Disease of aorta and aneurysm by Dr. Crystal KC

1. RADIOLOGICAL APPROACH TO
AORTIC ANEURYSM
AND ACUTE DISEASES
Dr. Crystal K C
Resident
MD Radiodiagnosis
NAMS, BIR Hospital

2. Anatomy
• Aorta begins in the aortic root as ascending aorta.
• The aortic arch begins at the innominate artery and ends at the
ligamentum arteriosum. Its most distal aspect, which is often slightly
narrowed, is termed the “aortic isthmus.”In some cases small
diverticulum called ductus diverticulum.
• The descending aorta begins at the ligamentum. Its proximal portion
may appear slightly dilated and has been termed the “aortic spindle.”

3. Fig: Normal angiographic anatomy: Arch(DSA)
shows normal branches

4. Branches of Aorta
Descending thoracic aorta
• Visceral branches:
Pericardial branches,
Bronchial arteries (one on
the right and two on the
left side), Mediastinal
branches, Phrenic branches.
• Parietal branches:
Intercostal arteries,
subcostal arteries
Abdominal aorta
Ventral: Unpaired-coeliac axis,
superior mesenteric,
inferior mesenteric
Lateral: Paired-inferior phrenic,
Middle suprarenal, Renal,
Testicular or ovarian
Dorsal: Lumbar (5-Paired), Median
sacral (Unpaired)
Terminal: Common iliac (Paired).

5. Variant Anatomy
• This normal branching pattern is seen in about 70% of individuals.
• Left CCA and Brachiocephalic trunk have common origin -20–30% of
individuals, most common => Bovine arch.
• In about 5% of cases, the left vertebral artery arises as a separate branch
directly from the aorta, between the left common carotid artery and the left
subclavian artery.
• Common origin of both CCA.
• Paired brachiocephalic trunk.

6. Variant anatomy – Abdominal Aorta
• left hepatic artery originating from
the left gastric artery (25%).
• The “replaced origin” of the right
hepatic artery from the superior
mesenteric artery (SMA) in 10% of
the
• The common hepatic artery may
take origin directly from the SMA
or the aorta
• The celiac axis and SMA may have a
common origin.

7. • Aneurysm
• A localized abnormal dilatation of
an artery, vein, or the heart.
• Aortic aneurysm
• thoracic
• abdominal
• thoracoabdominal

8. Maximal Normal Aortic Diameter
Segment Size (cm)
Ascending 4
Descending thoracic 3
Abdominal 2

9. CLASSIFICATION
• TRUE VS FALSE
• True aneurysm
• all layers
• False aneurysm-
• contained by
• adventitia or
• perivascular connective tissue and
organized hematoma
• FUSIFORM VS SACCULAR
• Fusiform aneurysm
• Circumferential involvement
• Saccular aneurysm
• Portion of a wall

10. Causes of aortic aneurysms
• Atherosclerosis(70-90%)
• Traumatic ( 15-20%)
• Congenital (2%)- aortic sinus, postcoarctation, ductus
diverticulum.
• Syphilis
• Mycotic
• Cystic media necrosis( Marfan, Ehlers-Danlos syndrome,
annuloaortic ectasia)
• Inflammation of media+ adventitia-
• Takayasu arteritis, Giant cell arteritis, Rheumatic fever, Rheumatoid
arthritis, Ankylosing spondylitis, Reiter syndrome, etc.

11. Atherosclerotic aneurysm
• Cause - Atherosclerosis of the aorta
• In elderly
• Location
• Descending aorta distal to Left
SCA.
• Infrarenal aorta
• Thoracoabdominal
• Fusiform- 80%, saccular-20%

12. Mycotic aneurysm
• Infectious break in the wall of an artery with formation of a blind,
saccular outpouching that is contiguous with the arterial lumen.
• Predisposing factors
• IV drug abuse
• Bacterial endocarditis (12%)
• Immunocompromise (malignancy, steroids, chemo, DM, etc.)
• Infected prosthetic valves or sternal wires

13. • Organisms
• S. aureus (53%)
• Salmonella (33-50%)
• Streptococcus
• Mycobacterium ( contiguous spread from spine/lymph node)
• The most common cause of an infected aneurysm is direct deposition of
circulating bacteria in a diseased, atherosclerotic, or traumatized aortic
intima, after which organisms penetrate the aortic wall through
breeches in intimal integrity to cause microbial arteritis.

