Neurol Med Chir (Tokyo) 44, 372¿375, 2004

Middle Cerebral Artery Thrombolysis Through the
Contralateral Internal Carotid Artery
—Case Report—
Ryuzaburo KANAZAWA, Shushi KOMINAMI, Yoichi YOSHIDA,
Shiro KOBAYASHI, and Akira TERAMOTO
Department of Neurosurgery, Nippon Medical School, Tokyo

Abstract
A 63-year-old male presented with sudden onset of right hemiplegia and global aphasia. On admission
he was stuporous. Computed tomography (CT) revealed no abnormalities except for right intraventricular meningioma found incidentally. Emergency angiography confirmed complete occlusion of the left
internal carotid artery (ICA) and left M1 trunk whereas the left ICA bifurcation remained patent. The
ipsilateral ICA was permanently occluded with two detachable balloons to prevent thrombus migration
into the distal ICA and middle cerebral artery (MCA), followed by thrombolysis of the clot in the
ipsilateral M1 through the contralateral ICA with urokinase (total dose 420,000 U) under systemic
heparinization. Partial recanalization of the ipsilateral MCA was accomplished. The time interval from
onset to recanalization was about 3 hours. Postoperative CT showed no hemorrhagic transformation.
Slight right paresis and mild motor aphasia persisted 2 months later and he was transferred to a
rehabilitation facility. Thrombolysis of the MCA embolism can be performed through the contralateral
ICA in the presence of ipsilateral ICA occlusion.
Key words: internal carotid artery occlusion,
contralateral internal carotid artery

middle cerebral artery thrombolysis,

Introduction

leg hemiplegia and global aphasia. His medical
history showed hypertension and diabetes mellitus,
and coronary artery bypass grafting for acute
myocardial infarction 10 years before and surgical
clipping for ruptured aneurysm of the anterior
communicating artery (AcomA) one year later.
Computed tomography (CT) on admission demonstrated no clear evidence of hemorrhage or infarction, but detected an intraventricular meningioma
incidentally (Fig. 1). Left common carotid artery
angiography demonstrated total occlusion of the left
ICA from the cervical portion to the carotid siphon
(Fig. 2). Right ICA angiography showed occlusion at
the horizontal portion of the left MCA and good
collateral flow for the territory through the leptomeningeal anastomosis without occlusion of the
left ICA bifurcation. The orifice of the posterior
communicating artery was presumably occluded by
the thrombus, so vertebral angiography was not
performed.
We considered that microcatheter navigation
through the AcomA was feasible and avoidance of
future embolic events in the ICA to MCA was

The prognosis for patients with acute cerebral
embolism in the internal carotid artery (ICA) is
miserable. Angiographical ICA occlusion is considered impossible to treat successfully in most cases
because of the high rate of complications such as
hemorrhagic transformation or difficulty of restoration of the blood flow.5,7,9,11) Rapid disruption or
dissolution of the thrombus in the ICA is very
difficult. We treated a patient admitted with acute
profound stroke, caused by permanent ipsilateral
ICA occlusion, by intracranial arterial thrombolysis
in the ipsilateral middle cerebral artery (MCA) using
a catheter passed through the contralateral ICA.

Case Report
A 63-year-old, right-handed man presented to our
emergency room 30 minutes after the onset of
stroke. He was stuporous with right face, arm, and
Received

August 4, 2003;

Accepted

March 8, 2004

372

Contralateral Approach for Thrombolysis

Fig. 1

Initial computed tomography scans showing no abnormality such as sulcal effacement, mass effect, edema, or possible
hemorrhage.

Fig. 3

Fig. 2

373

Emergency angiogram revealing thrombus
in the left internal carotid artery (ICA) and
complete extracranial occlusion (upper left).
Anteroposterior digital subtraction angiograms of the right ICA showing the ICA
terminal segment and M1 segment of the left
middle cerebral artery filling across the
anterior communicating artery and then
abruptly stopping (arrow) (upper right), and
the relatively good leptomeningeal collaterals (lower right). The left ICA was treated
with permanent balloon occlusion to
minimize the risk of recanalization and
possible future embolic events (arrowheads)
(lower left).

Neurol Med Chir (Tokyo) 44, July, 2004

Superselective angiogram of the left M1
segment during thrombolysis through the
contralateral internal carotid artery (ICA)
and
anterior
communicating
artery
(AcomA) showing the microcatheter was
positioned in the left M1 segment across the
AcomA (upper). Anteroposterior digital
subtraction angiogram of the right ICA after
thrombolysis revealing recanalization of
posterior branch of the left middle cerebral
artery with residual thrombus (arrow),
which was not treated (lower).

