Résumé
Objective To evaluate the value of 64-slice spiral CT angiography based on pre- contrasted raw data in diagnosing pulmonary arteriovenous fistula.Methods 64-slice spiral CT plain scan and enhanced scan was performed in 16 patients with pulmonary arteriovenous fistula,pulmonary angiography based on pre-contrast and post-contrast raw data was performed respectively,including maximum intensity projection(MIP),shaded-surface display(SSD),and volume rendering(VR).According to the results of angiocardiography and surgical findings,comparson of the three methods was made in the display of PAVF in pre-contrast and post-contrast phase images.Results 8 of the 16 PAVF cases were single lesion,8 cases were multi-lesions.30 PAVF lesions were found in all the patients.MIP,SSD and VR based on pre-contrast raw data displayed PAVF lesions in 20,14,and 22,respectively.The combination of the 3 methods based on pre-contrast raw data could show 26 PAVF lesions.MIP,SSD,and VR based on post-contrast raw data displayed PAVF lesions in 24,18,and 30,respectively.The combination of the 3 methods based on post- contrast raw data could show 30 PAVF lesions.Conclusion 64-slice spiral CT angiography based on pre- contrasted raw data can clearly show the position,number,and shape of PAVF lesions,which is of great value in diagnosing PAVF.
Résumé
Objective To observe the CT findings of hypoplasia of cochlear nerve foramen. Methods CT findings of cochlear nerve foramen were observed in 50 volunteers (100 ears)and in 9 cases with hypoplasia of cochlear nerve foramen.The width of the bony canal for the cochlear nerve were measured in both groups.Results The fissure in the cribriform area were seen in every volunteers.The width of the bony canal for the cochlear nerve was (2.32?0.25)mm in normal group.The stenosis of cochlear nerve foramen were shown in 9 cases (10 ears),the lacking of fissure in the cribriform area were seen in 8 ears, while the fissure were shown in 2 cases.The stenosis of internal auditory canal was shown in 4 cases. Abnormality of vestibule and horizontal semicircular canal was shown in one case.The maximum value of the width of the bony canal for the cochlear nerve was 1.5mm,the minimum value was 0.9 mm.Conclusions The typical CT findings of hypoplasia of cochlear nerve foramen were stenosis of cochlear nerve foramen,the lacking of fissure in the cribriform area and cochlear nerve foramen without helix shape.The hypoplasia of cochlear nerve foramen may be a subtype of cochlear dysplasia.