Subscribe to RSS
DOI: 10.1055/s-0031-1286490
Levato-Anal Angle: A new Method to assess the Position of the Ani
Fragestellung: Our aim was to establish a reproducible method to evaluate the angle of the anal canal in respect to the hiatus genitalis using 2D perineal ultrasound; we assessed also if levator trauma modifies the angle and the mobility of the anal canal 1-year postpartum.
Methode: Primiparous women who delivered vaginally in our department between January-June 2009 and with 3D ultrasound diagnosis of LAM trauma on 2nd-3rd day postpartum confirmed 1-year later, were included in the cases. The controls were represented by women with the same criteria of eligibility but with intact LAM. The anal canal forms an acute angle with the plane of minimal hiatal dimension opened dorsally: this Levato-Anal-Angle (LAA) (Fig.1) was measured with 2D perineal ultrasound by placing as landmarks a line at the plane of minimal hiatal and a line through the hypoechoic band representing the posterior internal anal sphincter, at rest and during Valsalva.
Ergebnisse: Forty patients were included in our trial, 20 with and 20 without levator trauma. With a correlation coefficient of 0.79, the relationship between the two observers' measurements resulted very good-excellent (Colton rules). The LAA is larger in the cases, both at rest and during Valsalva maneuver, for both the assessors, but the difference did not reach statistical significance (Pv=0.62 and Pv=0.27 Observer 1, Pv=0.13 and Pv=0.29 Observer 2, respectively) (Tab.1). Also the mobility of the anal canal (evaluated as difference between LAA at rest and LAA during Valsalva: Δ LAA) resulted smaller in the levator trauma group without reaching statistical significance (Pv=0.35 Observer 1, Pv=0.30 Observer 2) (Tab.2).
Schlussfolgerung: This study introduces a new reproducible parameter to evaluate the angle of the anal canal in respect to the pelvic floor structures. From our results, 1-year postpartum levator trauma does not seem to affect angulation and mobility of the anal canal.
|
Women with LAM defect (n=20) |
Women without LAM defect (n=20) |
Pv |
|
|
LAA rest – Observer 1 (degree) |
52.4 (±9.8) |
50.9 (±8.0) |
0.62° |
|
LAA rest – Observer 2 (degree) |
58.9 (±13.86) |
52.68 (±8.0) |
0.13° |
|
LAA Valsalva – Observer 1 (degree) |
45.48 (±9.3) |
41.8 (±11.47) |
0.27° |
|
LAA Valsalva – Observer 2 (degree) |
43.33 (25.55–85.56) |
40.75 (14.9–72.4) |
0.29* |
|
Women with LAM defect (n=20) |
Women without LAM defect (n=20) |
Pv |
|
|
Δ LAA Observer 1 |
8 (0.8–33.08) |
9.2 (1.1–22.82) |
0.35* |
|
Δ LAA Observer 2 |
10.84 (±5.8) |
12.94 (±8.2) |
0.30° |
Data are expressed as median (range), mean±standard deviation.
° t-test Student;
*Mann-Withney test
Figure 1: Levato-Anal-Angle (LAA) The Levato-Anal Angle (LAA) corresponds to the acute angle between the plane of minimal hiatal dimensions and a line through the hypoechoic band representing the posterior internal anal sphincter.