essential. Therefore, permanent left ICA occlusion
with detachable balloons (Gold valve balloons 9 and
16; MinVasys, Paris, France) was performed (Fig. 2),
followed by thrombolysis of the thrombus in the left
MCA through the contralateral ICA and AcomA to
shorten the operation time and to prevent thrombus
migration to the distal ICA and MCA under systemic
heparinization (5000 U heparin bolus, and then 1000
U/hr) (Fig. 3). The urokinase was infused from distal
site of the occluded segment. The catheter (TRACKER-10; Boston Scientific, Natick, Mass., U.S.A.) and
the guidewire (GT wire; Terumo, Tokyo) were also
used to mechanically push through the clot. Partial
recanalization of MCA was finally achieved 200
minutes after onset by administration of 420,000 U
of urokinase, but the clot in the superior trunk could
not be dissolved (Fig. 3).
At this stage, 2 hours had elapsed from the

R. Kanazawa et al.

374

Fig. 4

Computed tomography scans obtained just
after the treatment (upper row) and the day
after the procedure (lower row) showing the
development of anterior left middle cerebral
artery infarction, but no hemorrhagic
transformation.

beginning of the thrombolysis. Therefore, we
abandoned further thrombolysis for fear of hemorrhagic complication.
His neurological symptom was improved gradually after the procedure and CT showed no hemorrhagic transformation (Fig. 4). Ischemic change in
the left frontal region was shown by CT the day after
the procedure (Fig. 4), but no complications such
as hemorrhagic infarction or cerebral edema were
detected in the postoperative course. He had slight
right paresis and mild motor aphasia 2 months after
the procedure, and he was transferred to a rehabilitation facility. Cerebral blood flow study demonstrated no differences between the bilateral
hemispheres except for the left frontal lesion.

Discussion
Thrombolysis has become commonly used for the
treatment of cerebral embolism. In particular, local
intraarterial thrombolysis of MCA occlusion may
benefit patients with evolving thromboembolic
stroke.5,7,9,11–14) The validity of local intraarterial
thrombolysis for MCA occlusion has been estab-

lished by a controlled clinical trial,4) but the prognosis for patients with profound neurological deficits
and acute ICA occlusion remains dismal.5,7,11) Therefore, the operative indication of ICA thrombolysis is
limited.11) The intraarterial microcatheter technique
can deliver highly concentrated drug and allows
mechanical disruption from proximal site of the
clot, but the procedure is not always successful
because of the time required if the clot is large, and
the clot may migrate to the distal ICA or MCA.
However, conservative treatment leads to tragic
outcomes in most cases,9) so thrombolysis is still the
optimum treatment.
Recently, the catheter has been passed through the
ipsilateral ICA in cases of MCA thrombolysis with
cervical ICA occlusion. The microcatheter was
navigated through the occluded segment up to the
supraclinoid ICA or MCA in four patients with good
collateral flow.9) MCA thrombolysis was successful
after coil embolization of the ipsilateral cervical
ICA. Eight cases of extracranial ICA occlusion with
MCA embolism were treated through the collapsed
lumen of the ICA with good outcomes in half of the
cases.3) ICA occlusion with MCA embolism had
higher recanalization rates and better outcomes
than carotid T occlusion, or embolism of the intracranial ICA bifurcation, suggesting that the type
of occlusion and time for recanalization affected the
outcome. Local intraarterial thrombolysis has
achieved excellent outcomes in cases of extracranial
ICA occlusion,5,7,9,14) but is less efficacious in cases
of carotid T occlusion.5–8,11,14) Five of 12 patients
with carotid T occlusion died, indicating that a good
clinical outcome is the exception.
Thrombolysis was started within 170 minutes of
the onset of symptoms in the excellent clinical outcome group.14) The time elapsed from onset to
treatment as well as good collateral flow are important to attain successful thrombolysis.14) Successful treatment leading to good prognosis in cases of
MCA embolism with ICA occlusion is possible if
there is excellent collateral flow, except in the
presence of carotid T occlusion. ``Excellent or good
collateral flow'' is defined as retrograde filling of the
MCA territory within 5 seconds of the end of
intracarotid injection.14) Good collateralization is
also important.1,2,8,10) Initial assessment of the collateral flow from the contralateral ICA and vertebrobasilar system is essential for determining the
amount of thrombus. If the flow from the A1-AcomA
or posterior communicating artery is adequate, then
treatment of the MCA, the distal ICA, and the A1
segment may be all that is necessary.9)
In the present case, the procedure was commenced at the early stage, the collateral circulation

Neurol Med Chir (Tokyo) 44, July, 2004

Contralateral Approach for Thrombolysis
was good, which enabled the left ICA to be occluded
mechanically, and no carotid T occlusion was
present. The thrombolysis was concentrated on the
clots in the ipsilateral MCA, and the left ICA was
permanently occluded by balloon to minimize the
risk of recanalization causing possible future embolic events and to shorten the time required because of
the amount and extent of thrombus. As a result,
partial recanalization of MCA was achieved in a
short time of about 3 hours. We considered that
these factors led to the good outcome in the present
case.
Thrombolysis in the MCA with an ipsilateral
occluded ICA may be approached through the ipsilateral occluded proximal ICA or through the contralateral ICA. The risk of perforation in a normal
cervical or petrous carotid artery may be lower than
the risk of intracranial vascular perforation, at about
1.25%, but further study is needed to define which
approach is safer.9) The current approach as well as
the approach through the occluded carotid artery
can be considered to treat the clot more rapidly, to
prevent clot migration, and to accomplish a better
outcome. Our approach through the contralateral
ICA may be an effective method of thrombolysis to
reduce the damage of ischemia in a patient with
good collateral flow.

