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Magnetic Resonance Angiography Chapter | 19 213
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(A) (B)
FIGURE 19.6 Abdominal aorta atherosclerosis associated with aortic wall irregularities and atherosclerotic plaque. (A) Coronal contrast-enhanced
magnetic resonance angiography (MRA) maximum intensity projection (MIP) image. (B) Axial view contrast-enhanced MRA MIP image.
FIGURE 19.7 Aortic coarctation with presence of collateral vessels. Oblique sagittal contrast-enhanced magnetic resonance angiography (MRA) maximum intensity projection (MIP) image of the thoracic aorta showing a large number of collateral vessels.
FOLLOW-UP EXAMINATIONS
Based on its high reproducibility, MRI is excellent for the follow-up of aortic disorders that generally request serial checkup
exams lifelong. Patients with endoprostheses can also be evaluated, with the care that the first check should be performed
at 4 weeks of treatment to prevent movement of the stent/endoprosthesis, which must also be made of material that does
not interfere with MRI sequences. Nitinol stents do not distort the MR signal and are well depicted in T1- and T2-weighted
images.
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CONCLUSIONS
Nowadays, MRA technique has been accepted as an excellent noninvasive diagnostic imaging modality for the assessment
of the aorta, providing decisive information about vessel diameters, wall features, and adjacent structures. With the latest generation high-field MRI systems, this technique plays an important role in specific situations where CTA or digital
angiography is contraindicated or nonavailable. Noncontrast 3D time-of-flight MRA is an option in patients with absolute
contraindications to iodine or gadolinium-based contrast (e.g., kidney failure). MRA of the aorta is useful for diagnosis,
treatment planning in a follow-up study in chronic aortic diseases, and postsurgical or postinterventional scenarios.
REFERENCES
[1] Erbel R, Alfonso F, Boileau C, et al. Task force on aortic dissection, European Society of Cardiology. Diagnosis and management of aortic dissec-
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[2] Prince MR. Gadolinium enhanced MR aortography. Radiology 1994;191:155–64.
[3] Glockner JF. Three-dimensional gadolinium-enhanced MR angiography: applications for abdominal imaging. Radiographics 2001;21:357–70.
[4] Hartnell GG. Imaging of aortic aneurysms and dissection: CT and MRI. J Thorac Imaging 2001;16:35–46.
[5] Krishnam MS, Tomasian A, Deshpande V, et al. Noncontrast 3D steady-state free-precession magnetic resonance angiography of the whole chest
using nonselective radiofrequency excitation over a large field of view: comparison with single-phase 3D contrast-enhanced magnetic resonance
angiography. Invest Radiol 2008;43(6):411–20.
[6] Krishnam MS, Tomasian A, Malik S, Desphande V, Laub G, Ruehm SG. Image quality and diagnostic accuracy of unenhanced SSFP MR angiogra-
phy compared with conventional contrast-enhanced MR angiography for the assessment of thoracic aortic diseases. Eur Radiol 2010;20(6):1311–20.
[7] Lin MP, Chang SC, Wu RH, Chou CK, Tzeng WS. A comparison of computed tomography, magnetic resonance imaging, and digital subtraction
angiography findings in the diagnosis of infected aortic aneurysm. J Comput Assist Tomogr 2008;32(4):616–20.
[8] Litmanovich D, Bankier AA, Cantin L, Raptopoulos V, Boiselle PM. CT and MRI in diseases of the aorta. AJR Am J Roentgenol 2009;193(4):928–40.
[9] Bosniak MA. An analysis of some anatomic-roentgenologic aspects of the brachiocephalic vessels. Am J Roentgenol Radium Ther Nucl Med
1964;91:1222–31.
[10] Hiratzka LF, Bakris GL, Beckman JA, Bersin RM, Carr VF, Casey DEJ, et al. 2010 CCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guide-
lines for the diagnosis and management of patients with Thoracic Aortic Disease: a report of the American College of Cardiology Foundation/
American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, American College of Radiology,
American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of
Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine. Circulation 2010;121:e266–369.
[11] Davies RR, Goldstein LJ, Coady MA, Tittle SL, Rizzo JA, Kopf GS, et al. Yearly rupture or dissection rates for thoracic aortic aneurysms: simple
prediction based on size. Ann Thorac Surg 2002;73:17–27. Discussion 27–8.