14. • Site
Ascending aorta > visceral artery > intracranial artery >
upper/lower extremity artery.
• Poor prognosis due to quick expansion- rupture.

15. Findings in mycotic aneurysm
1. Unusual location (non infrarenal)
2. Saccular aneurysm
3. Irregular contour
4. Lack of calcification
5. Rapid enlargement
6. Signs of infection
• Perianeurysmal air
• Perianeurysmal fluid collection with enhancing wall
• Enlarged perianeursymal lymph nodes
• Osteomyelitis of adjacent vertebra

16. Images obtained in a 73-year-old man with infected infrarenal aortic aneurysm associated with
osteomyelitis and psoas muscle abscess. (a) Transverse contrast-enhanced CT scan shows an
infrarenal aortic aneurysm (*) measuring 11 x 6 cm in diameter associated with a left psoas muscle
abscess (arrowhead) and vertebral body destruction (arrow). (b) Sagittal T1-weighted MR image
shows abnormal signal intensity (arrow) in the bone marrow of the vertebral body.

17. Abdominal aortic aneurysm
• Abdominal aortic aneurysms (AAAs) are segmental
dilatations of the aortic wall that cause the vessel to be
larger than 1.5 times its normal diameter or that cause the
distal aorta to exceed 3 cm.
• Prevalence:
• Increases with age
• Greater with atherosclerotic disease
• Male predominance
• Whites: Blacks = 3:1

18. •Risk factors:
• male
• age >75 years
• white race
• prior vascular disease
• hypertension
• cigarette smoking
• family history
• hypercholesterolemia

19. Associated with:
• occlusion of inferior mesenteric artery (80%)
• occlusion of lumbar arteries (78%)
• stenosis of renal artery (22-30%)
• stenosis / occlusion of celiac trunk / SMA (22%)
• isolated iliac + femoral artery aneurysm (16%)
• common iliac (89%), internal iliac (10%), external iliac (1%)
• visceral + renal artery aneurysm (2%)

20. • Clinical
• abdominal pain (37%)
• asymptomatic (30%)
• abdominal mass (26%)

21. Anatomical classification
• In relation to the renal arteries.
• Suprarenal
• Juxtarenal (within 1.5 cm of renal artery origin)
• Pararenal (involving one or both renal arteries)
• Infrarenal
• ~90-95% of AAAs -infrarenal
• Extension above renal arteries
• rare
• Extension to common iliac arteries
• fairly common (66-70%).

22. Progression of AAA
• Over time, ~80% enlarge.
• Most enlarge slowly.
• Larger- faster.
• smaller-slower
• >=5cm 4-8mm/year
• 4-5cm 3-7mm/year
• <4cm 2-5mm/year

23. Imaging modalities
Plain X-ray:
• mural calcification (75-86%)
• US initial screening
• If the aneurysm is approaching 5 cm or more or if rapid enlargement
is seen on serial US images
• CT and CTA/ MR and MRA
• Angiography

24. Curvilinear calcification (arrowheads) is consistent
with a significant size calcified abdominal aortic
aneurysm.
The lateral view clearly shows calcification of
both walls. Abdominal aortic aneurysm can be
diagnosed with certainty- egg shell
calcification.

25. USG
• >98% accuracy in size
measurement
• screening examination of choice as
a result of its relative availability,
speed, low cost and no radiation.
• Problems with
• obese pt
• distended bowel with gas
• proximal iliac arteries

26. US findings:-
•Focal dilatation
beyond normal.
•Any increase in the
size as the aorta
travels distally is
abnormal

27. • US findings of rupture
• Partially encapsulated hematomas - a hypoechoic or anechoic paraaortic
space-occupying lesion.
• Color Doppler-site of leak or extravasation

28. CT-non-contrast
• perianeurysmal fibrosis (10%)
• "crescent sign" = peripheral high-attenuating crescent in aneurysm wall
(= acute intramural hematoma) = sign of impending rupture

29. CT-contrast-enhanced
• Accurately demonstrates dilation of the aorta
• Extent of aneurysm
• Degree of calcification, presence of mural thrombus
• Major branch vessels proximally and distally-- helps in determining the
appropriate intervention (surgical or endovascular repair).
• Assessment of other abdominal organs possible.
• CTA -multiplanar assessment of the aneurysm and associated relevant
vessels (visceral arteries, iliac and femoral arteries).
• Complications

30. MRI
• MRI and MRA good alternatives
in
• impaired renal function and
• allergy to ICM

31. Angiography
• Often ordered for preoperative evaluation in patients with
manifestations of atherosclerotic vascular disease such as renal
artery stenosis or peripheral vascular disease.
• The role of angiography is in planning surgical or endovascular
repair.
• Largely replaced by CTA or MRA.

