Anorectal manometry: what it is used for and how it is performed - THDLAB - COM

  • Anorectal manometry: what it is for
  • Anorectal manometry: preparation
  • Traditional anorectal manometry: how it is performed
  • Evolution of anorectal manometry test: features and advantages

Anorectal manometry: what it is for

Anorectal manometry is an exam used to evaluate problems in the functioning of anal sphincters. This exam is also useful for furthering the diagnosis of numerous anorectal disorders.

Anorectal manometry is also used for the pre and/or post-operative evaluation of operations in the anorectal area. In several cases these operations can in fact entail risks for anal continence.

Through the manometry, the doctor measures the pressure of the sphincters during evacuation, at rest or during contraction. In this way the specialist can assess the ability to manage the passage of liquid and solid stools or intestinal gases. These assessments are made taking into account gender, age, childbirths and other diseases.

During evacuation, the sphincter muscles must relax to allow the passage of faeces and gases. On the contrary, to postpone evacuation, the sphincters must contract sufficiently.

It is also important that the sphincters should exert the right pressure even at rest to avoid involuntary leaks during sleep or when coughing. Any element capable of altering these mechanisms can have an impact on continence.

The accurate diagnosis of sphincter disorders is therefore fundamental to define the therapeutic procedure.

Through anal manometry it is possible to objectively study the overall functionality of the sphincters. The doctor evaluates the sphincters during evacuation, at rest and during contraction and identifies any anomalies. In particular, manometry enables identifying:

  • incontinence problems linked to the inability of the sphincter muscles to contract properly
  • difficulty in defecation due to incomplete opening and release of the sphincter muscles

To date there are no alternative diagnostic exams to anorectal manometry to obtain this type of data. For this reason, in the case of symptoms due to alterations in the functioning of anal sphincters, anorectal manometry is a fundamental test.


Anorectal manometry: preparation

To prepare for the exam, the doctor may request an enema to be performed. Manometry generally takes place in the clinic and does not require anaesthesia. Fasting, suspension of any on-going therapies or dietary changes during the days before are not required. The patient can go to the exam alone as a manometry does not involve administering any drug.


Traditional anorectal manometry: how it is performed

Classic manometry is an outpatient examination used to examine the mechanisms of evacuation and of faeces containment. The examination is carried out using a water or air perfusion system, specific catheters and a data acquisition system.

The patient lies on his/her left side, brings his/her knees close to the chest and rests his/her buttocks on the edge of the couch (Sims position). The specialist then introduces a catheter on which there is a small balloon into the anal canal up to the rectal ampulla. At this point the doctor blows the fluid inside the balloon to dilate the anorectal canal. Dilation simulates the sensation of relaxation and of stimulation to evacuate typical of defecation.

The doctor can then detect the pressure exerted by the patient in different points of the anorectal canal and identify the causes of disorders such as incontinence and sphincter hypertonia.


Evolution of anorectal manometry test: features and advantages

Recent technological innovations have led to an evolution in classical anorectal manometry test. Equipment is now available which allows manometry to be carried out effectively and with greater comfort for the patient.

In an increasing number of medical centres, anorectal manometry is performed by means of a small, highly sensitive probe. The probe is connected to a portable device which allows to measure pressure variations in real time and to record these. The examination lasts no more than 5 minutes: waiting times are therefore drastically reduced and the discomfort perceived by the patient is minimal.

Clinics which use this new diagnostic system are greatly on the increase, thanks to its precision and ease of execution and interpretation of the data. This allows patients to undergo an extremely useful exam with minimal discomfort.