[12] Castrucci M, Mellone R, Vanzulli A, De Gaspari A, Castellano R, Astore D, Chiesa R, Grossi A, Del Maschio A. Mural thrombi in abdominal aortic
aneurysms: MR imaging characterization–useful before endovascular treatment? Radiology 1995;197(1):135–9.
[13] Corti R, Osende JI, Fayad ZA, Fallon JT, Fuster V, Mizsei G, Dickstein E, Drayer B, Badimon JJ. In vivo noninvasive detection and age definition
of arterial thrombus by MRI. J Am Coll Cardiol 2002;39(8):1366–73.
[14] Hellmann DB, Grand DJ, Freischlag JA. Inflammatory abdominal aortic aneurysm. JAMA 2007;297(4):395–400.
[15] Nienaber CA, von Kodolitsch Y, Nicolas V, et al. The diagnosis of thoracic aortic dissection by noninvasive imaging procedures. N Engl J Med
1993;328(1):1–9.
[16] Shiga T, Wajima Z, Apfel CC, Inoue T, Ohe Y. Diagnostic accuracy of transesophageal echocardiography, helical computed tomography, and mag-
netic resonance imaging for suspected thoracic aortic dissection: systematic review and meta-analysis. Arch Intern Med 2006;166(13):1350–6.
[17] Pereles FS, McCarthy RM, Baskaran V, et al. Thoracic aortic dissection and aneurysm: evaluation with nonenhanced true FISP MR angiography in
less than 4 minutes. Radiology 2002;223(1):270–4.
[18] Gornik HL, Creager MA. Aortitis. Circulation 2008;117:3039–51.
[19] Pipitone N, Versari A, Salvarani C. Role of imaging studies in the diagnosis and follow-up of large-vessel vasculitis: an update. Rheumatology
(Oxford) 2008;47:403–8.
[20] Restrepo CS, Ocazionez D, Suri R, Vargas D. Aortitis: imaging spectrum of the infectious and inflammatory conditions of the aorta. Radiographics
2011;31:435–51.
Chapter 20
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CT and MRI in Acute Aortic Syndrome
Ioana Smarandita Lacau
Regina Maria Ponderas Academic Hospital, Bucharest, Romania
Chapter Outline
Introduction 215
Choice of Imaging Modality 215
Computed Tomography Angiography of the Aorta 216
Magnetic Resonance Angiography of the Aorta 217
Aortic Dissection 217
INTRODUCTION
The term used in the recent years—acute aortic syndromes—is defined as a group of emergency entities that are interrelated and with similar characteristics. These entities are penetrating aortic ulcer, intramural hematoma (IMH), aortic dissection, and contained aortic rupture. All of them share a thing in common are caused by the rupture of aortic media with
hemorrhagic changes in a thick aortic wall (IMH), separation of the layers by blood entering through an intimal rupture
(aortic dissection), and penetration of the adventitia (aortic rupture). Penetrating aortic rupture is a predissection situation
or discovering dissection of aorta in her early stages, just before the intima ruptures completely and the blood is preparing
to evolve through the aortic layers [1,2]. There are two commonly used classifications for acute aortic syndromes, both
of them providing descriptive and prognostic information [3]. The main topic is whether the aortic syndrome involves the
ascending aorta thus needing immediate treatment—usually surgical. The Stanford classification defines two types: type A
when the aortic syndrome involves ascending aorta and/or aortic arch and eventually progresses distally and type B is the
aortic syndrome that starts at the level of the descending aorta. The DeBakey classification divides aortic dissection into
three types—type I involving both ascending and descending aorta, type II only the ascending aorta and the arch, and type
III only the descending aorta—with further subdivision in Class 1 for classic dissection and Class 2 for IMH.
Intramural Hematoma 218
Penetrating Aortic Ulcer 219
Conclusion 221
References 221
CHOICE OF IMAGING MODALITY
For a patient with the clinical suspicion of acute aortic syndrome, the main questions we have to answer are is it an acute
aortic syndrome? If so, what type and more descriptive, little but important issues: localization of tears, assessment of
extent of dissection, indicators of urgencies: hemorrhage (pericardial, pleural, mediastinal) and biomarkers; myocardial
markers of necrosis, D-dimer elevation more than 500 μg/L, and smooth muscle myosin heavy chain.
