DISCREPANCIES IN ANAL MANOMETRIC PRESSURE MEASUREMENT - IMPORTANT OR INCONSEQUENTIAL

PURPOSE: Maximum resting and squeeze pressures have been the most wide ly employed parameters for manometric assessment of the anal sphincter s. However, a single maximum value may not always be the best assessme nt. METHODS: The aim of this study was to compare mean and maximum res ting and mean and maximum squeeze pressures in a large sample populati on. All manometric pressure profiles were reviewed by a single individ ual blinded to the patient's age and diagnosis. RESULTS: Four hundred sixty-six patients with a measurable high-pressure zone were included in this study. The study population was comprised of 279 females and 1 86 males. A significant difference was found between mean (56.26 mmHg) and maximum (79.2 mmHg) resting pressures (P < 0.01) and also bern ee n mean (81.25 mmHg) and maximum (119.50 mmHg) squeeze pressures (P < 0 .01). A significant difference (P < 0.01) was also observed when compa red by length of the high-pressure zone. CONCLUSION: The measurement, documentation, and reporting of mean resting and mean squeeze pressure s provide a better perspective of anal manometric results, since the t wo sets of values are significantly different (P < 0.01), regardless o f the anal canal length. Therefore, these data support the standardize d evaluation of both mean and maximum pressures in individual patients and in published series.