Objective:To improve the CT and MRI diagnostic accuracy of intracranial atypical cavernous angiomas(ACA).Methods:We retrospectively analyzed CT and MRI appearances,operative and pathological findings of 12 cases with ACA.Of them,11 cases were seanned by CT,10 cases by MRI and 9 by both CT and MRI.Results:Of 12 cases:One case as located at the sella ,1 case was at the fourth ventricle,5 cases were located at the cerebral hemisphere,4 cases were located at the middle cranial fossa and 1 case was at the posterior cranial fossa.There was edema in 3 cases,1 case had cystic component and 4 cases had cerebral hemorrhage.The localized rate of ACA by CT and MRI was 100%,but 11 cases were misdiagnosis and 1 case did not made the qualitative diagnosis. Conclusion:The qualitative diagnosis of ACA have some difficulty,so that the emphasis should be on the analysis of the combination imagiology and clinic.

Objective To evaluate the clinical application of helical CT 3D reconstruction technique in the dental orthopaedics. Methods The helical CT was performed with 3.0 mm slice thickness and 1.0 pitch in 41 patients with dental orthopaedics. The 3D reconstructions, including maximum intensity projection (MIP), surface shaded display (SSD), and multiplanar reconstructions (MPR), were made for all the cases. Results Thirty-seven of the 41 patients showed malalignment, tilt, rotation, overlap of the teeth and the different space between the longitudinal axes of the teeth. Twenty-five cases of them have shown 36 buried teeth in all. The axial images covered all the information. SSD demonstrated the external contours and entire morphologies of the teeth and the mandible with the relationship of the teeth alignment and the mandible. MIP clearly manifested the full view and the longitudinal alignment of the teeth. Among the 36 buried teeth, there were 29 palatally and 7 labially presented teeth, and they were morphologically delineated on MIP through various angles. Conclusion The helical CT 3D reconstruction is a new technique to display the stereoscopic configuration of teeth. The combination of axial images and MIP, SSD, and MPR provides valuable anatomic and diagnostic information helpful for the surgeons to structure and determine the treatment protocol for the dental orthopaedics.

Objective To explore the diagnostic consistency and correlation between MR discography (MRD) and CT discography (CTD) in diagnosing chronic low back pain. Methods Guided by C - arm fluoroscopy the mixed solution of gadoterate meglumine (GD-DOTA) and Iohexol (GD-DOTA at a dilution of 1 ∶ 400 with Iohexol) was injected into 96 lumbar intervertebral discs of the 36 patients. CT scanning was performed at 15 minutes after the injection of contrast, and axial together with sagittal SE T1WI MR scanning was carried out one hour after the injection. CTD and MRD images were randomly numbered and were independently evaluated by two experienced radiologists according to Dallas discogram scale in order to assess the diagnostic consistency and correlation between (MRD) and (CTD). In addition the diagnostic value of MRD was evaluated. Results The results revealed that in determining disc degeneration grade CTD and MRD were highly consistent with each other(Kappa = 0.836, P < 0.01), and the diagnostic results judged by the two reviewers were essentially in agreement (ICC = 1.00, P < 0.01; r = 0.997, P < 0.01). Higher consistency (Kappa = 0.836, P < 0.01) and correlation(ICC = 0.90, P < 0.01; r = 0.869, P < 0.01; Kappa =0.836, P < 0.01) in determining annulus rupture extent were also obtained. Conclusion MRD is an accurate diagnostic method for the determination of disc degeneration and the severity of annulus rupture, and this technique has greater consistency and correlation with CTD in diagnosing chronic low back pain.