title: Monitoring the lower oesophageal sphincter: sphinctometer or sleeve?
abstract: Two methods have been used to study lower oesophageal sphincter (LOS) function in gastro-oesophageal reflux disease: the sleeve sensor and the sphinctometer. Our aim was to directly compare the sleeve and sphinctometer in vivo. Ten asymptomatic volunteers were intubated with a perfused assembly incorporating a sleeve sensor, a solid-state assembly incorporating a sphinctometer and a pH probe. LOS function was recorded pre- and post-prandially. During basal periods sleeve and sphinctometer readings correlated well both within and between subjects (r2 = 0.89 (P < 0.0001)). However, the sphinctometer relaxed less during swallows (median 42 (interquartile range 27-55)% vs 73 (62-81)% (P < 0.001)), transient LOS relaxations (TLOSR) (50 (40-70)% vs 94 (88-100)% (P < 0.001)) and reflux episodes (67 (59-75)% vs 97 (91-100)% (P = 0.02)). Using criteria derived from 10 dry swallows, the expected relaxation of the sphinctometer during TLOSR was defined. The sphinctometer had an overall sensitivity ranging from 43 to 71% for the detection of TLOSR with 11-22 false positive relaxations, depending on the criteria employed. Sensitivity was particularly poor in those with low basal LOS pressure. The sphinctometer has a lower capacity to register LOS relaxations than the sleeve sensor, which limits its value in studying the pathophysiology of reflux disease.
authors.affiliation: Department of Gastroenterology, Northern General Hospital, Sheffield, UK.
authors.forename: N J
authors.initials: NJ
authors.lastname: Trudgill
authors.forename: S A
authors.initials: SA
authors.lastname: Riley
mesh_terms: D000328:Adult; D004943:Esophagogastric Junction / Q000502:physiology*; D006801:Humans; D016014:Linear Models; D008365:Manometry; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D012680:Sensitivity and Specificity