5. Clinical Features
Cerebral Proliferative
Angiopathy
Moyamoya
Seizure: 45%
Headache: 41%
Focal deficits: 16%
Hemorrhages (12%):
33% single -- 67% recurrent
Prognosis: poor
Infarction: 50-75%
TIA: 50-75%
Seizures, headaches
Hemorrhages
Rare: choreiform, cognitive or
psychiatric changes
Prognosis: variable
If a patient with suspect CPA presents with HEMORRHAGE
consider HEMORRHAGIC ANGIOPATHY
6. More facts about Moyamoya
• 10-20% associated with sickle cell disease, NF-1, Down
Syndrome, previous cranial irradiation
• <10% associated with congenital cardiac anomalies, renal-
artery stenosis, giant cervicofacial hemangiomas,
hyperthyroidism
• Genetic component:
– 10% of Japanese & 6% of US pts have a 1st degree relative
– Associated w/abnormalities in chromosomes 3,6,8, & 17
• None of these associations are seen with CPA
7. Pathology Features
Cerebral Proliferative
Angiopathy
Moyamoya
Altered internal elastic
lamina & smooth
muscle cells
Collagenous thickening
of veins
Intermingled normal
neural tissue
Smooth muscle
hyperplasia
Irregular elastic lamina
No inflamacion
8. CT Features
Cerebral Proliferative
Angiopathy
Moyamoya
Areas of dense contrast
enhancement which may
be focal, lobar or
hemispheric
Collateral deep perforators
& pial vessels (Ivy sign)
Cortical Infarcts
Calcium in old infarcts
Hemorrhage
Cerebellum always nl
Hemorrhage:
Consider Hemorrhagic Angiopathy
9. Hemorrhagic Angiopathy: CT
3 pts with Hemorrhagic Angiopathy show intraparenchymal bleeds.
Hemorrhages are much less common in CPA.
10. Angiography Features (1)
Cerebral Proliferative
Angiopathy
Moyamoya
Intermingled nl brain
parenchyma
No dominant feeders
Fast capillary transit
Transdural blood supply
Late stenosis (ICA, M1-2, A1-2):
39%
Aneurysms (12%)
Mildly enlarged draining veins
Dilated perforating
arteries
Generally bilateral
Spares posterior
circulation arteries
Early stenosis of ICA,
M1 & A1
Aneurysms
11. Angiography Features (2)
Cerebral Proliferative
Angiopathy
Hemorrhagic
Angiopathy
Intermingled nl brain
parenchyma
No dominant feeders
Fast capillary transit
Transdural blood supply
Late stenosis
Aneurysms (12%)
Blush may be focal, lobar or
hemispheric
Low incidence of bleeds
Intermingled nl brain
parenchyma
No dominant feeders
Fast capillary transit
No transdural blood supply
No stenoses
No aneurysms
Small pseudo-tumoral blush;
usually subcortical
High incidence of bleeds
18. Early arterial phase (left) & late arterial phase (right) demonstrates nl size arterial feeders
& slightly early draining veins.
Hemorrhagic Angiopathy: Angiography
19. Moyamoya: angiography,
different stages
Narrowing of ICA, M1, A1 Narrowing of ICA with
“Puff-of-Smoke”,
diminished cortical flow.
Obliteration of ICA,
disappearance of Puff-of-Smoke,
further reduction of cortical flow.
20. MR T2WIs & lateral angiogram show focal CPA in the right frontal lobe.
Cerebral Proliferative Angiopathy :
MR & Angiography
21. Cerebral Proliferative Angiopathy: MR
Source MRA (left) shows multiple hypertrophied arteries, MRA frontal view
(center) shows stenosis of left MCA & CPA, T2WI (right) shows abnormal blood
vessels & gliosis in left hemisphere.
22. Cerebral Proliferative Angiopathy: MR
MRI studies (different pts) show multiple flow voids on T1WI (left), FLAIR (center) &
after Gdt administration (right). Note intermingled normal brain in all pts.
24. Cerebral Proliferative Angiopathy: MR Perfusion
MTT, rCBF & rCBV are increased due to capillary & venous ectasia. In classic brain
AVMs MTT is decreased due to rapid shunting.