32. Angiography findings
• focally widened aortic lumen
>3 cm
• mural clot (80%)
• apparent normal size of
lumen secondary to mural
thrombus (11%)
• slow antegrade flow of
contrast medium

33. Lateral aortogram in a patient with severe mid back pain and lumbar spine images
which demonstrated anterior erosion of the lower thoracic vertebral bodies. The
angiogram demonstrates that this has been caused by a pulsatile thoracoabdominal
aortic aneurysm.

34. Complications:
• Rupture (25%)
• Peripheral embolization
• Infection
• Spontaneous occlusion of aorta
• Pseudoaneurysm
• Compression of adjacent structures
• Anterior vertebral scalloping

35. Rupture
•Sites
• into retroperitoneum: commonly on left
• into GI tract: massive GI hemorrhage
• into IVC: rapid cardiac decompensation
• Symptoms of rupture
• sudden severe abdominal pain ± radiating into back
• fainting, syncope, hypotension
• Prognosis:64-94% die before reaching hospital

36. High risk for rupture of AAA
• >5cm
• Rapid growth ( >5mm per 6
months) or a diameter of
7cm
• Mycotic aneurysm
Signs of AAA rupture
• Primary signs
• Periaortic stranding
• Retroperitoneal hematoma
• Extravasation of IV contrast
• Secondary signs
• High attenuating crescent sign
• Focal discontinuity of intimal
calcification
• Tangential calcium sign
• Draped aorta sign
• Thrombus fissuration

37. Foccal discontinuity of
intimal calcification
Tangential calcium sign:
Intimal calcification points
away from the aneurysm
and
there is retroperitoneal
leakage.

38. LEFT: Subtle periaortic stranding, MIDDLE: Hemorrhage into posterior pararenal and
perirenal compartment, RIGHT: Extravasation of iv. contrast

39. CECT-draped aorta sign: Posterior wall of the aneurysm is not seen and the
aneurysm extends around the vertebral body and on left paravertebral region
An important imaging feature that
may be seen in a contained
rupture of an abdominal aortic
aneurysm is the draped aorta
sign. This sign is considered
present when the posterior wall
of the aorta either is not
identifiable as distinct from
adjacent structures or when it
closely follows the contour of
adjacent vertebral bodies.

40. Aortic aneurysm with high-attenuation
crescents

41. Ruptured aneurysm
• anterior displacement of
kidney
• extravasation of contrast
material
• fluid collection / hematoma
within posterior pararenal +
perirenal spaces
• free intraperitoneal fluid

42. False positive CT dx of aneurysm rupture
• Asymmetric aneurysm thrombus
• Partial volume averaging of periaortic tissue at the level of
the aneurysm neck.
• Perianeurysmal fibrosis( in NECT)
• Unopacified 3rd and 4th portion of Duodenum.
• Retroperitoneal lymphadenopathy.

43. Pre-op assessment of AAA
• We should assess :
• Maximum diameter of the aneurysm
• Proximal and distal extent of aneurysm
• Assessment of iliac and renal arteries
• Perianeurysmal fibrosis
• Congenital variations:
• Accessory renal arteries
• Retroaortic course of left renal vein
• CT/CTA or MR/MRA is required for pre-op assessment.
• USG is not enough because:
• Perianeurysmal soft tissue can not be assessed
• Relation with renal arteries & congenital variations are difficult to assess

44. Intervention
• Open surgery
• Endovascular repair

45. Open surgery- indications
(1) Any patient with a documented rupture or suspected
rupture;
(2) symptomatic or rapidly expanding aneurysm, regardless of
its size;
(3) aneurysms larger than 5 cm in diameter;
(4) complicated aneurysms with embolism, thrombosis, or
symptomatic occlusive disease; and
(5) atypical aneurysms (eg, dissecting, mycotic, saccular).

46. Endovascular aortic aneurysm repair (EVAR)
• EVAR has been shown to reduce blood loss, operative time, length of
hospital stay, mortality, and morbidity compared with open surgical
repair of infrarenal abdominal aortic aneurysms (AAAs).

