High-resolution CT Features of Bleeding Foci in Patients with Massive Hemoptysis

PURPOSE: To compare the high-resolution CT features of bleeding foci in patients with massive hemoptysis during embolization with those revealed by angiography. MATERIALS AND METHODS: Between June 1997 and June 1999, we evaluated 25 patients who from among a total of 49 with arterial embolization due to massive hemoptysis underwent HRCT prior to embolization. We retrospectively analyzed medical records, and angiographic and HRCT findings. The time interval between HRCT and arterial embolization varied from two hours to six days. Angiography indicated that the bronchial, intercostal and internal mammary artery, and branches of the subclavian, were the foci of bleeding, and indicated the location of these in each pulmonary lobe. The HRCT findings were evaluated in terms of cavity, air-meniscus sign, bronchial dilatation, consolidation, ground-glass opacity, and fibrotic scar. We analyzed the corresponding sites of HRCT and the angiographic findings of the foci of bleeding. RESULTS: In 24 of 25 patients, the foci of bleeding were angiographically confirmed, their presence being noted in 28 pulmonary lobes. HRCT findings corresponding to the bleeding foci revealed by angiography were the air-meniscus sign (8 of 10 lobes, 80.0%), cavity (7 of 9 lobes, 77.8%), bronchial dilatation (21 of 30 lobes, 70.0%), and fibrotic scar (1 of 23 lobes, 4.3%). The findings in areas of consolidation and/or ground-glass opacity only did not correspond, however. CONCLUSION: As compared with those revealed by angiography, the HRCT features of bleeding foci in patients with massive hemoptysis during embolization are in order of frequency, the air-meniscus sign, cavity, and bronchial dilatation.

Gadolinium-Enhanced MR Angiogra p hy of Arterial Occlusive in Lower Extremity: Comparison with Conventional Digital Substraction Angiography

PURPOSE: To compare the diagnostic value of gadolinium-enhanced MR angiography with that of conventional digital substraction angiography for the evaluation of lower extremity arterial occlusive diseases. MATERIALS AND METHODS: In 26 patients with symptomatic lower extremity arterial occlusive disease, both conventional digital substraction angiography(DSA) and gadolinium-enhanced MR angiography (CE-MRA) were performed during the same week. MR angiography was performed using three-dimensional gradient-echo ac-quisition before, and two sequential acquisitions after, the administration of gadolinium(0.2 mmol/kg). In 23 patients, two separate, contiguous areas were scanned using additional doses. In three patients, only one field with a suspicious lesion was scanned. Three radiologists independantly analysed the CE-MRA and DSA find-ings of each vascular segment(20 segments per arterial tree) for the presence of obstructive lesions; the grade assigned was either mild or none (>50 %), stenotic(50 %-99 %),or occlusion(100 %). RESULTS: From among a total of 462 segments, DSA detected 99 which were significantly narrowed (stenosis, 33; occlusion, 66). Using MR angiography, 102 segments(stenosis 39; occlusion, 63)were identified, and 94 lesions (stenosis, 32; occlusion 62) were graded correctly. Seven lesions were overestimated and four were un-derestimated. For the detection of hemodynamically significant stenosis or occlusions using MR angiography, sensitivity, specificity, and diagnostic accuracy were 95%, 98%, and 98% (G=0.995, P<0.001), respectively. To prove the absence of lesions, we repeated DSA in two patients with arterial spasm due to puncture. Three occluded segments seen on DSA, which revealed intact segments on MR angiography, suggested slow distal flow after reconstitution. CONCLUSION: For the evaluation of lower extremity arterial occlusive disease, the diagnostic value of gadolini-um-enhanced MR angiography is comparable with that of digital substraction angiography. The advantages of the former are the absence of puncture-related spasm and visualization of slow distal flow.

Breath-Hold Gadolinium-enhanced MRA: Clinical Application

PURPOSE: To compare breath-hold gadolinium enhanced MR angiography(MRA) with digital subtraction angiography. MATERIALS AND METHODS: Ten patients underwent angiography and breath-hold gadolinium enhanced MRA;the latterperformed at 1.5T with 3D FSPGR after a bolus injection of gadopentetate dimeglumine(0.4mmol/kg) RESULTS: Sevenof ten pathologic conditions(70%) evaluated by both techniques had a similar appearance. The conditions examinedwere as follows : the artery feeding renal cell carcinoma(n=2): renal artery stenosis(n=2); pulmonaryAVM(n=2);abdominal aortic aneurysm(n=1); atheromatous plaque in the lower abdominal aorta(n=1);an enlargedbronchial artery(n=1); and an aberrant renal artery(n=1). For evaluating an anatomic relationship, a reconstructed3D image obtained by MRA is more advantageous. CONCLUSION: Breath hold contrast enhanced MRA is a potentiallyuseful noninvasive screening method for detecting vascular abnormality of the aorta and its branches.