BACKGROUND:The carotid siphon has a complex structure, which is difficult for two-dimensional imaging observation due to shelter from the basicranial bone. Digital subtraction angiography is conducive to display the course of carotid siphon, but there is a lack of anatomical landmarks. Three-dimensional CT imaging is beneficial to show the structure of carotid siphon and have its measurement, which provides a new and effective means in relevant studies.
OBJECTIVE:To clarify the morphology and calcification distribution of the carotid siphon, thereby providing an objective basis for relevant clinical and basic research.
METHODS: A total of 206 patients, over 50 years old, with no lesions or variation under head and neck CT angiography were selected and divided into non-calcification group (n=70) and calcification group (n=136). The carotid siphon was reconstructed on the imaging workstation to observe the classification (“U”, “V”, “C” and “S” types) and calcification distribution, the bending angles of C4 and C5 segments as wel as lumen diameter were measured.
RESULTS AND CONCLUSION:The 70 patients in the non-calcification group were at a mean age of (59.17±10.27) years, and the “U” type accounted for 35.7%, “V” type for 30.7%, “C” type for 27.2%, and “S” type for 6.4%; Among them, 33.3% patients (25/70) had the same type at both sides; the lumen diameter was (4.92±0.63) mm, and the blending angles of C4 and C5 were (87.23±16.66)° and (49.21±16.01)°. In the calcification group, the mean age was (67.39±9.32) years, and there were 41.5% of “U” type, 33.1% of “V” type, 24.3% of “C” type, 1.1% of 24.3%, and among the 136 patients, 43.4% (59/136) showed the same type at both sides; the lumen diameter was (4.90±0.44) mm, and the blending angles of C4 and C5 segments were (84.44±17.20)° and (52.57±14.16)°. There were significant differences in age and “S” type between the two groups (P < 0.05), but no statistical difference in the lumen diameter and blending angles of C4 and C5 (P > 0.05). In the calcification group, the calcification percentage of inwardly and outwardly curved regions was 13.60% and 19.01% for C4, 27.34% and 16.52% for C5, 9.94% and 13.60% for C6. The morphology of the carotid siphon is mostly seen as “U”, “V”, “C” types, and over 50% types are different at both sides. Calcification of the lumen wal is seen most in the inwardly curved region of C5 segment, folowed by the outwardly curved region of C4 segment. The incidence of calcification is increased with age, which is lower in the S-type carotid siphon. The lumen diameter and blending angle of the carotid siphon show no correlation with calcifications.

BACKGROUND: Clinical diagnosis criteria for rotary subluxation of atlanto-axial joint have not been identified. Many clinical diagnoses are suspicious. Therefore, investigating a new diagnostic method and diagnostic evidence is beneficial to enhancing diagnosis accuracy, and is a study hotspot in the current field.OBJECTIVE: This study aimed to observe the relationship between anatomy of normal human atlanto-axial joint and functional positions, and to provide anatomical basis for the diagnosis of atlanto-axial rotary subluxation.DESIGN: Single sample self-control study.SETTING: Department of Imageology, Zhongshan Hospital Affiliated to Xiamen University.PARTICIPANTS: This study was carried out in the CT Room, Department of Imageology, Zhongshan Hospital Affiliated to Xiamen University between June 2003 and November 2004. Fifty-three volunteers, 27 males and 26 females, with an average age of 31.2 years (range 4.5-75 years), without cervical trauma or history of cervical diseases, were randomly recruited in to this study. Written informed consents were obtained from each subject or their guardians.METHODS:CT helical scanning and three-dimensional reconstruction imaging of atlanto-axial joint in the neutral position were performed in all the volunteers and were supplemented in the right and left rotary position in 21 subjects on a helical CT scanner (somatom plus 4, Siemens, Germany), SUN magic view 1000 workstation and three-dimensional reconstruction software.MAIN OUTCOME MEASURES: ① Lateral atlanto-axial articular facet contraposition. ② Lateral atlanto dental space③ Atlanto dental interval. ④ The largest extent of articular facets dislocation in the right and left rotary positions. ⑤ Head's rotary maximal angle in the right and left rotary positions.RESULTS: ① Three-dimensional images with atlanto-axial joint in the functional position of 53 patients showed that the articular surfaces of lateral atlanto-axial joint had basic contraposition, the width of atlanto-dental interval ranged from 1.0 to 3.3 mm, and the lateral atlanto-dental distance devirated in 24 patients (45.28%).②Three-dimensional images with atlanto-axial joint in the rotary position of 21 patients showed that the width of atlanto dental interval had no change, the articular facets of lateral atlanto-axial joint had rotary displacement with the width ranging from 5.76 to 8.18 mm, and anastomotic area of articular facet was decreased by 1/2 to 2/3. The condyles had deflected to the rotary direction in the patients with symmetrical lateral atlanto dental space, and for 15 patients with asymmetrical lateral atlanto dental space, the condyle deflected slightly or had no changes.CONCLUSION: CT-three dimensional imaging can clearly show the anatomical structure of atlanto-axial joint in functional position and the changing rule of atlanto-axial joint movement, providing theoretical evidence for the clinical diagnosis and the treatment of atlanto-axial subluxation.

