Polyp detection at 3-dimensional endoluminal computed tomography colonography: sensitivity of one-way fly-through at 120 degrees field-of-view angle.
OBJECTIVE
To investigate whether increasing the visual field-of-view (FOV) angle at 3-dimensional (3D) endoluminal computed tomography colonography (CTC) from 90 degrees to 120 degrees allows for single pass fly-through examination of the supine and prone views without sacrificing polyp detection.


METHODS
Primary 3D endoluminal CTC evaluation using a 120 degree FOV was performed by 2 experienced radiologists on 73 patients harboring 104 colonoscopy-proven polyps measuring 6 mm or larger. Unidirectional fly-through evaluation consisted of rectal-to-cecal (retrograde) navigation on the supine display and cecal-to-rectal (antegrade) navigation on the prone display. Electronic fluid subtraction was not used.


RESULTS
All 104 (100%) polyps were detectable with the single-pass 3D evaluation on either the retrograde supine or antegrade prone fly-through, with 86 (82.7%) of 104 polyps seen on both fly-through views. Of the 18 polyps detected on only one of the two 3D endoluminal passes (10 prone, 8 supine), 13 were either submerged under fluid (n = 12) or within a collapsed segment (n = 1); therefore, these were also undetectable on the corresponding 90 degrees bidirectional fly-through. The remaining 5 (4.8%) polyps were located behind a fold, but these polyps were all detectable on the other fly-through in the reverse direction.


CONCLUSIONS
Increasing the visual FOV angle to 120 degrees allows for a decrease in the total number of supine and prone 3D endoluminal fly-through passes from 4 to 2 without negatively impacting overall polyp detection.
Pickhardt
Perry J
PJ
Department of Radiology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53792-3252, USA. ppickhardt2@uwhealth.org
Schumacher
Clark
C
Kim
David H
DH
D000230:Adenocarcinoma / Q000000981:diagnostic imaging*; D018256:Adenomatous Polyps / Q000000981:diagnostic imaging*; D015331:Cohort Studies; D003106:Colon / Q000000981:diagnostic imaging; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging*; D003111:Colonic Polyps / Q000000981:diagnostic imaging*; D023881:Colonography, Computed Tomographic / Q000379:methods*; D003287:Contrast Media; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011187:Posture; D011856:Radiographic Image Enhancement / Q000379:methods*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
D003287:Contrast Media