Sealed rupture of abdominal aortic aneurysms: CT features in 6 patients and a review of the literature

A case of chronic contained rupture of abdominal aortic aneurysm mimicking a retroperitoneal tumor

Chronic contained rupture of abdominal aortic aneurysm (CCR-AAA) is a rare subtype of abdominal aortic rupture that can mimic other retroperitoneal lesions. We report a case of CCR-AAA in a man in his sixties who presented with a 10-month history of right low back pain and weight loss. Contrast-enhanced computed tomography (CT) revealed a lobulated retroperitoneal mass around the abdominal aorta, initially misdiagnosed as a possible hemorrhagic retroperitoneal tumor. Despite multiple imaging studies including CT, magnetic resonance imaging (MRI), and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET)/CT, as well as a CT-guided biopsy, the correct diagnosis remained elusive for 34 months. Key findings included subtle aortic wall irregularity on CT, high signal intensity on T1-weighted MRI suggesting hematoma, peripheral FDG uptake on PET/CT, and histological findings of biopsy tissue consistent with organizing hematoma. Surgery confirmed the diagnosis, revealing an organized hematoma with a defect in the right wall of the abdominal aortic aneurysm. This case demonstrates that CCR-AAA can present with atypical radiological features, potentially leading to misdiagnosis. When encountering a para-aortic mass with a hemorrhagic component, careful observation of the AAA morphology and aortic wall contour is crucial for an accurate diagnosis of CCR-AAA.

Chronic contained ruptured abdominal aortic aneurysm with a rare presentation of lower limb neuropathic claudication: a report of two cases

A vertebral body erosion that takes place due to a chronic contained rupture of an abdominal aortic aneurysm is an especially rare vascular pathology that comprises less than 5% of all causes of vertebral body erosion. Chronic contained rupture of an abdominal aortic aneurysms are primarily observed in hemodynamically stable patients whose chief complaint is lower limb neuropathic pain. This entity is extremely misleading and this results in delayed management of those patients increasing the morbidity and mortality rates.

CASE PRESENTATION

We present the two cases of 62-year-old and 65-year-old males. Preoperative radiology for each patient showed an infrarenal aortic aneurysm with a retroperitoneal hematoma in contact with the lumbar vertebral bodies and psoas muscle. The draped aorta sign was evident in both cases.

CLINICAL DISCUSSION

A curative surgical intervention was accomplished for both patients, respectively. This was achieved through the removal of the existing hematomas that were compressing the vertebrae in addition to the complete isolation and resection of the respective abdominal aortic aneurysms along with thorough reconstruction of the aortoiliac spindles with patent synthetic grafts to ensure the patency of the preexisting vascular axis.

CONCLUSION

A contained rupture of an abdominal aortic aneurysm is a rare occurring vascular pathology that manifests with nonspecific symptoms, such as femoral neuropathy and lower back pain proportionate to the degree of the level of erosion of the affected lumbar vertebrae. This will increase the possibility of misdiagnosis and delays in treatment. Such a life-threatening vascular emergency should be timely detected and treated to avoid its complications and patient mortality.

Chronic Ruptured Abdominal Aortic Aneurysm

Chronic rupture of Abdominal Aortic Aneurysm is a rare presentation although AAA and its frank rupture is well known phenomenon. Chronic rupture of AAA can be misdiagnosed due to non-specific presentation and absence of haemorrhagic shock. This case report discusses the presentation scenarios as well radiologic findings which may help diagnose a Chronic Ruptured AAA (CR-AAA) and will be helpful in prompt recognition and early management of the situation.

Chronic abdominal aortic rupture mimicking femoral neuropathy

Chronic-contained rupture of an aortic aneurysm is a rare subset of ruptured aneurysms. The presentation is unusual, and the diagnosis is frequently delayed. Here, we describe a case of contained rupture of abdominal aortic aneurysm that presented with signs and symptoms of femoral neuropathy. Clinical and radiological findings were initially misinterpreted. The correct diagnosis was formulated belatedly, causing a progressively increased risk of fatal events. Surgical aortic repair was performed and the postoperative course was uneventful. In conclusion, in the presence of a retroperitoneal mass, a diagnosis of chronic-contained rupture of an abdominal aortic aneurysm should be considered.