CBV CBF MTT
26. Cerebral Proliferative Angiopathy: MR
Perfusion
Lasjaunias P. et al. Cerebral proliferative angiopathy, clinical and angiographic description of an entity different from cerebral AVMs.
Stroke. 2008 Mar: 1-8.
T1WI post Gd, TTP, rCBV & rCBF maps in an 11-year-old girl with headaches
shows left frontoparietal CPA. MRI demonstrate increase CBV & CVF indicating
hypervascularization in lesion & decreased TTP in nidus and surrounding areas
suggesting the ischemic nature of the disease.
30. Moyamoya: Vascular MR
Different patients: MRA shows stenosis of both MCAs & large perforators (left). Center
shows stenosis of left MCA. MR perfusion (right) shows low rCBF in deep regions of
both hemispheres.
31. Treatment
Cerebral Proliferative
Angiopathy
Moyamoya
Targeted embolization
Increase cortical blood
supply:
Synangiogenesis or calvarial
burr holes increase cortical
blood supply by recruiting
additional dural arteries
Antiplatelet Tx
Calcium channel
blockers
Surgery:
Synangiogenesis or
calvarial burr holes
Bypass ECA to ischemic
zone is feasible
32. Hemorrhagic Angiopathy: Response to
Radiation therapy
Pre & Post radiation Tx angiography performed on hemorrhagic angiopathy pts. Pre
images demonstrate pseudo tumoral blush at time of ICH with rapid capillary transity.
Post Tx images show excellent response to irradiation.
Pre Treatment Post Treatment Pre Treatment Post Treatment
33. Conclusions
Both cerebral proliferative angiopathy &
Moyamoya are arterial proliferative conditions
leading to stenoses in proximal vessels.
Both are ischemic arterial conditions.
Proliferative angiopathy and hemorrhagic
angiopathy have to be considered as a group of
disorders different from classical brain AVMs.
34. Conclusions
Treatment of Moyamoya aims to an improvement in
arterial supply by direct (bypass) or indirect
(synangiogenesis or calvarial burr holes)
revascularization techniques.
Proliferative angiopathy pts. can be candidates for
arterial revascularisation treatments. In some instances
they can benefit from targeted embolizations.
Hemorrhagic angiopathy has a rapid response to the
radiotherapy.
35. References
Scott R. et al. Moyamoya Disease and Moyamoya Syndrome. NEJM
2009;360:1226-37.
Bacigaluppi S, Dehdashti AR, Agid R, Krings T, Tymianski M, Mikulis
DJ.Neurosurg The contribution of imaging in diagnosis, preoperative
assessment, and follow-up of moyamoya disease: a review. Neurosurg
Focus. 2009; 26:E3a
Lasjaunias P. et al. Cerebral Proliferative Angiopathy, Clinical and
Angiographic Description of an Entity Different From Cerebral AVMs.
Stroke. 2008 Mar: 1-8.
Paolo Tortori-Donati, Andrea Rossi, C. Raybaud. Pediatric Neuroradiology:
Brain, Head , Neck, and Spine. Springer Berlin Heidelberg New York. 2005.
291-297.
Lasjaunias P, Ter Brugge K.G., Berenstein A. Surgical Neuroangiography.
Volume 3: Clinical and Interventioal Aspects in Children. Springer. 2006:
35-39.
37. Case # 1
Patient presents with
stroke symptom of
less than 2 hours.
Non contrast head CT
was performed and
shows a left dense
MCA (arrow).
38. Following the CT of the head, this CTA was performed :
Do you consider the left MCA to be occluded? This
MIP was interpreted as the MCA being patent.
Case # 1
40. Case # 1
Catheter angiogram
shows dissected left
ICA. There is cross
filling from right
injection to level of
occlusion (arrow).
Pial collaterals supply
territory of left MCA
thus filling it with
contrast.
41. Case # 1- Teaching Point
On the CTA the dense clot-filled M1 segment of
the left MCA appears isodense to contrast filled
arteries.
Collateral filling of the ipsilateral MCA branches to
the distal end of the clot resulted in a CTA that
gave the false appearance being normal.
Catheter angiography confirms these findings. If
CTA findings do not correspond with patient’s
symptoms, additional studies using different
techniques may be needed.
42. Case # 2
Patient complained of left sided hemiplegia
and left facial numbness lasting approximately
1 hour.
