Purpose To investigate the chest CT features of lung injury caused by oral paraquat,and deepen the understanding of paraquat poisoning.Materials and Methods The chest CT features of 74 patients with lung injury caused by oral paraquat were analyzed retrospectively and comparatively.74 patients were divided into 3 groups according to toxic dose:28 cases in the low dose group (paraquat dose less than 10 ml),34 cases in the medium dose group (paraquat dose among 11 to 50 ml),and 12 cases in the large dose group (paraquat dose more than 50 ml).74 patients were also divided into 3 groups according to course of disease:The course of disease among 1 to 7 days were in the early period,8 to 14 days in the medium period,and 14 days later in the later period.The image features were summarized by comparing the chest CT features,with toxic dose,course of disease,and the scope of lung injury.Results Poisoned patient's chest CT features,related with toxic dose (P＜0.05),appeared from increased bronchovascular shadows,ground glass opacity,to effusion and consolidation,and to pulmonary fibrosis along with time.The effusion and consolidation majorly located in the lateral lungs,which showed a characteristic disease extent.Conclusion The chest CT features of lung injury,caused by oral paraquat,have a certain characteristic.It relates to toxic dose and course of disease,which has a certain guiding significance to clinical diagnosis and treatment.

Objective　To analyse the CT appearance of ependymomas and to improve the accuracy of diagnosis. Methods　To review the CT appearance of 15 cases of ependymoma that confirmed by surgery and pathology. Results　12 cases were superior, 8 cases were brain parenchyma among of them; 3 cases were subtentorial, among them the fourth ventricle 2 cases. The age of 6 cases vary from 20 to 35 years. Ependymomas superior to the tentorium in the brain parenchyma were the most common, and in malignant parts there were cystoid changes and edema around the tumor. In the other parts were largely solid neoplasm. On unenhanced CT, the solid parts were indense and caicificable and were easy to dicern on enhanced CT . Conclusion　The CT appearances of ependymoma were specific, we can dram an accurate conclusion according where the tumor taking place, the age etc.

Purpose To evaluate the feasibility of magnetic resonance T2 values in diagnosing hepatic fibrosis (HF).Materials and M1etdheds The models of HF were induced in rats by repetitive dosing of carbon tetrachloride.The stage of hepatic fibrosis (S),grade of inflammation (G) and degree of fatty liver (F) for the HF model animals and their normal controls were evaluated by pathology.The relationship between T2 values and liver fibrosis was analyzed by using multiple echo gradient spin echo sequences.Results According to the stage of hepatic fibrosis,the HF model rats were staged into S1-S4.The grade of inflammation of the HF model rats was G0 or G1,and the degree of fatty liver was F3 or F4,both of which had no statistical differences among the HF model rats at different fibrosis stages (P＞0.05).The T2 values for all rats including normal control rats in the stage of liver fibrosis from S0 to S4 were (38.27±1.45) ms,(42.08±2.63) ms,(45.93±3.61) ms,(50.23 ± 2.23) ms and (57.79± 5.40) ms,respectively,with a significant difference (F=31.903,P＜0.01).Except the T2 values had no significant difference between the S0 and S 1 stages (P＞0.05),the pairwise comparisons of the T2 values between the rest stages were statistically significant (P＜0.01).The T2 values were positively correlated with the stages of hepatic fibrosis (rs=0.921,P＜0.01).Conclusion The T2 value can quantitatively reflect the degree of hepatic fibrosis.

Objective To observe and analyze the standards of the normal vivo renal multi-slice spiral CT(MSCT) imaging to provide relevant normal range for clinic and teaching.Methods 123 cases with normal kidneys were undergone abdominal MSCT,then 3D imaging was performed,the position of kidney distance between two poles of kidney and the central line of the spine,renal length and short axis,the angels between the renal length axis and sagittal segment(LS) and the coronal segment(LC),the angel between coronal segment and the longest distance line from the midpoint of the renal gate to the same kidney's out edge(CL) were observed and measured with statistics analysis.Results Mostly the position of left kidney was higher than that of the right.Almost kidney's upper poles located at the T12 level.The number of left kidney was more than the right kidney in the renal upper pole located higher than T11.Almost kidney's inferior poles located at from the L2 inferior edge level to the L3 inferior edge level.In the statistic results,the values measured on CT of left kidney were large or equal to the right except for CL and LC in men,LC in women,total LC and LS.The width in men,total length and width and total upper distance were of significant statistics meaning(P

