Role of three-dimensional endoanal ultrasound in assessing the anal sphincter morphology of female patients with chronic proctalgia

Figure 1 Internal anal sphincter thickness is defined as the mean thickness of the internal anal sphincter at 12, 3, 6, 9 o’clock positions in the mid-axial plane. IAS: Internal anal sphincter; EAS: External anal sphincter.

Figure 2 The Internal anal sphincter length (solid line) and the length of external anal sphincter plus puborectalis muscle (dotted line) were measured in the mid-sagittal plane. IAS: Internal anal sphincter; EAS: External anal sphincter; PR: Puborectalis muscle.

Figure 3 Thickness of puborectalis muscle was measured in the distal-axial plane (solid line). PR: Puborectalis muscle.

Figure 4 Puborectalis angle (α angle). IAS: Internal anal sphincter; EAS: External anal sphincter; PR: Puborectalis muscle.

Figure 5 Puborectalis angle during resting phase (A) and straining phase (B) in chronic proctalgia and normal control groups (P < 0. 05). CP: Chronic proctalgia.

Figure 6 Puborectalis angle during resting and straining phases in the chronic proctalgia group (A) (P > 0. 05) and normal control group (B) (P < 0.05). CP: Chronic proctalgia.