The answer to these questions, both imaging and laboratory results, will help us to plan treatment, although an ideal
algorithm has yet to be determined, mainly because it is tailored to the local expertise.
The clinical suspicion of an acute aortic syndrome is high when the patient has an abrupt and severe pain retrosternal on interscapular, usually migrating down the back, and in these patients, there might be some additional associated findings like signs of
aortic insufficiency, pericardial effusion, pulse differential due to side branch occlusion, or ST segment elevation due to ischemia
caused by coronary involvement. The suspicion is stronger if the patient has additional predisposing factors: hypertension, bicuspid aortic valve, connective tissue disorders, coarctation, previous cardiac surgery, or recent percutaneous instrumentation [4,5].
For patients with a strong suspicion of acute coronary syndrome, the imaging modality of choice is transthoracic echocardiography with additional computed tomography (CT) and/or transesophageal echocardiography (TEE) of thoracic aorta. Both imaging
modalities provide further information of localization and extent—proximal or distal dissection—and allow for further strategic planning. The role of magnetic resonance imaging (MRI) is limited in acute settings but might be useful in the follow-up [6].
New Approaches to Aortic Diseases from Valve to Abdominal Bifurcation. http://dx.doi.org/10.1016/B978-0-12-809979-7.00020-1
Copyright © 2018 Elsevier Inc. All rights reserved.
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The main subject is to adapt protocols to local expertise in the case of both chronic and suspected acute aortic syndrome,
considering that all imaging modalities have excellent accuracy [7]. Still, for unstable patients, TEE is the tool of choice
because it can be performed at bedside in patients unfit for transportation and in the operating theater, knowing that for this
modality the abdominal arterial segments are hard to see in the subcostal view [8]. Multislice CT has evolved as a rapid
technology that replaced invasive angiography and provides robust and quick information, with high-spatial revolution
to differentiate dissection, IMH, and penetrating ulcers but, of course, it involves transportation and stable hemodynamic
conditions [9–11].
Magnetic resonance angiography (MRA) is a diagnostic modality that allows us to appreciate aorta with high-resolution
images that allow three-dimensional acquisition and postprocessing that can be acquired with or without administration
of contrast agent. The use of MRA allows us to visualize intimal flaps and aneurysms—even asymptomatic ones—and to
further characterize the aortic wall: presence of IMH, aortic ulcers, inflammation processes; these processes are reported
with increased frequencies than using CT [12].
Compared with CT, MRA of the aorta has a lower spatial resolution and it is influenced by the presence of calcium but
still can diagnose correctly lumen narrowing and intimal flaps; metallic implants contraindicate the examination or they
modify local magnetic field and produce artifacts. Large metallic objects stop the X-rays and degrade the CT image but
small implants do not significantly influence the CT image.
The analyses of small vessels for extension of dissection are better with CT—and in some cases with electrocardiogram
(ECG)-gated CT—and it is influenced with MRI due to significant flow artifacts [13,14].
In patients suspected with acute aortic syndrome and that are known with severe allergy to iodinated contrast agents,
there is a recommendation to use gadolinium-based contrast agent (60–80 mL); the contrast is not as good as iodine administration but it is good enough to allow acquisition of diagnostic images. In the case of considering endovascular repair of
the dissection or the aneurysm, it is essential to know the quantitative morphology of aneurysm or dissection and also the
status of branch arteries provided by CT or MRI; thus either modality is recommended [13,15].
However, MRA is ideal for the follow-up in patients with thoracic aorta pathology rather than competing imaging
modality in patients with acute aortic syndromes [11].
COMPUTED TOMOGRAPHY ANGIOGRAPHY OF THE AORTA
There are three interrelated entities that define acute aortic syndrome: penetrating atherosclerotic ulcer, IMH, and
aortic dissection. The incidence of those entities is 2.6–3.5 cases per 100,000 persons per year in population-based
studies and two-thirds of the patients are male. The most prevalent conditions that increase the risk of acute aortic syndrome are related to lifestyle (smoking), trauma (deceleration, iatrogenic), and preexisting conditions (longstanding hypertension, atherosclerosis, dyslipidemia, pregnancy, connective tissues disorders: Marfan syndrome;
hereditary fibrillinopathies; hereditary capsular diseases; Ehlers–Danlos syndrome; congenital anomalies, bicuspid
aortic valves; coarctation and vascular inflammation, Takayasu arteritis; Behcet disease, Ormond disease; giant cell
arteritis; syphilis) [3,16,17].
