Comprehensive Imaging Study Of The Malformation Of The Cranial Cervical Junction

Part One Imaging Evaluation of the Malformation of the Cranial Cervical JunctionBackground and Purpose:The malformation in the region of South and East Asia countries is relatively high incidence of craniocervical junction(CCJ), especially in China and India. It is a kind of disease which covers the pathological changes in this region of the bone structure and nervous system. The imaging evaluation of major malformations of craniocervical junction, to understand the causes, types and pathologic abnormalities of the imaging characteristics, further deepen our understanding of craniovertebral junction abnormalities, improve the level of diagnosis, and guiding clinical examination and treatment of a reasonable case.Materials and Methods:Collecting 266 cases of patients with cervical junction malformation in our hospital, which were confirmed by imaging and clinical from september 2011 to march 2016.All patients had the lateral position,the mouth opening position, and the flexion and extension DR image. multilayer CT images and MRI images of the cranial cervical junction. CTA of the vertebral artery were performed in 56 patients with the cervical region of the atlas and occipital fusion. Two deputy director of physicians engaged in the head and neck imaging diagnosis for many years, readed and recorded the results of imaging diagnosis from the PACS, respectively. Who did not know the premise of the clinical manifestations. Main observation index: the position of the dens, the angle of the base of the skull, atlantodental interval(ADI),space available for the spine cord(SAC), the angle of the cervico-medullary angle(CMA) and the spinal cord. Using SPSS17.0 statistical software for statistical processing, counting data between the use of T test, measurement data comparison using chisquare test, consistency analysis using kappa test. Correlation analysis using spearman correlation test.Results:1 Chiari malformation was found in I type in 192 cases(182/266), type II in 33cases(33/266), The detection rate in tape I of MRI was higher than CT, and the difference was statistically significant(P<0.05). There was no significant difference in the detection rate of tape II(P>0.05); 247 cases(247/266) of basilar impression were found, and 56 cases(56/266) of flat skull base were found, and 156 cases(156/266)of vertebral segmentation anomaly were found.The detection rate of three kinds of examination methods in basilar impression, flat skull base and vertebral body the segmentation anomaly is not statistically significant(P>0.05). 33 cases(33/266) of the dentate process were found, contrast the detection rate of three kinds of inspection methods, CT and had statistical significance in the detection rate of DR(P<0.05), CT is better than DR,but there was no significant difference in the detection rate of CT and MRI in the dentate process(P>0.05); 92 cases of dislocation of atlas and axis were diagnosed, the detection of the dislocation of the joint dislocation, CT better than DR and MRI, the difference was statistically significant(P>0.05).2 In the measurement of the degree of the protrusion of the teeth, the distance between the axis and the axis, and the skull base angle. The difference between DR and CT was not statistically significant(P>0.05), and the two methods were in good agreement. The results in odontoid process and ADI measured by MRI were good than DR and CT, the difference was statistically significant(P<0.05); differences on the results of the angle of the base of the skull and SAC measured by CT and DR was not statistically significant(P<0.05).3 Lateral atlantoaxial articulation was classified according to the CT sagittal lateral atlantoaxial joint and the articular surface of the tilt direction of the slip.Normal type(N type) 179 side joint; the I tape has 135 side joint; the II tape has 75 side, the ? type has 54 side, the IV type has 86 side joint. When the lateral atlanto occipital fusion of atlantoaxial joint morphology anomalies more obvious, type II and type III a higher proportion, however, N type, I type and IV type were higher in other malformations.4 According to the relationship between vertebral artery and the transverse process of the atlas and the lateral mass and the posterior arch on CT images, 56 cases of the vertebral artery in cases were divided into four types: normal type 28(25%);type I 36(32.1%); type 23(20.5%); type III 25(22.4%), the difference was statistically significant(P>0.05).5 CMA and brain stem spinal cord were measured on the MRI images in all cases in this group. The measurement range of the cervical spinal cord angle was117.7o-167.0o, average 133.7o. The measurement range of the brainstem spinal cord angle was 125.7o-161.0o, with an average of 138.7o. The scope of the cerebellum under the amygdala 5mm-14.6mm., with an average 7.2mm. CMA and brainstem spinal cord angle measurements were in good agreement(P>0.05). In the group with or without syringomyelia, there was significant difference between CMA and brainstem spinal cord angle and the degree of the herniation of the cerebellum(P<0.05).6 A statistical analysis was made on the instability of the joint with syringomyelia(P<0.05). It was found that there