ABSTRACT
Objective To study the effects of different temporal resolution of spiral computed tomography (CT)on perfusion parameters and perfusion curve of cervical cervical cancer.Methods Ten cases of cervical cancer were clinically confirmed with CT perfusion scanning.The original data were acquired using temporal resolution of 0.75 s.Then the original data were grouped according to different temporal resolution,namely,1.5 s group,2.25 s group,3 s group,3.75 s group,4.5 s group,5.25 s group,and 6 s group (experiment group). According to the same mathematical model and ROI of the same part,perfusion parameters (BF,BV,MTT,and PS)in each group were calculated respectively and compared with the original data.Results BF and MTT were relatively sensitive to the change of temporal resolution.When the temporal resolution was 3 s,it had a significant impact.PS and BV were not so sensitive to the change of temporal resolution.Temporal resolution of 4.5 s had a significant effect on PS. There was a significant effect on BV until the temporal resolution was 5.25 s. Conclusion Changing the temporal resolution will lead to corresponding changes of perfusion curve and perfusion parameters.Under the premise that it does not affect the diagnosis,properly decreasing temporal resolution (circu-lar scanning temporal ≤2.25 s)of CT perfusion scanning of cervical cancer can reduce the radiation dose effectively.
ABSTRACT
Objective:The abstraction of characteristics in CT perfusion image is crucial in the clinical diagnosis of brain infarction and cerebral tumor.Methods:After describing the relevant parameters of CT cerebral perfusion imaging,such as cerebral blood flow (CBF),cerebral blood volume (CBV),the mean transition time (MTT) and the permeability surface (PS).With using Visual C ++ programming and CT scan images sequence obtained,the time-density curves of the brain tumor region were visualized.The more accurate hemodynamic parameters were calculated through an improved algorithm basing on the deconvolution and measuring method of the length,angle,area and other parameters.Conclusion:The quantitative analysis of feature parameter is of great benefit to clinical doctor in making timely diagnosis and treatment of brain tumor.