1739 Ultrasound Elastography for Gynecological Applications: Preliminary Reliability Analysis

Abstract

Study Objective This preliminary investigation aimed to evaluate the feasibility of using ultrasound elastography (UE) to evaluate the myometrial and uterine leiomyoma stiffness. Our objectives were to (1) assess the reliability of UE stiffness measures of non-neoplastic myometrium, and (2) compare UE stiffness measures of non-neoplastic myometrium and leiomyomas. Design This preliminary investigation used a prospective, observational design. Setting Motor Function Measurement Laboratory at the University of Ottawa. Patients or Participants Nine healthy women with no gynecologic history (control) and one woman (case) with two asymptomatic uterine leiomyomas (FIGO 6) were recruited from the local community. Interventions Three trials of a 2D UE cineloops were acquired transvaginally (Aixplorer, SuperSonic Imagine) at the frontal midsagittal myometrium and in the sagittal plane of each leiomyoma. The procedure was repeated twice at the first visit (V1S1, V1S2) and again 2-3 days later (V2S1). Participants completed the menstrual bleeding questionnaire (MBQ) at V1S1. Measurements and Main Results Descriptive statistics were used to evaluate normative peak myometrial stiffness, and the reliability of peak tissue stiffness (kPa), averaged across three trials (10 frames/trial), was evaluated using intraclass correlation coefficients (ICCs). The control group (age=30.2±4.4 years, MBQ=11±9) had median parity of 0 (range: 0-1), while the case participant (age=31.4 years, MBQ=13) had parity of one. Peak myometrial tissue stiffness (V1S1=35.9±9.6 kPa, V1S2=34.1±8.8kPa, V2S1=32.7±11.9kPa) exhibited excellent within-session reliability (ICCV1S1=0.89, ICCV1S2=0.92, ICCV2S1=0.96), and good between-session (ICC=0.71) and between-day (ICC=0.76) reliability. The 95% prediction interval for normative myometrial tissue, computed using values recorded from the control group was 18.5-50.0kPa. The peak stiffness of both leiomyomas (Fibroid A = 111.4kPa; Fibroid B = 84.0kPa) well exceeded the 95% prediction interval for unaffected myometrium. Conclusion UE stiffness exhibited good to excellent reliability in non-neoplastic myometrial tissue, and much higher stiffness was observed in the two asymptomatic fibroids, suggesting that UE may have clinical value in this gynecologic population.