Optima ct670

Pelvic MDCT images from five different CT scanners [AquilionONE (Canon Medical Systems, Otawara, Japan), Discovery CT750 HD (GE Medical Systems, Waukesha, WI, USA), Optima CT670 (GE Medical Systems, Milwaukee WI, USA), iCT 256 (Philips Medical System, Best, Netherlands), SOMATOM Definition Flash (Siemens Medical Systems, Forchheim, Germany)] were obtained with the following parameters: 100–300 mA, 120 kV, pitch of 0.599–0.984, thickness of 1–1.2 mm, and rotation time of 0.42–0.6 s. Iohexol (300 mg iodine/mL) with 85–100 mL volume was administered into the vein using a power injector at the speed of 2.0–3.0 mL/s. Then, the post-contrast CT scans from the arterial phase (AP, 30 s), venous phase (VP, 60 s), and equilibrium phase (EP, 90–120 s) were attained.

GE (Optima CT670) 64 slice spiral CT is adopted: tube voltage 120 kV, tube current 39 mAs, pitch 0.8 and layer thickness 5 mm; Philips (Brilliance) 16 slice spiral CT scanning: tube voltage 120 kV, tube current automatic adjustment, pitch 1, layer thickness 5 mm; the scanning range was from the upper edge of the sternoclavicular joint to the bottom of the lung and breath-holding scanning at the end of inhalation. The images of lung window reconstruction, mediastinum reconstruction, and bone window reconstruction were evaluated.

CT examinations were performed on a multidetector row scanner (SOMATOM Definition Flash, Siemens Medical Systems; iCT 256, Philips Healthcare; or Optima CT670, GE Healthcare). All patients were requested to fast for at least six hours before the procedure. All patients underwent abdominal CT protocol or CT enterography. For abdominal CT protocol, patients received 600–1000 mL water orally prior to the examination. For CT enterography, patients were encouraged to drink 1000–2000 mL 20% mannitol for over 40–60 min prior to the CT scanning.
All patients were in the supine position, and the scan covered the entire abdomen. The patients were trained to hold their breath during CT scanning. Intravenous 1.0 mL/kg contrast medium (iohexol injection, 300 mg/mL, Beilu Pharmaceutical Co. Ltd., Beijing, China) was injected at a flow rate of 3.0–3.5 mL/s using a power injector (Ulrich CT Plus 150, Ulrich Medical), followed by a saline flush (20 mL). Arterial phase scanning and venous phase scanning were performed at 30 seconds and 70 seconds, respectively, after initiation of contrast material injection.
The CT scanning parameters were as follows: automatic tube current and tube voltage 120 kV, detector collimation 64 × 0.6 or 128 × 0.625 mm, matrix 512 × 512, slice thickness 5 mm, slice interval 5 mm, and reconstructed section thickness 1.25 or 2 mm.