2012 Proceedings - International Tissue Elasticity Conference

088 TISSUE ELASTICITY AS A MARKER OF PELVIC FLOOR CONDITIONS: CLINICAL RESULTS.
Heather van Raalte 1 , Vladimir Egorov 2 , Vincent Lucente 3 .
1 Princeton Urogynecology, 601 Ewing Street, Suite B–19, Princeton, NJ 08540, USA; 2 Artann
Laboratories, 1459 Lower Ferry Rd., Trenton, NJ 08618, USA; 3 The Institute for Female Pelvic
Medicine and Reconstructive Surgery, 3050 Hamilton Blvd, Suite 200, Allentown, PA 18104, USA.
Background: Changes in the elasticity of vaginal walls, connective support tissues and muscles are
thought to be significant factors in the development of pelvic organ disorders. Previously, we clinically
tested the Vaginal Tactile Imager (VTI) which has allowed imaging of the vagina at specified locations and
an assessment of the associated tissue elasticity [1,2]. The 3–D vaginal tactile image is a spatial scalar
map of stress data (pressures) acquired at a surface of vaginal wall under deformation resulting from
applied transvaginal probe with pressure sensors.
Aims: The objective of this study is to estimate ranges of normality for tissue elasticity of vagina and its
support structures by means of 3–D tactile imaging.
Methods: This is sub–analysis of the dataset of 57 women recruited for clinical studies. The dataset
included 32 women with normal pelvic support and 25 women with pelvic organ prolapse (Stage I–III),
average age 59±18 from 21 to 90 years old. Transvaginal probe included pressure sensor array and six
degree–of–freedom motion tracking sensor. A standard physical examination was performed by an
urogynecologist to characterize pelvic floor conditions. The tissue elasticity (Young’s modulus) was
calculated from spatial gradients in resulting 3–D tactile image. The vaginal wall deformations were in the
range from 5 to 40mm depending on the tissue elasticity under the probe with the applied force not
exceeding 10N.
Results: Figure 1 presents a typical example of tactile imaging for normal pelvic floor conditions. The four
rectangles in the sagittal plane (Figure 1) at apical and mid–vagina anterior and posterior compartments
show areas used for tissue elasticity calculations. Two axial tactile planes in Figure 1 also contain areas
for tissue elasticity calculation. We found for normal pelvic support the ranges for tissue elasticity
(Young’s modulus, kPa) for apical anterior [4.2; 16], apical posterior [3.8; 18], mid anterior [6.0; 25], mid
posterior [8.0; 34], and mid lateral vaginal walls [7; 27]. The elasticity values calculated at the mid lateral
vaginal walls might be related to the conditions of underlying puborectalis, levator ani and obturator
internus muscles, calculated at mid posterior to the rectovaginal fascia and perineal body, apical
posterior elasticity to the uterosacral ligaments, anterior elasticity to vesical and pubocervical fascia. We
estimated an average value of tissue elasticity for anterior and posterior under prolapse conditions as
2.5±1.1kPa.
Conclusions: Our findings suggest that the normality ranges for tissue elasticity of vagina and its
support structures evaluated by VTI might be used as the markers in diagnosis of pelvic floor conditions.
Conclusions: Our findings suggest that the normality ranges for tissue elasticity of vagina and its
support structures evaluated by VTI might be used as the markers in diagnosis of pelvic floor conditions.
Acknowledgements: NIH/NIA Grant AG034714.
References:
[1] IEEE Trans. Biomed. Eng., 57(7), pp. 1736–44; 2010
[2] Int. Urogynecology J., 23(4), pp. 459–66, 2012.
Figure 1: Two axial (mid and apical from left to right), and saggital cross–sections of 3–D vaginal tactile image
received with VTI for a patient (53 y.o.) with normal pelvic floor condition as was found by physical
examination. Young’s modulus was calculated for areas specified by a rectangle.
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