Detection of abnormal myocardial blood supply caused by myocardial bridge using myocardial perfusion imaging and CT coronary angiography / 中华核医学与分子影像杂志

Objective To evaluate the cause of ischemia related to myocardial bridge (MB) by using SPECT/CT MPI and CTCA.Methods A total of 294 patients with chest pain,tightness or palpitation undergoing both CTCA and MPI were retrospectively enrolled in this study from March 2008 to March 2013.Among them,49 patients (26 males,23 females,age:32-85 (55.4± 16.6) years) had MB.Locations of MB and myocardial ischemia were recorded.Fused MPI/CTCA was analyzed.If there was no mural atherosclerotic plaque-related stenosis on CAG at the same location of coronary artery where ischemic myocardium was found,then MB was considered as the ischemic cause.Myocardial ischemia rates of different MB locations were compared by x2 test.Results Among 49 patients with MB,3 cases had MB in proximal segment of LAD,34 in mid LAD,4 in distal LAD,3 in septal branch,2 in distal LCX,1 in intermedius,and 2 in mid RCA.There were 41 cases with myocardial ischemia.Myocardial ischemia in 32 cases was caused by MB,including 23 caused by MB in mid LAD.The myocardial ischemia rates of the most common MB location (mid LAD,n =34) and other locations (n =15) were not significantly different (67.6％ (23/34) vs 60.0％ (9/15),x2 =0.27,P＞0.05).Conclusions MB is commonly found in the mid LAD.The myocardial ischemia rates caused by MB is not related the MB location.Hybrid MPI/CTCA could evaluate the sites of coronary MB and myocardial ischemia simultaneously and therefore may be useful to evaluate the relationship between MB and myocardial ischemia.

The relative renal safety of iso-osmolar contrast media compared with low-osmolar contrast media in intravenous contrast-enhanced CT: a Meta-analysis / 中华肾脏病杂志

Objective To compare the nephrotoxicity of the iso-osmolar contrast media (iodixanol) to low-osmolar contrast media (LOCM) in intravenous contrast-enhanced CT.Methods Randomized controlled trials (RCTs) of iodixanol or low-osmolar contrast media in intravenous contrastenhanced CT were searched in the database of VIP,CBM,CNKI,Wanfang,PubMed,EMBASE,Web of Science,Cochrane Library from their start year to July 2012.Screening and information extracted were did by two researchers independently.The quality of the included documents was evaluated by the criterion of Cochrane handbook.Revman software (version 5.0) of the Cochrane collaboration was used in data analysis.Results There was no significant difference in the incidence of contrast-induced nephropathy (CIN) among 6 trials recruited 907 patients between the iodixanol group and the LOCM group [RR =0.64,95％CI (0.31-1.32),P=0.22] by using serum creatinine increased by more than 44 μmol/L (0.5 mg/dl) as the diagnostic criteria.No considerable difference was existed by using serum creatinine increased by more than 25％ as the diagnostic criteria between the two groups [RR =0.79,95％CI (0.48-1.30),P =0.35].Subgroup analysis showed there was no obvious difference [RR =0.57,95％CI (0.30-1.10),P =0.09] between the two groups in patients with increased baseline of serum creatinine.No obvious difference were gained in normal baseline group [RR =1.28,95％CI (0.57-2.86),P =0.55].Conclusion Compared with low-osmolar contrast media,iodixanol is not associated with less CIN in intravenous contrast-enhanced CT.

Clinical value of CT Airbronchogram in diagnosis of Peripheral Bronchogenic Carcinoma / 中国基层医药

Objective To explore the clinial value of airbronchogram in diagnosis of peripheral lung cancer (diameter≤3). Methods Comparing study between thin section CT and pathology was done on 174 nodules (129malignant and 45 benigin) in 150 patients. Results Thin section CT showed 30 cases (23%) of airbronehogram in nodules,only seen in bronchioalveolocarcinoma, adenocarcinoma and squamous cell carcinoma (significance difference). Conclusion Airbronchogram in peripheral small nodules was a certain sign of malignant nodule. The sign suggested diagnosis of histologic types in lung center.

Evaluation of 10 mAs and low-contrast CT image optimization based on the multitractal spectrum in brain of infant / 中华放射医学与防护杂志

Objective To analyze scanned image optimization based on the multifractal soectrum and image fractal algorithm of 64-slice spiral CT in brain of infant. Methods The image data of Toshiba Aquilion 64-slice CT scanning using 10 mAs were imported to image processing toolboxs of Matlab 7.1. The evaluation of muhifractal spectrum and image denosing were performed, and compared with image quality of conventional low-dose CT using 50 mAs. Results The low-contrast scanned image used 10 mAs is the valueless medical image because of serious noise. Image denoise based on the fractal model had superior characteristic of image detail preserving and better contrast-to-noise ratio(CNR). There existed a group difference in the score of image quality between the rude imaging noise and optimized image based on the muhffraetal spectrum algorithm, though the score was still significantly lower than the normal dosage scanned image(F = 38.85, P < 0.01). The group difference was also manifested the image quality of infants can achieve basieaUy the request of clinical diagnosis by suitable model denoising algorithm. Conclusions Image denoising based on the multifraetal spectrum model can be used on the low-dose and low-contrast CT image optimization. It improved the CNR of the pathological region. The radiation dose of CT scanning in infants would be declined significantly by its further application in the future.

