The association of aorto-iliac aneurysms with ureteral obstruction

Aorto-iliac aneurysms may entrap the ureters in perianeurysmal fibrosis, causing medial ureteral deviation and/or obstruction. The latter has been described only in male patients; a further 5 cases due to iliac and 3 to aortic aneurysm are reported. The radiologic picture resembles retroperitoneal fibrosis; the correct diagnosis may be suggested when ureteral tethering or narrowing lies near arterial calcification. Sonography is usually the most appropriate investigation to confirm the diagnosis. When sonography shows an aortic aneurysm, the kidneys should be scanned to rule out hydronephrosis. Similarly, films of the kidneys should be obtained when an abdominal aneurysm is demonstrated by aortography.     

Ureteral leak after an abdominal aortic aneurysm repair: case report

Iatrogenic ureteral injuries are an infrequent complication of vascular reconstructive surgery, and if they are not suspected at the time of surgery the diagnosis is usually delayed. Diagnosing these injuries may be challenging, since patients usually show signs and symptoms appropriate to a normal postoperative course and usually do not develop hematuria or renal dysfunction. In the proper clinical setting, a fluid collection adjacent to the ureter on cross-sectional imaging studies should alert the emergency radiologist to the possibility of ureteral injury. A high clinical suspicion would allow earlier diagnosis and treatment, potentially reducing the morbidity and mortality associated with a delay in diagnosis. We present a case of a ureteral leak diagnosed 1 week after an abdominal aortic aneurysm repair. A fluid collection seen adjacent to the ureter on contrast-enhanced CT prompted the radiologist to obtain delayed images that demonstrated urinary extravasation. Electronic Publication     

Posterior "nutcracker" phenomenon: hemodynamic relevant aorto-retroaortal renal vein fistula leading to fatal right heart failure

A rare complication of an aneurysm of the abdominal aorta is the so-called "posterior nutcracker phenomenon", which describes compression of a retroaortal renal vein between the abdominal aorta and the vertebral column. The clinical presentation is flank pain and hematuria, which are usually caused by a renal (respectively ureteral) calculus or neoplasia. Another rare differential diagnosis for these very common clinical symptoms is an aorto-left renal vein fistula (ALRVF), which is a spontaneous vascular fistula, usually also associated with an aortic aneurysm, infrequently a result of abdominal trauma.     

Multi-modality molecular imaging of aortic aneurysms

Aneurysms of the thoracic and abdominal aorta are common and can be associated with significant morbidity and mortality when complications, including dissection, rupture, or thrombosis, occur. Current approaches to diagnosis and risk stratification rely on measurements of aneurysm size and rate of growth, often using various imaging modalities, which may be suboptimal in identifying patients at the highest and lowest risk of complications. Targeting the biological processes underlying aneurysm formation and expansion with molecular imaging offers an exciting opportunity to characterize aortic aneurysms beyond size and address current gaps in our approach to diagnosis and treatment. In this review, we summarize the epidemiology and biology of aortic aneurysms and highlight the role of molecular imaging in furthering our understanding of aneurysm pathogenesis and its potential future role in guiding management.

     

Ureteral obstruction resulting from vascular prosthetic graft surgery.

Four cases of ureteral obstruction are described which were primarily due to compression from an overlying vascular graft and retroperitoneal fibrosis. Infection may also be causal. Excretory urography should be performed routinely after vascular prosthetic surgery to permit early diagnosis of this complication. Ultrasonography may also be helpful in certain cases.     

Contrast-enhanced sonography for diagnosis of ruptured abdominal aortic aneurysm

OBJECTIVE: We describe the contrast-specific sonography features of ruptured abdominal aortic aneurysm, and we hypothesize that this technique would be useful for emergency imaging of patients with suspected aneurysm rupture. CONCLUSION: We used contrast-specific sonography to assess eight patients with ruptured abdominal aortic aneurysm. Five of these cases were correlated with CT findings. We found that contrast-enhanced sonography can reveal features specific for ruptured aortic aneurysm without causing a significant delay in surgery. This technique may be as effective as CT but may allow a more rapid and noninvasive diagnosis, especially when sonography can be performed bedside.     

Unilateral absence of ventilation and perfusion due to thoracic aortic aneurysm

An elderly man presented with progressive atelectasis of the left lung, a mediastinal mass, and dilatation of the thoracic aorta. Ventilation and perfusion radionuclide lung scans revealed the complete absence of ventilation in the left lung and near-complete absence of perfusion. Evaluation by MRI and angiography showed an obstructing mediastinal "mass" to be a saccular aortic aneurysm. A thoracic aortic aneurysm should be a consideration in the differential diagnosis for unilateral decrease or absence of ventilation and perfusion with a history or findings of mediastinal mass or aneurysm.     