CTA was performed, two MIP coronal views are
shown (next slide), no early ischemic findings
were observed.
Vasculature and brain parenchyma were
symmetrical. Both ICAs had calcifications.
44. Case # 2
Immediately after the CT the patient underwent MRA
which shows occluded left ICA but cross filling of left
sided intracranial arteries via the circle of Willis.
45. Re-windowing the coronal and axial MIPs show calcification in
the left ICA (arrow) which confirms occluded artery as seen on
MRA. Note that with narrow window settings (left) the
calcification is not appreciated.
Case # 2
46. Case # 2 – Teaching Point
Primary collateral blood flow created a
symmetrical vascular picture of the distal
brain vessels and the dense intra-arterial
calcification in the left ICA masked the total
vessel occlusion when the CTA was viewed
with narrow window settings.
We have seen similar findings in three other
patients. Wide windows should be used to
avoid this problem.
47. Case # 3
Patient presented with acute left
MCA stroke symptoms.
CTA showed no occlusions; VR images
are shown (next slide).
48. Case # 3
Both MCAs are patent and left A1 segment of the ACA is not
visualized, bone obscures visualization of the petrous portions
of the ICAs. The posterior circulation is not seen entirely.
49. Case # 3
Widening the window (right side image) allows one to see that
the petrous portion of the left ICA (arrow) is narrowed when
compared to the opposite side. This finding is difficult to see
with regular window (left image) settings due to similar
densities at vessel/bone interface.
50. Case # 3
Axial MIPs with wide window settings show narrowed
petrous (arrows) left ICA when compared to right ICA
(arrowhead).
51. Case # 3- Teaching Point
With normal window settings, distinguishing
between adjacent bone and opacified vessel
may be difficult.
Separation of blood vessel/bone interface
necessitates wide window settings.
52. Case # 4
Patient had an acute right posterior
circulation infarct confirmed by non-contrast
head CT.
CTA demonstrated diffuse vascular irregularities
and narrow intracranial vessels.
The basilar artery and both P1 segments were
poorly visualized, VR images are shown (next
slide).
53. VRs of the circle of Willis show a narrowed basilar artery, non
visualization of the PCAs and adequate proximal anterior
circulation.
Case # 4
54. Case # 4
Axial MIPs show apparently complete circle of Willis, noticed
that, however vessel opacification is poor suggesting stenosis
(not seen) leading to poor blood flow to these arteries.
55. Case # 4
MIP axial image shows occlusion of the right ICA.
56. Case # 4- Continuation
Angiography confirmed the severe basilar
stenosis and right ICA occlusion.
Most of the arterial supply to the right cerebral
hemisphere was via right ophthalmic artery
and right PCA and not via the anterior
communicating artery as suspected from the
CTA.
57. Case # 4
Right external carotid artery injection
shows opacification of right MCA territory.
Lateral view of ECA injection
shows opacification of right
MCA territory.
58. Left ICA injection shows poor opacification of the right MCA
territory implying inadequate cross filling through ACommA.
Left vertebral artery injection
shows opacification of right MCA
territory.
Case # 4
59. Left vertebral artery injection
shows opacification of right MCA
territory.
Case # 4
60. Case # 4- Teaching Point
The status of the circle of Willis suggested by
the CTA was misinterpreted because of
patient’s low arterial input of contrast and
non-visualization of the collateral supply by
the right ophthalmic and right posterior
communicator artery.
The degree of narrowing of the basilar artery
was overestimated on CT.
Hemodynamic alterations were thought to be
responsible for the patient’s symptoms.
61. Case # 5
Patient presented with acute stroke symptoms
suggesting involvement of left posterior
circulation. CTA showed left occipital
hypodensity.
Axial MIPs are shown (next slide).
62. Case # 5
The transition between left P1 and P2 segments is not well visualized, but small
distal PCA branches show opacification implying that these arteries are patent
(click for sequential MIPs from CTA).
63. VR images show normal basilar artery. The right vertebral artery is dominant while
there is a vessel in the region of the left sided one. A discrepant finding with
respect to the MIPS is that both PCAs are not seen past their proximal segments on
these images probably due to the fact that they were excluded from the
reformations.
Case # 5
64. Case # 5
Injection into the right subclavian artery shows occlusion of
proximal vertebral artery with recanalization cephalad by
collaterals.
