Three-dimensional high-resolution anorectal manometry and diagnosis of excessive perineal descent: a comparative pilot study with defaecography

Aim Three-dimensional high-resolution anorectal manometry (3DHRAM) is a new technique that can simultaneously provide physiological and topographical data on the terminal part of the digestive tract. Our object was to assess whether 3DHRAM is able to reliably diagnose excessive perineal descent already diagnosed with conventional defaecography, which is considered to be the gold standard. Method All patients referred to our centre for anorectal manometry and conventional defaecography were evaluated with a maximum of 6 months between the two examinations. Anorectal manometry was performed using the 3D High-Resolution Given Imaging® probe. Excessive perineal descent was defined as the downward movement of the anal high-pressure zone during straining. At the end of the straining effort, the high-pressure zone regained its initial position, thereby indicating that the probe had not moved. Results Nineteen female patients of median age 53 (21–70) years were included in the study. All cases with excessive perineal descent diagnosed using defaecography were visualized with 3DHRAM. The degree of perineal descent determined by 3D and conventional defaecography was compared (Spearman correlation 0.726, P = 0.01). In contrast, the averages measured were significantly different; the average was 11.68 ± 3.3 mm for 3DHRAM but 34.21 ± 13.3 mm for conventional defaecography (P = 0.002). Conclusion The results of the study demonstrate that 3DHRAM can diagnose excessive perineal descent with the same degree of reliability as defaecography. Quantitative measures were not correlated, however, possibly because of methodological differences. The study confirms the value of the morphological data provided by 3DHRAM.