Download True Posterior Communicating Artery Aneurysm

KOR J CEREBROVASCULAR SURGERY
KISEP
March 2003 Vol. 5, No 1, page 71-3
True Posterior Communicating Artery Aneurysm
- Case Report -
Department of Neurosurgery, Chunchon Sacred Heart Hospital, Hallym University College of Medicine, Chunchon, Korea
Seong-Min Cho, MD, Sung-Min Cho, MD, Yong-Jun Cho, MD and Seung-Koan Hong, MD
ABSTRACT
A case with a true posterior communicating artery aneurysm is reported, who had been managed by early surgical neck clipping and postoperative intensive cares for numerous complications. The small saccular aneurysm was located at the proximal posterior communicating
artery and directed superiorly. A lacunar infarct developed at right anterior thalamus post-operatively, which had resulted probably from the
occlusion of a fine posterior communicating arterial perforator. Aneurysms of the posterior communicating artery itself are saccular or fusiform.
Great cares should be taken in surgical aneurysmal neck clipping to avoid any injury of the perforators and the oculomotor nerve；trapping
of the posterior communicating artery to treat fusiform or wide-necked aneurysms will result in unpredictable outcomes. (Kor J Cerebrovascular
Surgery 5:71-3, 2003)
KEY WORDS：True posterior communicating artery aneurysm·Perforators·Nomenclature.
Introduction
It is a tradition in medical terminology to nominate intracranial aneurysms according to the name of the arterial branch
adjacent to the neck of the aneurysm. The posterior communicating artery (PCoA) aneurysms are actually internal carotid artery (ICA) aneurysms that develop at the junction of
the ICA and the PCoA.
The authors report a case with a ‘true PCoA aneurysm’, i.
e. an aneurysm of PCoA itself, they had a chance to manage,
review the medical literature, and discuss on the clinical implications of these aneurysms.
Case Report
This 57-year old woman had chronic hypertension managed
by oral medications. She suffered from headache 2 weeks
prior to admission to our hospital. She had been admitted in
a local hospital for a week, and discharged when her headache
had relieved; the cause of her headache remained unknown.
논문접수일：2002년 10월 11일
심사완료일：2003년 01월 15일
교신저자：Seung-Koan Hong, Department of Neurosurgery, Chunchon
Sacred Heart Hospital, Hallym University College of Medicine, 153 Kyodong, Chunchon, Korea
Sudden severe global headache recurred spontaneously on
the day of admission, being accompanied by nausea and vomiting. On admission, her blood pressure was 200/110, and
she was lethargic (GCS 14). Her brain computed tomography
(CT) showed diffuse Fisher group III subarachnoid hemorrhage (SAH, Fig. 1). On hospital day (HD) 2, her follow-up
brain CT revealed ventriculomegaly and scanty intraventricular hematoma (IVH). Transfemoral cerebral angiography
(Fig. 2) revealed a superiorly directing 5 mm-sized saccular
aneurysm attached at the proximal part of right PCoA just
apart form the ICA trunk；the right posterior cerebral artery
was fetal type.
1. Operation
Usual right frontotemporoparietal craniotomy and pterional
approach were performed on HD 2. Beginning from opening
the carotid cistern, the neck of the aneurysm and adjacent
normal anatomical structures were dissected and confirmed.
The body of the aneurysmal sac was adhered to the third
cranial nerve, which was carefully separated. A fenestration
type Sugita’s aneurysm clip with 7 mm-long straight blade
was applied across the neck of the aneurysm parallel to the
PCoA with cares not either to cause any parent arterial stenosis or to leave any residual neck unclipped；the ICA was
encircled by the fenestration of the aneurysm clip with its
external size well preserved. Intraoperatively, no PCoA perforators were definitely injured.
71
진성 후 교통 동맥류
Fig. 1. Initial brain computed tomography showing diffuse thick subarachnoid hemorrhage in the basal, sylvian and perimesencephalic cisterns.
Fig. 2. Transfemoral right internal carotid arteriography shows a
superiorly directed, small (ca. 5 mm) saccular aneurysm attached at the proximal part of the right posterior communicating
artery just apart form the internal carotid arterial trunk；the right
posterior cerebral artery was fetal type.
2. Post-operative Course
On post-operative day (POD) 1, she was alert to drowsy；
brain CT showed residual SAH, IVH in the posterior horns
of lateral ventricles and a small low density at right anterior
thalamus. On POD 3, lumbar drain was installed to drain
CSF continuously.
Her post-operative course was very much complicated thereafter. On POD 4, she became stuporous；brain CT showed
IVH and a large right frontal intracerebral hematoma (ICH)
with a remarkable mass effect. Emergency operation was
performed for the removal of ICH, expansion duroplasty and
decompression craniectomy；close observation on the previ-
72 Kor J Cerebrovascular Surgery 5:71-3, 2003
Fig. 3. Post-operative angiography showing a good obliteration of
the aneurysm sac with well preserved internal carotid and posterior communicating arteries.
ously clipped aneurysm revealed no problems. Immediate
post-operative brain CT showed no residual ICH, small ventricles, residual SAH with IVH, and diffuse brain swelling.