47. Endovascular repair such as stent-graft
placement
gain access to the
lumen of the
abdominal aorta,
usually via small
incisions over the
femoral vessels.
Endograft is placed
within the lumen
of the AAA
extending distally
into the iliac
arteries.
serves as a bypass
and decreases the
pressure on the
aortic wall, leading
to a reduction in
AAA size over time
and a decrease in
the risk of aortic
rupture.

49. Endoleaks.
• Persistent flow in an excluded aneurysmal sac after endovascular treatment
with stent graft.
• Type I: leak at graft attachment site
• Ia: proximal, Ib: distal and Ic: iliac occluder
• Type II: aneurysm sac filling branch vessel {M/C}
• IIa: single vessel, IIb: 2 or more vessels
• Type III: leaks through defect in graft
• IIIa junctional separation of modular component, IIIb fracture or holes
• Type IV: leak through the graft fabric as result of graft porosity
• Type V: continued expansion of aneursymal sac without demonstrable leak
on imaging (ENDOTENSION)

50. • Close follow-up is required
• CT scans performed at one, six, and 12 months, and then
yearly

51. Thoracic aortic aneurysm
• Aneurysmal dilatation of ascending, arch, or descending
thoracic aorta.
• Aneurysm - localized or diffuse dilatation of more than 50%
normal diameter of the aorta.

52. Anatomical classification
Type Cause
1.Aneurysm of sinus of Valsalva
2. Ascending aorta
3. Arch of aorta
4. Descending aorta
5. Aortic isthmus
1.Congenital, Syphilis
2. Atherosclerosis, Marfan syndrome, Ehlers- Danlos
syndrome, syphilis, mycotic aneurysm
3. Atherosclerotic
4. Atherosclerotic
5. Post traumatic aneurysm

53. • Descending aorta
>ascending aorta >Arch of
Aorta aneurysms
• Descending aortic thoracic
aneurysms may extend
distally to involve the
abdominal aorta and create
a thoracoabdominal aortic
aneurysm.
• Mean age 65 years
• M:F 3:1
• Clinical features
• Substernal/back/shoulder pain
• SVC syndrome ( venous
compression)
• Dysphagia (esophageal
compression)
• Stridor, dyspnea
( tracheobronchial)
• Hoarseness (recurrent laryngeal
nerve com)

54. Imaging of thoracic aneurysms:
•Modalities:
•CXR
•CT/CTA
•MR/MRA
•TEE
•Aortography

55. CXR
• Many readily visible on CXR.
• Findings
• (1) widening of the
mediastinal silhouette,
• (2) enlargement of the
aortic knob
• (3) displacement of the
trachea/esophagus from
the midline.

56. TEE
–can be quickly performed at
bedside under sedation without
radiation or the injection of
contrast material.
–excellent at detecting pericardial
effusion and aortic regurgitation
–90% accuracy in imaging intimal
membranes for signs of aortic
dissection
• Disadvantage - poorly depicts
aneurysms below the diaphragm and
in the transverse aortic arch.
Atherosclerotic and
enlarged descending
aorta with eccentric
thickening of the wall.

57. CT/CTA
• primary diagnostic test of choice in most institutions
• reliable test for diagnosing aneurysm and dissection
• effective to define maximum diameter
• To monitor diameter over time.
• Findings:
• increase in aortic diameter
• outward displacement of calcium of the aortic wall.

60. MR/MRA
• Alternative of CT/CTA specially in pt with
• impaired renal function and
• allergy to ICM
• Velocity-encoded cine MRI
• measurement of the differential flow velocity in the true and
false channels
• to quantify the volume of concomitant aortic regurgitation in
patients with aortoannular abnormalities.

61. Aortography
• The criterion standard until late
• But rarely used with the advent
of helical CT/MRI/MRA/TEE
• Still a modality for
• pre-op evaluation of
thoracic aortic aneurysms
• for precise definition of the
anatomy of the aneurysm
and great vessels
Ascending aortogram showing
ascending aortic aneurysm.

62. Thoraco- Abdominal Aneurysms
• Type I and Type II TAAAs involve the entire thoracic aorta extending
distally to or beyond the renal arteries, respectively.
• Type III TAAAs start below the T6 level and extend beyond the renal
arteries.
• Type IV TAAAs are the simplest form, starting at the level of the celiac
axis and extending distal into the infrarenal aorta or iliac arteries.
• Type VI: start below the T6 level and extend upto the renal arteries.

