Anatomical correlation between left atrium pulmonary vein ablation targets of atrial fibrillation and adjacent bronchi and pulmonary arteries by MSCT.

BACKGROUND: The ablation targets of atrial fibrillation (AF) are adjacent to bronchi and pulmonary arteries (PAs). We used computed tomography (CT) to evaluate the anatomical correlation between left atrium (LA)-pulmonary vein (PV) and adjacent structures. METHODS: Data were collected from 126 consecutive patients using coronary artery CT angiography. The LA roof was divided into three layers and nine points. The minimal spatial distances from the nine points and four PV orifices to the adjacent bronchi and PAs were measured. The distances from the PV orifices to the nearest contact points of the PVs, bronchi, and PAs were measured. RESULTS: The anterior points of the LA roof were farther to the bronchi than the middle or posterior points. The distances from the nine points to the PAs were shorter than those to the bronchi (5.19 ± 3.33 mm vs 8.62 ± 3.07 mm; P < .001). The bilateral superior PV orifices, especially the right superior PV orifices were closer to the PAs than the inferior PV orifices (left superior PV: 7.59 ± 4.14 mm; right superior PV: 4.43 ± 2.51 mm; left inferior PV: 24.74 ± 5.26 mm; right inferior PV: 22.33 ± 4.75 mm) (P < .001). CONCLUSIONS: The right superior PV orifices were closer to the bronchi and PAs than other PV orifices. The ablation at the mid-posterior LA roof had a higher possibility to damage bronchi. CT is a feasible method to assess the anatomical adjacency in vivo, which might provide guidance for AF ablation.

Dual-Energy Computed Tomography-Enabled Material Separation in Diagnosing Left Atrial Appendage Thrombus.

We explored the potential clinical value of material separation enabled by dual-energy spectral computed tomography in detecting left atrial appendage thrombi. The study enrolled 24 patients who were scheduled to undergo atrial fibrillation ablation (12 with and 12 without left atrial appendage thrombi). Computed tomograms were acquired in gemstone spectral imaging mode; the densities in the regions of the left atrial appendage cavities, pectinate muscles, and left atrial appendage thrombi were analyzed on monochromatic 70-keV images. Iodine and blood were chosen as the material basis pair; the iodine and blood densities were observed and quantitatively determined from the iodine- and blood-specific material decomposition images. On the 70-keV monochromatic and iodine-specific images, the left atrial appendage pectinate muscles and thrombi appeared as areas of hypodense attenuation. On the blood-specific images, similar areas of high attenuation were observed in the thrombi and cavities, whereas lower attenuation was noticed in the pectinate muscles. The quantitative iodine and blood densities in the pectinate muscles were lower than those in the cavities (P <0.001). The iodine densities in the thrombi were lower than those in the cavities (P <0.001); however, blood densities did not differ significantly between the thrombi and cavities (P=0.192). Compared with the pectinate muscles, the thrombi showed lower blood-density differences (P=0.003) and higher iodine-density differences (P=0.006) in relation to the cavities. Spectral computed tomography-enabled material separation is a novel method for differentiating left atrial appendage thrombi from pectinate muscles. The potential applications of this technology warrant further studies.

CT imaging-based histogram features for prediction of EGFR mutation status of bone metastases in patients with primary lung adenocarcinoma.

OBJECTIVE: To identify imaging markers that reflect the epidermal growth factor receptor (EGFR) mutation status by comparing computed tomography (CT) imaging-based histogram features between bone metastases with and without EGFR mutation in patients with primary lung adenocarcinoma. MATERIALS AND METHODS: This retrospective study included 57 patients, with pathologically confirmed bone metastasis of primary lung adenocarcinoma. EGFR mutation status of bone metastases was confirmed by gene detection. The CT imaging of the metastatic bone lesions which were obtained between June 2014 and December 2017 were collected and analyzed. A total of 42 CT imaging-based histogram features were automatically extracted. Feature selection was conducted using Student's t-test, Mann-Whitney U test, single-factor logistic regression analysis and Spearman correlation analysis. A receiver operating characteristic (ROC) curve was plotted to compare the effectiveness of features in distinguishing between EGFR(+) and EGFR(-) groups. DeLong's test was used to analyze the differences between the area under the curve (AUC) values. RESULTS: Three histogram features, namely range, skewness, and quantile 0.975 were significantly associated with EGFR mutation status. After combining these three features and combining range and skewness, we obtained the same AUC values, sensitivity and specificity. Meanwhile, the highest AUC value was achieved (AUC 0.783), which also had a higher sensitivity (0.708) and specificity (0.788). The differences between AUC values of the three features and their various combinations were statistically insignificant. CONCLUSION: CT imaging-based histogram features of bone metastases with and without EGFR mutation in patients with primary lung adenocarcinoma were identified, and they may contribute to diagnosis and prediction of EGFR mutation status.

