Study Finds New MRI Technique for Pelvic Organ Prolapse Assessment

The findings were published online in the American Journal of Obstetrics and Gynecology.

Pelvic magnetic resonance imaging (MRI) is widely used to assess the extent of pelvic organ prolapse, with the pubococcygeal line serving as a standard reference. However, this traditional method only measures the three lowest points in the anterior, middle, and posterior compartments, overlooking other pelvic floor structures and their interactions.

To overcome this limitation, Jiajia Luo, Institute of Medical Technology, Peking University Health Science Center, Beijing, China, and colleagues introduced a novel approach—the area under the pubococcygeal line—as a more comprehensive measurement. The aim was to validate this method by examining its correlation with clinical Pelvic Organ Prolapse Quantification (POP-Q) staging and to assess its reliability across different raters.

For this purpose, the researchers recruited 225 women who underwent magnetic resonance imaging measurements and clinical Pelvic Organ Prolapse Quantification staging. To assess the applicability and reliability of the area under the pubococcygeal line measurement, they employed a comprehensive statistical approach that included descriptive analysis, correlation analysis, reliability assessment, and ordinal logistic regression analysis.

The following were the key findings of the study:

• Higher values of the area under the pubococcygeal line were linked to more severe stages of pelvic organ prolapse.
• The area under the pubococcygeal line showed a strong positive correlation with clinical prolapse staging (Spearman’s r = 0.878), performing better than traditional pubococcygeal line grades (Spearman’s r = 0.777).
• The new measurement method demonstrated excellent consistency, with high intra- and interrater reliability (intraclass correlation coefficients of 0.980 and 0.906, respectively).
• Ordinal logistic regression analysis confirmed a significant association between the area under the pubococcygeal line and the severity of pelvic organ prolapse.

The area under the pubococcygeal line (AUPCL) represents a novel and comprehensive MRI-based measurement technique for evaluating pelvic organ prolapse. By encompassing all key pelvic floor structures, it shows a strong correlation with clinical POP-Q staging and demonstrates excellent reliability across different raters.

"With its potential to improve diagnostic accuracy and support more tailored treatment decisions, the AUPCL may serve as a valuable complement to existing assessment methods in the clinical management of pelvic organ prolapse," the authors concluded.

Reference:

Zhang, C., Li, X., Xie, B., Gao, L., Feng, Y., Sun, X., Luo, J., & Wang, J. (2025). A novel pelvic magnetic resonance imaging measurement for pelvic organ prolapse evaluation. American Journal of Obstetrics and Gynecology, 232(4), 383.e1-383.e8. https://doi.org/10.1016/j.ajog.2024.10.007