title: CT colonography: optimisation, diagnostic performance and patient acceptability of reduced-laxative regimens using barium-based faecal tagging.
abstract: To establish the optimum barium-based reduced-laxative tagging regimen prior to CT colonography (CTC). Ninety-five subjects underwent reduced-laxative (13 g senna/18 g magnesium citrate) CTC prior to same-day colonoscopy and were randomised to one of four tagging regimens using 20 ml 40%w/v barium sulphate: regimen A: four doses, B: three doses, C: three doses plus 220 ml 2.1% barium sulphate, or D: three doses plus 15 ml diatriazoate megluamine. Patient experience was assessed immediately after CTC and 1 week later. Two radiologists graded residual stool (1: none/scattered to 4: >50% circumference) and tagging efficacy for stool (1: untagged to 5: 100% tagged) and fluid (1: untagged, 2: layered, 3: tagged), noting the HU of tagged fluid. Preparation was good (76-94% segments graded 1), although best for regimen D (P = 0.02). Across all regimens, stool tagging quality was high (mean 3.7-4.5) and not significantly different among regimens. The HU of layered tagged fluid was higher for regimens C/D than A/B (P = 0.002). Detection of cancer (n = 2), polyps > or =6 mm (n = 21), and < or =5 mm (n = 72) was 100, 81 and 32% respectively, with only four false positives > or =6 mm. Reduced preparation was tolerated better than full endoscopic preparation by 61%. Reduced-laxative CTC with three doses of 20 ml 40% barium sulphate is as effective as more complex regimens, retaining adequate diagnostic accuracy.
authors.affiliation: Department of Specialist Radiology, University College Hospital, Euston Road, London, UK. csytaylor@yahoo.co.uk
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Taylor
authors.forename: Andrew
authors.initials: A
authors.lastname: Slater
authors.forename: David N
authors.initials: DN
authors.lastname: Burling
authors.forename: Emily
authors.initials: E
authors.lastname: Tam
authors.forename: Rebecca
authors.initials: R
authors.lastname: Greenhalgh
authors.forename: Louise
authors.initials: L
authors.lastname: Gartner
authors.forename: Julia
authors.initials: J
authors.lastname: Scarth
authors.forename: Robert
authors.initials: R
authors.lastname: Pearce
authors.forename: Paul
authors.initials: P
authors.lastname: Bassett
authors.forename: Steve
authors.initials: S
authors.lastname: Halligan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001466:Barium Sulfate; D002400:Cathartics / Q000008:administration & dosage*; D019343:Citric Acid / Q000008:administration & dosage; D023881:Colonography, Computed Tomographic / Q000592:standards*; D003287:Contrast Media; D003974:Diatrizoate Meglumine; D005243:Feces; D005260:Female; D006801:Humans; D054368:Laxatives / Q000008:administration & dosage*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage; D017060:Patient Satisfaction; D012676:Senna Extract / Q000008:administration & dosage; D011795:Surveys and Questionnaires
chemical_list: D002400:Cathartics; D003287:Contrast Media; D054368:Laxatives; D009942:Organometallic Compounds; D001466:Barium Sulfate; D019343:Citric Acid; D003974:Diatrizoate Meglumine; D012676:Senna Extract; C110422:magnesium citrate