64. Aortic Dissection
• Separation of the aortic
intima with tear in it
communicating with the
true lumen.
• True lumen-inside the intima
• False lumen-outside the
intima
Most dissections arise either
just distal to the aortic valve or
the aortic isthmus

65. Pathophysiology
• The essential feature of aortic dissection is a tear in the intimal layer,
followed by formation and propagation of a subintimal hematoma.
• The dissecting hematoma commonly occupies about half and
occasionally the entire circumference of the aorta. This produces a
false lumen or double-barreled aorta, which can reduce blood flow to
the major arteries arising from the aorta.
• Aortic dissection often occurs along the right lateral wall of ascending
aorta and descending thoracic aorta just below the ligamentum
arteriosum.
• The dissection usually propagates distally down the descending aorta
and into its major branches, but it also may propagate proximally.

66. New Theory
Degeneration of
media
Rupture of Vasa
Vasorum of Aortic
Wall
DISSECTING
HEMATOMA-may or
may not rupture
through the intima
into lumen

67. C/F:-
• Predisposing factors
• Starts in fusiform aneurysms in
28 % cases
• Hypertension (60-90%)
• Marfan syndrome
• Ehlers- Danlos syndrome
• Trauma
• Catheterization
• Aortitis
1. Sudden onset of sharp, tearing,
intractable chest pain, may radiate to
back, esp. interscapular region
2. Previously hypertensive, now possible
shock (Signs of peripheral organ blood
flow hypoperfusion, including decreased
urine output, ischemia bowel, ischemia
pain of lower extremities, etc.)
3. Asymmetric peripheral pulse
4. Diastolic murmur or bruit of aortic
regurgitation
5. Pulmonary edema
6. Signs result from compression of
adjacent tissues

68. Imaging Findings
Chest X-ray:
o Mediastinal widening
o Displacement of
intimal calcifications
o Apical pleural cap
o Left pleural effusion
o Displacement of
endotracheal tube or
nasogastric tube

69. • CT
• Intimal flap
• Displacement of intimal
calcification
• Differential contrast
enhancement of true versus false
lumen
• MRI
• Intimal flap
• Slow flow or clot in false lumen
• TEE
• Intimal flap
Angiography
• Intimal flap
• Double lumen
• Compression of true lumen by
false channel
• Obstruction of branch vessels

70. True versus false channel
False lumen:
• anterior in the ascending aorta
• larger caliber than true lumen
• beak sign: acute angle with intimal
flap at corner
• intimal flap curved towards false
lumen
• thrombus is common
• cobwebs due to medial strands
• Slower flow in false channel on MR
True lumen:
• continues with the lumen
of nondissected segment
• Posterior and left lateral -
descending aorta
• smaller caliber
• intimal calcification
towards true lumen

71. TEE view of the descending thoracic aorta in the
horizontal plane. An aortic dissection is manifested by
the presence of a true lumen (TL), a false lumen (FL),
and a free-floating intimal flap (F). LA left atrium

72. Axial double-inversion-recovery MR images (TR/TE, 1875/18; inversion time, 150 msec) of 37-
year-old man with Marfan syndrome. Image shows classic aortic dissection with double-
channel aorta. True lumen (straight arrow) is smaller than false lumen (curved arrow). High-
velocity flow in true lumen causes signal void. Slower flow with higher signal can be seen in
false lumen.

73. 61-year-old man with chest pain and acute type A aortic dissection. Axial enhanced CT
scan of ascending aorta shows type A aortic dissection with intimomedial tear (arrows)
entering false lumen (F) from true lumen (T). DA = descending thoracic aorta, PA =
pulmonary artery.

74. CT scan obtained at one-quarter distance along length of dissected portion of aorta
shows descending aortic dissection flap (arrows) that is curved toward false lumen
(F). Beak sign (arrowheads) is present in false lumen. Note that false lumen area is
larger than true lumen area

75. CLASSIFICATION SYSTEMS FOR AORTIC DISSECTION
Site of dissection Classification system
Crawford DeBakey Stanford
Both ascending and
descending aorta
Proximal dissections Type I Type A
Ascending aorta and arch
only
Proximal dissections Type II Type A
Descending aorta only
(distal to left subclavian
artery)
Distal dissections Type III
IIIa—limited to thoracic
aorta
IIIb—extends to
abdominal aorta
Type B

76. Aortitis
Causes:
• Takayasu arteritis
• Rheumatic fever
• Reiter’s syndrome
• Syphilis
• Begins above sinotubular ridge
• Giant cell arteritis
• Ankylosing spondylitis
• Crosses sinotubular ridge and
dilates both root and ascending
aorta
Sinotubular Ridge-
The sinotubular ridge is the portion of the ascending
aorta just distal to the sinuses of Valsalva at the
junction with the tubular segment of the ascending
aorta.

