Objective To identify the optimal mono-energetic enhanced spectral CT for renal cortex in cortical phase based on the iodine concentration. Methods Fifty patients with normal renal function received the abdominal enhanced spectral CT examination.The iodine concentration and CT values of the multiple mono-energetic spectral images were measured on renal cortex in cortical phase,and the correlation between the iodine concentration and the CT values and the coefficient of variation(CV)were analyzed. Results The correlation analysis demonstrated that the correlation coefficient was 0.994,0.994,0.993,0.987,0.976,0.960,and 0.938 between mono-energetic spectral CT images(40-100 keV with interval 10 keV,respectively)and iodine concentration(all
Contrast Media ; Humans ; Iodine ; Kidney Cortex/diagnostic imaging* ; Radiographic Image Interpretation, Computer-Assisted ; Tomography, X-Ray Computed

OBJECTIVETo evaluate perfusion characteristics of normal renal cortex with 64-slice spiral CT and to investigate the correlation between perfusion parameters and gender, age, and serum creatinine (Scr).

METHODSIn total 71 healthy subjects, the kidney non-enhanced imaging and perfusion imaging with 64-slice spiral CT were performed. Perfusion parameters of renal cortex including blood flow (BF), blood volume (BV), and permeability (PM) were calculated with Siemens Body PCT (VB20B) software. The differences of BF, BV and PM in different age and gender people were compared by one-way ANOVA. The correlation between age and perfusion parameters, Scr, and PM were analyzed.

RESULTSTechnical failures were experienced in 3 (3/71, 4.2%) subjects. Perfusion values of normal renal cortex in male, female, and all subjects were obtained separately. Male subjects (n = 56): BF = (229.8 +/- 49.9) ml/(100 ml x min), BV = (398.2 +/- 59.5) 1000:1, PM = (213.5 +/- 54.0) 0.5 ml/(100 ml x min); female subjects (n = 52): BF = (230.0 +/- 56.1) ml/(100 ml x min) BV = (358.1 +/- 49.7) 1000:1, PM = (186.2 +/- 32.1) 0.5 ml/(100 ml x min); all subjects (n = 108): BF = (229.9 +/- 52.7) ml/(100 ml x min), BV = (378.9 +/- 58.4) 1000:1, PM = (200.4 +/- 46.7) 0.5 ml/(100 ml x min). There was no significant difference in BF (F = 0.367, P = 0.547), BV (F = 3.088, P = 2.762), and PM (F = 3.308, P = 0.074) between male and female. In male, female, and all subjects, BF were all negatively correlated with age (r = -0.484, r = -0.429, r = -0.425; P < 0.01), while there was no correlation between BV (r = -0.152, r = -0.243, r = -0.043, P > 0.05) and PM (r = 0.053, r = 0.123, r = 0.172, P > 0.05) and age. There was no correlation between PM and Scr (r = 0.064, P > 0.05).

CONCLUSIONThe measurement of normal renal cortical perfusion characteristics with 64-slice spiral CT is feasible and can be used for the quantitative evaluation of the physiological functions of normal renal cortex.

Adult ; Aged ; Female ; Humans ; Kidney Cortex ; blood supply ; diagnostic imaging ; physiology ; Male ; Middle Aged ; Perfusion Imaging ; methods ; Reference Values ; Tomography, Spiral Computed ; methods ; Young Adult