title: Gastric and non-gastric signals in electrogastrography.
abstract: Electrogastrography (EGG) is the cutaneous recording of gastric myoelectrical activity, and the dominant frequency reflects the rhythm of the gastric slow wave. Ambulatory EGG is contaminated with a large amount of motion artifacts, and it is unclear how much of the signals comprising the dominant frequency originates from non-gastric sources. The aim of the present study was to evaluate the pattern of gastric and non-gastric signals in the dominant frequency histogram (DFH) obtained from long-term ambulatory EGG recordings. Ten normal controls and five post-gastrectomy patients participated in the present study. Twenty-four hour ambulatory EGG was recorded under normal daily conditions. The DFH of normal controls showed two distinctive peaks, and that of the post-gastrectomy patients, a single peak. The common peak at approximately 1.5 cpm was seen in both DFHs, and the peak at 3 cpm was seen only in the DFH of normal controls. Thus, the common peak was thought to be a product of non-gastric origin. In conclusion, the dominant frequency consists of gastric and non-gastric components which have a specific distribution pattern in the DFH. These findings quantified the contribution of gastric and non-gastric signals to the dominant frequencies in long-term ambulatory EGG.
authors.affiliation: Second Department of Surgery, Chiba University School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba, Japan. takehito.kaiho@nifty.ne.jp
authors.forename: T
authors.initials: T
authors.lastname: Kaiho
authors.forename: I
authors.initials: I
authors.lastname: Shimoyama
authors.forename: Y
authors.initials: Y
authors.lastname: Nakajima
authors.forename: T
authors.initials: T
authors.lastname: Ochiai
mesh_terms: D000328:Adult; D000368:Aged; D016477:Artifacts; D002940:Circadian Rhythm; D004594:Electrophysiology; D005260:Female; D005743:Gastrectomy; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D010507:Periodicity; D011184:Postoperative Period; D012016:Reference Values; D013270:Stomach / Q000502:physiology*; D013997:Time Factors