Imaging of Pericardiophrenic Bundles Using Multislice Spiral Computed Tomography for Phrenic Nerve Anatomy.

INTRODUCTION: Phrenic nerve injury and diaphragmatic stimulation are common complications following arrhythmia ablation and pacing therapies. Preoperative comprehension of phrenic nerve anatomy via non-invasive CT imaging may help to minimize the electrophysiological procedure-related complications. METHODS: Coronary CT angiography data of 121 consecutive patients were collected. Imaging of left and right pericardiophrenic bundles was performed with volume rendering and multi-planar reformation techniques. The shortest spatial distances between phrenic nerves and key electrophysiology-related structures were determined. The frequencies of the shortest distances ≤5 mm, >5 mm and direct contact between phrenic nerves and adjacent structures were calculated. RESULTS: Left and right pericardiophrenic bundles were identified in 86.8% and 51.2% of the patients, respectively. The right phrenic nerve was <5 mm from right superior and inferior pulmonary veins in 92.0% and 3.2% of the patients, respectively. The percentage of right phrenic nerve, <5 mm from right atrium, superior caval vein, and superior caval vein-right atrium junction was 87.1%, 100%, and 62.9%, respectively. Left phrenic nerve was <5 mm from left atrial appendage, great cardiac vein, anterior and posterior interventricular veins, and left ventricular posterior veins in 81.9%, 1.0%, 39.1%, 28.6%, and 91.4% of the patients, respectively. Merely 0.06% left phrenic nerve had a distance <5 mm with left superior pulmonary vein, and none left phrenic nerve showed a distance <5 mm with left inferior pulmonary vein. CONCLUSION: One-stop enhanced CT scanning enabled detection of phrenic nerve anatomy, which might facilitate avoidance of the phrenic nerve-related complications in interventional electrophysiology.

Application of spectral computed tomography dual-substance separation technology for diagnosing left ventricular thrombus.

OBJECTIVE: To investigate the value of spectral computed tomography (CT) dual-substance separation technology for diagnosing left ventricular (LV) thrombus. METHODS: In this observational case-control study, spectral CT scans were conducted in patients with and without LV thrombi. Densities in the regions of the LV cavity, papillary muscles and LV thrombus were observed on 140 kVp mixed-energy and 70 keV single-energy images. Iodine and blood were chosen as the base material pair, the densities were observed and the iodine and blood concentrations were quantitatively measured. RESULTS: A total of 24 patients were enrolled in this study. On iodine-based density images, both the LV thrombus and papillary muscles showed low-attenuation shadows. On blood-based density images, comparable high-density attenuation was found in the LV thrombus and LV cavity, while relative hypodensity was noted in the papillary muscles. Iodine and blood densities were significantly lower in papillary muscles than in the LV cavity. Iodine densities were significantly lower in the LV thrombus than the LV cavity, whereas blood densities in the two areas did not differ significantly. CONCLUSIONS: Spectral CT dual-substance separation technology and its derived images of iodine- and blood- based densities provide a new, simple, and feasible semiquantitative method to detect LV thrombus that warrants further investigation.

Imaging diagnosis for left ventricular thrombosis in idiopathic hypereosinophilic syndrome: two case reports.

Idiopathic hypereosinophilic syndrome (IHES) is a rare disease that is frequently associated with cardiac thrombosis and endocardial wall thickness. This case report describes 2 patients who had IHES associated with left ventricular (LV) thrombi. The patients' symptoms are atypical. Peripheral blood and bone marrow tests showed markedly elevated eosinophils. Electrocardiography showed ischemic changes in both patients. Negative computed tomography (CT) angiography excluded coronary artery stenosis. Transthoracic echocardiography (TTE), conventional multislice spiral CT, gemstone spectral CT, and cardiac magnetic resonance imaging were used to identify the LV intraluminal thrombus and endocardial thickening, and the diagnostic values of each imaging method were analyzed and compared. These patients were clinically diagnosed as "IHES, LV thrombosis, NYHA heart function classification I." Both patients received oral prednisone and warfarin therapy. At 5 month follow-up, TTE rechecks showed that the size of the LV thrombotic lesion was reduced in the first case but substantially increased in the second case.

Correlation of the UGT1A4 gene polymorphism with serum concentration and therapeutic efficacy of lamotrigine in Han Chinese of Northern China.

