Endovascular repair of inflammatory aortic aneurysms: long-term results

OBJECTIVE: Our objective was to report the long-term follow-up results of endovascular aneurysm repair of inflammatory aortic aneurysms. CONCLUSION: Endovascular aneurysm repair of inflammatory aortic aneurysms excludes the aneurysm and seems to reduce the size of the aneurysmal sac and the extent of periaortic fibrosis with acceptable periinterventional and long-term morbidity.     

Inflammatory abdominal aortic aneurysm: a cause of urinary obstruction and acute renal failure

Abdominal aortic aneurysms are rare causes of ureteric obstruction. We report three cases of inflammatory abdominal aortic aneurysm producing hydronephrosis. In two patients acute renal failure preceded this presentation. The diagnosis can be established by computed tomography when mural thrombus, wall calcification, and an enhancing periaortic soft-tissue mantle are present. It is important to recognize this disease preoperatively.     

Infected aortic aneurysms: imaging findings

PURPOSE: To determine the imaging characteristics of infected aortic aneurysms. MATERIALS AND METHODS: Review of records of patients with surgical and/or microbiologic proof of infected aortic aneurysm obtained over a 25-year period revealed 31 aneurysms in 29 patients. This study included 21 men and eight women (mean age, 70 years). One radiologist reviewed 28 computed tomographic (CT) studies (22 patients underwent CT once and three patients underwent CT twice), 12 arteriograms (12 patients underwent arteriography once), eight nuclear medicine studies (six patients underwent nuclear medicine imaging once and one patient underwent nuclear medicine imaging twice), and three magnetic resonance (MR) studies (three patients underwent MR imaging once). Features evaluated included aneurysm size, shape, and location; branch involvement; aortic wall calcification; gas; radiotracer uptake on nuclear medicine studies; and periaortic and associated findings. The location of infected aortic aneurysms was compared with that of arteriosclerotic aneurysms. RESULTS: Aneurysms were located in the ascending aorta (n = 2, 6%), descending thoracic aorta (n = 7, 23%), thoracoabdominal aorta (n = 6, 19%), paravisceral aorta (n = 2, 6%), juxtarenal aorta (n = 3, 10%), infrarenal aorta (n = 10, 32%), and renal artery (n = 1, 3%). Two patients had two infected aortic aneurysms. CT revealed 25 saccular (93%) and two fusiform (7%) aneurysms with a mean diameter at initial discovery of 5.4 cm (range, 1-11 cm). Paraaortic soft-tissue mass, stranding, and/or fluid was present in 13 (48%) of 27 aneurysms, and early periaortic edema with rapid aneurysm progression and development was present in three (100%) patients with sequential studies. Other findings included adjacent vertebral body destruction with psoas muscle abscess (n = 1, 4%), kidney infarct (n = 1, 4%), absence of calcification in the aortic wall (n = 2, 7%), and periaortic gas (n = 2, 7%). Angiography showed 13 saccular aneurysms with lobulated contour in 10 (77%). Nuclear medicine imaging showed increased activity consistent with infection in six (86%) of seven aneurysms. MR imaging showed three saccular aneurysms. Adjacent abnormal vertebral body marrow signal intensity was seen in one (33%) of three patients. CONCLUSION: Saccular aneurysms (especially those with lobulated contour) with rapid expansion or development and adjacent mass, stranding, and/or fluid in an unusual location are highly suspicious for an infected aneurysm.     

CT appearance of mycotic abdominal aortic aneurysms

The CT appearance of three cases of infected aortic aneurysms is reported with clinical and pathological correlation. Two of our cases had unique features: the disappearance of aortic calcifications, and an irregular, thickened aortic wall with peripheral enhancement. The nonspecific clinical presentation and high mortality make mycotic aneurysm an important consideration in the differential diagnosis of abnormal soft tissue contiguous with the aorta.     

