title: Bowel sounds analysis: a novel noninvasive method for diagnosis of small-volume ascites.
abstract: Ascites is more difficult to detect when only a small quantity is present. The aim of this pilot study was to determine the optimal bowel sound characteristics in order to distinguish no ascites from small-volume ascites by advanced processing of bowel sound wave patterns. This analysis results in the definition of the normal range of bowel sound patterns, thus providing a novel, simple, and noninvasive way of determining on abnormal pattern, which may reflect presence of small volume ascites. Cirrhotic patients with radiologically proven small-volume ascites and a control group were subjected to bowel sound recordings. The latter were analyzed using a denoising wavelet transform-based filter and a higher-order crossings-based technique in a blinded fashion for linearly distinguishing the two classes. Scatter plots of third-order zero crossings reflect distinct changes seen in the denoised bowel sound pattern between patients and controls due to altered transmission path, providing a distinct separation of all cirrhotic patients with small ascites from controls (P < 0.0001). We conclude that the proposed bowel sounds analysis appears to provide new information regarding the changes of the bowel sound patterns due to the presence of small-volume ascites, potentially contributing towards a safe, effective, noninvasive, and easily implemented alternative method for the diagnosis of small volume ascites at the bedside.
authors.affiliation: Liver Transplantation and Hepatobiliary Medicine, Royal Free Hospital, Hampstead, London NW3 2QG, UK.
authors.forename: Christos
authors.initials: C
authors.lastname: Liatsos
authors.forename: Leontios J
authors.initials: LJ
authors.lastname: Hadjileontiadis
authors.forename: Christos
authors.initials: C
authors.lastname: Mavrogiannis
authors.forename: David
authors.initials: D
authors.lastname: Patch
authors.forename: Stavros M
authors.initials: SM
authors.lastname: Panas
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Burroughs
mesh_terms: D000328:Adult; D016477:Artifacts; D001201:Ascites / Q000175:diagnosis*; D005260:Female; D005769:Gastrointestinal Motility / Q000502:physiology*; D006801:Humans; D008103:Liver Cirrhosis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009991:Oscillometry / Q000295:instrumentation*; D012016:Reference Values; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D013018:Sound Spectrography / Q000295:instrumentation*; D019023:Stethoscopes