title: Three-Dimensional Anorectal Manometry Enhances Diagnostic Gain by Detecting Sphincter Defects and Puborectalis Pressure.
abstract: Constipation and fecal incontinence (FI) are common and are often evaluated with anorectal manometry. Three-dimensional high-resolution anorectal manometry (HRAM) is a promising technology; however, implementation has been limited by lack of metrics and unclear clinical utility.
  
  
  
  To investigate the diagnostic utility of 3D HRAM compared to 2D HRAM.
  
  
  
  Three-dimensional HRAM studies performed from April 2012 to October 2013 were identified and re-interpreted by two blinded investigators examining 3D function. Disagreements were resolved by a third investigator. Puborectalis (PR) visualization, focal defects, and dyssynergy were reported. Differences between groups were analyzed with Fisher's exact test. Discordance was analyzed with McNemar Chi-square test.
  
  
  
  Two hundred and twenty-one 3D HRAM studies were identified. Mean age and BMI were 52.2 ± 17.4 and 27.1 ± 7.5 years (81% female, 74% white). Most common indications for 3D HRAM were constipation (65%) and FI (28%). PR function was visualized in 81% (rest), 97% (squeeze), and 73% (strain). PR was visualized less often at rest in FI than constipation (68 vs. 85%, p = 0.007). Defects were identified twice as often in FI than constipation (19 vs. 10%, p = 0.113). Twenty-nine defects (86% anterior) were visualized on 3D HRAM. Inter-reader agreement was moderate for PR function (κ = 0.471), but fair for focal defects (κ = 0.304).
  
  
  
  PR function and focal defects can be visualized on 3D-HRAM with added diagnostic benefit compared to 2D. Fair inter-reader agreement for focal defects highlights the need for quantitative metrics.
authors.affiliation: Division of Gastroenterology and Hepatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Shreya
authors.initials: S
authors.lastname: Raja
authors.affiliation: Division of Gastroenterology and Hepatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Francis C
authors.initials: FC
authors.lastname: Okeke
authors.affiliation: Division of Gastroenterology and Hepatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Ellen M
authors.initials: EM
authors.lastname: Stein
authors.affiliation: Division of Gastroenterology and Hepatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Sameer
authors.initials: S
authors.lastname: Dhalla
authors.affiliation: Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA, USA.
authors.forename: Monica
authors.initials: M
authors.lastname: Nandwani
authors.affiliation: Division of Gastroenterology and Hepatology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Kristle L
authors.initials: KL
authors.lastname: Lynch
authors.affiliation: Division of Gastroenterology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: C Prakash
authors.initials: CP
authors.lastname: Gyawali
authors.affiliation: Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA, USA. john.clarke@stanford.edu.
authors.forename: John O
authors.initials: JO
authors.lastname: Clarke
mesh_terms: D000328:Adult; D000368:Aged; D001003:Anal Canal / Q000000981:diagnostic imaging*; D003248:Constipation / Q000000981:diagnostic imaging*; D005242:Fecal Incontinence / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008365:Manometry / Q000379:methods*; D008875:Middle Aged; D012007:Rectum / Q000000981:diagnostic imaging*; D012189:Retrospective Studies
keywords: Anorectal manometry; Constipation; Dyssynergy; Fecal incontinence