Aortoarteritis of abdominal aorta: an angiographic profile in 110 patients

Follow-up CT evaluation of the mural changes in active Takayasu arteritis

Objective

We wanted to evaluate the mural changes by CT on the follow-up examination of patients with active Takayasu arteritis.

Materials and Methods

The study included 18 patients, (4 males and 14 females), with active Takayasu arteritis. A total of 44 CT examinations were done during the follow-up period (mean: 55.6 months). At the time of the last follow-up CT, the disease, on the basis of the erythrocyte sedimentation rate (ESR), was found to be inactive in five patients and the disease was active and persistent in 13 patients. The thickness and CT attenuation of the aortic wall on the precontrast, arterial and venous phases were measured on the initial and the follow-up CT examinations. The ratio of the mural attenuation over that of the back muscle on the initial CT was compared with the ratio found on the follow-up CT.

Results

The initial CT findings included high density and calcifications of the aortic wall in the precontrast images and a thickened wall with enhancements in the arterial and the venous phases. A low-attenuation ring was demonstrated in the venous phase in 15 patients (83%). On the follow-up evaluation, the mean mural thickness decreased significantly from 4.1 mm to 2.4 mm. The mean mural attenuation ratio in the venous phase decreased significantly from 1.9 to 1.3 (p = 0.001). The low attenuation ring was identified in seven patients (39%) who had only with active, persistent Takayasu arteritis.

Conclusion

The mural changes demonstrated by the follow-up CT evaluations for the patients with active Takayasu arteritis included a decrease of the mural thickness and enhancement, disappearance of the low-attenuation ring on the venous phase, and an increase of the mural attenuation and calcification on the precontrast phase.

The role of B-mode ultrasonography and electron beam computed tomography in evaluation of Takayasu's arteritis: a study of 43 patients

OBJECTIVES

To evaluate the capacity of B-Mode ultrasonography (B-Mode US) and electron-beam computed tomography (EBCT) to detect arterial changes in Takayasu's arteritis.

METHODS

EBCT angiography of the thoracoabdominal aorta and pulmonary artery, and B-mode US of large superficial arteries (common carotid, subclavian, and common femoral arteries) were performed prospectively in 43 consecutive patients with established Takayasu's arteritis. The arterial wall thickness was measured, and lumen changes (stenosis, aneurysm) were noted.

RESULTS

The combined results of B-Mode US and EBCT examinations showed that every patient had at least one abnormality at the studied sites. The median score of abnormal sites was 7. The most frequent lesion was a characteristic long, homogeneous, circumferential thickening, visualized in 52% of examined sites and in all patients but one (98%). Stenosis was detected by US and by EBCT, respectively, in 44% and 32% of patients, and aneurysm in 0.4% and 68%.

CONCLUSIONS

In Takayasu's arteritis, B-Mode US and EBCT was able to visualize the classical caliber abnormalities (stenosis, aneurysm) and, in contrast to angiography, to depict vessel wall thickening, a major pathologic feature of the disease. Both these safe techniques seem more useful than angiography to characterize and map the vascular lesions of Takayasu's arteritis.

Magnetic resonance imaging diagnosis of Takayasu arteritis

Conventional angiography has been used for diagnosis of Takayasu arteritis (TA). In early stage of TA, subtle inflammatory wall thickening of the aorta and its branches without significant stenosis may be the only morphologic change of TA. Magnetic resonance (MR) imaging appears to be useful in the diagnosis of early stage TA by visualizing concentric wall thickening of the vessels. T2-weighted images may show bright signal of edema in and around the inflamed vessel. Contrast media-enhanced MR shows enhanced wall of vessels even in chronic stage, which may indicate the activity of TA at the tissue level. MR angiography allows us noninvasive assessment of the vascular tree and it may replace conventional angiography.

Biomechanics of abdominal aortic aneurysm in the presence of endoluminal thrombus: experimental characterisation and structural static computational analysis

OBJECTIVES

To evaluate the role played by biomechanical and geometrical parameters of endoluminal thrombus and of aortic wall on abdominal aortic aneurysm (AAA) behaviour.

MATERIALS AND METHODS

Tensile tests on 21 AAA thrombus specimens from six patients undergoing AAA repair and numerical evaluation of aneurysmal aortic wall stress and strain distribution. Parameters of the analysis were lumen eccentricity, thrombus Young's Modulus and the aortic wall constitutive equation.

RESULTS

There was a linear stress/strain for all the thrombus specimens. The numerical analyses show the mechanical behaviour of AAA as a function of lumen eccentricity and biomechanical parameters.

CONCLUSIONS

Well organised thrombus reduces the effect of the pressure load on the aneurysmal aortic wall.