Left upper quadrant laparoscopic placement: effects of insertion angle and body mass index on distance to posterior peritoneum by magnetic resonance imaging.

Abstract

To determine the ideal angle for insertion of laparoscopic instruments at Palmer's point. Abdominal magnetic resonance images were reviewed for 75 women between ages 18 and 50 years old. The distance from the skin to the retroperitoneal structures were determined perpendicular to the spine and angled 45 degrees caudally. When instruments are inserted perpendicular to the skin in the axial plane and peritoneum perpendicular to the spine, the distance from skin to posterior was 10.0 +/- 0.2 cm and to the aorta was 11.3 +/- 0.2 cm. If instruments are inserted at an angle 45 degrees caudally, this distance increased to 16.6 +/- 0.2 cm. When inserting laparoscopic instruments at Palmer's point, insertion perpendicular to the skin in the axial plane and angled 45 degrees caudally in relation to the spine offers an increased margin of safety compared with insertion perpendicular to the spine, particularly in thin women.