64 slice spiral ct machine

Both groups of patients used the 64-slice spiral CT machine produced by GE in the USA for enhanced CT examination. First, a plain scan was performed on the patient's upper abdomen with a voltage of 120 kV, a tube current of 600 mA, and an interval of 0.965. A biphasic (arterial phase and portal vein phase) dynamic enhancement scan was performed on the patient's upper abdomen. 100 mL of iopromide injection (approval number J20100030, Guangzhou Branch of Bayer Healthcare Co., Ltd.) was injected into the patient's cubital vein at a rate of 3 mL/s. At 30 s and 60 s after the start of the contrast agent injection, the patient was instructed to hold his breath and scan in the arterial phase and portal vein phase. The patient's CT image was reconstructed. All data are reconstructed with 2 mm layer thickness and 1 mm interval, and then transferred to the background workstation. The incoming images are processed accordingly.

Prodigy Advance DXA instrument from GE-LUNAR corporation was used to detect BMD. Then, T-scores were calculated based on BMD. According to the criteria of World Health Organization (WHO) [22 (link)], any T scores at total hip, lumbar spine, or femoral neck BMD ≤ − 2.5 were used to define osteoporosis; T scores < − 1 and > − 2.5 were used to define osteopenia. Presence of a fragility fracture was also diagnosed as osteoporosis, which was defined as low-impact fracture (resulting from a fall from a standing height or less or occurring in the absence of trauma) [23 (link)]. Besides, the 64-slice spiral CT machine from GE corporation and the 5-sample solid phantom from Mindways were also used to measure a proportion of participants’ BMD. The original images were analyzed by Mindways quantitative computed tomography (QCT) Pro software. According to the criteria of the International Society for Clinical Densitometry (ISCD) [24 (link)], trabecular volumetric BMD (vBMD) values of 120 mg/cm³ and 80 mg/cm³ are often used as thresholds to define osteopenia and osteoporosis.