Objective To evaluate the application value of combination of low kV,low mAs,and iterative model reconstruction (IMR) in carotid CT angiography.Methods Forty patients (BMI 20-25 kg/m2) were enrolled and randomly divided into routine dose group(20) and low dose group(20),The parameters in routine dose group were 120 kV,automatic mAs,and filter back projection(FBP);and that in low dose group were 80 kV,automatic mAs but upper limit 150 mAs,and FBP or IMR.All patients received the injection of 32 ml of iopamidol(370 mg I/100 ml) at a flow rate of 4 ml/s,followed by 50 ml normal saline at the same rate.The CT value and image noise(SD)of the aortic arch,left carotid artery bifurcation,and right carotid artery of rock bone were measured with region of interest(ROI) method,and then signal to noise ratios (SNR) and contrast to noise ratio (CNR)of image were calculated.The image quality was evaluated by two radiologists using a subjective four points scale on multiplanar reformated (MPR),maximum density projected (MIP) and volume rendered (VR) images.Volume CT dose index (CTDIvol),dose length product (DLP),and the effective dose (E) of each patient were recorded.Results CT values of carotid artery[(479.87 ± 70.28),(514.78 ± 82.69),(436.50 ± 89.87) HU] in low dose group were significantly higher than those in routine dose group [(295.63 ± 34.75),(325.09 ± 37.81),(286.93±36.46)HU](t =-6.47,-5.76,-3.66,P＜0.05).The SNR and CNR of IMR reconstructed image in low dose group were significantly higher than those of FBP reconstructed image in routine dose group (t =-7.54,-3.55,-5.31,-7.13,-5.28,-8.35,P＜0.05).The image quality of FBP reconstructed images in routine dose group and IMR reconstructed images in low dose group were all enough for diagnosis.The image quality of FBP reconstructed images in low dose group was significantly poorer than that in routine dose group and IMR reconstructed images in low dose group (Z =-2.87,-3.69,P ＜0.05).The effective dose in low dose group (0.57 ±0.13) mSv was 73％ less than that in routine dose group (2.22 ± 0.36) mSv.Conclusions Using low kV,low mAs,and IMR would help to obtain good carotid CT angiographic images and low radiation dose.

Giant intracranial aneurysms refers to the diameter of aneurysms larger than 2.5 cm,which belongs to the complicated aneurysms,accounting for about 5％ ofintracranial aneurysms;rupture of the aneurysms leads to extremely high disability rate and fatality rate.At present,surgical treatment,endovascular treatment and new composite (hybrid) surgery are the three major surgical approaches.We summarize the treatment approaches to promote an update on treatment of such aneurysms and give understanding on the development and direction of aneurysm treatment.

BackgroundVestibular neuritis is a common clinical acute peripheral vertigo disorder. Some patients may experience negative emotions states， leading to chronic exacerbation of vestibular neuritis and a poorer prognosis. Further research is needed to understand the psychological state of patients with vestibular neuritis and its influencing factors. ObjectiveTo explore the relationship between depressive symptoms and vestibular symptoms in patients with vestibular neuritis and its influencing factors， so as to provide references for clinical intervention. MethodsA total of 86 patients with vestibular neuritis， hospitalized in the Department of Neurology of the Third Hospital of Mianyang from June 2021 to June 2023， were included in the study. Assessments were conducted using the Hamilton Depression Scale-17 item （HAMD-17）， Dizziness Assessment Rating Scale （DARS） and Dizziness Handicap Inventory （DHI）. Patients were divided into depression group（n=46） and non-depression group（n=40） based on HAMD-17 score. Pearson correlation analysis was used to examine the correlation among each scale score. Binary Logistic regression was used to identify influencing factors for depressive symptoms. ResultsAmong the 86 patients， 46 （53.49%） exhibited depressive symptoms. Statistically significant differences were observed between depression group and non-depression group in terms of age， disease duration， years of education， DARS score and DHI score （t=4.512， 4.921， 2.712， 3.529， 5.471， P<0.01 ）. In depression group， HAMD-17 score was positively correlated with DARS score and DHI score （r=0.345， 0.335， P<0.01）. Binary Logistic regression analysis showed that age （OR=4.352， 95% CI： 1.520~12.462）， disease duration（OR=3.772， 95% CI： 1.339~10.630）， years of education （OR=0.074， 95% CI： 0.235~0.923）， DARS score （OR=1.213， 95% CI： 0.405~3.628） and DHI score （OR=3.619， 95% CI： 1.246~10.514） were the influencing factors of depressive symptoms among patients with vestibular neuritis. ConclusionDepressive symptoms in patients with vestibular neuritis are positively correlated with vestibular symptoms. Risk factors for depressive symptoms in patients with vestibular neuritis include age， disease duration， DARS score and DHI score， while years of education serve as a protective factor.