Background: Combined multichannel intraluminal impedance and esophageal manometry (MII-EM) is a technique that uses an FDA-approved device allowing simultaneous evaluation of bolus transit (MII) in relation to pressure changes (EM).
Methods: During a 9-month period, beginning from July 2002 through March 2003, we prospectively performed combined MII-EM on all patients referred for esophageal function testing. Each patient received 10 liquid and 10 viscous swallows. Manometric findings were reported based on criteria described by Spechler and Castell for liquid swallows. MII findings were reported as having normal bolus transit if >/=80% (8/10) of liquid and >/=70% (7/10) of viscous swallows had complete bolus transit.
Results: Three-hundred fifty studies were evaluated from patients with a variety of symptoms having the following manometric diagnoses: normal manometry (125), achalasia (24), scleroderma (4), ineffective esophageal motility (IEM) (71), distal esophageal spasm (DES) (33), nutcracker esophagus (30), hypertensive lower esophageal sphincter (LES) (25), hypotensive LES (5), and poorly relaxing LES (33). None of the patients with achalasia and scleroderma had normal bolus transit. Fifty-one percent of patients with IEM and 55% of patients with DES had normal bolus transit while almost all (more than 95%) patients with normal esophageal manometry, nutcracker esophagus, poorly relaxing LES, hypertensive LES, and hypotensive LES had normal bolus transit. Dysphagia occurred most often in patients with incomplete bolus transit on MII testing.
Conclusion: Esophageal body pressures primarily determine bolus transit with isolated LES abnormalities appearing to have little effect on esophageal function. MII clarifies functional abnormalities in patients with abnormal manometric studies.