was a correlation between the instability of the joint and the cavity of the spinal cord.Conclusions:1 CT examination showed a unique advantage in the display of bony anomalies in the cranial cervical region. It can estimate the stability of atlantoaxial joint through the depiction of atlantoaxial lateral joint morphology.2 CTA can provide accurate data for the operation of the cranial cervical junction malformation and provide accurate data for the location of the vertebral artery. It can provide reliable guarantee for the safety of the operation of the patients.3 MRI images can be used for the measurement of all kinds of radial neck deformity patients, brainstem spinal cord angle and CMA can be used to assess the pressure of the cervical cord and medulla, CMA measurement is more convenient.4 The degree of herniation of the lower part of the cerebellum and the stability of the axial joint were correlated with the cavity of the spinal cord. The more obvious the more obvious, the more prone to the emergence of the syringomyelia, the possibility of the emergence of the syringomyelia was increased when the instability occurred.Part Two Application of new imaging methods in evaluating the stability of the malformation of the Cranial Cervical JunctionBackground and Purpose:At present, most of the imaging studies focus on the analysis and summary of the abnormal structure of the CCJ. The observation and study of the movement function and stability of the region are rarely seen, the stability of the CCJ region has important guiding significance for the selection of treatment methods. In this paper,the stability of the CCJ was studied by using the new X-ray technique(dynamic photography and digital tomosynthesis), and compared with CT scan, in order to find a more convenient and accurate imaging method to observe the stability of the CCJ.Materials and Methods:Collecting 114 cases of patients with atlanto-occipital fusion malformation in our hospital, which were confirmed by imaging and clinical from september 2012 to march 2016.All patients had the dynamic position DR, cervical spine dynamic photography, flexion and extension digital tomosynthesis and conventional horizontal CT scan. CT scan of flexion and extension of the CCJ were performed in 32 patients.Two deputy director of physicians engaged in the head and neck imaging diagnosis for many years, readed and recorded the results of imaging diagnosis from the PACS,respectively. The main diagnosis is the atlantoaxial joint dislocation and its stability,while the lateral atlantoaxial articulation form type. SPSS17.0 statistical software was used for statistical processing, the count data were compared using T test, consistency analysis using kappa test.Results:1 48 cases of dislocation and 26 cases of instability of the atlantoaxial joint were diagnosed by dynamic position DR; 44 cases of dislocation and 30 cases of instability of the Atlantoaxial joint were diagnosed by cervical spine dynamic photography;67cases of dislocation and 44 cases of instability of the atlantoaxial joint were diagnosed by flexion and extension digital tomosynthesis. There was statistical significance in the difference of the diagnostic efficiency between the tomosynthesis and the dynamic photography and DR, the diagnostic efficacy of tomosynthesis was higher than that of dynamic position DR and cervical spine dynamic photography(P<0.05). The difference of the diagnostic efficacy between dynamic position DR and cervical spine dynamic photography was not statistically significant(P>0.05).2. 10 type N, 43 type I, 83 type II, 54 Type III and 38 type IV were diagnosed by CT; 14 type N, 39 type I, 89 type II, 49 type III and 37 type IV were diagnosed by tomosynthesis photography. Statistically significant differences in the two kinds of imaging methods for type III of lateral atlantoaxial articulation(P<0.05), the accuracy of CT is better than that of tomosynthesis. In the classification of N, I type, II type and IV type, the difference between the two methods is not statistically significant(P>0.05).3.17 cases of instability of the atlantoaxial joint were diagnosed by CT scan with dynamic position; 25 cases of instability of the atlantoaxial joint were diagnosed by tomosynthesis. The difference between the two methods is statistically significant(P<0.05).4.Type I with atlantoaxial dislocation were 17 cases, type II with atlantoaxial dislocation were 31 cases, type III with atlantoaxial dislocation were 25 cases, there was no atlantoaxial dislocation in type N and type IV. The atlantoaxial instability was often found in type II and type III.Conclusions:1. The diagnostic ability in finding atlantoaxial stability of flexion and extension tomosynthesis photography is better than dynamic position DR and cervical spine dynamic photography.2. The accuracy of the classification of the lateral atlantoaxial articulation with atlanto-occipital fusion by tomosynthesis is comparable with that of the CT, it can also be observed at different positions, and should be used as the first choice to predict the stability of the axial joint.3. Compared with supine flexion and extension CT scan, vertical flexion and extension tomosynthesis can be more realistic and accurate in response to the stability of the axial joint.