Evaluation for intestinal motility disorders aided by refined diagnostic tests
Motility or functional gastrointestinal (GI) disorders can be the underlying cause in approximately one-third or more of patients who present with GI symptoms. Although conventional wisdom holds that these disorders lack a well-defined pathophysiology or specific therapy, Mayo Clinic gastroenterologists note that a careful clinical assessment integrated with the results of refined diagnostic tests is extremely useful for effectively managing these patients.
Many of the tests used to evaluate bowel disorders discussed below were pioneered or validated through extensive research at Mayo Clinic, and many are only available at Mayo.
A noninvasive, radionuclide imaging test with broad clinical indications, scintigraphy measures gastric emptying and small bowel and colonic transit. At Mayo Clinic, a unique version of this test provides a screening assessment of gastrointestinal motor function within 24 to 48 hours. The results of the test provide the basis for sophisticated and more-refined intraluminal assessments of gastric and small intestinal or colonic motility.
For example, gastroduodenal manometry is used to diagnose gastric dysmotility or intestinal pseudo-obstruction, while colonic barostat testing may disclose severe colonic motor dysfunction that may be amenable to surgery. On the other hand, a majority of patients referred to Mayo Clinic with a diagnosis of gastroparesis are found to have normal stomach emptying when transit scintigraphy is performed properly.
Single-photon emission computerized tomography (SPECT)
This radionuclide test uses 3-D images to calculate stomach volume before and after a sample meal and is the only noninvasive approach to quantify gastric accommodation. Impaired gastric accommodation may explain upper GI symptoms such as early satiety and is potentially amenable to specific drug therapy.
High-resolution anorectal manometry
High-resolution anorectal manometry (HRM) is increasingly used to assess anorectal function in clinical practice. Until recently, however, normal values had not been established, limiting identification of abnormal values. Mayo Clinic gastroenterologists recently found that contrary to common belief, a majority of young, healthy women have a negative anorectal gradient, which limits the utility of a negative gradient with HRM to diagnose defecation disorders.
Mayo Clinic investigators have used HRM and magnetic resonance defecography to identify phenotypes in constipation and fecal incontinence. These results can be very useful in directing therapy, such as pelvic floor rehabilitation in patients with a defecation disorder.
Pelvic floor magnetic resonance imaging (MRI)
MRI provides detailed images of the pelvic floor that help diagnose defecation disorders and organ-specific prolapse without exposure to ionizing radiation. Mayo Clinic is one of only a few centers offering specialized pelvic floor retraining for patients with refractory constipation due to pelvic floor dysfunction.
Motility Interest Group
In 2012, Mayo Clinic's Motility Interest Group saw nearly 1,700 new and established patients. This group offers a multidisciplinary approach, with many specialists working together seamlessly. Patients seen by Motility Interest Group staff benefit from:
- Access to refined diagnostic tests
- An informed approach to the latest pharmacotherapy
- The use of psychological therapies
- Skilled pelvic floor therapists
- Experienced laparoscopic surgeons
- The staff's willingness and ability to deal with especially challenging problems