Objective To evaluate the clinical value of CT three-dimensional(3-D) imaging on diagnosing of bone and joint diseases.Methods The imaging findings of 357 cases proved by operation or clinic were analyzed retrospectively by the 3-D imaging.The diagnosis accuracy of 3-D imaging was compared with that of routine CT.3-D images were obtained by surface shade display(SSD),multi-planar reconstruction(MPR),maximum intensity project(MIP) and volume rendering(VR).Results In 357 patients,257 cases were traumatic disease,100 cases were non-traumatic disease.The diagnosis accuracy of 3-D imaging was 98.3%,which was higher than that of routine CT(P

ObjectiveTo valuate the three-dimensional CT angiography(3DCTA) in diagnosing blood vessel diseases.MethodsCTA findings of 284 patients confirmed with blood vessel diseases were retrospectively analyzed.They were divided into two groups:141 cases of head and neck and 143 cases of trunk and extremities.Scan was performed with the beam collimation of 0.625 ～ 3.0mm,increment of 0.3 ～ 1.4mm,pitch of 1.0 ～ 1.5,with the gross contrast medium of 1.5 ～ 2.0ml/kg.3D imaging methods included volume rendering(VR),multi-planar reformatting (MPR),curved planar reformatting(CPR),surface shade display(SSD),maximum intensity project(MIP) and virtual endoscopy(VE).The diagnostic results of CTA were compared with those of DSA and/or surgery.ResultsIn this study,3D images of vasculature met the diagnostic criterion.The diagnostic sensitivity,specificity and accuracy of CTA was 97.28％,82.35％ and 96.48％,respectively.The size of artery aneurysm shown with CTA and DSA had no significant difference( P ＞0.05 ),both smaller than that in surgery( P ＜ 0.05 ).Conclusion3DCTA could be used in diagnosing the cardiovascular diseases and compensate the limitation of conventional CT.It had the characteristics of non-invasion,high accuracy and could partly substitute DSA.

BACKGROUND:The hemodynamics changes of aneurysm provide the basis for aneurysm treatment and ruptured aneurysm prevention, while finite element analysis is a good technical means.
OBJECTIVE:To construct the two-way flow-solid coupling model of internal carotid artery aneurysm, and thus simulate its flows.
METHODS:CT angiography data of internal carotid artery aneurysm were recorded with GE Lightspeed 64 spiral CT scanning, and the corresponding three-dimension model was constructed with mimics10.01 software. Then the fluid-solid coupled flow simulations were done depending on Ansys+Fluent software.
RESULTS AND CONCLUSION:The two-way flow-solid coupling model of internal carotid artery aneurysm was built, with the same morphology and anatomy as the three-dimensional CT imaging. In the whole cardiac cycle, the blood flow of aneurysm body was swirl typed and its velocity was slower than that of the aneurysm neck;the deformation, wal shear stress, pressure and von Mises stress of aneurysm wal were the maximum at the neck, and the minimum at the top. Their highest value was at the 0.16 s (rapid ejection period), and their lowest value at the 0.74 s (relaxation period). On the basis of CT angiography data, to construct the two-way flow-solid coupling model of internal carotid artery aneurysm is a simple and practical method. The blood flow simulation of aneurysm is close to the human physiological conditions, and the results wil provide new theoretical basis for the study on the occurrence and development of aneurysm.

