Uterine Position and Diagnostic Accuracy of Transvaginal 2D, 3D, Transrectal and Transabdominal Ultrasonography in the Assessment of Endometrial and Uterine Cavity Abnormalities-A Narrative Review.

Transvaginal ultrasound (TVS) remains the most frequently performed examination in gynecological patients to evaluate the uterine cavity. Visualization of the endometrium may be limited due to certain uterine positions, particularly axial and retroverted orientations. Alternative diagnostic methods, such as transabdominal ultrasound (TAS) and transrectal ultrasound (TRS), may be useful in patients in whom visualization is suboptimal using the TVS. The aim of the study was to analyze the literature regarding the diagnostic performance of TVS, TAS, and TRS in detecting uterine cavity abnormalities in women with various uterine positions. Studies evaluating ultrasound assessment of uterine cavity pathologies with reference to uterine position were included in this review. The available research suggests that uterine position may influence ultrasound visualization. TAS has been shown to demonstrate lower diagnostic reliability in retroverted or axial uteri, particularly in patients with obesity or when focal lesions are present. TRS may provide improved assessment of endometrial thickness in patients with axial uteri compared with TVS. Uterine position may be a factor affecting the accuracy of evaluation of the uterine cavity in ultrasound. Awareness of these limitations and the use of additional imaging modalities may improve diagnostic accuracy in selected patients. Further studies are needed.