CT of aortic aneurysms: the distinction between mural and thrombus calcification

Aortic calcification, either mural or thrombus, is a common finding in patients with abdominal aortic aneurysms. Differentiating between the two sites of calcification is necessary in order to avoid confusing simple thrombus calcification with displaced calcified intima in aortic dissection. The CT scans of 145 cases of abdominal aortic aneurysm and seven cases of abdominal aortic aneurysm with dissection were analyzed with respect to the location of the calcification: mural only or mural and thrombus. Mural calcification was seen in all 152 patients with aneurysms whereas thrombus calcification was identified in only 33 (24%) of the 136 patients with thrombus. Displaced intimal calcification caused by aortic dissection can either appear similar to or, at times, be indistinguishable from thrombus calcification. Thrombus calcification was present in four (57%) of the seven patients with abdominal aortic aneurysms and dissection. To avoid the possibility of a false-positive diagnosis of aortic dissection in patients with abdominal aortic aneurysm, other signs of aortic dissection should be sought such as separation of the true and false lumina by an intimal flap.     

Ruptured thoracic aneurysm: unusual manifestation and early diagnosis using CT

Rupture of a thoracic aortic aneurysm across the posterior mediastinum into the right side of the chest is rare. The diagnosis may be delayed by the absence of expected findings in the left side of the chest. We recently encountered two patients with thoracic aneurysm rupture who came to medical attention initially because of right-sided pleural and/or extrapleural hematomas, which were accurately diagnosed preoperatively on the basis of computed tomography (CT) findings. Aortography, performed in one patient, added no useful information. Because CT accurately identifies the presence of pleural or extrapleural blood, as well as the underlying aneurysm or dissection, CT should be the first examination performed in cases of suspected thoracic aneurysm rupture.     

Inflammatory aneurysm of aorta: development documented by computed tomography

Aortic aneurysmal disease appears to be the central focus of the inflammatory process resulting in inflammatory aneurysm formation. Some authors believe that inflammatory aortic aneurysm disease is a distinct clinicopathologic entity; however, others have included it with retroperitoneal fibrosis. The histologic features of inflammatory aneurysm suggest an immunologic basis for the lesion, with the atherosclerotic aorta as a possible source of the allergen.     

Stenosing hemorrhagic ureteritis in a child with Henoch-Sch?nlein purpura: CT appearance

Henoch-Sch?nlein purpura is rarely considered in the differential diagnosis of ureteral obstruction in children. Renal ultrasound and intravenous urography may reveal hydroureteronephrosis but usually fail to yield a specific diagnosis. In this child CT differentiated between an intrinsic ureteral stenosis (hemorrhagic ureteritis) and an extrinsic ureteral stenosis (retroperitoneal fibrosis), two rare complications of Henoch-Sch?nlein purpura. The CT findings of hemorrhagic ureteritis are described.     

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.     

Retroperitoneal fibrosis: use of CT in distinguishing among possible causes

Retroperitoneal fibrosis (RF) often presents with characteristic clinical and urographic findings that suggest the diagnosis. However, malignant adenopathy may mimic this appearance. CT examinations of 10 patients with medial deviation of the ureters suggesting retroperitoneal fibrosis were reviewed. Six had idiopathic RF, two had perianeurysmal fibrosis, and two had malignant retroperitoneal adenopathy. The CT findings in idiopathic RF included a homogeneous mass enveloping the ureters, aorta, and inferior vena cava. The aortic aneurysm was easily seen in both patients with perianeurysmal fibrosis. In one of the two patients with malignant retroperitoneal adenopathy, the CT findings mimicked idiopathic RF. In the other patient, the nodes involved with metastatic melanoma caused significant anterior displacement of the aorta and inferior vena cava. This marked anterior displacement of the great vessels is not seen in idiopathic RF, and may be useful in differentiating these entities.     

Radiologic features and anatomic basis of atypical clinical presentations of ruptured abdominal aortic aneurysms

Ruptured abdominal aortic aneurysms (AAAs) occasionally manifest with atypical clinical presentations and can be initially misdiagnosed. Symptoms are attributable either to local mass effect from the aneurysm or a contained rupture, or to the particular cavity or anatomic space into which an aneurysm bleeds. Radiologic studies obtained in this patient population often will demonstrate signs of the ruptured AAA, and these signs should be actively searched for when a ruptured AAA can be in the differential diagnosis. Emergent computed tomographic examination is indicated to confirm any clinical or radiologic suspicion of a ruptured abdominal aortic aneurysm, provided that the patient remains hemodynamically stable. The anatomic basis for a ruptured AAA presenting clinically as renal colic is discussed and illustrated, and the spectrum of clinical presentations of ruptured AAAs is reviewed.     