Objective To study the factors effect on the measurement of CT value.Methods CT water phantom was scanned using the regular condition of scaning first,then changed one of scaning conditions (thick slice, exposure capacity, reconstruction of function, kV, FOV and CT-scanner) to scan the water phantom again. The CT value (mean?SD) of image region of interest (ROI) was compared in two conditions. Results The mean CT value in the opposite ROI in thick slice 5mm and exposure capacity 150 mAs was similar to that in thick slice 10mm and exposure capacity 300mAs, the reconstruction of function Fc80 was lower Fc10 , the 130kV was distinct higher 120Kv in mean of CT value respectively.The SD(noise) in thick slice 5mm was near to the exposure capacity 150mAs, while in contrast to the thick slice 10mm and the exposure capacity 300mAs was obvious increased , but the reconstruction of function Fc80 was distinct higher Fc10, the 130kV was slightly lower 120Kv in SD(noise) respectively . All of mean CT value and the noise in the small field were higher in the middle field ,when CT imaging in the water phantom of the single small field .This result was also received when the old Toshiba CT-scanner was compared with the new GE CT-scanner in the differ water plantom.Conclusion The CT value is not constant and can’t act as a diagnostic standred.

Objective To explore the application value of ECG tube current modulation technology of dual source CT in coronary angiography,compared with retrospectively ECG-gated technique.Methods 200 patients were randomly divided into ECG tube current modulation group (Group A)and retrospectively ECG-gated group(Group B).In Group A,the main parameters were the exposure time windows of full dose,which were set according to different heart rates.χ2 test was adopted in the subjective score,and t test was used in the objective score and radiation dose.Results There was no statistical significance in image quality between the two groups(χ2 =2.125,tnoise =-0.557,P >0.05 );The effective dose (ED)of Group A and Group B were (3.30±0.40)mSv and(6.90±1.76)mSv,respectively.The difference was statistically significant (t ED =-1 9.954,P <0.05).The radiation dosage of Group A was 52% lower than that of Group B.Conclu-sion Compared with retrospectively ECG-gated technique,the ECG tube current modulation technique ensures the image quality, and at the same time it can significantly reduce the radiation dose,therefore,it can be used as a routine examination technique of cor-onary angiography.

Objective To investigate thickness of the hilar periportal space and caudate-right lobe ratio in the patients with chro-nic hepatitis B and liver cirrhosis after hepatitis B .Methods Eighty-four patients who were clinically and histologically diagnosed with chronic hepatitis B or cirrhosis and 18 healthy subjects without history of liver disease underwent abdominal MRI .The rela-tionship among liver fibrosis degree ,hilar periportal space and caudate-right lobe ratio were observed .Results There was signifi-cant correlation between the hilar periportal space and hepatic fibrosis for chronic hepatitis and cirrhosis (rs = 0 .546 ,P< 0 .01) . There was significant difference between S2 and S3 for thicknesses of the hilar periportal space(P<0 .01) ,and no significant differ-ence among S3 ,S4 and cirrhosis(P=0 .188) .A cutoff value of 9 mm for the hilar periportal space had a sensitivity of 85 .37% and a specificity of 76 .79% for a diagnosis of hepatic fibrosis with S3 or higher .There was no significant correlation between the caudate-right lobe ratio and hepatic fibrosis(rs = -0 .155 ,P=0 .119) .Conclusion Thicknesses of the hilar periportal space increase gradu-ally with hepatic fibrosis in patients with chronic hepatitis B and cirrhosis ,with a high sensitivity and specificity for a diagnosis of hepatic fibrosis with S3 or higher .

Objective To explore the localization diagnosis method of lumbar intervertebral foramen stenosis by multi-di-mensional MRI scans of lumbar nerve roots. Methods Twenty-one patients with lumbar intervertebral foramen stenosis were fol-lowed up from June 2006 to June 2011 postoperatively, 10 cases of male, 11 cases of female;36 to 65 years old, average 45.6 years. The medical history is six to thirty six months, an average of 9.4 years;5 cases have low back pain with unilateral leg pain and 16 cases showed unilateral leg pain only. The height of intervertebral space and foramen intervertebrale were measured on the X-rays of lumbar lateral position. Lumbar nerve roots MR imaging at the position of axial, coronal and sagittal scan were performed separately to the patients who were clinically suspected to suffer from lumbar intervertebral foramen stenosis. A definitive diagno-sis of the location of nerve root compression and structural changes surrounding the nerve root can be obtained. Surgical operation was performed to confirm the accuracy of the MRI imaging diagnosis. Results There were 9 cases of lumbar intervertebral fora-men stenosis caused by lumbar disc herniation. The other 12 cases are caused by zygapophyseal joint hyperplasia. All cases of lumbar intervertebral foramen stenosis located at the low back. By comparing MR images of lumbar intervertebral foramen stenosis with surgical procedure,the surgical observation of 21 patients completely coincided with the preoperative localization diagnosis, coincidence rate was 100%(21/21). After surgical treatment, 20 cases achieved a complete remission of leg pain and 1 case was not satisfactory. Conclusion MRI imaging at the position of axial, coronal and sagittal scan for lumbar nerve roots were useful to rigorous localization diagnosis of lumbar intervertebral foramen stenosis, and can provide accurate radiological evidence for sur-gery program.

