16 slice brilliance big bore ct

From January 2014 to December 2014, 16 patients were selected from an ongoing prospective phase II study of S-1 based ACRT for locally advanced adenocarcinomas of the GEJ and the stomach. A total dose of 45 Gy (1.8 Gy/fraction, 5 days/week) was delivered. S-1 was administered every weekday at a dosage of 80 mg/m²/d, based on results of our previous phase I study [29 ]. Patient characteristics were presented in Table 2. According to the 7th edition of the American Joint Committee on Cancer staging system [30 ], five patients with GEJ cancer were at stage III, and two and nine patients with stomach cancer were at stage II and III, respectively.
The patients were placed in a supine position with thermoplastic immobilization. Intravenous contrast-enhanced CT simulation was performed at 5-mm intervals with a 16-slice Brilliance Big Bore CT (Philips Medical Systems, Cleveland, OH). In all patients, the CT scan was performed from the 6th cervical vertebra to the 5th lumbar vertebra.
As this was an in silico planning experiment without actual treatment, data were derived from our ongoing clinical phase II study, which was approved by the ethics committee of our hospital and was registered in clinicaltrials.gov (NCT02312284).

Three types of image data were involved in this study, including planning CT images, three-dimension dose distribution images, and organs-at-risk (OAR) structures. All planning CT images were acquired from a 16-slice Brilliance Big Bore CT (Philips Medical System, Cleveland, OH, U.S.). The scanning parameters were as follows: scanning X-ray tube voltage = 120 kV, current = 321 mA, thickness = 3 mm, slice pixels = 512 × 512 and spacing = 1.152 mm × 1.152 mm. The scanning range was from the level of the cricoid cartilage to the lower border of the 12th thoracic vertebra covering the WL volume (Bradley et al., 2020 (link)). The 3D dose was calculated with a grid of 3 mm in the treatment planning system (TPS). The gross tumor volume was excluded from the lung volume with manually contouring by a qualified physician.

The study has been reviewed and approved by the institutional review board (No. 2019[240]). We retrospectively collected 11 thoracic 4D computed tomography (CT) scans from our institution, of which 10 were stamped with respiratory motion phases (patients 1–10) and 1 was stamped with cardiac motion phases (patient 11). All had received 2 thoracic 4D‐CT scans, first without and with intravenous contrast immediately thereafter. The thoracic respiratory 4D‐CT images were taken on a 16‐slice Brilliance Big Bore CT (Philips Medical Systems, Cleveland, OH, USA) and respiratory motion was traced by a pressure sensor belt. Each 4D‐CT image consists of 10 phases 3D‐CT datasets equally divided 10% of breathing phases in a complete respiratory cycle. Cardiac‐gated 4D‐CT images were taken on a 64‐slice scanner (GE Healthcare, Waukesha, USA) at the end‐expiration breath‐hold using retrospective cardiac gating and also reconstructed 10 phases of cardiac cycle. For all patients, CT simulation was performed at 3‐mm intervals.