Detection of inflammation in aortic aneurysms with indium 111-oxine-labeled leukocyte imaging

BACKGROUND: The exact cause of aortic aneurysms is not completely understood. Histologically, the atherosclerotic lesions present in an aneurysm contain numerous inflammatory cells. This finding represents active atherosclerosis, which can cause lesion expansion. In this study we investigated the role of scintigraphy in the evaluation of inflammation in aortic aneurysms. METHODS AND RESULTS: We performed imaging using indium 111-oxine--labeled leukocytes in 14 patients with aortic aneurysms (10 thoracic and 4 abdominal) diagnosed by computed tomography. Peripheral blood evidence of inflammation was assessed on the same day. In 8 patients who subsequently underwent graft replacement of the aneurysm, the excised specimen was examined for evidence of inflammatory infiltration and correlated with the scintigraphic findings. Scintigraphic accumulation of labeled leukocytes was present in 10 of the 14 patients. Although all patients had a small increase in the erythrocyte sedimentation rate, there was no significant difference in the erythrocyte sedimentation rate between patients with positive and negative scintigram results. In 5 of the 8 surgical patients with positive scintigram results, the resected specimens demonstrated numerous inflammatory cells in the adventitia of the aortic wall and atherosclerotic changes in the media. There was no correlation between the presence of periaortic inflammatory adhesions at the time of surgery and the scintigraphic results. CONCLUSIONS: The accumulation of In-111-oxine--labeled leukocytes is a potentially useful scintigraphic marker of inflammatory infiltration in aortic aneurysms.     

Infectious or Noninfectious? Ruptured, Thrombosed Inflammatory Aortic Aneurysm with Spondylolysis

Osteolysis of vertebrae due to inflammatory aortic aneurysm is rarely observed. However, it is estimated that up to 10 % of infectious aneurysms coexist with bone tissue destruction, most commonly the vertebrae. Inflammatory aneurysms with no identified infection factor, along with infiltration of adjacent muscle and in particular extensive destruction of bone tissue have rarely been described in the literature. A case of inflammatory aneurysm with posterior wall rupture and inflammatory infiltration of the iliopsoas muscle and spine, together with extensive vertebral body destruction, is presented. The aneurysm was successfully treated with endovascular aneurysm repair EVAR.     

Aneurysmal wall enhancement and perianeurysmal edema after endovascular treatment of unruptured cerebral aneurysms

Introduction

Perianeurysmal edema and aneurysm wall enhancement are previously described phenomenon after coil embolization attributed to inflammatory reaction. We aimed to demonstrate the prevalence and natural course of these phenomena in unruptured aneurysms after endovascular treatment and to identify factors that contributed to their development.

Methods

We performed a retrospective analysis of consecutively treated unruptured aneurysms between January 2000 and December 2011. The presence and evolution of wall enhancement and perianeurysmal edema on MRI after endovascular treatment were analyzed. Variable factors were compared among aneurysms with and without edema.

Results

One hundred thirty-two unruptured aneurysms in 124 patients underwent endovascular treatment. Eighty-five (64.4 %) aneurysms had wall enhancement, and 9 (6.8 %) aneurysms had perianeurysmal brain edema. Wall enhancement tends to persist for years with two patterns identified. Larger aneurysms and brain-embedded aneurysms were significantly associated with wall enhancement. In all edema cases, the aneurysms were embedded within the brain and had wall enhancement. Progressive thickening of wall enhancement was significantly associated with edema. Edema can be symptomatic when in eloquent brain and stabilizes or resolves over the years.

Conclusions

Our study demonstrates the prevalence and some appreciation of the natural history of aneurysmal wall enhancement and perianeurysmal brain edema following endovascular treatment of unruptured aneurysms. Aneurysmal wall enhancement is a common phenomenon while perianeurysmal edema is rare. These phenomena are likely related to the presence of inflammatory reaction near the aneurysmal wall. Both phenomena are usually asymptomatic and self-limited, and prophylactic treatment is not recommended.     