[Summary of the S3 guideline on abdominal aortic aneurysm from an anesthesiological perspective]

The current article is a summary of the 2018 revised S3 guideline on screening, diagnosis, therapy, and follow-up of the abdominal aortic aneurysm (AAA) from an anesthesiological point of view. It is the only interdisciplinary guideline that describes in particular the perioperative anesthesiological and intensive care management.

Signs of impending rupture in abdominal aortic and iliac artery aneurysms by computed tomography: Outcomes in 41 patients

OBJECTIVES

This study aimed to determine the prevalence of signs of impending rupture (SIR) in asymptomatic patients with abdominal aortic and iliac artery aneurysms, and to evaluate whether these signs were associated with rupture in asymptomatic patients.

METHODS

This was a retrospective study of patients with abdominal aortic and iliac artery aneurysms identified on computed tomography (CT) over a 10-year period in a single center. The CT scans were reviewed by two reviewers, and patients with SIR were assigned to one of three groups: (1) early symptomatic (ES), (2) late symptomatic (LS), and (3) always asymptomatic (AA). The four main SIR described in the literature were investigated: 1) crescent sign, 2) focal wall discontinuity of circumferential calcifications, 3) aortic bulges or blebs, and 4) aortic draping.

RESULTS

From a total of 759 aortic and iliac aneurysm reports on 2226 CT scans, we identified 41 patients with at least one SIR, and a prevalence of 4.14% in asymptomatic patients. Focal wall discontinuity of circumferential calcifications was the most common sign, and it was present in 46.3% of these patients (19/41); among these, 26 were repaired (ES: 9, LS: 2, AA: 15). Eleven asymptomatic patients underwent follow-up CT. The aneurysm increased in size in 6 of the 11 (54.5%) patients, and three ruptured (all with discontinuity of calcifications), one of which had no increase in diameter.

CONCLUSIONS

The presence of focal wall discontinuity of circumferential calcifications was the most common SIR. There was a prevalence of all signs in less than 5% of asymptomatic patients. In unrepaired patients, the signs could be observed on follow-up CT scans with an increase in aneurysm size, indicating that the presence of SIR alone in the absence of other clinical factors or aneurysm characteristics is an insufficient indication for surgery.

Contained Rupture of a Thoracic Aortic Aneurysm Mimicking a Malignant Tumor: a Case Report

An 81-year-old man underwent F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) to evaluate a mediastinal mass, which was discovered during the investigation for hemoptysis. The periphery of the mass abutting the aortic arch demonstrated heterogeneously increased FDG uptake, whereas most of the central portion of the mass was photopenic. The mass turned out to be an atheromatous organizing hematoma associated with contained aortic rupture.

Multidetector Computed Tomography in Traumatic and Nontraumatic Aortic Emergencies: Emphasis on Acute Aortic Syndromes

Aortic emergencies comprise of a list of conditions which are uncommon but are potentially fatal. Prognosis is usually determined by emergent diagnosis and treatment and hence radiology plays a key role in patient management. In this article, we aim to review the various causes of aortic emergencies and the relevant imaging findings placing special emphasis on acute aortic syndromes.

Acute non-traumatic disease of the abdominal aorta

Acute pathology in the abdominal aorta is associated with significant morbidity and mortality. The most feared complication of abdominal aortic disease is acute rupture in the setting of atherosclerotic abdominal aortic aneurysm. Although frank rupture often is easily diagnosed on CT, other findings such as a hyperattenuating crescent, discontinuous intimal calcium, and draping of the aorta are subtle signs of aneurysm instability. A true aneurysm should be distinguished from a rapidly growing, saccular pseudoaneurysm in the setting of infectious aortitis, as treatment strategy differs. Acute aortic syndrome involving the abdominal aorta, such as dissection and intramural hematoma, often is an extension of thoracic aortic disease, whereas penetrating atherosclerotic ulcers occasionally involve only the abdominal aorta. The goal of treating acute aortic pathology is to repair and prevent rupture, as well as restore and maintain perfusion of the lower extremities, kidneys, and mesentery. However, both open and endovascular repair of the abdominal aorta may become acutely complicated, resulting in compromise of these goals. Examples include aortoenteric fistula, endoleak, anastomotic pseudoaneurysm, graft infection, and thrombosis or kinking of a stent graft resulting in ischemia of the limbs and mesentery.