Objective To evaluate the techniques of separating, fusing, opacifying and falsecoloring- volume rendering( SFOF-VR)3D imaging on the bone and blood vessels in the region of atlantoaxial joint(AAJ). Methods SFOF-VR 3D imaging was performed on 35 cases, including normal (n = 6),variations and lesions( n =29), which were selected from cases with the head-neck CTA examination. With the original scanning data, the VR imaging was performed, then SFOF-VR imaging. Comparisons were made between the features of 3D images of SFOF-VR and VR in showing the anatomy, diagnosing the variation and lesion of AAJ and VA, and the results were analyzed by using the Fisher exact test. Results The results of 35 cases included 6 normal cases in the region of atlantoaxial joint and VA, 16 variations in atlantoaxial joint or VA, 6 cases with arteriosclerosis in VA and 7 cases with fracture or dislocation of atlantoaxial joint. All SFOF-VR imaging are satisfactory. SFOF-VR imaging can show the atlas, epistropheus and VA independently or jointly, cut or color the structures freely and get 3D measurements in any direction.Comparisons showed that SFOF-VR images were much clearer and more comprehensive than VR in displaying the anatomy, variation and lesions of AAJ and VA. Statistical differences were found in showing the spatial structure, blocking structure, space measurement, variation and disease and image edge ( there are25,7,3,0, 31,3,1,0, 26,3,6,0, 23,7,5,0, 0,10,20,5 cases for SFOF-VR image with excellent,good, ordinary and poor quality, and 2,5,24,4, 0,2,8,25, 0,7,25,3, 5,6,23,1, 29,4,2,0 cases for VR;χ2 values 40. 259, 61.444, 42.245, 24.220, 51.299, P<0. 01 ). Conclusions SFOF-VR is a new 3D imaging technique which can clearly and directly show the bones and blood vessels in the region of AAJ.It can provide anatomical information for imaging diagnosis and surgical operation.

BACKGROUND:The siphon of internal carotid artery is a complex of bending and surrounding structure, which has become a research hot in the field of medical imaging and regional anatomy. There is little research on the hemodynamics of internal carotid artery. Finite element analysis provides the basis for the related dynamics research. OBJECTIVE:To explicit the hemodynamic characteristics of the normal and stenosis internal carotid artery, and to explore the relevant influential factors. METHODS:Finite element model of the siphon of internal carotid artery was built based on 64-slice spiral CT data, and then, three-dimensional models were constructed using Mimics 10.01 software. There were simulations of the normal and post-stenosis blood flows with ANSYS 13.0 CFX software, to observe the changes of hemodynamics, and to analyze their characteristics and differences. RESULTS AND CONCLUSION:The normal blood flow at the siphon of internal carotid artery was in a laminar state, but rotation and turbulent flow formed at the two angle regions. The velocity of external bending zone was slower than that of the internal. The slower was the velocity, the more obvious was the turbulence. The wal shear force decreased at the angle regions, and the wal shear force of external bending zone was smal er than that of the internal. At the region of arterial stenosis, the blood flow was sped, and at the downstream, turbulent flow and low zone of wal shear force were formed. With the increase of stenosis severity, the turbulent flow and low wal shear force area were expanded. Central stenosis showed more obvious effects than the eccentric one. The degree of stenosis and bending at the siphon of internal carotid artery can directly influence the formation of turbulent flow and low wal shear force area, which are more obvious at the external bending zone and central stenosis.

Objective To assess apoptosis mediated by the cell death receptor Fas in peripheral T lymphocytes of patients with abdominal aortic aneurysm. Methods The apoptotic pathway was triggered by anti-Fas monoclonal antibody in cultured and activated peripheral T-cells from 20 AAA patients. Control groups consisted of 15 patients with aortic atherosclerotic occlusive disease(AOD)and 25 healthy individuals. Cell survival and death rate were assessed. Results Cross-linkage of Fas receptor exerted a strong apoptotic response on T cells from AOD patients and healthy controls, while the effect on T cells was very limited from that of AAA patients. The evaluation of cell Survival rate showed a significantly higher percentage in AAA group(98.9%±10.3%)than in the AOD subjects(58.9%±15.2%)or the healthy group(59.4%±12.9%;P＜0.001＝.Apoptosis assessment by annexin V and propidium iodide staining and flow cytometry showed similar results. The defect in AAA group was not due to decreased fas expressed at normal levels. Moreover,it specifically involved the Fas system because cell death was induced in the normal way by methylprednisolone. Conclusions Fas-induced apoptosis in activated T cell from AAA patients is impaired. This may disturb the normal down-regulation of the immune response and thus provide a new insight into possible mechanisms and routes in the pathogenesis of AAA.

