The esophagus is a hollow muscular tube that consists of 3 functional regions: the UES, the tubular portion of the esophagus, and the LES. Its primary function is to transport liquids or food to the stomach and to prevent retrograde movement of gastric contents.
Manometry allows the depiction of pressure profiles generated by esophageal peristalsis and provides clinically relevant information on esophageal motor function. Conventional manometry involves the use of catheters with a few widely spaced channels that are continuously perfused with water. Differences in the resistance to water flow among the manometric channels are measured by pressure sensors and then converted to an electrical signal, and recordings are interpreted as line tracings. Because of the small number of channels and the wide gaps between those channels, a time-consuming pull-through technique is needed. Use of an increased number of pressure sensors on the catheter and creation of spatiotemporal contour plots for data display have provided a new technique: HRM. This technique was first described in 1998.1 Since then, HRM has become the criterion-referenced standard for the evaluation of esophageal function in humans. Most importantly the dynamic interaction of the UES, tubular portion of the esophagus, and LES during swallowing can be evaluated concurrently, which facilitates detection of disorders in this complex functional system.
Furthermore, because of the closely spaced pressure sensors, there is no loss of information, even for subtle functional abnormalities limited to a short segment of the esophagus.2 Moreover, displacements of the high pressure zone (esophagogastric junction, including the LES) from the recording channel during breathing-related movements as well as a decrease in esophageal length during swallowing cannot be misinterpreted as LES relaxation (so-called pseudorelaxation).3 Also, pattern recognition of the colored contour plot facilitates diagnosis,4 and the soft catheter material improves patient comfort during the procedure.
In veterinary medicine, conventional manometry has rarely been used in companion animals and has not gained wide acceptance as a diagnostic tool.5,6 In clinical practice, fluoroscopic evaluations of swallowing are most commonly used for the assessment of esophageal disorders and to provide information on effectiveness of bolus transport and esophageal clearance. Neither fluoroscopy nor HRM allows determination of the underlying cause of dysfunction, but HRM provides the possibility of pressure measurements, which therefore can be used to directly assess esophageal function.7,8 To the authors' knowledge, HRM has not been performed in dogs.
The primary objective of the study reported here was to evaluate HRM as a diagnostic tool for esophageal functional disorders in dogs. Second, because intranasal insertion of a catheter was expected to be problematic in uncooperative patients, we also intended to assess potential effects of sedation on manometric data.
Bolus transit time
Contractile front velocity
Lower esophageal sphincter
Peristaltic contractile integral
Upper esophageal sphincter
ManoScan ESO catheter, small diameter regular (EAS), Sierra Scientific Instruments, Los Angeles, Calif.
Sensitivity Control, Royal Canin, Dällikon, Switzerland.
Smart Mouse, ManoView ESO analysis software, Sierra Scientific Instruments, Los Angeles, Calif.
GraphPad Prism, version 5.0, GraphPad Software Inc, San Diego, Calif.
Sweis R, Anggiansah A, Wong T, et al. T1889 inclusion of solid swallows and a test meal increase the clinical utility of high resolution manometry in patients with dysphagia (abstr). Gastroenterology 2010;138:S600.
1. Clouse RE, Staiano A & Alrakawi A. Development of a topographic analysis system for manometric studies in the gastrointestinal tract. Gastrointest Endosc 1998; 48: 395–401.
2. Fox M, Hebbard G & Janiak P, et al. High-resolution manometry predicts the success of oesophageal bolus transport and identifies clinically important abnormalities not detected by conventional manometry. Neurogastroenterol Motil 2004; 16: 533–542.
3. Clouse RE, Staiano A & Alrakawi A, et al. Application of topographical methods to clinical esophageal manometry. Am J Gastroenterol 2000; 95: 2720–2730.
4. Soudagar AS, Sayuk GS, Gyawali CP. Learners favour high resolution oesophageal manometry with better diagnostic accuracy over conventional line tracings. Gut 2012; 61: 798–803.
5. Diamant N, Szczepanski M & Mui H. Idiopathic megaesophagus in the dog: reasons for spontaneous improvement and a possible method of medical therapy. Can Vet J 1974; 15: 66–71.