Clues to vascular disorders at non-contrast CT of the chest, abdomen, and pelvis

Non-contrast chest CT scans are commonly performed while CT scans of the abdomen and pelvis are performed in a select subset of patients; those with limited renal function, an allergy to iodinated contrast, in the setting of suspected renal calculus, retroperitoneal hematoma, common duct calculus, abdominal aortic aneurysm with or without rupture, and in patients undergoing a PET-CT scan. In the absence of intravenous contrast, vascular structures may prove challenging to evaluate, yet their assessment is an important component of every non-contrast CT examination. We describe the key imaging features of both arterial and venous pathology, and review clues and common associated non-vascular findings, which can help the radiologist identify vascular disorders at non-contrast CT. Briefly, alternative imaging options are discussed.

Extensive Erosion of Vertebral Bodies Due to a Chronic Contained Ruptured Abdominal Aortic Aneurysm

This report describes a case of chronically ruptured abdominal aortic aneurysm contained within the lumbar vertebral bodies that presented with dull abdominal pain. Sudden, massive hemorrhage is an uncommon, yet well-known complication of an untreated abdominal aortic aneurysm. In addition, misleading clinical and radiological findings present difficult diagnostic challenges in such cases. This report emphasizes the findings obtained with multidetector computed tomography and delineates the differentiation of this condition from similar pathologies.

Unstable abdominal aortic aneurysms: a review of MDCT imaging features

Abdominal aortic aneurysms are commonly encountered during abdominal CT imaging, and size-based parameters for surgical or endovascular repair are well established. Aneurysms greater than 5 cm in diameter are recognized as representing an increased rupture risk and meriting intervention. Increasingly, additional interest has been generated in recognizing imaging features which may herald instability and portend a higher chance for potentially catastrophic rupture. This article will review and illustrate such signs, including hyperattenuation of mural thrombus, rapid expansion, low thrombus to lumen ratio, intimal calcification disruption, posterior mural draping, and saccular outpouching. Other features of complicated abdominal aneurysms including perianeurysmal inflammation, aortocaval and aortoenteric fistula formation will also be addressed. Heightened awareness of these features and their prognostic implications, as well as timely communication with the clinical service, is critical for the interpreting radiologist.

Abdominal aortic aneurysms revisited: MDCT with multiplanar reconstructions for identifying indicators of instability in the pre- and postoperative patient

Rupture of an abdominal aortic aneurysm is commonly a fatal event. Multidetector computed tomographic (CT) signs of frank aortic rupture are usually readily apparent and widely understood. However, diagnosing an impending aortic rupture on the basis of imaging findings can prove more difficult. CT is the primary modality used for serial imaging in patients with aortic aneurysm and may show findings indicative of aortic instability. Therefore, it is critical that radiologists be familiar with the CT findings of aortic instability to avert the potential complications of hemorrhage, end organ or limb ischemia, and death. Various preoperative CT indicators have been previously described in both research investigations and review articles. A large baseline aneurysm size and a rapid increase in size over time are associated with a higher risk for rupture. The importance of obtaining accurate measurements with multiplanar reconstructions and the role of new semiautomated tools for obtaining accurate, reproducible measurements are discussed. Additional CT findings that reflect aortic aneurysm instability include luminal expansion with lysis of thrombus, intramural hemorrhage (ie, the crescent sign), periaortic hemorrhage, a penetrating atherosclerotic ulcer, and contained rupture (ie, the draped aorta sign). After open or endovascular aneurysm repair, CT is routinely used to monitor for graft complications. In this setting, radiologists should understand that the presence of an endoluminal stent or surgical graft does not preclude aortic rupture. Online supplemental material is available for this article.

Chronic Contained Abdominal Aortic Aneurysm Rupture Mimicking Vertebral Spondylodiscitis: A Case Report

A 63-year-old Caucasian male presented with a 4-month history of low back pain associated with bilateral intermittent claudication. A contrast enhanced CT scan demonstrated a 4 cm abdominal aortic aneurysm (AAA), along with severe bilateral aorto-iliac disease, a right psoas collection, and extensive vertebral erosion. An MRI of the lumbar spine suggested spondylodiscitis at L4-L5. After an unsuccessful and prolonged course of antibiotics, a decision was ultimately made to repair the aneurysm and bypass the aorto-iliac disease. Intra-operatively, a chronic contained rupture (CCR) involving the posterior aortic wall was encountered and repaired with an aorto-bifemoral bypass graft.

