A novel pelvic magnetic resonance imaging measurement for pelvic organ prolapse evaluation

Background: Pelvic magnetic resonance imaging has been proven effective for quantifying the extent of prolapse. The pubococcygeal line is used universally as a reference line in measuring pelvic organ prolapse, however, it focuses solely on three lowest points in the anterior, middle, and posterior pelvic compartments, without taking into account other pelvic floor structures and their interactions.

Objectives: This study aimed to introduce and validate the area under the pubococcygeal line, a novel measurement method for evaluating pelvic organ prolapse, to examine its correlation with clinical Pelvic Organ Prolapse Quantification staging, and assess its reliability across different raters.

Study design: This study recruited 225 women who underwent evaluations involving both magnetic resonance imaging measurements and clinical Pelvic Organ Prolapse Quantification staging. A comprehensive statistical approach involving descriptive analysis, correlation analysis, reliability assessment, and ordinal logistic regression analysis was adopted to evaluate the applicability and reliability of the area under the pubococcygeal line measurement.

Results: Analysis of participant characteristics across different POP-Q stages revealed a significant association between increased values of the area under the pubococcygeal line and severity of Pelvic Organ Prolapse Quantification staging. Correlation analysis was performed to identify and quantify the strength of the associations between the variables. The area under the pubococcygeal line showed a strong positive correlation with Pelvic Organ Prolapse Quantification stages (Spearman's r = 0.878, p < 0.001), outperforming the pubococcygeal line grades (Spearman's r = 0.777, p < 0.001). Reliability assessments yielded excellent intra- and inter-rater reliability, with intraclass correlation coefficient values of 0.980 and 0.906, respectively. Ordinal logistic regression analysis was used to determine the association between these variables and POP severity, highlighting significant associations between the area under the pubococcygeal line and Pelvic Organ Prolapse Quantification stages.

Conclusion: The area under the pubococcygeal line measurement method is a novel and comprehensive magnetic resonance imaging technique for evaluating pelvic organ prolapse. This method strongly correlates with clinical Pelvic Organ Prolapse Quantification stages and exhibits excellent intra- and inter-rater reliability, holding a potential for enhanced diagnostic accuracy, optimized treatment strategies, and improved patient outcomes.