Detection and its clinical value of myocardial bridging with 64-slice spiral CT coronary angiography / 南方医科大学学报

<p><b>UNLABELLED</b>To evaluate the detection rate of myocardial bridging by 64-slice spiral CT coronary angiography.</p><p><b>METHODS</b>The data of 3011 patients with suspected coronary artery disease undergoing 64-slice spiral CT coronary angiography were collected and analyzed retrospectively.</p><p><b>RESULTS</b>A total of 174 cases (5.8%) with myocardial bridging were detected by 64-slice spiral CT coronary angiography, among which 168 (96.6%) had single foci of involvement and 6 (3.4%) had were multiple foci. Involvement of the left anterior descending coronary artery (LAD) was detected in 167 out of the 174 cases (96.0%). The length of the myocardial bridge varied between 5 and 120 mm (mean of 30.5 mm), and the depth of the tunneled artery ranged between 1.3 and 2.8 mm (mean 2.3 mm). Seventy-nine of the cases (45.4%) had uncomplicated myocardial bridging and 95 (54.6%) had myocardial bridging complicated by coronary atherosclerosis.</p><p><b>CONCLUSION</b>Multi-slice spiral CT coronary angiography is a reliable and noninvasive modality for diagnosis of myocardial bridging to allow direct measurement of the length and depth of the myocardial bridge and detection of concurrent coronary and cardiac lesions.</p>

Diagnostic value of 64-slice spiral CT coronary angiography for restenosis after bypass surgery / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the accuracy of 64-slice spiral CT in diagnosis of restenosis of coronary artery bypass grafts (CABG) and native coronary arteries in patients after bypass surgery.</p><p><b>METHODS</b>Fifty-eight patients receiving bypass surgery with totally 140 CABG (43 arterial and 97 venous grafts) were examined using 64-slice spiral CT. CABG and all native coronary arteries with a diameter of >1.5 mm were evaluated for the presence of significant stenoses (>50% diameter reduction) in comparison with the results by coronary angiography as the golden standard.</p><p><b>RESULTS</b>Of the 140 CABG examined, 38 were occluded and 104 remained patent, all of which were accurately identified by 64-slice spiral CT. The sensitivity of CT for restenosis detection in the patent graft was 100% (18/18) with a specificity of 95.2% (80/84). In the segmental evaluation of the native coronary arteries, the sensitivity of the CT in identifying significant stenosis in the evaluable segments (90%) was 84% (87/103) with a specificity of 74% (384/518). The accuracy of CT in detecting the presence of at least 1 stenosis in the CABG, distal runoff vessels or nongrafted arteries was 91% (53/58).</p><p><b>CONCLUSION</b>CT allows noninvasive angiographic evaluation of both the native coronary arteries and bypass grafts after bypass surgery.</p>

Grading of rabbit skeletal muscle trauma by diffusion tensor imaging and tractography on magnetic resonance imaging / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To distinguish the edema, injury, or rupture in the traumatic skeletal muscle fiber in vivo using diffusion tensor imaging (DTI) and tractography on magnetic resonance imaging (MRI).</p><p><b>METHODS</b>The skeletal muscle trauma models were made in 4 rabbits (eight hindlimbs) by iron discus (weight 1.0 kg, diameter 6 cm) falling down vertically from 45 cm height to rabbits' thighs. Conventional sequences and two-dimensional (2D) diffusion-weighted (DW) spin-echo (SE) echo planar imaging (EPI) sequence with fat suppression (b = 600 s/mm2) were performed on 1. 5T MRI scanner. The grading of edema, injury, and fiber rupture in the damaged muscle were made according to their histopathological views, which was consistent with the images. The mean apparent diffusion coefficient (ADC) values and fractional anisotropy (FA) values were measured from the region of interests (ROIs) of all groups on 2D DW images used for tractography. Analysis of variance test was performed to analyze all data.</p><p><b>RESULTS</b>ADC values of the areas in normal muscle, edema muscle, injury muscle, and ruptured muscle were (6.12 +/- 1.34) x 10(-3), (6.38 +/- 1.30) x 10(-3), (8.06 +/- 0.97) x 10(-3), and (9.57 +/- 0.93) x 10(-3) mm2/s, respectively. There was significant difference among groups (P < 0.001), but no difference between edema muscle and normal muscle group (P > 0.05). The FA values of normal muscle, edema muscle, injury muscle, and ruptured muscle were 0.42 +/- 0.12, 0.36 +/- 0.12, 0.26 +/- 0.09, 0.12 +/- 0.08, respectively, with a significant difference among groups (P < 0.001). In the edema muscle, the tracking cross-fiber could be seen but it decreased slightly. In the injury muscle, the tracking fiber decreased markedly. In the ruptured muscle, the transverse-orientation tracking fiber vanished, yet some interrupted longitudinal-orientation tracking fiber could be found.</p><p><b>CONCLUSION</b>The edema, injury, and rupture of muscle fiber in rabbit damaged skeletal muscle can be verified according to the ADC and the FA on DTI and tractography.</p>