ABSTRACT
Objective To explore the feasibility of one-stop examination with Revolution CT for axial perfusion of normal pancreas.Methods Thirteen patients who received axial perfusion scan by one-stop examination with Revolution CT were analyzed as perfusion group.Two radiologists measured pancreatic CT perfusion (CTP) parameters independently and selected optimal phase for CTA and three phases of enhanced images.The effect dose (ED) was calculated.Eighteen patients who underwent abdominal enhanced CT and CTA with spiral scan were included as control group.Patients in both groups had no pancreatic disorders.The interobserver variation of CTP parameters was estimated.Two independent radiologists separated the superior pancreaticoduodenal artery (SPDA) image into 5 points according to image quality,and the consistency was assessed.The subjective points of SPDA image quality of two groups was compared.CT value,images noise,CNR and SNR of SPDA on CTA images and those of pancreas on three phases enhanced scan images between two groups were compared.Results ICC values of all CTP parameters were higher than 0.75.The ED of perfusion protocol was (24.52±-0.01)mSv.The subjective image scores of SPDA on CTA images in both groups were both 5,the consistency was good (Kappa=0.629,0.769).The CT value,CNR,and SNR of SPDA on CTA images of CTP group were higher than those of control group (all P＜0.05).The CT value,CNR,and SNR of pancreas of CTP group were higher than those of control group in venous phase and balanced phase (all P＜0.05).Conclusion The pancreatic CT one-stop examination can be performed by Revolution CT scanner with maximum detector width with acceptable radiation dose,from which pancreatic CT perfusion data,enhanced images with high quality and better CTA images can be extracted.
ABSTRACT
Objective To explore the effect of whole renal perfusion imaging removal of arterial phase data on perfusion parameters of renal clear cell carcinoma using Revolution CT.Methods Perfusion imaging with Revolution CT was retrospectively analyzed in 10 patients with pathologically proven clear cell renal cell carcinoma.The z-direction coverage model was used in perfusion imaging,and the images were analyzed with CT Perfusion 4D software.All images were analyzed twice.All 23 phases data was included in group A and only 16 phases except arterial data (9-15 phases) were selected in group B.The abdominal aorta on the level of right hilus was chosen to be the input artery,and the perfusion parameter maps were obtained,including blood flow (BF),blood volume (BV),mean transit time (MTT),permeability of surface (PS).Every perfusion parameters of lesions and contralateral normal cortex,lesions and normal cortex in both groups were compared.Results The BF and PS of lesions were lower than those of normal cortex in both groups (both P＜0.05).There was no statistical difference in BV and MTT between lesions and normal cortex in both groups (all P＞0.05).There was no statistical difference in all perfusion parameters of renal clear cell carcinoma between group A and group B (all P＞0.05).The difference of BF in normal cortex between the two groups was statistically significant (P 0.009),and the difference of the PS,BV,MTT had no statistically significant (all P＞0.05).Conclusion When the duration time of renal CTP is 600 s,there is no difference between including and excluding arterial phase in all perfusion parameters of renal clear cell carcinoma.
ABSTRACT
Objective To explore the feasibility of axial whole-liver one-stop examination with Revolution CT.Methods Totally 19 patients were underwent upper-abdominal enhanced examination with Revolution CT and acquired whole-liver CT perfusion (CTP),vein phase and balanced phase enhanced images.Two observers recorded the rank and peak CT value corresponding to time-density curve (TDC) of abdominal aorta and portal vein respectively on the CTP images.The perfusion parameters including blood flow (BF),blood volume (BV),hepatic arterial fraction (HAF),mean transit time (MTT),time to peak (TP) of left and right liver lobe were measured.The images of hepatic artery CTA and portal vein CTV were reconstructed and the arterial phase enhanced images were extracted using the images corresponding to abdominal aorta and portal vein peak TDC.And the radiation dose of CT perfusion and one-stop examination were recorded.The differences between perfusion parameters of left and right liver lobe were compared and the consistency of two observers were analyzed.Results The differences between BV and MTT of left and right liver lobe were statistical significance (both P＜0.05).The subjective scores of hepatic artery CTA,portal vein CTV and arterial phase images were greater than 1 point.The two observers were in great consistence (Kappa＞0.6).The effective radiation dose in perfusion phase and one-stop examination were 14.47 mSv and 21.29 mSv.Conclusion With low radiation dose,Revolution CT axial wholeliver perfusion one-stop examination can provide multiple quantitative parameters of liver CTP and clear hepatic artery CTA,portal vein CTV and 3 phase enhanced scan images,which has broadly prospective in clinical application.
ABSTRACT
Objective To investigate the features of CT perfusion (CTP) parameters of adrenal adenoma (AA) using wide detector CT.Methods The wide detector CT scanning data of 21 patients with pathologically confirmed AA were retrospectively analyzed.CT perfusion (CTP) imaging was performed with the axis mode covering by 16 cm detector and ASiR-V50％.The image acquisition of CTP was performed after 6 s of injection of contrast media.Totally 26 consecutive volume acquisitions were contained.The arterial,venous and delayed phase images were obtained at the time of 22 s,51 s and 153 s after the injection,respectively.The blood flow (BF),blood volume (BV),mean transit time (MTT),time to peak (TP) and permeability of surface (PS) values of AA (group A) and contralateral normal adrenal gland (group B) were measured.All parameters between the two groups were compared,and the radiation dose was assessed.ROC curves were used to assess the diagnostic efficiency of CT perfusion parameters for AA.Results BV,MTT and PS values of group A were statistically lower than those of group B (all P＜0.05).There was no statistical difference of BF and TP values between the two groups (both P＞0.05).The area under the ROC curve (AUC) of BV,MTT and PS was 0.780,0.762 and 0.831,respectively.The sensitivity and specificity of diagnosis of AA was 95.2％ and 81.0％,respectively,when the threshold of PS was 1.37 ml/(100g · min).The effective dose (ED) of CT plain and CTP (including three-phase enhanced scan) were (3.20 ± 0.57) mSv and (19.98 ± 1.95) mSv.Conclusion Wide detector CT perfusion imaging can provide high-quality conventional three-phase enhanced images for diagnosis of AA,and provide effective quantitative perfusion data at the same time.PS value shows strong capability for diagnosis of AA.