title: Commissioning of a new SeHCAT detector and comparison with an uncollimated gamma camera.
abstract: Measurements of SeHCAT (tauroselcholic [75selenium] acid) retention have been used to diagnose bile acid malabsorption for a number of years. In current UK practice the vast majority of centres calculate uptake using an uncollimated gamma camera. Because of ever-increasing demands on gamma camera time, a new 'probe' detector was designed, assembled and commissioned. To validate the system, nine patients were scanned at day 0 and day 7 with both the new probe detector and an uncollimated gamma camera. Commissioning results were largely in line with expectations. Spatial resolution (full-width 95% of maximum) at 1 m was 36.6 cm, the background count rate was 24.7 cps and sensitivity at 1 m was 720.8 cps/MBq. The patient comparison study showed a mean absolute difference in retention measurements of 0.8% between the probe and uncollimated gamma camera, and SD of ± 1.8%. The study demonstrated that it is possible to create a simple, reproducible SeHCAT measurement system using a commercially available scintillation detector. Retention results from the probe closely agreed with those from the uncollimated gamma camera.
authors.affiliation: Nuclear Medicine Department, Sheffield Teaching Hospital NHS Foundation Trust, Sheffield, UK.
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Taylor
authors.forename: Philip G
authors.initials: PG
authors.lastname: Hillel
authors.forename: John M
authors.initials: JM
authors.lastname: Himsworth
mesh_terms: D001646:Bile / Q000000981:diagnostic imaging; D004867:Equipment Design; D005260:Female; D015902:Gamma Cameras / Q000592:standards*; D006801:Humans; D008297:Male; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D013656:Taurocholic Acid / Q000031:analogs & derivatives*; D013667:Technetium
chemical_list: D019275:Radiopharmaceuticals; D013656:Taurocholic Acid; D013667:Technetium; C033638:23-seleno-25-homotaurocholic acid