The main symptom is excruciating pain and its first localization is suggestive for the initial intimal rupture—pain
localization may change due to dissection’s evolution and the involvement of other arteries or organs.
The majority of patients that experience acute chest pain in patients are diagnosed with acute myocardial infarction
(30%), but there are other mediastinal causes that include trauma, blunt or penetrated, vessel-related, trombembolism and
acute aortic syndromes, and nonvascular nontraumatic mediastinal conditions, acute mediastinitis, esophageal emergencies
(IMH of the esophagus, Boerhaave syndrome, acquired esophagorespiratory fistula), spontaneous mediastinal hematoma,
tension pneumomediastinum, and tension pneumopericardium [18].
The main goal of imaging is confirmation of the aortic wall lesion, followed by ascertain the site, extension, and complications of the disease; these are important to plan the most appropriate and timely management approach. Universal
availability, rapid acquisition, and high accuracy make multidetector CT (MDCT) the imaging modality of choice in the
emergency setting [17].
The technical evolution of MDCT with the cone-shaped X-ray beam generating data from a volume rather than one
axial image per rotation allows three-dimensional display along the centerline of the flow, offers the opportunity to view a
vessel in multiple projections and orientations, and permits visualization of anatomic details such as tortuosity, dilation, or
aortic spiral dissection.
It is a fast technique permitting high-definition CTA images of the entire aorta, neck vessels, and iliac arteries in less
than 20 s. The significant drawback is the radiation dose of 10–25 mSv [19,20].
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When there is a clinical suspicion of aortic root lesion, ECG-gated acquisition can be performed and it is often used in
the emergency room as part of a triple rule-out protocol that provides simultaneous evaluation of coronary arteries disease,
aortic disease, and presence of pulmonary embolism. This protocol is associated with a slightly higher yield of pulmonary
embolism and aortic disease compared with coronary CT angiography, but this benefit comes with higher nondiagnostic
image quality, radiation, and contrast doses [21].
Unlike other CTA acquisition, for suspected acute aortic syndromes, it is mandatory to obtain unenhanced images that
will help to diagnose the IMH [2,4], thus differentiating among the components of this entity; the unenhanced scan is also
helpful in visualizing vascular calcifications that are usually intimal but can appear in the middle of the vessel, suggesting the separation of the wall layers. If there is only a contrast-enhanced scan, it is difficult to discriminate between florid
atherosclerosis and IMH.
The second acquisition will be a thin-sliced contrast enhanced during a bolus administration of iodine contrast agent
with a flow rate no less that 3–4 mL/s; this is optimal with bolus tracking because vascular imaging has to be done in arterial
phase and is dependent on the iodine flux [22].
Delayed phase, which is done immediately after the arterial phase, usually caudo-cranial, is useful to evaluate the entry
point and false lumen. If the entry point is distally on the arterial phase, the X-ray tube may be faster than the contrast in
the false lumen; so an immediate delayed phase shows us the extent of false lumen and the presence of thrombosis and can
also show endoleaks in stented patients and permit the lesion evaluation in solid organs.
Due to the acquisition principle, CT is used for arterial diagnosis and it has some characteristics that we need to be
aware of when correlating the clinical signs with images: in aortic side branches with calcified plaque, there is a tendency
to overestimate the stenosis due to blooming artifacts and in noncalcified plaques there is a tendency to underestimate the
luminal narrowing. Also, in obese patients, the images suffer due to inadequate penetration of X-rays and insufficient contrast due to scatter radiation and so noise appears and can cause imaging distortion [15].
MAGNETIC RESONANCE ANGIOGRAPHY OF THE AORTA
In acute aortic syndromes, the use of magnetic resonance is rather complementary because the accessibility is low and the
scan time is long and in life-threatening situations medical personnel cannot enter in the magnet room with metal objects. It
is an ideal method for follow-up of these patients because it does not use ionizing radiation and it can also be done without
the contrast agent or in patients with allergies at the iodinated contrast agent.
Magnetic resonance allows the acquisition in any plane, regardless of anatomic particularities, and with cardiac and
diaphragmatic trigger it can be done in patients unable to hold their breath; however, they have to be able to stay on the
examination table for at least 10–15 min. It has good spatial and temporal resolution and can provide real-time video
sequences allowing the estimate of instantaneous hemodynamics and can be used to longitudinally follow evolution
from acute to chronic phase using reconstructions–multiplanar, volume rendered, virtual endoscopy, or multiple intensity
projection [23].