Objective:To establish and verify the prediction model of benign or malignant of solitary pulmonary nodules (SPNs≤20 mm) based on artificial intelligence.Methods:Totally 338 SPNs (≤20 mm) from 279 patients, confirmed by operation and pathology, were selected in Zhongshan Hospital Xiamen University from November 2018 to May 2020. Clinical data (age, gender, smoking history, individual and family history of malignancy), image features (maximum diameter, minimum diameter, solid proportion, volume, lobulation sign, burr sign, vacuole sign, cavity sign, pleural indentation sign, and radiomic features (maximum CT value, minimum CT value, average CT value, median CT value, CT value standard deviation, skewness, peak, energy, entropy) were analyzed retrospectively. All the data of patients were randomly divided into training set (271 SPNs) and test set (67 SPNs). In the training set, the clinical, image features and radiomic features were first selected by the least absolute shrinkage and selection operator (LASSO) regression, then the independent risk factors of SPN (≤20 mm) were screened out by multi-variate logistic regression analysis, and the nomogram prediction models were constructed. Finally, the data of test set were used to verify the prediction model by the ROC curve and calibration curve (CC).Results:In the training set of 271 SPNs, 81 SPNs were benign and 190 malignant. After analysis of LASSO regression and multi-factor logistics regression, the independent predictors of benign or malignant SPN were age, gender, largest diameter, vacuole sign and solid proportion. The prediction model was P=e x/(1+e x), x=-2.583+0.027×age+1.519×gender+0.127×maximum diameter-2.132×solid proportion+1.720×vacuole sign. The results of the model showed that the area under curve (AUC) of ROC was 0.850, and the sensitivity was 73.7%, specificity was 82.7% and accuracy was 82.3%. In the test set of 67 SPNs, 22 SPNs were benign and 45 malignant. The results showed that the AUC of ROC was 0.882, and the sensitivity was 82.2%, specificity was 81.8% and accuracy was 85.1%. The calibration nomogram of prediction model showed that CC from training set or test set well coincided with its individual ideal curve ( Ptraining=0.688, Ptest=0.618). Conclusion:Prediction model of benign or malignant SPN ≤20 mm is established based on AI; it can obtain the prediction probability and has good diagnostic efficiency.

BACKGROUNDMagnetic resonance imaging (MRI) has advantages in showing pathologic changes of disc space infection, which is important in clinical treatment. The purpose of this study was to describe the MRI findings of disc space infections in relation to chronicity.

METHODSMRI of 60 patients from January 1, 2002 to April 30, 2012 in Ottawa Hospital were retrospectively evaluated by two radiologists blindly. All patients had histological confirmation, with 55 having microbiological confirmation as well. These patients were divided into acute (n = 18), subacute (n = 21) and chronic (n = 21) based on histological findings. The following potential signs of MRI finding were assessed: marrow edema, endplate erosions, disk fluid and height change, paraspinal mass, epidural collection, facet fluid and enhancement in the marrow, disc, paraspinal mass, and epidural involvement. Statistical analysis consisted of t- or F-tests and chi-square test.

RESULTSIn the 60 patients, 83 infected discs (single disc in 45 patients, 2-4 discs in 15 patients) were found, including 22 discs in the acute group, 30 discs in the subacute group, and 31 discs in the chronic group. There was a significant difference in the extent of marrow edema between the acute, subacute and chronic groups (P < 0.05), with a gradually increasing extent from acute to chronic. The extent of endplate erosions increased with chronicity, but was not statistically significant. There were significant differences in the disc fluid, epidural collection, and disc enhancement among the acute, subacute and chronic groups, as well as the facet fluid between acute and chronic groups (P < 0.05). There were no significant differences in the present probability of disc height loss, paraspinal mass, and marrow enhancement among the three groups (P > 0.05).

CONCLUSIONSFrom acute to chronic infections, the extent of marrow edema and endplate erosions appeared to gradually increase. Epidural collections and facet fluid are most frequently found in the acute group, while disc fluid and disc enhancement are more common in the chronic patients.

Adult ; Aged ; Aged, 80 and over ; Discitis ; diagnosis ; Female ; Humans ; Magnetic Resonance Imaging ; methods ; Male ; Middle Aged ; Retrospective Studies