Objective To analyze the clinic and imaging characteristics as well as development of intervertebral disc calcification in children.Methods 6 cases underwent intervertebral disc calcification.X-ray films and CT scan of cervical spine had been taken in all cases,two cases had MRI examination.All cases were followed-up for 2 to 3 years by radiograph and CT.Results Only one intervertebral disc involved in all cases.X-ray and CT findings included disc calcification,disc herniation and change of vertebral boy in form.The clinical symptoms disappeared after conservative therapy 2 to 4 weeks.But the disc calcification disappeared until 6 months to 3 years.Conclusion Intervertebral disc calcification in children is a self-limiting disease with excellent prognosis,its diagnosis depends on imageology.

Objective To evaluate the usefulness of combined three-dimensional (3D) and two-dimensional (2D) contrast enhanced magnetic resonance angiography (CE-MRA) for checking the thrombus embolism of different positions within single examination on the pulmonary artery and pelvic-lower limb deep veins. Methods Fifteen patients with suspected pulmonary embolism and pelvic-lower limb deep venous thrombosis (DVT)were evaluated with combined 3D MRA and 2D CE-MRA. 3D spoiled gradient-recalled-echo bolus chase MR angiograms were obtained in four stations from the pulmonary artery to the ankle. Thereafter,3D CE MRA was reversely scanned from the ankle to the pelvic. 2D contrast-enhanced MRI was obtained in pelvis, thigh, and calf. Pulmonary CT angiography (CTA) and/or DSA were performed in 15 patients,and duplex ultrasonography of lower-limb vein was performed in 12 patients. Results Of the 15 cases, acceptable imaging of pulmonary vessel was acquired with 3D CE-MRA in 12 cases. The signal intensity was lower in the deep iliac vein and lower extremities than that in the artery, but vein frame was distinct after post processing. The artery and deep vein were clearly revealed with contrast enhanced FSPGR sequence in 15 cases. 3D CE-MRA imaging disclosed pulmonary embolism in fourteen patients and pelvis-lower limb DVT with multi-place involvement in nine patients. 2D contrast-enhanced MR imaging proved DVT in pelvis-lower limb. 2D contrast-enhanced FSPGR sequence was a complementation of 3D CE-MRA and it had larger scan field. Thrombus presented as low signals and eccentral or intraluminal filling defect. Local caliber of vein thrombus in 6 cases was evidently broadened. Conclusion Within only one MR examination procedure, it is capable of examining the pulmonary embolism and DVT of pelvis-lower limb with combined 3D MRA and 2D contrast enhanced MR. The results are promising as a non-invasion "one-stop shopping" tool in the evaluation of thromboembolic disease.

Objective To investigate the variations of multi-segments of the Willis' circle in cases with ACA-A1 variation.Methods Retrospective comparative analysis was applied to images of 2 246 healthy cases which were excluded from abnomalities of physical and biochemistry examination and angiostenosis caused by angiosclerosis.We divided variant group and contrast group according to variation of ACA-A1 segment.Several aspects were carried to comparison:the variation between bilateral ACA-A1 segment within the variant group was studied by x2 test; the proportion of FTP and developing of PCA-P1 were put into test.Finally we use trend x2 test to compare the variation degree of ACA-A1,ipsilateral FTP formation and PCA-P1 variation.Results Variants of ACA-A1 contains 634 cases whereas normal cases were 1 612.A prominence in variation revealed in right side of ACA-A1 (x2=26.19,P＜0.01) which revealed by 429 cases in right side versus 205 cases in lefi side respectively.Parallelled with contrast group,the variant group showed immensely advantages in high proportion of FTP (x2=14.165,P＜0.01) which indicated by variant group 22.56％ (143/634)and contrast group 18.30％ (295/1 612); but crippled in PCA-P1 formation (x2=4.32,P＜0.05)which illustrated by proportions of by dysplasia and deficiency compared by variant group and contrast group was 17.35 ％ (110/634),14.21％ (229/1 612).AC A-A 1 normal,slight variation,dysplasia and deficiency together with FTP dyformation was 9.15％ (58/634),15.62％ (52/333),16.50％ (34/206),23.16％ (22/95) respectively.Within the variation group,a pattern between ACA-A1 and FTP which fluctuated simultaneously with significant statistical discrepancies (x2=51.117,P＜0.01; linear by linear x2=13.340,P＜0.01)which demonstrated by ACA-A1 normal,slight variation,dysplasia,deficiency together with FTP formation was 4.57％ (29/634),12.91％ (43/333),16.02％ (33/206),20.00％ (19/95) respectively,as far as ACA-A1 variation was concerned,The variant group were more prone to develop PCA-P1 dysplasia or deficiency (x2=45.87,P＜0.01; linear-by-linear x2=43.474,P＜0.01).Conclusions There were more multi-variation of Willis' circle in the cases with ACA-A1 variation,MRA can value the anatomy and variation of the Willis' circle.MRA can also guide the clinic diagnosis,treatment and prognosis of the cerebrovascular diseases.

Objective (1)To observe the imaging features of the normal anatomic structures of middle ear using CT virtual endoscopy.(2)To study morphologic changes of ear ossicles and auditory ossicular chain of patients with conductive deafness.Methods CTVE of the auditory ossicular chain was performed on GE Hispeed CT/I with 1.0 mm slice thickness at pitch 1, bone algorithm, voltage 140 kV, electric current 170～220 mA, 9.6 cm field of view.Results CTVE could clearly demonstrate the normal auditory ossicular chain and its anatomic details. The demonstration rate of CTVE images in detecting the malleus-incus joint was 100%(162/162), in detecting "L"type incus-stapes joint was 80%(130/162), in detecting the anterior and posterior stapes footplate was 73%(121/162); CTVE could well display the destruction of auditory ossicular chain in otitis media and cholesteatoma and could acurately show the malformation of the auditory ossicular chain.Conclusion CTVE can quickly, non-invasively, three-dimensionally display the middle ear auditory ossicular chain, can provide direct and reliable imaging information for discovering the cause of a disease of conductive deafness.

Objective To study the value of CT virtual endoscopy(CTVE) and multiplanar reconstruction(MPR) in the diagnosis of small intestinal diseases.Methods The small intestines in 13 cases with small intestinal lesions were filled with enough air by means of gastro-duodenal tube,after CT volume scans of the small intestine with multi-detector row CT scanner,VE and MPR were reconstructed and analyzed retrospectively.Results 91%(10/11) of the space-occupying lesions of small intestine were found by VE,among them,100%(8/8) of tumors inside the lumen and 66.7%(2/3) of tumors outside the lumen were diagnosed.82%(9/11) of the space-occupying lesions of small intestine were found by MPR.100%(11/11) of the space-occupying lesions of small intestine were found by VE combined with MPR.2 cases with small intestinal inflammatory lesions were also well showed by CTVE and MPR.Conclusion CTVE and MPR are of significant clinical applied value in diagnosing the small intestinal diseases.