ABSTRACT
Objective To investigate the clinical value of 2 dimension late Gadolinium enhancement MRI (LGE-MRI) technique for the evaluation of atrial myocardial fibrosis in patients with atrial fibrillation. Methods Forty-nine cases of atrial fibrillation in our hospital from March 2015 to December 2016 were retrospectively collected. The LGE-MR was acquired by the Siemens 3.0 T MR machine before the catheter ablation.The findings of LGE-MR were evaluated by two experienced doctors. The left atrium(LA)were manually segmented into 8 regions in axial view.All patients were classified into 4 stages based on the extent of enhancement, stage 0: absence of enhancement, stage Ⅰ: enhancement appeared in minimal two consecutive slices in single region,stageⅡ:enhancement in two regions,stageⅢ:enhancement in three or more regions. All electroanatomic maps were obtained after electrical conversion during catheter ablation. The Kappa test was used to assess the consistency of LGE-MRI left atrial myocardial fibrosis and CARTO system of the left atrial endocardial voltage reconstruction. Results Forty-nine cases of atrial fibrillation with LGE-MRI and CARTO were included. There were 17 cases of atrial fibrosis stage 0,10 cases of stageⅠ,11 cases of stageⅡ,11 cases of stageⅢaccording to LGE-MRI findings;There were 17 cases of atrial fibrosis stage 0,19 cases of stageⅠ,12 cases of stageⅡ,11 cases of stage Ⅲ with reference to CARTO findings. The diagnostic accuracy of the LGE-MRI atrial fibrosis was 81.6%(40/49),of which the correlation was good(Kappa= 0.751,P<0.001). Conclusions LGE-MRI can accurately assess the degree of left atrial myocardial fibrosis in patients with atrial fibrillation,help to select the proper candidate and strategy in catheter ablation.
ABSTRACT
Objective To study the variability of the parameters of the pedicle screw path and influencing factors of clinical significance. Methods A Picker PQ6000 Spiral CT was used to scan 736 vertebrae from C 3 to L 5 of 118 men and 80 women aged between 17 and 58. The largest transverse diameter, screw path length and e angle (the angle between the axis of the pedicle and sagittal plane) of each pedicle were measured. The contour of the vertebrae and the relationship of the sagittal axis of the spinal process, vertebral body and human body were inspected. Any discrepancy of these axes was measured and recorded. The gender, age, height and weight were recorded at the same time. Results Measurement of the biggest transverse diameter, screw path length and e angle at each vertebral level showed a wide range of value and quantity. Although the screw path length and the transverse diameter of the pedicle showed significant difference between man and woman, further covariance analysis for between subject effects revealed that no inter gender difference existed after the effects of height and weight were removed. Both height and weight showed significant positive correlation with the screw path length and transverse diameter of the pedicle, but no correlation with the e angle. Observation on the deformity of the vertebrae showed that the sagittal axes of the vertebral body and human body was discrepant in 14 thoracic and lumbar vertebrae; the sagittal axes of the spinal process and vertebrae was discrepant in 11 vertebrae; the transverse diameter of the pedicle was smaller than 4 mm in 14 vertebrae below T 9; 4 vertebrae showed lateral convex pedicle. Conclusion The parameters of the pedicle screw path varied in different subjects and different vertebral level with a large variability. The weight and height are two important factors to influence the parameters. Deformity is another factor which may lead to mistake of placement of the pedicle screw. To improve the accuracy of the pedicle screw, individual identification of the entering point and orientation should be considered and in some circumstances even special screws, should be used.
ABSTRACT
Objective To evaluate tumor angiogenesis and clinical significance by contrast-enhanced CT in case of non-small cell lung cancer (NSCLC). Methods 30 patients with NSCLC underwent dynamic thoracic CT, and histopathological slides were carefully prepared for VEGF immunohistochemical staining. Maxium attenuations of dynamic CT were compared with VEGF expression levels and lymph-node metastases. Results The mean peak attentation was (36.28?6.41)HU, VEGF positive expressions were in 21 patients, and negative expressions were in 9 patients. VEGF expression levels in patients with NSCLC stage II and III were higher than those in stage I , and in lymph node metastases group, the expression levels of VEGF were also higher than those in non-metastatic nodes. CT enhancement of NSCLC was positively related to VEGF expression,neoplasm stage and lymph-node metastases. Conclusion CT enhancement of NSCLC can reflect tumor angiogenesis and correlate to lymph-node metastases closely, help lung cancer diagnoses,neoplasm stage, and serve as a supplement to the present staging system for lung cancer in biological behavior.