title: Multidetector CT detection of peritoneal metastases: evaluation of sensitivity between standard 2.5 mm axial imaging and maximum-intensity-projection (MIP) reconstructions.
abstract: OBJECTIVE
  Our purpose was to evaluate the sensitivity of multidetector CT for the detection of peritoneal metastases between standard 2.5 mm axial imaging and maximum-intensity-projection (MIP) reconstructions.
  
  
  METHODS
  The Institutional Review Board approved this retrospective study and waived the need to obtain patient consent. We retrospectively identified 36 patients with pancreatic adenocarcinoma and peritoneal metastatic disease who underwent a pancreatic protocol CT examination of the abdomen and pelvis between January 2012 and January 2014. Three independent radiologists reviewed a randomized combination of standard axial (2.5 mm reconstructed thickness, 2.5 mm interval) and axial MIP reconstructions (6, 3 mm interval) over two sessions. Each reader recorded metastasis location in PACS. Subsequent consensus review by two radiologists determined the final number and size of metastases.
  
  
  RESULTS
  The reviewers found 328 peritoneal implants in 36 patients. After accounting for the size, location, and number of lesions as well as multiple readers, a generalized estimating equations model showed that the statistical combination of MIP with standard technique significantly increased the odds of correctly identifying a lesion (OR 2.16; 95% CI 1.86-2.51; p value < 0.0001) compared to standard technique alone. MIP reconstruction as a standalone technique was less sensitive compared to standard technique alone (OR 0.81; 95% CI 0.65-0.99; p value = 0.0468). When compared to standard axial imaging, evaluation via MIP reconstructions resulted in the identification of an additional 50 (15%), 45 (14%), and 55 (17%) lesions by Readers 1-3, respectively.
  
  
  CONCLUSIONS
  The axial 6 mm MIP series is complimentary in the CT evaluation of peritoneal metastases. MIP reconstruction evaluation identified a significant number of additional lesions, but is not adequate as a standalone technique for peritoneal cavity assessment.
authors: Department of Diagnostic Radiology, The University of Texas M. D. Anderson Cancer Center, Pickens Academic Tower, 1400 Pressler Street, Unit 1473, Houston, TX, 77030-4009, USA. cjensen@mdanderson.org.
authors: Corey T
authors: CT
authors: Jensen
authors: Department of Diagnostic Radiology, The University of Texas M. D. Anderson Cancer Center, Pickens Academic Tower, 1400 Pressler Street, Unit 1473, Houston, TX, 77030-4009, USA.
authors: Rafael A
authors: RA
authors: Vicens-Rodriguez
authors: Department of Diagnostic Radiology, The University of Texas M. D. Anderson Cancer Center, Pickens Academic Tower, 1400 Pressler Street, Unit 1473, Houston, TX, 77030-4009, USA.
authors: Nicolaus A
authors: NA
authors: Wagner-Bartak
authors: Department of Biostatistics, The University of Texas M. D. Anderson Cancer Center, Houston, TX, USA.
authors: Patricia S
authors: PS
authors: Fox
authors: Department of Diagnostic Radiology, The University of Texas M. D. Anderson Cancer Center, Pickens Academic Tower, 1400 Pressler Street, Unit 1473, Houston, TX, 77030-4009, USA.
authors: Silvana C
authors: SC
authors: Faria
authors: University Hospital Joan XXIII (Tarragona), Avda. Jaume Balmes, XX, X-X, Vilanova i la Geltru Barcelona, 08800, Spain.
authors: Ivan
authors: I
authors: Carrion
authors: Department of Diagnostic Radiology, The University of Texas M. D. Anderson Cancer Center, Pickens Academic Tower, 1400 Pressler Street, Unit 1473, Houston, TX, 77030-4009, USA.
authors: Aliya
authors: A
authors: Qayyum
authors: Department of Diagnostic Radiology, The University of Texas M. D. Anderson Cancer Center, Pickens Academic Tower, 1400 Pressler Street, Unit 1473, Houston, TX, 77030-4009, USA.
authors: Eric P
authors: EP
authors: Tamm
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D016609:Neoplasms, Second Primary / Q000000981:diagnostic imaging*; D015588:Observer Variation; D010190:Pancreatic Neoplasms / Q000473:pathology*; D010534:Peritoneal Neoplasms / Q000000981:diagnostic imaging* / Q000556:secondary*; D010537:Peritoneum / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
keywords: CT; MIP; Maximum intensity projection; Peritoneal evaluation; Peritoneal metastases