MR is actually imaging of water and using a succession of gradients applied to the atoms of hydrogen provides best
tissue characterization of aortic wall—delineating atheroma, IMH, intimal flaps, and allows flow quantification. Ideal is
the use of ECG-triggered sequences that will reduce heart moving artifacts but it will increase the examination time and it
is not feasible in acute patients. Static sequences are used to delineate anatomy (T1 weighted black blood), to characterize
pathology (T2 weighted black blood especially with fat saturation), and dynamic and functional information is provided
with gradient-echo (balanced single shot free precession) and flow imaging [24].
Angiography sequences with contrast agent administration are short sequences with high resolution but in patients with
low glomerular filtration rate or allergic to gadolinium, there are noncontrast angiography sequence developed, making the
examination longer but with good resolution [25,26].
AORTIC DISSECTION
Aortic dissection represents the separation of aortic wall layers and the most common trigger is elevated blood pressure in
a patient with degenerative changes in aortic media.
The sites of maximum hydraulic stress points are the right lateral wall of the ascending aorta and the proximal segment
of the descending aorta and are the most common sites of an entrance tear in the intima [27].
Once the intimal tear appears, aortic blood gets direct access to the layers of the aortic wall, where there is lower pressure, so it propagates in the media. The blood then progresses anterograde and/or retrograde and the result is a new lumen
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called false lumen where the pressure is equal to or greater than the true lumen and usually the false lumen is bigger in
caliber compared to the false lumen [28]. Distinction between the true lumen and false lumen is essential for both surgical
repair and planning a percutaneous intervention.
There are two classification systems commonly used for aortic dissection and are based on location and extension of
the dissection: DeBakey [29] and Stanford [30]. Because it suggests immediate clinical management, the most commonly
used is Stanford classification and allows differentiation between surgical management (type A) and medical management
(type B).
In emergency settings, the specificity and sensitivity of transesophageal echocardiography, multidetector CT and MRI
in the diagnosis of aortic dissection are comparable. For the thoracic aortic dissection, however, multidetector CT has a
sensitivity and a specificity of 100% and 98% and is superior to the other techniques in ruling it out, mainly because the
entrance tear is in general perpendicular to the aortic wall and it is well recognized on axial images [7,31].
The intimal flap is seen in approximately 70% of cases with CT and represents a thin hypodense curved line inside the
aortic lumen that continues the tear and separates aorta in two parts: the true lumen that usually is of lesser caliber and the
false lumen [32].
The true lumen can be followed entirely in the aorta, also in the nondissected portions, and is visible in almost all cases.
It is important to describe where the side branches originate from: true lumen or false lumen. The differentiation between
the true and the false lumen is difficult in cases involving the aortic root, especially in circumferential dissection of the
aortic root [33].
In the dissection that involves the entre intima, a circumferential flap is formed [32,33].
The most useful indicators of the false lumen are the beak sign, which is a wedge of hematoma that creates space for the
propagation of the false lumen, and the larger cross-sectional area of the false lumen compared with the true lumen [34].
For identifying the false lumen, we can use specific signs like the “cobweb” sign, ribbons of media that are incompletely
sheared off by the dissection, and the intimo-medial flap rupture communicating with the false lumen; however, these signs
are infrequently encountered [34,35]. False lumen thrombus may appear and can be partial or complete and this is a sign
more frequently seen in chronic dissection. This is why it is important to do another scan from bottom to top immediately
after the pure arterial phase; if the entry point is inferior, the CT machine can scan faster than the contrast propagation in
the false lumen, so it can mimic thrombosis.
An aortic dissection Stanford type A means that the intimal flap is in the ascending aorta, between the aortic root and the
origin of the last supraaortic vessel and can extend to the descending aorta.
A type A aortic dissection is a true emergency because it can be lethal and therefore requires urgent surgical treatment;
using CT we can also image complications like coronary artery occlusion or dissection, pericardial tamponade, and organ
malperfusion (Figs. 20.1 and 20.2).
A Stanford type B dissection involves the descending aorta beyond the last origin of the cervical vessels and can be
treated conservatively. Nevertheless, if the patient develops ischemic complications (organ malperfusion, renal failure)
or there are signs of impending rupture then immediate aortic repair using an endovascular stent or surgical procedure is
indicated [36].
