1. Clarification of the esophageal function defect in patients with manometric ineffective esophageal motility: studies using combined impedance-manometry 
Radu Tutuian, Donald O Castell 
Clinical Gastroenterology and Hepatology 
Volume 2, Issue 3, Pages (March 2004)
DOI: /S (04)

2. Figure 1
Nine-channel combined multichannel intraluminal impedance (MII) and manometry (EM) catheter. Circumferential solid-state pressure sensors located in the lower esophageal sphincter (LES) high-pressure zone (P5) and 5 cm above it (P4); unidirectional solid-state pressure sensors located 10 (P3), 15 (P2), and 20 cm (P1) above the LES. Impedance-measuring segments centered 5 (Z4), 10 (Z3), 15 (Z2), and 20 cm (Z1) above the LES.
Clinical Gastroenterology and Hepatology 2004 2, DOI: ( /S (04) )

3. Figure 2
Impedance changes observed during bolus transit over a single pair of measurement rings separated by 2 cm. A rapid increase in resistance is noted when air traveling in front of the bolus head reaches the impedance-measuring segment, followed by a decrease in impedance after higher conductive bolus material passes the measuring site. Bolus entry is considered at the 50% decrease in impedance from baseline relative to nadir and bolus exit at the 50% recovery point from nadir to baseline. Lumen narrowing produced by the contraction transiently increases the impedance above baseline.
Clinical Gastroenterology and Hepatology 2004 2, DOI: ( /S (04) )

4. Figure 3
Percentage of swallows with complete bolus transit based on the number of distal esophageal pressure sites (i.e., 5 and 10 cm above the LES) recording a contraction amplitude <30 mm Hg.
Clinical Gastroenterology and Hepatology 2004 2, DOI: ( /S (04) )

5. Figure 4
(A) Receiver operating characteristic (ROC) curves for liquid swallows plot sensitivity against 1-specificity of distal esophageal amplitudes (DEAs) to identify swallows with complete bolus transit. (B) ROC curves for viscous swallows plot sensitivity against 1-specificity of DEAs to identify swallows with complete bolus transit. (A, B) Values in parentheses after the cutoff value are sensitivity and specificity (respectively) to identify complete bolus transit.
Clinical Gastroenterology and Hepatology 2004 2, DOI: ( /S (04) )

6. Figure 5
Distribution of patients based on number of manometrically ineffective liquid and viscous swallows. Bars indicate number of patients with normal and abnormal bolus transit. A greater proportion of patients with <5 low-amplitude contractions had normal bolus transit compared with those with ≥5 low-amplitude contractions for both liquid and viscous swallows (P < 0.05).
Clinical Gastroenterology and Hepatology 2004 2, DOI: ( /S (04) )