The endoleak problem in endoluminal therapy

Endovascular treatment of aortic aneurysms with stent grafts was performed increasingly in recent years. The most frequent complication after endovascular therapy of aortic aneurysms is an endoleak. In case of a persistent endoleak, diameter of the aneurysm is increasing with a high risk of aneurysm ruptur. Diagnostic tools are spiral computed tomography and angiography. Spiral computed tomography is the most sensitive method for the diagnosis of an endoleak ad should be performed with a biphasic acquisition. In- and outflow of sidebranches can be identified correctly with selective angiography in 86%. Perigraft endoleaks should be treated in any case. Patent side branches generally are observed over a period of 6 months. After 6 months approximately half of these endoleaks are thrombosed. Is there an increasing of the diameter of the aneurysm or any changing in the morphology of the aneurysm there is an indication for embolisation of these sidebranches of the aneurysmal sac. Preinterventional embolisation of patent sidebranches is under discussion. Type I endoleaks can be managed by additional stent-graft implantation or coil embolisation. In case of type II endoleaks in- ad outflow vessels should be embolised with coils. Therapy of type III endoleak is performed mostly by additional stent-graft placement. The total incidence of secondary interventions in the Eurostar-study was nearly 10% per year.     

The problem with endoleakage in endoluminal therapy

Endovascular treatment of aortic aneurysms with stent grafts was performed increasingly in recent years. The most frequent complication after endovascular therapy of aortic aneurysms is an endoleak. In case of a persistent endoleak, diameter of the aneurysm is increasing with a high risk of aneurysm rupture. Diagnostic tools are spiral computed tomography and angiography. Spiral computed tomography is the most sensitive method for the diagnosis of an endoleak ad should be performed with a biphasic acquisition. In- and outflow of sidebranches can be identified correctly with selective angiography in 86%. Perigraft endoleaks should be treated in any case. Patent side branches generally are observed over a period of 6 months. After 6 months approximately half of these endoleaks are thrombosed. Is there an increasing of the diameter of the aneurysm or any changing in the morphology of the aneurysm there is an indication for embolisation of these sidebranches of the aneurysmal sac. Preinterventional embolisation of patent sidebranches is under discussion. Type I endoleaks can be managed by additional stent-graft implantation or coil embolisation. In case of type II endoleaks in- ad outflow vessles should be embolised with coils. Therapy of type III endoleak is performed mostly by additional stent-graft placement. The total incidence of secondary interventions in the Eurostar-study was nearly 10% per year.     

Infected aortic aneurysms: CT appearance

Three patients with infected (mycotic) aortic aneurysms were diagnosed primarily by CT. In two patients findings included the presence of a saccular aneurysm with an irregular lumen, perianeurysmal fluid, gas and/or hematoma, osteomyelitis in adjacent vertebral bodies, and disruption of intimal calcification. In one patient with sepsis there was rapid development of an aortic aneurysm. Computed tomography is of substantial benefit in the identification and characterization of infected aortic aneurysms. Certain features may strongly suggest the diagnosis without use of aortography.     

主动脉窦瘤破裂彩色多普勒超声心动图的诊断

目的：分析主动脉窦瘤（RASA）的彩色多普勒超声心动图（CDE）图像特点,评价多普勒超声心动图诊断的准确性。方法：对26例诊断为RASA的超声心动图进行分析,并与其心血管造影及手术结果进行对比。结果：26例患者中超声心动图诊断准确25例（占96.2%）,误诊1例（占3.8%）,CDE表现为主动脉窦部的局限性向外突起,突起大小、形态不一,且不规则,窦瘤可随心动周期摆动,破口大多位于窦瘤的顶部,破口处可见彩色分流束,分流从顶部破口流入邻近心腔,分流持续整个心动周期。结论：CDE可较准确的诊断主动脉窦瘤破裂的类型,有利于类似畸形的鉴别,并为采取的治疗方式提供依据。     

Computed tomography of life-threatening complications of abdominal aortic aneurysm. The disrupted aortic wall

A localized disruption of the conspicuity of the wall of the aorta was noted on intravenous contrast-enhanced computed tomography (CT) scans of ten patients with ruptured abdominal aortic aneurysm (n = 6) or aortoenteric fistula (n = 4). Subsequently, we reviewed 84 scans of patients with uncomplicated aneurysm (n = 70) or aneurysm graft repair (n = 14) to determine if a disrupted wall has diagnostic implications. In this control group, the wall of the aneurysm was conspicuous throughout in 95% of 64 patients who received iodinated contrast material intravenously and in 55% of 20 patients who did not. In the proper clinical setting, CT scans performed with intravenous administration of iodinated contrast material can provide direct evidence of disruption of the wall of an abdominal aortic aneurysm. In selected cases, this may be important for the diagnosis of rupture. Disrupted conspicuity of the wall, in combination with effacement of the fat plane between an aneurysm and the juxtaposed intestine, increases the accuracy of CT for the diagnosis of aortoenteric fistula.     

Infected aneurysm of abdominal aorta: early CT finding

Infected abdominal aortic aneurysm is an uncommon but life-threatening disease, especially in case of salmonella infection. Early CT findings should be well known in order to allow immediate diagnosis and accurate management. The authors present an early CT finding of a salmonella infected aneurysm of abdominal aorta in an HIV-infected patient. This pattern consists in a slight-enhancing focal densification of periaortic soft-tissue, while aorta remains of normal size. Within two weeks, infection progressed to the constitution of an infected aneurysm. This CT finding seems to be initial to previously described signs.