A new technique for measuring lower oesophageal sphincter competence in patients.

Oesophageal sphincter measurements were carried out on 80 patients using the stationary pull through technique; Normals (n = 21), Nutcracker (n = 12), Refluxers (n = 21), and Barrett's (n = 26). Sphincter pressure (LOSP), abdominal length of sphincter, and overall sphincter length were measured. The Sphincter Function Index (SFI) was calculated as the product of sphincter pressure and percentage sphincter length (AL) exposed to abdominal pressure. Patients also had routine endoscopy and 24 hour pHmetry. SFI values discriminated between all four groups. LOSP was significantly different for Barrett's (p < 0.01) and Nutcracker (p < 0.01) compared to normals. AL was significant for Refluxers (p < 0.001) and Barrett's (p < 0.001) compared to normals. SFI gives better discrimination than LOSP or AL alone and may be useful in evaluating the response to treatment.