Vaginal tactile imaging

Abstract

Changes in the elasticity of the vaginal walls, connective support tissues, and muscles are thought to be significant factors in the development of pelvic organ prolapse, a highly prevalent condition affecting at least 50% of women in the United States during their lifetimes. It creates two predominant concerns specific to the biomechanical properties of pelvic support tissues: how does tissue elasticity affect the development of pelvic organ prolapse and how can functional elasticity be maintained through reconstructive surgery. We designed a prototype of vaginal tactile imager (VTI) for visualization and assessment of elastic properties of pelvic floor tissues. In this paper, we analyze applicability of tactile imaging for evaluation of reconstructive surgery results and characterization of normal and pelvic organ prolapse conditions. A pilot clinical study with 13 patients demonstrated that VTI allows imaging of vaginal walls with increased rigidity due to implanted mesh grafts following reconstructive pelvic surgery and VTI has the potential for prolapse characterization and detection.

Figures

Fig. 1

Tactile sensor array mounted on the tip of the VTI probe allows recording the stress patterns on the vaginal walls under manually applied pressure as a function of the angular position of the probe detected by the orientation sensor.

Fig. 2

Physician examination sheet for case 1.

Fig. 3

Tactile imaging of anterior and posterior vaginal walls allows visualization and quantitative elasticity evaluation of increased rigidity at both mesh grafts.

Fig. 4

Physician examination sheet for case 2.

Fig. 5

Loading curves obtained in case 2 examination (see text). The slope (Es) of the scanhead applied force versus elevation angle of the probe characterizes an elasticity of the vaginal wall against which the scanhead has been pressed.

Fig. 6

Physician examination sheet for case 3.

Fig. 7

Loading curves obtained in case 3 examination (see text). The slope (Es) of applied force versus elevation angle is the elasticity index characterizing elastic properties of the vaginal wall.

Fig. 8

Anterior vaginal wall elasticity index (Es) measured by VTI versus patient vaginal anterior condition from normal to prolapse (Grades 1–3) evaluated by physical examination.

Fig. 9

Posterior vaginal wall elasticity index (Es) measured by VTI versus patient vaginal posterior condition from normal to prolapse (Grades 1–3) evaluated by physical examination.

Fig. 10

Box plots demonstrating discrimination of normal from prolapse vaginal wall conditions assessed by VTI.