OBJECTIVE: The pharmacokinetics of lamotrigine (LTG) varies significantly among individuals and particularly among different ethnic groups. This is in part due to the presence of genetic polymorphisms affecting genes that metabolize LTG. UGT1A4 is a major metabolizing enzyme of LTG. The aim of this study was to investigate the effect of two UGT1A4 gene polymorphisms, UGT1A4 (70C > A) and UGT1A4 (142 T > G), on the levels and efficacy of LTG in Han Chinese patients with epilepsy. METHODS: The study cohort comprised 106 Han Chinese patients patients with epilepsy who were receiving LTG monotherapy. Blood samples were taken and LTG levels measured. The presence of UGT1A4 (70C > A) and UGT1A4 (142 T > G) was determined. The therapeutic efficacy of LTG at the 1-year time-point was assessed. RESULTS: All patients were homozygous for the CC genotype of UGT1A4 (70C > A), while the distribution of UGT1A4 (142 T > G) varied among patients. Two patients had a single nucleotide deletion at position 127 (UGT1A4 127delA). To evaluate the effect of the UGT1A4 (142 T > G) polymorphism on LTG pharmacokinetics, patients were divided into two groups. Group A included patients with the 142TG or 142GG polymorphism and Group B patients had the 142TT polymorphism. The normalized blood concentration and the efficacy of LTG were higher in Group B patients than in Group A patients (P < 0.05). The two patients with UGT1A4 127delA genotype had extremely high blood levels of LTG, and treatment was discontinued in one of these patients due to a severe LTG-associated rash. CONCLUSION: Patients with the UGT1A4 142TT polymorphism had a higher blood LTG concentration and better therapeutic efficacy, suggesting that this polymorphism influences LTG activity. The UGT1A4 127delA polymorphism significantly affected LTG levels and increased one of our patient's susceptibility to LTG-related adverse events.

[Clinical characteristics of triceps brachii tendon rupture at olecranon ending].

OBJECTIVE: To observe the clinical characteristics of triceps brachii tendon rupture at olecranon ending. METHODS: From June 2005 to November 2011,19 patients with triceps brachii tendon rupture at olecranon ending were treated with surgical technique. Among the 19 patients, 7 patients were male, with an average age of 24.1 years old (ranged, 15 to 41 years old); 12 patients were female, with an average age of 51.4 years old (ranged, 16 to 73 years old). Eight patients had injuries in the left elbows, and 11 patients had injuries in right elbows. Seventeen patients had injuries induced by walking fall and 2 patients had injuries induced by falling down. Thirteen patients were simple triceps brachii tendon rupture at olecranon ending, 6 patients were associated with other elbow injuries. Five patients were associated with radial fracture; 1 patient with capitellum fracture; 1 patient with coronoid process fracture; 1 patient with epitrochlear. All the lateral radiographs of the injuried elbow demenstrated the flecks of avulsed osseous material from the olecranon (flake sign). The associated injuries had the homologus presence. All the patients were treated with surgical techniques:15 patients were treated with figure-of-eight tension-band wire; figure-of-eight tension band wire and Kirschner wire in 1 patient; wire cerclage in 1 patient; nonabsorbable suture in 2 patients. The associated injuries were treated simultaneously. Plaster was applied after operation in 2 patients with heavier elbow associated injuries, other patients without any external fixation. The Mayo elbow score were observed to determinate the function of the elbow. RESULTS: All the patients were followed up, 1 patient died of other disease at one year after operation, the other 18 patients were followed up with an average of 47.9 months (ranged from 14 to 91 months). According to the Mayo elbow score, 16 patients got an excellent result and 2 good. CONCLUSION: Traumatic rupture of triceps brachii tendon at olecranon ending is not a rare injury, which is common in female older than fifty and in male younger then thirty. Surgical results are generally excellent. But dysfunction frequently remains in patients with associated elbow injuries.

[Clinical observation on percutaneous autologous bone marrow grafting for treatment of fracture nonunion].

OBJECTIVE: To observe the effectiveness of percutaneous bone marrow grafting for treatment of fractures nonunion. METHODS: From June 2001 to December 2007, 29 consecutive cases of fractures nonunion were treated with percutaneous autologous bone marrow grafting included 20 males and 9 females, ranging in age from 20 to 71 years, with an average of 40 years. All the cases were traumatic fractures involving 13 of tibia, 10 of femur, 3 of humerus, 2 of ulna, 1 of radius, 11 cases of them were open fractures. All the cases were performed internal or external fixation before marrow grafting, intramedullary pin in 15 cases, plate in 12 cases, external fixator in 2 cases. The time from injury to therapy were from 6 to 12 months, with an average of 8.5 months. The type of nonunion included atrophic in 26 cases,hypertrophic in 3 cases. All the cases were performed 3 times injection, the interval was 1 month. According to the different fracture, the amount of bone marrow was from 6 to 15 ml. RESULTS: All the 29 cases were followed-up for from 5 to 22 months with an average of 14 months. Four of them were not observed obvious callus after 3 months from the 3rd injection, judged unsuccessful therapy, changed to perform autologous bone grafting (3 of them re-internal fixation), the follow-up ended. The other 25 cases obtained bone union during 3 to 8 months with an average of 4.5 months, the follow-up ended at the time of internal fixation removal. CONCLUSION: Percutaneous autologous bone marrow grafting is an effective, easy and economic therapy for fracture nonunion. But stable internal or external fixation is the premise. Excessive bone defect, the gap more than 5 mm and mal-align requiring rectification is not appropriate for this therapy.