Digital examination compared to trans-perineal ultrasound for the evaluation of anal sphincter repair.

OBJECTIVE

To assess the adequacy of a third- or a fourth-degree laceration repair by comparing digital and trans-perineal ultrasound measurements.

METHOD: During a 4-year period, 34 subjects without prior history of anal sphincter injury or fecal incontinence underwent ultrasound measurements of external anal sphincter muscle diameter and perineal length, which were compared to measurements obtained by digital examination.

RESULTS

Pearson's correlation coefficients for comparing the digital external sphincter examination to trans-perineal ultrasonography, and the digital perineal examination to trans-perineal ultrasonography were 0.88 and 0.40, respectively. Patients (n=4/34) whose external sphincter was identified as less than 1 cm by digital examination were found to have an external sphincter diameter of less than 1 cm by trans-perineal ultrasound.

CONCLUSION

The digital perineum examination is a reliable method of measuring the external sphincter thickness and perineal body length immediately after primary repair.