An acute type B aortic dissection with partial thrombosis of the false lumen requires more intensive follow-up. These
dissections have a significantly higher annual growth rate than dissections with patent or complete thrombosis of the false
lumen and patients may benefit from prophylactic intervention [37].
INTRAMURAL HEMATOMA
IMH is classically defined as acute hemorrhage contained in the aortic wall; it was described as a different variant of
aortic dissection but recently, by the use of intravascular ultrasound, subtle intimal tears were detected in acute IMH
[38].
IMH can be caused by a thoracic trauma but it can appear also spontaneously as a natural evolution of an aortic ulcer.
Earlier theories postulated that the IMH appears due to a rupture in vasa vasorum but investigators reported that IMH
may result from multiple microscopic tears in the aortic intima and aortic wall hemorrhage can lead to aortic wall infarction,
which is the precursor of aortic dissection [12].
Current opinion about IMH is that it can be a variant or a precursor of aortic dissection, and many investigators have
suggested that IMH is synonymous with a thrombosed type or noncommunicating aortic dissection; the blood between the
layers is contained, so actually the separation between the aortic layers is a thrombosed false lumen [20] (Fig. 20.3).
Acute IMH accounts for 5%–15% of all cases of acute aortic syndrome [39] and the most common finding is a hyperdense crescent on unenhanced CT scan.
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FIGURE 20.1 Stanford type A aortic dissection. Axial and coronal multiplanar reconstruction and 3D volume rendering from an arterial phase nonECG-gated multislice computed tomography angiography. There is an intimal flap (blue arrow) in an increased size ascending aorta in the presence of a
complex partial calcified plaque.
One way to differentiate IMH from a thrombosed false lumen of aortic dissection is that IMH maintains a constant circumferential relationship with the aortic wall, whereas a dissection tends to spiral longitudinally [36].
IMH treatment is the same as aortic dissection treatment: surgery for type A and medical management for type B.
PENETRATING AORTIC ULCER
Aortic intima can be severely diseased so a plaque may erode the internal elastic lamina and progress in the media of the
aortic wall. This may be true in elderly patients with advanced atherosclerosis or in younger patients with connective tissue
diseases or after rupture of a mycotic plaque. The incidence of penetrating aortic ulcer (PAU) in patients presenting with
acute aortic syndrome is estimated to be between 2.3% and 7.6% [40].
The plaque rupture will cause a hemorrhage that can evolve into a limited medial dissection or a saccular pseudoaneurysm [39] (Fig. 20.4).
An important imaging feature of PAU is the outpouching of the aortic wall with jagged edges, usually in the presence of
extensive aortic atheroma and intimal calcification [41].
The common location of PAUs is the descending thoracic aorta because atherosclerotic plaques are more common here [42].
The prognosis of PAU is unfavorable with a higher incidence of aortic rupture than aortic dissection mainly because it
appears on a previously diseased aortic wall [40,41].
Aortic dissection secondary to an aortic ulcer is shorter in extension, is farther away from classic entrance tears, and has
a thicker calcified and static flap [36].
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FIGURE 20.2 Stanford type A aortic dissection. Sagittal and transverse T2-weighted gradient echo, coronal T1-weighted and volume rendering magnetic resonance angiography. There is an intimal flap with entering point in ascending aorta; the flap has a spiral evolution in ascending and descending
aorta.
FIGURE 20.3 Intramural hematoma. Oblique sagittal bright blood gradient echo in a patient with graft in ascending aorta for operated type A dissection.
There is a crescent-shaped intramural hematoma in proximal descending aorta.
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FIGURE 20.4 Penetrating atherosclerotic ulcer with saccular aneurysmal formation before and after successful interventional treatment. Multislice
computational tomography with mutiplanar, maximum intensity projections, and three-dimensional volume rendering before and after percutaneous
intervention.
CONCLUSION
Acute aortic syndrome is referred to multiple aortic entities that have similar clinical presentation and management. Imaging
techniques play an important role in diagnostic and management guidance and are used considering clinical settings and
local expertise.
In acute stable patients, multidetector CT plays a crucial role in describing location of the dissection, extent of the disease and description of complications.
MRI has a complementary role in acute settings, but it is an important tool in the follow-up of these patients.
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