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Abstract Background Articular screw penetration is one of the most common hardware-related problems after scaphoid fracture fixation, occurring in up to two-thirds of patients, in particular into the scaphotrapezotrapezoidal (STT) joint. The aim of this study was to investigate whether this clinically important issue could be detected using standard anteroposterior (AP) and lateral, as well as additional nonstandard fluoroscopic views using direct open visualization with magnifying loupes as reference standard. Materials and methods Ten fresh cadaver wrists were used for this imaging study. A 2.2 mm cannulated compression screws with a length of 24 mm was placed in the scaphoid and incrementally left to protrude at the STT joint up to 2 mm. Eight fluoroscopic views of the wrist were then obtained by rotating the forearm using goniometric measurements, keeping the image beam parallel to the floor: (1) anteroposterior with the wrist in neutral rotation, (2) anteroposterior with the wrist in ulnar deviation, (3) supinated oblique 60° from neutral (60° supinated oblique), (4) supinated oblique 45° from neutral (45° supinated oblique), (5) a true lateral, (6) a true lateral with the wrist in radial deviation, (7) pronated oblique 45° from neutral (45° pronated oblique), and (8) a pronated oblique 60° from neutral (60° pronated oblique). Results Standard anteroposterior and lateral fluoroscopy views (radiographically calibrated) of a percutaneous cannulated screw fixation of a scaphoid fracture were insufficient to detect distal articular penetration, missing half the amount of screw penetrations in the current study. The 45° pronated oblique view was found as the most sensitive in detecting STT penetration (p

Purpose: To compare tomosynthesis performance to radiography for the differentiation of sacroiliitis versus normal or degenerative changes in sacroiliac joints in patients with suspected axial spondyloarthritis (SpA). Materials and methods: Radiography, tomosynthesis and CT of sacroiliac joints (29 patients) were performed on the same day in consecutive patients with suspected SpA. The examinations were retrospectively read independently, blinded by two radiologists (one junior and one senior, and twice by one junior). Interobserver and intraobserver agreement was evaluated using the kappa coefficient. Effective doses for each imaging sensitivity, specificity and accuracy were assessed and compared with CT as gold standard. Results: CT detected 15/58 joints with sacroiliitis. The imaging sensitivity, specificity and accuracy were 60%, 84% and 44%, respectively, for radiography and 87%, 91% and 77% for tomosynthesis. The mean effective dose for tomosynthesis was significantly lower than that of CT (5-fold less) and significantly higher than that of radiography (8-fold more). Conclusion: Tomosynthesis is superior to radiography for sacroiliitis detection in patients with suspected SpA, with 5-fold less radiation exposure than CT.

Images from 64 patients undergoing an enhanced abdominal-pelvis scan at portal phase in dual-energy CT mode for the diagnosis of colitis or bowel obstruction were retrospectively analyzed. Acquisitions were performed on a third-generation dual-source CT (DSCT) 100/Sn150 kVp. Mixed images were generated, as well as virtual monoenergetic images (VMIs) at 40/50/60/70 keV. Objective image quality was assessed on VMIs and mixed images by measuring contrast, noise and contrast-to-noise ratio (CNR). Noise, smoothing and overall image quality were subjectively analyzed by two radiologists using Likert scales. For both patient groups, the noise decreased significantly according to the energy level from 40 to 60 keV by −47.2 ± 24.0% for bowel obstruction and −50.4 ± 18.2% for colitis. It was similar between 60 and 70 keV (p = 0.475 and 0.059, respectively). Noise values were significantly higher in VMIs than in mixed images, except for 70 keV (p = 0.53 and 0.071, respectively). Similar results were observed for contrast values, with a decrease between 40 and 70 keV of −56.3 ± 7.9% for bowel obstruction −56.2 ± 10.9% for colitis. The maximum CNR value was found at 60 keV compared to other energy levels and mixed images, but there was no significant difference with the other energy levels apart from 70 keV (−9.7 ± 9.8%) for bowel obstruction and 40 keV (−6.6 ± 8.2%) and 70 keV (−5.8 ± 9.2%) for colitis. The VMIs at 60 keV presented higher scores for all criteria for bowel obstruction and colitis, with no significant difference in smoothing score compared to mixed images (p = 0.119 and p = 0.888, respectively).