The LMA camera allowed for 75° of tilt from the horizontal position with a resolution of ±1°, without any need to deform the abdomen. All the nephrectomies were completed successfully within an average time of 11 minutes.

CONCLUSION: LMA is an effective strategy to provide magnetic cameras with wide-range and high-resolution vertical motion without the need to deform the abdominal wall.