Rupture signs on computed tomography, treatment, and outcome of abdominal aortic aneurysms

OBJECTIVES

Abdominal aortic aneurysm (AAA) rupture has a high mortality rate. Although the diagnosis of a ruptured AAA is usually straightforward, detection of impending rupture signs can be more challenging. Early diagnosis of impending AAA rupture can be lifesaving. Furthermore, differentiating between impending and complete rupture has important repercussions on patient management and prognosis. The purpose of this article is to classify and illustrate the entire spectrum of AAA rupture signs and to review current treatment options for ruptured AAAs.

METHODS

Using medical illustrations supplemented with computed tomography (CT), this essay showcases the various signs of impending rupture and ruptured AAAs. Endovascular aneurysm repair (EVAR) and open surgical repair are also discussed as treatment options for ruptured AAAs.

RESULTS

CT imaging findings of ruptured AAAs can be categorised according to location: intramural, luminal, and extraluminal. Intramural signs generally indicate impending AAA rupture, whereas luminal and extraluminal signs imply complete rupture. EVAR has emerged as an alternative and possibly less morbid method to treat ruptured AAAs.

CONCLUSIONS

AAA rupture occurs at the end of a continuum of growth and wall weakening. This review describes the CT imaging findings that may help identify impending rupture prior to complete rupture.

TEACHING POINTS

• AAA rupture occurs at the end of a continuum of growth and wall weakening. • Intramural imaging findings indicate impending AAA rupture. • Luminal and extraluminal imaging findings imply complete AAA rupture. • Some imaging findings are not specific to AAA ruptures and can be seen in other pathologies. • EVAR has emerged as an alternative and possibly less morbid method of treating ruptured AAAs.

Multidetector computed tomography angiography findings of chronic-contained thoracoabdominal aortic aneurysm rupture with severe thoracal vertebral body erosion

Chronic-contained aortic aneurysm rupture with vertebral erosion is a rare entity with fatal complications. Multidetector computed tomography (CT) angiography is an important diagnostic method for the evaluation of the aortic aneurysms, their complications, and also the relationship between aneurysm and branching vessels and adjacent structures. We present the multidetector CT angiography findings of a 62-year-old patient with chronic-contained thoracoabdominal aortic aneurysm rupture causing severe vertebral body erosion.

ACR Appropriateness Criteria® pulsatile abdominal mass, suspected abdominal aortic aneurysm

Clinical palpation of a pulsating abdominal mass alerts the clinician to the presence of a possible abdominal aortic aneurysm (AAA). Generally an arterial aneurysm is defined as a localized arterial dilatation ≥50% greater than the normal diameter. Imaging studies are important in diagnosing the cause of a pulsatile abdominal mass and, if an AAA is found, in determining its size and involvement of abdominal branches. Ultrasound (US) is the initial imaging modality of choice when a pulsatile abdominal mass is present. Noncontrast computed tomography (CT) may be substituted in patients for whom US is not suitable. When aneurysms have reached the size threshold for intervention or are clinically symptomatic, contrast-enhanced multidetector CT angiography (CTA) is the best diagnostic and preintervention planning study, accurately delineating the location, size, and extent of aneurysm and the involvement of branch vessels. Magnetic resonance angiography (MRA) may be substituted if CT cannot be performed. Catheter arteriography has some utility in patients with significant contraindications to both CTA and MRA. The American College of Radiology Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Repetitive contained rupture of an infected abdominal aortic aneurysm with concomitant vertebral erosion

We describe a rare case of surgical treatment for a repeated contained rupture of an infected abdominal aortic aneurysm (AAA) with concomitant vertebral erosion. A 59-year-old man presented to a nearby hospital with abdominal pain and fever. On admission, computed tomography (CT) scan revealed a contained rupture of AAA, but the patient declined the offer of surgical therapy. Thereafter, the retroperitoneal hematoma gradually reduced in size. The third and fourth lumbar vertebrae were eroded on the CT scan 12 months after the appearance of the first symptom. However, 21 months after the first symptom, he suffered severe lumbago and was diagnosed with recurrence of contained AAA rupture and vertebral body destruction. He underwent debridement of eroded vertebrae and in situ graft replacement of AAA with omentum flap wrapping. Intraoperative microscopic examination of the hematoma revealed gram-positive Streptococcus. His postoperative course was uneventful, and CT 12 months after surgery did not reveal further deterioration of vertebral erosion or fluid accumulation. Repetitive contained AAA rupture may be another entity in contrast to chronic contained AAA rupture. Vertebral erosion could be associated with infection rather than mass effects of the contained hematoma. Surgical treatment is indicated to prevent life-threatening re-rupture and severe spinal instability.