Multichannel intraluminal impedance monitoring in the evaluation of patients with non-obstructive dysphagia

BACKGROUND: Non-obstructive dysphagia (NOD) often poses diagnostic problems. The aim of this study was to evaluate the value of the addition of multichannel intraluminal impedance (MII) recording to esophageal manometry in the work-up of patients with NOD. METHODS: A total of 40 consecutive patients with NOD underwent combined esophageal MII recording and perfusion manometry. Ten liquid and 10 viscous boluses were tested in each patient. Values for bolus presence time (BPT) at each of the four recording sites and total bolus transit time (TBTT) were calculated. Bolus transit (BT) was considered to be normal when BPT at all sites and TBTT were within the normal limits defined in 42 healthy subjects. Patients were judged to have normal transit if >= 80% of liquid and >= 70% of viscous swallows showed normal transit. RESULTS: The following manometric diagnoses were made: normal motility (20), ineffective esophageal motility (IEM) (13), diffuse esophageal spasm (DES) (4), and achalasia (3). Abnormal transit for liquid and/or viscous boluses was found in 35.3% of patients with normal motility, in 66.7% of DES patients, and in 100% of achalasia patients. In patients with achalasia quantification of BT was often made impossible by low initial impedance baseline. Two IEM patients (15.4%) showed normal liquid and viscous transit. Swallows showing normal transit had significantly longer duration of LES relaxation in patients with normal manometry and IEM (p < 0.05). CONCLUSIONS: MII recording identifies esophageal function abnormalities in NOD patients with normal manometry, IEM, and DES. The MII technique seems to be less suitable for the most severe end of the dysphagia spectrum like achalasia.