6. Rogers WA, Fenner WR, Sherding RG. Electromyographic and esophagomanometric findings in clinically normal dogs and in dogs with idiopathic megaesophagus. J Am Vet Med Assoc 1979; 174: 181–183.
7. Pouderoux P, Shi G & Tatum RP, et al. Esophageal solid bolus transit: studies using concurrent videofluoroscopy and manometry. Am J Gastroenterol 1999; 94: 1457–1463.
8. Davies HA, Evans KT & Butler F, et al. Diagnostic value of “bread-barium” swallow in patients with esophageal symptoms. Dig Dis Sci 1983; 28: 1094–1100.
9. Ghosh SK, Pandolfino JE & Zhang Q, et al. Quantifying esophageal peristalsis with high-resolution manometry: a study of 75 asymptomatic volunteers. Am J Physiol Gastrointest Liver Physiol 2006; 290:G988–G997.
10. Pandolfino JE, Gosh SK & Rice J, et al. Classifying esophageal motility by pressure topography characteristics: a study of 400 patients and 75 controls. Am J Gastroenterol 2008; 103: 27–37.
11. Strombeck DR & Harrold D. Effect of gastrin, histamine, serotonin, and adrenergic amines on gastroesophageal sphincter pressure in the dog. Am J Vet Res 1985; 46: 1684–1690.
12. Sweis R, Anggiansah A & Wong T, et al. Normative values and inter-observer agreement for liquid and solid bolus swallows in upright and supine positions as assessed by esophageal high-resolution manometry. Neurogastroenterol Motil 2011; 23: 509–517.
13. Roman S, Damon H & Pellissier PE, et al. Does body position modify the results of oesophageal high resolution manometry? Neurogastroenterol Motil 2010; 22: 271–275.
14. Xiao Y, Read A & Nicodème F, et al. The effect of a sitting vs supine posture on normative esophageal pressure topography metrics and Chicago classification diagnosis of esophageal motility disorders. Neurogastroenterol Motil 2012; 24:e509–e516.
15. Xiao Y, Nicodème F & Kahrilas PJ, et al. Optimizing the swallow protocol of clinical high-resolution esophageal manometry studies. Neurogastroenterol Motil 2012; 24:e489–e496.
16. Cook IJ, Dent J & Shannon S, et al. Measurement of upper esophageal sphincter pressure—effect of acute emotional stress. Gastroenterology 1987; 93: 526–532.
17. Mittal RK, Stewart WR & Ramahi M, et al. The effects of psychological stress on the esophagogastric junction pressure and swallow-induced relaxation. Gastroenterology 1994; 106: 1477–1484.
18. Srinivasan R, Vela MF & Katz PO, et al. Esophageal function testing using multichannel intraluminal impedance. Am J Physiol Gastrointest Liver Physiol 2011; 280:G457–G462.
19. Pal A, Williams RB & Cook IJ, et al. Intrabolus pressure gradient identifies pathological constriction in the upper esophageal sphincter during flow. Am J Physiol Gastrointest Liver Physiol 2003; 285:G1037–G1048.
20. Scherer JR, Kwiatek MA & Soper NJ, et al. Functional esophagogastric junction obstruction with intact peristalsis: a heterogeneous syndrome sometimes akin to achalasia. J Gastrointest Surg 2009; 13: 2219–2225.
21. Ghosh SK, Pandolfino JE & Zhang Q, et al. Deglutitive upper esophageal sphincter relaxation: a study of 75 volunteer subjects using solid-state high-resolution manometry. Am J Physiol Gastrointest Liver Physiol 2006; 291: 525–531.
22. Bredenoord AJ & Smout J. Esophageal motility testing: impedance-based transit measurement and high-resolution manometry. Gastroenterol Clin North Am 2008; 37: 775–791.
23. Gibbon KJ, Trepanier LA, Delaney FA. Phenobarbital-responsive ptyalism, dysphagia, and apparent esophageal spasm in a German Shepherd puppy. J Am Anim Hosp Assoc 2004; 40: 230–237.