Direct visualization of intracranial aneurysms by computed tomography

Twenty seven aneurysms in 25 patients were directly visualized by CT. Thin-walled non-thrombosed aneurysms showed homogeneous sharply-marginated intraluminal enhancement. Partially thromhosed aneurysms had a thickened high-density peripheral rim which was sometimes calcified and enhanced; the intraluminal portion also enhanced but the thrombosed region was isodense and non-enhancing. Completely thrombosed aneurysms showed dense calcification in the peripheral wall with sometimes peripheral but no intraluminal enhancement.     

Role of x-ray computed tomography in the preoperative evaluation of aneurysm of the abdominal aorta

The authors have studied the files of 50 consecutive patients (1987-89) operated for abdominal aortic aneurysm (AAA) and examined with CT. The criteria for inclusion were surgical features. CT can be made more accurate for the study of AAA: Thus the location of the neck of the aneurysm relative to the renal arteries was defined in 94% of all cases. In addition, CT yields information about the wall of the aneurysm, whether it be thickened (3 inflammatory aneurysms were properly diagnosed) or, mor importantly, weakened (solution of continuity in the wall in the "prior-to-rupture" appearance). Owing to the quality of its performances and to its noninvasive character, the authors regard CT with contrast injection as an essential technique for the preoperative assessment of abdominal aortic aneurysm in most cases. The examination must be carried out strictly, especially for the contiguous sections of the renal arteries and their extension to the crural arch. As it demonstrates weakened areas more easily, a more accurate study of the aneurysmal wall with CT might increase the surgical indications for some smaller aneurysms, the potential evolution of which does not seem to be associated with their diameter only.     

Blood pool MR angiography of aortic stent-graft endoleak

OBJECTIVE: The purpose of our research was to investigate the value of a blood pool contrast agent in detecting endoleaks on MR angiography after endoluminal stent-graft repair of infrarenal aortic aneurysms. CONCLUSION: Blood pool MR angiography using Ferumoxytol reveals more aortic stent-graft endoleaks than does CT angiography and depicts more endoleaks 24 hr after administration than during the immediate arterial phase because of a 50-fold increase in the volume of enhancement in the aneurysmal sac outside the stent-graft.     

The radiologic diagnosis of inflammatory aneurysms

An inflammatory aneurysm is defined as a nonbacterial special type of atherosclerotic aneurysm. The macroscopic characteristics are: a porcelaneous appearance, excessive thickening of the aortic wall, and perianeurysmal adhesions. Chronic inflammatory infiltrations, which are localized in the adventitia, can be found via microscopy. Six of forty-three patients with abdominal aortic aneurysms were found to have an inflammatory aneurysm at operation. In a retrospective study, we examined the sonographic, computed tomographic and angiographic appearance of inflammatory aneurysms. Only with computed tomography can thickening of the aneurysmal wall be demonstrated; angiography does not have this capacity and can only find an inflammatory aneurysm in particular cases.     

Algorithmic approach to CT diagnosis of the abnormal bowel wall.

Computed tomography demonstrates intestinal wall abnormalities that can be analyzed by categorizing attenuation changes in the intestinal wall and transposing morphologic characteristics learned from barium studies. These attenuation patterns include white, gray, water halo sign, fat halo sign, and black. The white pattern represents avid contrast material enhancement that uniformly affects most of the thickened bowel wall. If the bowel wall is enhanced to a degree equal to or greater than that of venous opacification in the same scan, it should be classified in the white attenuation pattern. Common diagnoses with this pattern include idiopathic inflammatory bowel diseases and vascular disorders. The gray pattern is defined as a thickened bowel wall with limited enhancement whose homogeneous attenuation is comparable with that of enhanced muscle. This pattern is used to differentiate between benign and malignant disease, but it is the least specific of the patterns and should be combined with morphologic observations. The water halo sign indicates stratification within a thickened bowel wall that consists of either two or three continuous, symmetrically thickened layers. Common diagnoses with this sign include idiopathic inflammatory bowel diseases, vascular disorders, infectious diseases, and radiation damage. The fat halo sign refers to a three-layered target sign of thickened bowel in which the middle or "submucosal" layer has a fatty attenuation. Common diagnoses with this sign include Crohn disease in the small intestine and idiopathic inflammatory bowel diseases in the colon. Black attenuation is the equivalent of pneumatosis, and this pattern is commonly seen in ischemia, infection, and trauma.     

