The Significance Of Preoperative CTA For Interventional Treatment Of Bronchiectasis-Caused Hemoptysis

ObjectiveTo examine the significance and clinical value of preoperative bronchial artery (BA) imaging by 64-slice spiral CT for the localization of regular and ectopic blood vessels in BA embolization.Materials and methodsThirty six patients treated at the Third Affiliated Hospital of Jilin University from August 2007 to March 2009 were selected for the study, who were admitted for repeated or massive hemoptysis and underwent preoperative 64-slice spiral CTA before BA embolization. Within the 37 cases, 28 were diagnosed with bronchiectasis, 4 with primary pulmonary carcinoma accompanied by bronchiectasis, 2 with tuberculosis, 2 with arteriovenous fistula and 1 with bronchiectasis accompanied by BA aneurysm. All of the 37 patients received DSA examination.Ultravist 370 (80-90 mL) was injected via ulnar vein at 3.0-4.0 mL/s, and the delay time was set at 20-35 s. Then a LightSpeed VCT System 64-slice spiral CT was employed to scan the area from C6 to T10. The scanning parameters were set as: rotation speed at 0.32 s/r, tube voltage at 125-140 kV, tube current varied by individual cases (typically 250-350 mA), pitch at 0.984, slice thickness at 0.625 mm, reconstruction interval at 0.625 mm, FOV at 350 mm and a matrix of 512×512. The CT data were then transferred to a GEAW 4.3 workstation. Multiple reconstruction methods were employed for image processing, including MIP, VR, MPR and CPR. Based on the CTA results, BA catheterization was performed under the guidance of DSA via the following procedures. A 6F artery sheath was inserted into the femoral artery after percutaneous puncture through Seldinger technique. Subsequently, depending on individual cases, a Cobra catheter (4-5F) or BA catheter was applied. All the data were analyzed by theχ2 test with the SPSS 15.0 software. P<0.05 represented statistical significance.Results In the 37 cases examined in this study, 49 right BAs and 40 left BAs were clearly detected, at 1.32 per cases and 1.08 per case respectively. Six distribution patterns of BA were observed in the study group, where the right and left BA were represented by R and L, and the number of branches by n. The most common pattern was R1L1 (18/37, 48.6%) followed by R2L1 (6/37, 16.2%). Most of the detected right BAs originated from the aorta descendens (24/49, 49.0%) and the right posterior intercostal artery (23/49, 46.9%), while the left BAs predominantly originated from the aorta descendens (36/40, 90.0%). Origin sites other than the right posterior intercostals artery or the aorta descendens were defined as ectopic for the right BA, whereas sites other than the aorta descendens or the arcus aortae as ectopic for the left BA. Two out of the 49 detected right BAs (4.1%) were ectopic, originating from the right subclavian artery on a common trunk; while two out of the 40 left BAs (5.0%) was ectopic, originating from the proximal termini of the left internal thoracic artery and the left common carotid artery respectively. These ectopic BAs were detected in 11 cases. In the BAs that originated from the aorta descendens, the origins of the right BA were located at the right lateral wall (13/24, 54.2%) and the anterior wall (11/24, 45.8%), while the origins of the left BA at the anterior wall (31/36, 86.1%) and the right lateral wall (5/36, 13.9%). Most of the detected 89 BAs originated at the T5-T6 level, accounting for 89.8% (44/49) of the right BAs and 90.0% (36/40) of the left BAs respectively. In general the origin position of the right BAs was slightly higher than the left BAs. Compared with DSA as the standard on the number of detected BA, CTA turned out to be highly sensitive (94.6%) and specific (100%) for BA imaging.BAs were observed to be markedly dilated (average diameter at 2.2 mm) and tortuous by CTA imaging in all of the 37 cases. Consistent with the CTA results, DSA imaging also displayed a plexiform pattern with dilated BA trunk, multiplied branches that were tortuous and broaden. Based on the CTA results, embolization of the bleeding BA was performed under the guidance of DSA, during which the contrast material leaked from the distal terminus of the BA.ConclusionThe present study suggests that CTA is a highly sensitive and specific technique for BA imaging. CTA can faithfully depict the morphology, number and running course of the target blood vessels. CTA has a high detection rate for ectopic BA and can accurately localize the origin of ectopic BA. In addition, CTA produces three-dimensional, directing-viewing images that can be rotated arbitrarily, so that the chance of missed diagnosis is decreased. In clinical practice, BA-CTA provides important evidence for the diagnosis of bronchiectasis. Accurate localization of the bleeding vessels by preoperative BA-CTA can increase the success rate of catheterization, shorten the time of operation, and significantly reduce the exposure of the patient and the operator. Consequently, CTA provides critical information and strong support for formulating the therapeutic strategy, selecting the right catheter, pathway and embolization materials. As a non-invasive technique, CTA spares the patients from invasive measures such as DSA, and at the same time offers a new effective examination.