Anterior Chamber Measurements by Pentacam and AS-OCT in Eyes With Normal Open Angles

PURPOSE: To assess the reproducibility and agreement of anterior chamber measurements between the Pentacam (PTC) and the Anterior segment optical coherence tomography (AOCT) in normal healthy eyes with open angle. METHODS: Prospective cross-sectional comparative case series. A total of 162 eyes of 81 healthy volunteers with normal open angle were included in this study. Anterior chamber angle (ACA) and anterior chamber depth (ACD) were measured with PTC and AOCT. Intra-observer variability and inter-methods agreement of both instruments for ACA and ACD were evaluated. RESULTS: Values of temporal and nasal ACA measured by two instruments were similar, and the results of ACD were also not significantly different between modalities (p>0.01). ACA and ACD measurements by PTC and AOCT showed good intra-observer and inter-method agreements (all >0.9). CONCLUSIONS: PTC and AOCT are presumed to be very useful for the anterior chamber angle examination. They may provide good images and quantitative data about the angle structures including ACA and ACD.

The diagnostic value of coronal airway CT scan for foreign body aspiration in children / 重庆医科大学学报

Objective; To investigate the diagnostic value of coronal airway CT scan for foreign body aspiration in children. Methods; The X rays and CT findings in 51 cases of foreign body aspiration confirmed by endoscopy were reviewed . Results; The shape and location of foreign body in 51 cases were all distinctively showed on CT images. 6 of 8 cases of tracheal foreign body aspiration and 37 of 43 cases of bronchial foreign body aspiration were diagnosed with radiographic signs. Conclusion; The coronal CT scan has a compacity of demonstrating the foreign body intensively and dinstinctively, and can be used as an important diagnostic method for foreign body aspiration.

Noninvasive Evaluation of Coronary Artery Bypass Graft Patency by Electron Beam Tomography / 대한흉부외과학회지

Recently non-invasive diagnostic imaging replaced the invasive catheter angiography in the diagnosis of vascular disease. Catheter methods are now almost confined to the purpose of intervention. Coronary artery or coronary artery bypass graft still needs catheter technique because of small diameter and the cardiac motion. The last challenge for radiologists in this domain is to obtain a non-invasive imaging. Electron beam tomography(EBT) for high temporal resolution is able to obtain a coronary arteriogram or coronary artery bypass graft (CABG), of which CABG imaging is quite useful for the evaluation of patency. In our experience as well as others, the accuracy of EBT angiogram in evaluating CABG patency revealed that the accuracy of patency of saphenous vein grafts(SVG) is high due to relatively wide lumen, short and straight course and less influence from cardiac motion. The sensitivity and specificity of patency of SVGs were 92%, 97% respectively in the prospective evaluat on and 100% each in the retrospective evaluation. A false positive and a false negative case are rudimentary errors in the initial learing period. In contrast the analysis of left internal mammary artery(LIMA) graft was difficult due to the inherent small size and the adjacent surgical clips provoking beam-hardening artifact; therefore, the method of combining 3 dimensional reconstruction and flow mode study was important in improving the accuracy of LIMA patency. The sensitivity and specificity of LIMA patency were 100% and 80% in both prospective and retrospective evaluation. Therefore, EBT angiography is an accurate non-invasive diagnostic modality for evaluating the patency of CABG, particularly in SVGs. The accuracy can be improved with the improvement of the EBT and the development of the image reconstruction software.

CT Angiography in the Diagnosis of Cerebral Aneurysm: Comparison of MIP and SSD Techniques

PURPOSE: To evaluate the usefulness of CT angiography and to compare SSD(Shaded Surface Display) andMIP(Maximum Intensity Projection) in the diagnosis and preoperative evaluation of the cerebral aneurysms. MATERIALS AND METHODS: Twenty-six aneurysms in 20 patients were diagnosed on conventional angiography and surgerywas performed. For preoperative evaluation, all patients underwent CT angiography, with spiral CT for preoperativeevaluation. Using SSD and MIP techniques, the results were proccessed and compared; three radiologistsretrospectively analysed detectability, size, neck visualization, delineation of shape, direction, therelationship with surrounding vessels-including the feeding artery of the aneurysm-and intraluminal thrombicontaining calcification. RESULTS: Twenty five of 26 aneurysms (96.2%) were detected by CT angiography, while MIPand SSD depicted 25 (96.2%) and 24 (92.3%), respectively. The largest diameter of the aneurysms was 11-15mm infour cases, 6-10mm in ten, and 3-5mm in 12 (mean 7.38mm, SD=3.34). With regard to detectability, MIP led to onefalse negative result, and SSD to two false negative and one false-positive results. Aneurysm neck assessment byMIP was clear in 96.0% of cases (24/25), and by SSD in 83.3% (20/24). For the depiction of directions and feedingvessels of the aneurysms, and intraluminal thrombi containing calcification, MIP was superior to SSD, while fordepicting shape and the relationship with surrounding structures, SSD was superior to MIP. CONCLUSION: For theassessment of cerebral aneurysms, MIP is somewhat superior to SSD. The characteristics of aneurysms and theirrelationship with surrounding structures can, however, be better evaluated by combining the two techniques.