Positional anatomy of vessels that may be damaged at laparoscopy: new access criteria based on CT and ultrasonography to avoid vascular injury.

BACKGROUND AND PURPOSE

To study the relations of major blood vessels (aortoiliac bifurcation and iliocaval confluence) and the inferior epigastric arteries to the umbilicus and the anterior superior iliac spine (ASIS) planes and to apply this information to define ideal, anatomically based locations for primary and secondary laparoscopic port insertions to minimize vascular injuries.

MATERIALS AND METHODS

Two hundred randomly selected postcontrast CT images of the abdomen and pelvis were assessed by two radiologists. The position of the umbilicus (mobile point), ASIS (fixed point), and relations with the great vessels were measured. The angle of the umbilicus with the aortic bifurcation, theta (theta), was calculated using trigonometric principles. The position and course of the inferior epigastric arteries (IEA) was analyzed in 103 patients with color Doppler ultrasonography.

RESULTS

The median distance of the aortoiliac bifurcation was 8 mm (interquartile range [IQR] 28.8 mm] and that of the iliocaval venous confluence 25 mm (IQR 32 mm) below the umbilicus. The aorta divided 48 mm (IQR 16 mm) and the iliac veins joined 33 mm (IQR 9 mm) above the ASIS plane. The angle of the umbilicus to the aortoiliac bifurcation in the sagittal plane had a range of 14 degrees to 34 degrees with a median of 21.6 degrees . The median distance from the right IEA to the midline at the umbilicus was 4.75 cm (IQR 0.7 cm), and the same distance in the ASIS plane was 4.8 cm (IQR 0.7 cm). The distance of the IEA to the midline did not exceed 6 cm in any patient on either side or in either plane.

CONCLUSION

The position of the umbilicus should not be relied on for access planning. The relation between the level of the ASIS and the aortic bifurcation is more consistent. The ideal primary port entry (or Veress needle site) is at the ASIS plane in the midline, and the ideal lateral port entry is in the same plane >6 cm from the midline. If the umbilicus is to be used, a Hasson insertion is desirable, but if a Veress needle is used at the umbilicus, an angle of 45 degrees in the sagittal plane should be used.