65. Case # 5
The right vertebral artery filled
via muscular collaterals and
there was slow flow to the
basilar artery. The left PCA is
occluded (arrow) past its P2
segment while the right sided
one is patent.
66. Case # 5
Injection into left vertebral artery shows that it ends in PICA
thus the vessel seen on the CTA cannot be the vertebral artery
but is probably a vein draining into the marginal sinus.
67. Case # 5- Teaching Point
Initially, there were discrepant findings between the
MIPs and VR images, the latter showing occlusion of
both PCAs. Catheter angiogram showed occluded
left PCA. Despite visualization of the presumed left
vertebral artery on CTA, angiogram showed it be
occluded. Moreover, the right vertebral was
proximally occluded and recanalized distally. The
static nature of CTA does not allow one to visualize
delay circulation times which may have been related
to patient’s symptoms.
68. Case # 6
Patient presented to the hospital after a
peripheral interventional procedure with signs
of a right MCA infarct. Embolic infarct was
suspected. CTA is shown in next slide.
70. Case # 6
Coronal MIPs show left MCA fenestration (circle) and
incompletely seen right M1 segment but with good opacification
of the ipsilateral sylvian branches.
71. Case # 6
VR images confirm left MCA
fenestration (circle) and
adequate filling of right
MCA despite symptoms
corresponding to that side.
72. Case # 6
Angiogram confirms left fenestration (circle). On the right, there is a similar
fenestration but its superior limb is occluded (arrow) explaining the patients
symptoms.
73. Case # 6- Teaching Point
CTA showed patent right MCA. This artery
was however fenestrated and the superior
limb of the fenestration was occluded
resulting in a basal ganglia/capsular infarction.
The fact that the inferior limb of the
fenestration was patent gave the false
impression that the entire left MCA was
patent. This was suspected and lead to
catheter angiogram and attempted
thrombolysis.
74. Case # 7
Patient presented with posterior circulation
infarct symptoms and CTA showed an unusual
configuration of the top of the basilar artery.
75. Case # 6
Sagittal MIP (left) shows irregular basilar artery termination (arrow). This
finding cannot be confirmed on the VR image (right) as the basilar artery apex
is inseparable from adjacent bone.
76. Case # 6
Catheter angiogram shows clot occluding distal basilar artery.
The definitive diagnosis could be made on CTA and required this
study.
77. Case # 6- Teaching Point
Contrast and/or clot may be of similar density
to bone and inseparable from it on VR images.
This is dependent on window settings and
time of study acquisition. Some times,
changing window setting may solve this
problem but others times the problem may
persist. Suspected defects seen on MIPs may
necessitate confirmation by catheter
angiography.
78. Discussion
• Stroke is the end product of a dynamic cascade of
events that culminates with tissue death.
• CTA information is only a snapshot of entire process.
• CTA may reveal distinct phases of disease process or
patient characteristics that serve as confounding factors
in imaging, such as
– recanalization of prior occlusion
– intra-arterial clot that is as dense as IV contrast
– collateral flow that may be primary or secondary
– symmetrical collateral flow that may be insufficient under
hypoperfusion situations.
79. Discussion
• Technical factors such as slice thickness , type of
reconstructions, suitable window settings and
MIP/VR interactive assessment at the work station
may improve assessment of distal branch occlusion
and intra-vascular densities.
• Keep in mind, when assessing a patient with acute
stroke symptoms, that there is a high likelihood that
chronic findings and/or unusual flow patterns may
be related to the patient’s symptoms.
80. Suggested Image Assessment
• Assess all acquired imaging settings
• Alter window level and center when assessing MIPs and VRs
to find calcifications, clots, dissections and stenoses that
may be either concealed or overestimated
• Assess 3D images dynamically, changing vessel bifurcations
angles
• Keep in mind that you are dealing with a dynamic disease
with possible associated chronic findings;
• Keep in mind that venous and arterial systems may be
contrasted and overlapping
• Look for possible collateral flow
89. GOOD LUCK
SAMIR EL ANSARY
ICU PROFESSOR
AIN SHAMS
CAIRO
elansarysamir@yahoo.com
Global Critical Care
https://www.facebook.com/groups/1451610115129555/#!/groups/145
1610115129555/
Wellcome in our new group ..... Dr.SAMIR EL ANSARY