title: The small-caliber esophagus: radiographic sign of idiopathic eosinophilic esophagitis.
abstract: OBJECTIVE
  To evaluate a small-caliber esophagus at barium esophagography with idiopathic eosinophilic esophagitis (IEE) and determine if there is a useful threshold diameter for suggesting this diagnosis.
  
  
  METHODS
  The institutional review board approved this retrospective study and waived informed consent. This study was HIPAA compliant. A search of the radiology database (by using the search term small-caliber esophagus) revealed 10 patients with a small-caliber esophagus at barium esophagography who had IEE (defined as more than 20 eosinophils per high-power field in endoscopic biopsy specimens). Images were reviewed to characterize findings and determine the length of narrowing. Luminal diameters were measured at three levels for nine patients and nine control subjects, and mean diameter, range, and standard deviation were determined at each level. An analysis of variance test was performed to determine whether the difference between the range of mean thoracic esophageal diameters in patients with IEE versus that in control subjects was significant.
  
  
  RESULTS
  All 10 patients had long-segment but variable-length narrowing of the thoracic esophagus (mean length, 15.4 cm) with tapered margins. The mean diameter at the aortic arch, carina, and one vertebral body above the gastroesophageal junction was 13.9, 14.3, and 15.1 mm, respectively, for patients with small-caliber esophagus versus 20.2, 30.3, and 28.7 mm for control subjects. The mean overall diameter was 14.7 mm for patients with small-caliber esophagus versus 26.3 mm for control subjects. In the nine patients in whom the luminal diameter was measured, the mean thoracic esophageal diameter was 20 mm or less; all nine control subjects had a mean thoracic esophageal diameter greater than 20 mm. The difference in the range of mean thoracic esophageal diameters between these two groups was highly significant (P < .0001), so 20 mm was a useful threshold diameter for suggesting this diagnosis.
  
  
  CONCLUSIONS
  The small-caliber esophagus of IEE is characterized at barium esophagography by long-segment but variable-length narrowing of the thoracic esophagus, with a mean length of 15.4 cm, a diameter of 20 mm or less, smooth contours, and tapered margins.
authors.affiliation: Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Sarah B
authors.initials: SB
authors.lastname: White
authors.forename: Marc S
authors.initials: MS
authors.lastname: Levine
authors.forename: Stephen E
authors.initials: SE
authors.lastname: Rubesin
authors.forename: Geoffrey S
authors.initials: GS
authors.lastname: Spencer
authors.forename: David A
authors.initials: DA
authors.lastname: Katzka
authors.forename: Igor
authors.initials: I
authors.lastname: Laufer
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001466:Barium Sulfate; D003287:Contrast Media; D004802:Eosinophilia / Q000000981:diagnostic imaging* / Q000209:etiology; D004940:Esophageal Stenosis / Q000150:complications / Q000000981:diagnostic imaging*; D004941:Esophagitis / Q000000981:diagnostic imaging* / Q000209:etiology; D004945:Esophagoscopy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies
chemical_list: D003287:Contrast Media; D001466:Barium Sulfate