title: Performing an additional decubitus series at CT colonography.
abstract: OBJECTIVE
  To determine the rate and associated factors for acquiring a decubitus series at CT colonography (CTC), in addition to the standard supine and prone series.
  
  
  METHODS
  CTC examinations read centrally at one institution but performed at three different centers in 6,380 adults were reviewed to determine the frequency of an additional decubitus series. Results were analyzed according to study indication (primary screening vs. diagnostic for incomplete colonoscopy), practice site (academic vs. community), patient age, gender, body mass index (BMI), and temporal variation. At all sites, the CT technologist determined the need for an additional decubitus series, with infrequent radiologist input in select cases.
  
  
  RESULTS
  The frequency for the CT technologist to obtain a decubitus series at screening was 9.7% (578/5,952), compared with 22.9% (98/428) following failed colonoscopy (P < 0.001). The decubitus rate for screening at the academic center (9.4%, 550/5,871) was significantly lower than the community hospitals (34.6% combined, 28/81) (P < 0.001). The rate progressively increased with age, from 5.0% under age 50 to 28.0% over age 80. No significant difference was seen between men and women (10.3 vs. 9.2%), but a strong correlation existed with increased BMI, rising to >25% for BMI over 40. Marked temporal variation existed at the academic center, with quarterly rates ranging from 0 to 17%.
  
  
  CONCLUSIONS
  The frequency for performing a third series at CTC varies considerably according to indication, practice site, patient age, BMI, and time. These results have important implications for clinical practice, including the need for improved training and feedback for CT technologists.
authors.affiliation: Department of Radiology, University of Wisconsin School of Medicine and Public Health, Clinical Science Center, Madison, 53792-3252, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Buchach
authors.forename: David H
authors.initials: DH
authors.lastname: Kim
authors.forename: Perry J
authors.initials: PJ
authors.lastname: Pickhardt
mesh_terms: D001466:Barium Sulfate / Q000008:administration & dosage; D002400:Cathartics / Q000008:administration & dosage; D016009:Chi-Square Distribution; D019343:Citric Acid / Q000008:administration & dosage; D023881:Colonography, Computed Tomographic / Q000379:methods*; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D003287:Contrast Media / Q000008:administration & dosage; D003974:Diatrizoate Meglumine / Q000008:administration & dosage; D004573:Electrolytes / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage; D056888:Patient Positioning; D010710:Phosphates / Q000008:administration & dosage; D011092:Polyethylene Glycols / Q000008:administration & dosage; D012189:Retrospective Studies
chemical_list: D002400:Cathartics; D003287:Contrast Media; D004573:Electrolytes; C033608:Golytely; D009942:Organometallic Compounds; D010710:Phosphates; D001466:Barium Sulfate; D019343:Citric Acid; D011092:Polyethylene Glycols; D003974:Diatrizoate Meglumine; C110422:magnesium citrate; C018279:sodium phosphate