Sensitivity and specificity of CT in the diagnosis of inflammatory abdominal aortic aneurysms

PURPOSE: The purpose of this study is to assess the diagnostic ability (sensitivity and specificity) of CT in the diagnosis of inflammatory abdominal aortic aneurysm (IAAA) and to quantitatively evaluate its features. METHOD: A retrospective survey of 355 consecutive patients with abdominal aortic aneurysm and iliac artery aneurysm who underwent CT examination and surgical repair yielded 18 patients with operatively confirmed IAAA. The sensitivity, specificity, and diagnostic accuracy of CT were evaluated in this review. Eighteen IAAAs were then analyzed in terms of distribution and degree of perianeurysmal fibrosis as well as time-dependent change of CT values of the aneurysmal wall on contrast-enhanced CT. Complications related to IAAA were also determined. RESULTS: Fifteen of the 18 cases of IAAA could be easily diagnosed on CT prior to surgical repair. Three false-negative and one false-positive case were found. This gives a sensitivity rate of 83.3% for this imaging technique, with specificity and accuracy rates of 99.7 and 93.7%, respectively. Thickening of the aortic wall was noticed mostly in the anterolateral wall of the aneurysm as compared with the posterior wall. The thickness of the perianeurysmal fibrosis correlated neither with the size of aneurysm nor with the inflammatory reaction such as erythrocyte sedimentation rate, C-reactive protein level, and white blood cell count. CT indicated the complications in 7 of 18 patients with IAAA. These included hydronephrosis, aortoenteric fistula, and infected iliac aneurysm. CONCLUSION: CT scan with contrast enhancement was a highly reliable imaging modality for the diagnosis of IAAA.     

CT evaluation of thickened esophageal walls

A study of 200 consecutive chest computed tomographic (CT) examinations revealed thickened esophageal walls (over 3 mm) in 35%. While this is the earliest finding of carcinoma of the esophagus on CT, only half of the cases of thickened walls were due to esophageal carcinoma. Other mediastinal malignancies as well as benign inflammatory, vascular, and fibrotic conditions such as reflux and monilial esophagitis, esophageal varices, and postirradiation scarring were found to cause thickened esophageal walls. Distension with air and intravenous enhancement aid in the optimal evaluation of the esophagus by CT. The thickened esophageal wall is always abnormal, but it is nonspecific, seen in both malignant and nonmalignant conditions.     

Bowel wall thickening in patients with Crohn's disease: CT patterns and correlation with inflammatory activity

AIM: To assess CT patterns of bowel wall thickening in patients with Crohn's disease and to correlate these patterns with inflammatory activity. MATERIALS AND METHODS: We conducted a retrospective review of 58 helical abdominal CT scans of 53 patients with pathologically proven Crohn's disease. CT patterns of thickened bowel wall were divided into four types based on patterns of mural stratification and enhancement: type A, multilayered mural stratification; type B, two layers with strong mucosal enhancement and prominent low-density submucosa; type C, two layers without strong mucosal enhancement; and type D, homogeneous enhancement. We evaluated CT findings of the bowel and adjacent structures. We also reviewed pathologic features and clinical data to determine inflammatory activity. RESULTS: Fifty-five (95%) of 58 CT examinations showed bowel wall thickening. Of these 55 CT scans, type A pattern was found in 33 (60%), type B in 10 (18%), type C in five (9%), and type D in seven (13%). CT scans with type A showed significantly more wall thickening than those with either type C or type D. Histology revealed 43 cases with active disease and 12 with quiescent appearance. Thirty of 33 CT scans with type A and all 10 with type B were classified as acute disease, and three of five with type C and six of seven with type D as quiescent. CONCLUSION: In patients with Crohn's disease, CT patterns of bowel wall thickening correlated with inflammatory activity. Thickened bowel wall with layering enhancement is predictive of acute disease, and that of homogeneous enhancement suggests quiescence.     

