Which test is most appropriate to quantify anorectal sensation, resting and squeeze pressure and length of the anal canal?

Which test is most appropriate to quantify anorectal sensation, resting and squeeze pressure and length of the anal canal?

• A. Defecography
• B. Anal electromyography
• C. Anorectal manometry
• D. Endoanal ultrasound

Answer: (C)

Measuring anorectal pressures and sensation is best accomplished with anorectal manometry. It uses a pressure-sensing catheter to quantify resting and squeeze pressures and to map the pressure along the anal canal, from which the canal length can be inferred. It also assesses anorectal sensation by balloon distension to determine sensory thresholds. Other tests don’t provide this combined functional data: defecography shows defecation dynamics and anatomy, anal electromyography records muscle electrical activity, and endoanal ultrasound images sphincter structure.

Measuring anorectal pressures and sensation is best accomplished with anorectal manometry. It uses a pressure-sensing catheter to quantify resting and squeeze pressures and to map the pressure along the anal canal, from which the canal length can be inferred. It also assesses anorectal sensation by balloon distension to determine sensory thresholds. Other tests don’t provide this combined functional data: defecography shows defecation dynamics and anatomy, anal electromyography records muscle electrical activity, and endoanal ultrasound images sphincter structure.