77. Takayasu arteritis
• Granulomatous vasculitis of unknown etiology
• Commonly affects the thoracic and abdominal aorta
• causes intimal fibroproliferation of the aorta, great vessels,
pulmonary arteries, and renal arteries
• results in segmental stenosis, occlusion, dilatation, and aneurysm
formation in these vessels.
• Takayasu arteritis is the only form of aortitis that causes stenosis
and occlusion of the aorta.

78. • Pathophysiology:
• Not fully elucidated to date.
• begins as a nonspecific, cell-mediated inflammatory
process in the patient's first 2 decades of life and
progresses to the formation of fibrotic stenoses of the
aorta and its major branches.

79. Clinical Details:
• 15-40 years
• 8:1 females,
• Early and late phases.
• Presenting symptoms are Non-
specific –
• Fever,
• Arthralgia and
• weight loss.
• In pulseless phase- s/s of ischemia of
limb, renovascular hypertension.
• The early phase –
• inflammatory -prepulseless phase
• Present with constitutional sign and
symptoms with positive lab findings
(Increased ESR, positive C-reactive
protein).
• Radiological findings show only
thickened vessel wall on CT and MR.
• Angiography is usually negative.
• The late phase
• occlusive -pulseless phase.
• has thickening of media and adventitia.
• Angiographic findings show smooth long
segment stenosis and occlusions of the
proximal great vessels.
• A 5- to 20-year interval between two
phases.

80. Four types of late-phase
Takayasu arteritis • On the basis of the sites of
involvement
• Type I – aortic arch and its
branches
• Type II – thoraco-
abdominal aorta and its
major branches
• Type III - Combination of
type I and II
• Type IV – any portion of
the aorta with its branches
+ pulmonary artery.
• {source: Grainger}

81. Preferred Examination
• Angiography - criterion-standard imaging
• CTA and MRA : Of late have become equally valuable tools.

82. • Advantages of CTA and MRA over
conventional angiography:
• large fields of view
• noninvasive nature
• intravenous rather than intra-
arterial contrast material
• increasing resolution of MDCT.
• Particularly useful in pediatric
groups who are poor
candidates for conventional
angiography.
• Advantages of MRI over CT
• Better soft-tissue contrast-
valuable in differentiating
active versus quiescent forms
of Takayasu disease.
• No use of ICM

83. Imaging Findings
• Angiography: The angiographic features occur late in the course
of the disease and include
oluminal irregularity
o vessel stenosis, occlusion, dilatation, or aneurysms in the aorta
or its primary branches.
• CTA and MRA- thickened wall of aorta with crescents and
indistinct outlines
• Associated aneurysms may be saccular or fusiform.
• USG/Doppler study in accessible vessels. Shows wall thickness and
stenosis.

84. Aortogram of a 15-year-old girl with Takayasu arteritis. Note large
aneurysms of descending aorta and dilatation of innominate artery

85. Coronal MRI of abdomen of 15-year-old girl with Takayasu arteritis. Note
thickening and tortuosity of abdominal aorta proximal to kidneys.

86. Intervention
• Corticosteroid- acute phase
• Bypass graft surgery is the procedure with the best long-
term patency rate
• Percutaneous angioplasty:
• C/I in acute phase.
• Best results with short-segment stenosis.
• Stents

88. References
• Textbook of radiology and imaging-David Sutton
• CT and MRI of the whole body-John R. Haaga
• Fundamentals of diagnostic radiology-William E.Brant
• Https://Radiologykey.com//thoracicaortic-aneurysms
• Takayasu arteritis: imaging spectrum at multidetector CT
angiography; F P ZHU et al.; British Journal of Radiology; 2012.
• Acute Traumatic Aortic Injury: Imaging Evaluation and Management;
Scott D. Steenburg;RSNA; 2008:248; 3.