How to determine "ballooning" of the levator hiatus on clinical examination: a retrospective observational study

Introduction and hypothesis: Dimensions of the levator hiatus determined on imaging are strong predictors of symptoms and signs of female pelvic organ prolapse (FPOP) and of FPOP recurrence. A clinical equivalence can be recorded as genital hiatus (Gh) + perineal body (Pb) using the ICS prolapse quantification system. The objective of this study was to stratify the Gh+Pb measurement to provide clinicians with clinical diagnostic criteria similar to those available on imaging. Methods: A retrospective study of the data sets of 477 patients seen in a tertiary urogynecological clinic. Results: On average, Gh was 4.2 (range, 1.5-8.5) cm, Pb 3.8 (range, 2.0-7.0) cm, Gh+Pb 7.9 cm (range, 4.2-13.0). The sum of Gh+Pb was strongly associated with symptoms (p < 0.001) and signs (p < 0.001) of FPOP. On receiver-operator characteristic statistics, the area under the curve was determined as 0.707 (0.658-0.755) in predicting symptoms of FPOP, and as 0.890 (0.854-0.925) for predicting FPOP ≥ stage 2, using 7 cm as the optimal cut-off for Gh+Pb. Using the data sets of 309 patients with abnormal (i.e. ≥7 cm) Gh+Pb measurements, we stratified abnormal hiatal distensibility, or "ballooning", into mild, moderate, marked and severe as Gh+Pb = 7.0-7.99 cm, 8.0-8.99 cm, 9.0-9.99 cm and 10 cm or more respectively, as the optimal compromise between easily remembered cut-off numbers and quartiles. Conclusions: The sum of Gh+Pb measurement may allow clinicians to determine the degree of excessive hiatal distensibility or 'ballooning' without requiring imaging assessment.