title: Ultralow dose CT for pulmonary nodule detection with chest x-ray equivalent dose - a prospective intra-individual comparative study.
abstract: OBJECTIVE
  To prospectively evaluate the accuracy of ultralow radiation dose CT of the chest with tin filtration at 100 kV for pulmonary nodule detection.
  
  
  METHODS
  202 consecutive patients undergoing clinically indicated chest CT (standard dose, 1.8 ± 0.7 mSv) were prospectively included and additionally scanned with an ultralow dose protocol (0.13 ± 0.01 mSv). Standard dose CT was read in consensus by two board-certified radiologists to determine the presence of lung nodules and served as standard of reference (SOR). Two radiologists assessed the presence of lung nodules and their locations on ultralow dose CT. Sensitivity and specificity of the ultralow dose protocol was compared against the SOR, including subgroup analyses of different nodule sizes and types. A mixed effects logistic regression was used to test for independent predictors for sensitivity of pulmonary nodule detection.
  
  
  RESULTS
  425 nodules (mean diameter 3.7 ± 2.9 mm) were found on SOR. Overall sensitivity for nodule detection by ultralow dose CT was 91%. In multivariate analysis, nodule type, size and patients BMI were independent predictors for sensitivity (p < 0.001).
  
  
  CONCLUSIONS
  Ultralow dose chest CT at 100 kV with spectral shaping enables a high sensitivity for the detection of pulmonary nodules at exposure levels comparable to plain film chest X-ray.
  
  
  CONCLUSIONS
  • 91% of all lung nodules were detected with ultralow dose CT • Sensitivity for subsolid nodule detection is lower in ultralow dose CT (77.5%) • The mean effective radiation dose in 202 patients was 0.13 mSv • Ultralow dose CT seems to be feasible for lung cancer screening.
authors.affiliation: Department of Nuclear Medicine, University Hospital Zurich, University Zurich, Ramistrasse, Zurich, Switzerland. michael.messerli@usz.ch.|Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland. michael.messerli@usz.ch.
authors.forename: Michael
authors.initials: M
authors.lastname: Messerli
authors.affiliation: Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Kluckert
authors.affiliation: Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Meinhard
authors.initials: M
authors.lastname: Knitel
authors.affiliation: Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.|Department of Radiology, CHU Sainte-Justine, University of Montreal, Montréal, Québec, Canada.
authors.forename: Stephan
authors.initials: S
authors.lastname: Wälti
authors.affiliation: Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Lotus
authors.initials: L
authors.lastname: Desbiolles
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany.
authors.forename: Fabian
authors.initials: F
authors.lastname: Rengier
authors.affiliation: Department of Surgery, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: René
authors.initials: R
authors.lastname: Warschkow
authors.affiliation: Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Ralf W
authors.initials: RW
authors.lastname: Bauer
authors.affiliation: Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University Zurich, Zurich, Switzerland.
authors.forename: Hatem
authors.initials: H
authors.lastname: Alkadhi
authors.affiliation: Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.|Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University Zurich, Zurich, Switzerland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Leschka
authors.affiliation: Division of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.
authors.forename: Simon
authors.initials: S
authors.lastname: Wildermuth
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D055088:Early Detection of Cancer / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D055613:Multiple Pulmonary Nodules / Q000000981:diagnostic imaging; D011446:Prospective Studies; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D013902:Radiography, Thoracic / Q000379:methods; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
keywords: Computed Tomography; Image reconstruction; Lung cancer; Pulmonary Nodule; Radiation Dosage