Mycotic aneurysms of the aorta: radiologic features

Four patients with a total of six mycotic aneurysms of the aorta were examined with computed tomography (CT) after intravenous contrast material enhancement, and with abdominal or thoracic aortography. In the three patients with mycotic aneurysms involving the abdominal aorta, CT scans showed a vascular paraaortic structure without calcified walls adjacent to a nondilated aorta, and a large non-contrast-enhanced retroperitoneal mass representing inflammatory tissue and blood from a contained aortic rupture. A CT scan of one aneurysm of the thoracic aorta demonstrated an enhanced saccular mass originating from the aorta without paraspinal component. In three of four patients, the CT findings were corroborated by aortographic evidence of an eccentric aneurysmal sac in an atypical location for atheromatous disease. In four patients with clinical manifestations suggesting mycotic aneurysm of the aorta, a combination of CT and angiographic imaging provided accurate diagnostic information for planning adequate and early surgical treatment.     

Impending rupture of nonaneurysmal bacterial aortitis: CT diagnosis

The CT appearance of mycotic abdominal aortic aneurysms leading to eventual rupture has been well described. On the other hand, ruptured nonaneurysmal bacterial aortitis has not been demonstrated in the CT literature. We present two cases with subsequent rupture documented on CT. The characteristic findings of periaortic density and adjacent gas collection should suggest the diagnosis of acute aortic infection. This may herald impending rupture, even in the absence of aneurysmal dilatation, and should direct therapy accordingly.     

Inflammatory aneurysms of the abdominal aorta: US and CT characteristics

The authors report their experience with US and CT in 31 cases of inflammatory aneurysms out of a study population of 200 patients with abdominal aortic aneurysms. The work started with a case that had not been diagnosed at US, either due to the operator's poor knowledge of this pathologic condition or because of improper examination technique. The authors stress the importance of a high-frequency probe and proper gain settings which are often necessary for a good visualization of the anterior aortic wall. The correct diagnosis of the inflammatory nature of the aneurysm has been assessed by US ever since, in all cases except for very obese and meteoric patients. In our series, US diagnostic accuracy was 78%, versus 33% reported in literature. US was not accurate in evaluating adjacent structures involvement within fibrous tissues (ureteral narrowing, caval narrowing)--which CT did. Neither US nor CT exhibited reliable diagnostic accuracy in demonstrating enteric involvement within fibrous tissues.     

Aortic arch aneurysms: treatment with extraanatomical bypass and endovascular stent-grafting

Endovascular repair of thoracic aortic aneurysms is emerging as an attractive alternative to surgical graft replacement. However, patients with aortic arch aneurysms are often excluded from the target of endovascular repair because of lack of suitable landing zones, especially at the proximal ones. In this paper we describe our method for treating patients with aortic arch aneurysms using a combination of extraanatomical bypass surgery and endovascular stent-grafting.     

'Inflammatory' abdominal aortic aneurysms

The term 'inflammatory aneurysm' is used to describe a variant of atherosclerotic abdominal aortic aneurysms in which the wall of the aneurysm is unusually thick and surrounded by extensive fibrosis and adhesions. Repair of these aneurysms is associated with a higher mortality and morbidity than repair of those which are non-inflammatory, so that diagnosis prior to surgery is desirable. The use of computed tomography (CT) and ultrasound in this differentiation is discussed. The correct diagnosis was made in 16 out of 17 by CT, but in only three of nine cases who had ultrasound scans.