Objective To observe and measure the anatomical structure of approach of vertical facial nerve canal and put forward the normal measurement range and the location relationship among the vertical segment of facial nerve canal, the posterior wall of external acoustic meatus and the rear edge of external ear,and discuss the relationship and clinical significance between the mastoid gasification and the vertical segment of facial nerve canal. Methods 1. Evaluate the accuracy of CT image of related structure, using spiral CT in scanning four skull specimens, get the horizontal distances of the vertical segment of facial nerve canal to the posterior wall of external acoustic meatus and the rear edge of external in the axial position, and get the sagittal diameter of mastoid (the horizontal distance from the lowest point of external auditory inferior canal to the rear edge of mastoid) and the height (the vertical distance between the lowest points of the external auditory canal wall to the mastoid tip) in the sagittal position. And then saw the skull specimens to measure the distance in the same lay with CT image, and discuss the statistics difference of the distance between the values of CT imaging measurements and the dry entities cranial measurements on hand. 2. Study on people: 118 patients (236 sides) with non-ear disorders were randomly selected, among which there were 63 females (126 sides) and 55 males (110 sides). They were subjected to maxillofacial CT scan in the same layer that used above, and the horizontal distances of the facial nerve canal to the posterior wall of external acoustic meatus and the rear edge of external ear were measured. In addition, half of the product of diameter and height of the mastoid was defined as mastoid area, which was used to define the extension of mastoid gasification. Then related analysis and regression analysis were done between the vertical segment of facial nerve canal and the posterior wall of external acoustic meatus, as well as the rear edge of external ear. Results 1.Part of the experiment: There was no significantly different on the indicator values between CT image the entity measurements among the four skull specimens (P>0.05). 2. Study on people: There was no significantly different between left side and right side(P>0.05), but significantly different between genders(P<0.05). Between mastoid area and the distance from the vertical segment of facial nerve canal to the posterior wall of external acoustic meatus there is inverse correlation, and the relevance has the remarkable significance. However, there was no correlation between mastoid area and the vertical segment of facial nerve canal to the rear edge of external ear. Conclusion There was some relationship between the location of the vertical segment of facial nerve canal and external acoustic meatus. Anatomic position of vertical facial nerve cancal and the posterior wall of external acoustic meatus can be showed clearly. CT and in combination with primitive axial images may provide reliable evidence for the diagnosis facial nerve dieases and the choice of ear surgery route.

Purpose To explore the value of 64-slice spiral CT digital subtraction angiography in diagnosis of cerebral arteriovenous malformations (AVM).Materials and Methods 26 patients with AVM were performed with plain CT scan, enhanced arterial phase and venous phase CT scan on a 64-slice spiral CT scanner. The subtracted arterial phase data was obtained through subtracting the plain CT images from arterial phase images, then the subtracted venous phase data was obtained through subtracting arterial phase images from venous phase images, and subtracted mixed arterial-venous phase data through subtracting plain CT images from venous phase images. Then volume rendering (VR) and maximum intensity projection (MIP) were used to reconstruct the cerebral vessel images. Results The inference of cranial bones was completely removed in all subtracted cerebral vessel images, thus clearly demonstrating malformed vascular nest, feeding arteries and draining veins. And 7 malformed temporal vascular nests, 5 parietal vascular nests, 5 frontal vascular nests, 6 occipital vascular nests and 3 cerebellar vascular nests were revealed;39 feeding arteries were detected altogether. Single feeding artery was found in 15 cases, and multiple feeding arteries in 9 cases. Meanwhile 33 draining veins were observed, and single draining vein was found in 10 cases, multiple veins in 16 cases.Conclusion 64-slice subtraction angiography can remove the inference of cranial bones and clearly demonstrate the feeding arteries, malformed vascular nests, draining veins, potentially providing a reliable evidence for therapeutic planning and postoperative follow-up.