ABSTRACT
The incidence of rectal cancer gradually increased in our country in recent years.Preoperative imaging methods are used to accurately display the lesions of rectal cancer,providing accurate quantitative diagnostic information,therefore being important to formulate reasonable and individualized therapy clinically.Intra-voxel incoherent motion (IVIM) is a multi parameter imaging technology.IVIM can provide the diffusion and perfusion information from the molecular level.Theoretically,the microstructure information of internal rectal cancer cell density and the vascular density,and the tumor cell metabolism can be displayed quantitatively with IVIM imaging,which can reflect the heterogeneity of the tumor and its degree during different periods.The application status and the future development of IVIM technique in management of rectal cancer were reviewed in this article.
ABSTRACT
Objective To investigate the feasibility of reducing the radiation dose in adult pelvic CT using automatic tube current modulation (ATCM) and adaptive statistical iterative reconstruction (ASIR).Methods Totally 45 patients who underwent routine and low-dose pelvic CT examination were enrolled in our study.Three groups of images were acquired:group A (routine scan with FBP reconstruction) ;group B1 (low-dose with ASIR0) and group B2 (low-dose with ASIR50％).The scores of image quality was abtained by two radiologists.Results The CTDIvol,DLP and E of group B were significantly reduced respectively(t =12.30,12.10,12.15,P ＜ 0.05) compared with group A.Group B1 had higher noise(t =9.14,8.95,P ＜ 0.05)and lower score,SNR and CNR(t =8.72,10.62,11.83 and 8.40,9.55,11.42,P ＜ 0.05) than the others.And there was no difference in image quality between group A and group B2.Conclusions Using automatic tube current modulation and adaptive statistical iterative reconstruction could significantly reduce the noise but keep the image quality in adult pelvic CT examination.
ABSTRACT
Objective To explore the value of vertical to clivus CT scanning in diagnosing tentorial hernia and to analyze the CT findings of tentorial hernia in the patient with brain trauma. Methods Vertical to clivus CT scaning were performed in 156 cases with brain trauma.Results Vertical to clivus scanning method directly demonstrated the temporal transtentorial hernia in 72 of 156 patients with unilateral high intracranial pressure, but the orbitomeatal line scanning method was not able to show this direct finding. The CT findings of hernia were the tissue of temporal lobe appeared in the cisterna ambiens inside the tentorium accompanied by enlarged cistern on the involved side. No change of cistern were seen in 84 cases.Conclusion The scanning method with vertical to the clivus is effective in detecting tentorial hernia in the patient with cerebral trauma, it should be performed in the patient with cerebral trauma and increased intracranial pressure.