References
1)

2)

3)

4)

5)

Arnold M, Nedeltchev K, Mattle HP, Loher TJ,
Stepper F, Schroth G, Brekenfeld C, Sturzenegger M,
Remonda L: Intra-arterial thrombolysis in 24 consecutive patients with internal carotid artery T occlusions. J Neurol Neurosurg Psychiatry 74: 739–742,
2003
Brandt T, von Kummer R, Muller-Kuppers M, Hacke
W: Thrombolytic therapy of acute basilar artery
occlusion. Variables affecting recanalization and
outcome. Stroke 27: 875–881, 1996
Eckert B, Kucinski T, Neumaier-Probst E, Fiehler J,
Rother J, Zeumer H: Local intra-arterial fibrinolysis
in acute hemispheric stroke: effect of occlusion type
and fibrinolytic agent on recanalization success and
neurological outcome. Cerebrovasc Dis 15: 258–263,
2003
Furlan A, Higashida R, Wechsler L, Gent M, Rowley
H, Kase C, Pessin M, Ahuja A, Callahan F, Clark
WM, Silver F, Rivera F: Intra-arterial prourokinase
for acute ischemic stroke. The PROACT II study: a
randomized controlled trial. Prolyse in Acute
Cerebral Thromboembolism. JAMA 282: 2003–2011,
1999
Gonner F, Remonda L, Mattle H, Sturzenegger M,

Neurol Med Chir (Tokyo) 44, July, 2004

6)

7)

8)

9)

10)

11)

12)

13)

14)

375

Ozdoba C, Lovblad KO, Baumgartner R, Bassetti C,
Schroth G: Local intra-arterial thrombolysis in acute
ischemic stroke. Stroke 29: 1894–1900, 1998
Jahan R, Duckwiler GR, Kidwell CS, Sayre JW, Gobin
YP, Villablanca JP, Saver J, Starkman S, Martin N,
Vinuela F: Intraarterial thrombolysis for treatment
of acute stroke: experience in 26 patients with
long-term follow-up. AJNR Am J Neuroradiol 20:
1291–1299, 1999
Keris V, Rudnicka S, Vorona V, Enina G, Tilgale B,
Fricbergs J: Combined intraarterial/intravenous
thrombolysis for acute ischemic stroke. AJNR Am J
Neuroradiol 22: 352–358, 2001
Kucinski T, Koch C, Eckert B, Becker V, Kromer H,
Heesen C, Grzyska U, Freitag HJ, Rother J, Zeumer
H: Collateral circulation is an independent radiological predictor of outcome after thrombolysis in acute
ischaemic stroke. Neuroradiology 45: 11–18, 2003
Nesbit GM, Clark WM, O'Neill OR, Barnwell SL:
Intracranial intraarterial thrombolysis facilitated by
microcatheter navigation through an occluded
cervical internal carotid artery. J Neurosurg 84:
387–392, 1996
Roberts HC, Dillon WP, Furlan AJ, Wechsler LR,
Rowley HA, Fischbein NJ, Higashida RT, Kase C,
Schulz GA, Lu Y, Firszt CM: Computed tomographic
findings in patients undergoing intra-arterial thrombolysis for acute ischemic stroke due to middle
cerebral artery occlusion: results from the PROACT
II trial. Stroke 33: 1557–1565, 2002
Sasaki O, Takeuchi S, Koike T, Koizumi T, Tanaka R:
Fibrinolytic therapy for acute embolic stroke:
intravenous, intracarotid, and intra-arterial local
approaches. Neurosurgery 36: 246–253, 1995
Sylaja PN, Kuruttukulam G, Joseph S, Gupta AK,
Radhakrishnan K: Selective intra arterial thrombolysis in acute carotid territory stroke. Neurol India 49:
153–157, 2001
Ueda T, Hatakeyama T, Kohno K, Kumon Y, Sakaki
S: Endovascular treatment for acute thrombotic
occlusion of the middle cerebral artery: local intraarterial thrombolysis combined with percutaneous
transluminal angioplasty. Neuroradiology 39: 99–104,
1997
Urbach H, Ries F, Ostertun B, Solymosi L: Local
intra-arterial fibrinolysis in thromboembolic ``T''
occlusions of the internal carotid artery. Neuroradiology 39: 105–110, 1997

Address reprint requests to: R. Kanazawa, M.D.,
Department of Neurosurgery, Nippon Medical
School, 1–1–5 Sendagi, Bunkyo–ku, Tokyo 113–8603,
Japan.
e-mail: ryu＠nms.ac.jp