VP64.12: Which is the best parameter and its cut‐off value to diagnose a t‐shaped uterus by 3D TVS?

To assess which uterine parameter is more reliable and accurate to distinguish between ESHRE-ESGE normal (class U0) and t-shaped (class U1a) uterus and its best cut-off value. Consecutive fertile patients with t-shaped uterus were recruited and compared to a control group (normal uterus). Patients with myomas and/or adenomyosis were excluded. 3D-TVS was performed by the GE Voluson E8 unit, using a wide-band 3-9 MHz transducer. Compound resolution imaging (CRI) and speckle-reduction imaging (SRI) technologies were used to optimise image before volume acquisition by enhancing contrast resolution and reducing artifacts and speckle. Volume contrast imaging (VCI) analysis (by two millimetres slices) of the stored 3D multiplanar examination was considered for the evaluation of the lateral (L) and the anteroposterior (AP) uterine wall thickness and their ratio (L/AP) on the sagittal and coronal planes. The uterine wall thickness was measured at its thickest in the orthogonal planes. The area under the receiver-operating characteristics curve (AUC) was used to estimate diagnostic test accuracy and Youden's index was used to find the best cut-off value. Sensitivity, specificity, negative- and positive-likelihood ratio (LR- and LR+) were calculated. 310 enrolled patients were considered (215 and 95 class U0 and U2 patients, respectively). Mean age was 33 years (SD ± 7). Mean L thickness was significantly thicker in the t-shaped compared to the normal uterus (19.5 ± 2.4mm vs 13.4 ± 1.4mm, respectively). Mean L/AP ratio was significantly higher in the t-shaped compared to the normal uterus (t-shaped 1.5 ± 0.2mm vs 1.1 ± 0.1mm). The best strict, proper and reproducible diagnostic parameter to diagnose t-shaped uterus is the assessment of the lateral thickness on the coronal plane. The best cut-off value is 16.5mm.