Comparison of translabial three-dimensional ultrasound with magnetic resonance imaging for measurement of levator hiatal biometry at rest

Relationship between pelvic floor muscle function and insulin resistance among non-diabetic females: a 3d ultrasound evaluation

BACKGROUND

To use the three-dimensional (3D) ultrasound for assessment of pelvic floor muscle function in non-diabetic females with insulin resistance (IR), and to evaluate its functional relationship with insulin levels.

METHODS

From October 2022 to November 2023, 216 non-diabetic females with insulin-resistant (IR group) and 118 normal females (control group) were sequentially recruited from our hospital for our study. The 3D ultrasound was used to assess the levator hiatus in resting state for all females regarding diameter lines, perimeters and areas; as well as the Valsalva manoeuvre (VM). The t-test and linear regression model were used to analyse the collected data.

RESULTS

The analysis indicates that there were significant differences in the resting state of the levator hiatus between the IR and the control groups (14.8 ± 5.8 cm2 and 11.6 ± 2.7 cm2, p < 0.05); and in the VM (18.2 ± 6.3 cm2 and 13.4 ± 3. 4 cm2, p < 0.05). In addition, the anterior-posterior (AP) diameters of the hiatus on VM were significantly increased in the IR group (40.0 ± 4.7 mm and 33.0 ± 4.4 mm, p < 0.05). With insulin levels as the dependent variable, multivariate regression analysis shows that insulin levels were significantly correlated with the levator hiatus area on VM (p < 0.05) and waist circumference (p < 0.05). The pelvic organ descent on VM in the IR group was significant (p < 0.05).

CONCLUSIONS

The areas of resting state levator hiatus and on VM were significantly larger in the IR than that in the control groups. In addition, the position of the pelvic organ on VM in the IR group was significantly descended. The insulin levels were correlated with the pelvic floor muscle function.

Diagnostic test accuracy of magnetic resonance imaging and pelvic floor ultrasound for diagnosis of levator ani muscle avulsion

OBJECTIVE

To estimate the diagnostic test accuracy of magnetic resonance imaging (MRI) and pelvic floor ultrasound for levator ani muscle (LAM) avulsion in a general parous population, with view to establishing if ultrasound could substitute for MRI to diagnose LAM avulsion.

METHODS

This was a cross-sectional study of 135 women 4 years after their first delivery. Signs and symptoms of pelvic floor dysfunction were assessed using validated methods. All women underwent four-dimensional transperineal ultrasound (TPUS), three-dimensional endovaginal ultrasound (EVUS) and MRI. Images were acquired at rest, on pelvic floor muscle contraction (PFMC) and on maximum Valsalva maneuver, and analyzed by two blinded observers. Predefined cut-off values were used to diagnose LAM avulsion. In the absence of a reference standard, latent class analysis (LCA) was used to establish diagnostic test characteristics for LAM avulsion as the primary outcome measure. Secondary outcomes were kappa (κ) agreement between imaging techniques, intraclass correlation coefficients (ICC) for hiatal measurements at rest, on PFMC and on maximum Valsalva maneuver, and the association of LAM avulsion with signs and symptoms of pelvic floor dysfunction.

RESULTS

The prevalence of LAM avulsion was 23.0% for MRI, 11.1% for TPUS and 17.8% for EVUS. The prevalence of LAM avulsion using LCA was 15.7%. The sensitivity for LAM avulsion of TPUS (71% (95% CI, 50-90%)) and EVUS (91% (95% CI, 74-100%)) was lower than that of MRI (100% (95% CI, 84-100%)). The specificity of TPUS (100% (95% CI, 97-100%)) and EVUS (95% (95% CI, 91-99%)) was higher than that of MRI (91% (95% CI, 85-97%)). MRI and EVUS had high predictive values for the assessment of major LAM avulsion (positive predictive value (PPV), 95% and negative predictive value (NPV), 100%; PPV, 100% and NPV, 98%, respectively), while TPUS had high predictive values for minor LAM avulsion (PPV, 100% and NPV, 95%). Major LAM avulsion on MRI and EVUS was associated with anterior vaginal wall prolapse, which was not found for TPUS. The agreement in the diagnosis of LAM avulsion (κ, 0.69) and hiatal measurements (ICC, 0.60-0.81) was highest between MRI and EVUS.

CONCLUSIONS

Pelvic floor ultrasound can be implemented as a triage test to assess parous women for LAM avulsion because of its high specificity. Ultrasound cannot substitute for MRI because of its lower sensitivity. The predictive ability of ultrasound is moderate for the presence, and very good for the absence, of LAM avulsion. A positive test should be confirmed by a different observer or imaging technique. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.