Sedation with intravenous anesthetics started and continued
for the following 3 days. Thereafter she suffered from various
complications, i.e. delayed epidural hematoma, infarcts at
right frontal and occipital areas probably due to post-SAH
vasospasm, hydrocephalus, pneumonia and sepsis, and pulmonary thromboembolism, which were managed intensively.
Post-operative angiography on POD 101 showed a good obliteration of the aneurysm sac (Fig. 3). Around post-SAH day
127 when she was clinically stable, cranioplasty was performed with an autologous bone flap stored in the bone bank
Seong-Min Cho・Sung-Min Cho・Yong-Jun Cho・Seung-Koan Hong
(-76℃ deep freezer). Finally she was discharged on HD
153 with such residual deficits as diplopia due to the medial
gaze palsy of her left eye and left hemiparesis for out patient
departmental (OPD) follow up.
Discussion
Poppen firstly described 2 surgically proven cases of true
PCoA aneurysm.7) Yoshida is known to have firstly nominated
a PCoA aneurysm 2-3 mm apart from ICA-PCoA junction
as ‘true’ PCoA aneurysm in 1979.9) The authors could find a
domestic report of a similar case4) as well as several international reports.1-3)5)6)8)9) Its incidence is reported to be 0-3.3%
of all intracranial aneurysms, and 4.6-11% of so-called
PCoA aneurysms.4)
True PCoA aneurysms have been reported to be located
close to the ICA, at the middle part of PCoA, or close to the
posterior cerebral artery,8) in the order of decreasing frequency.
These aneurysms were not always easily differentiated
from ICA-PCoA aneurysm on pre-operative angiograms and
occasionally identified only in surgical fields.
Muneda et al analyzed 21 cases reported theretofore to
find that true PCoA aneurysms are directed inferiorly, posteriorly, or laterally.6) Other authors reported that the majority
of true PCoA aneurysms are directed laterally and recommended to be very careful in surgical neck clipping of such
laterally directed lesions to avoid intraoperative premature
rupture of the aneurysm or the third nerve injury.4) Kudo
reported a case of true PCoA aneurysm with post-operative
third nerve palsy.5) In the majority, the aneurysm could be
surgically secured successfully.1-4)6)8)9)
The authors agree with other previous authors’ descriptions
that every effort should be made in the surgical neck clipping
to preserve all fine perforators branching off the PCoA in
order to prevent the possible occurrence of post-operative
small thalamic, hypothalamic, or basal ganglial infarcts. This
important principle pertains to such cases with superiorly
directed lesions as this patient.
Kamiyama reported transient emotional disturbance,3) and
Abiko & Orita reported mental deterioration, contralateral
hemiplegia, ipsilateral third nerve palsy, and ipsilateral basal
ganglial hemorrhagic infarct after trapping of PCoA performed to treat a true PCoA fusiform aneurysm,1) respectively.
Muneda et al wrote that it is difficult to predict the possibility
of post-operative ischemic complications when the PCoA is
trapped for the treatment of fusiform or wide-necked lesions.6)
Conclusion
A rare case with a ruptured true PCoA aneurysm is reported.
The majority of these aneurysms can be surgically secured
with successful clinical results. Much cares should be taken
in surgical neck clipping of these aneurysms to avoid any
injury of PCoA perforators and the third cranial nerve.
REFERENCES
1) Abiko S, Orita T. A case of “true” posterior communicating artery
aneurysm. No Shinkei Geka 9:1181-5, 1981
2) Akimura T, Abiko S, Ito H. True posterior communicating artery
aneurysm. Acta Neurol Scan 84:207-9, 1991
3) Kamiyama K, Sakurai Y, Suzurai J. Aneurysm of posterior communicating artery itself-report of a successfully treated case. Neurol Med
Chir(Tokyo) 20:81-4, 1980
4) Kang SD. True posterior communicating artery aneurysm. J Korean
Neurosurg Soc 26:1007-10, 1997
5) Kudo T. An operative complication in a patient with a true posterior
communicating artery aneurysm: case report and review of the literature. Neurosurgery 27:650-3, 1990
6) Muneda K, Yoshizu H, Terada H. True posterior communicating artery aneurysm. No Shinkei Geka 29:163-8, 2001
7) Poppen JL. Specific treatment of intracranial aneurysms: Experiences
with 143 surgically treated patients. J Neurosurg 8:75-102, 1951
8) Takeda N, Tamaki N, Asada M, Kurata H, Matsumoto S. ‘True’ posterior communicating artery aneurysm presenting the abducens nerve
palsy. No Shinkei Geka 13. 1331-4, 1985
9) Yoshida M, Watanabe M, Kuramoto S. ‘True’ posterior communicating artery aneurysm. Surg Neurol 11:379-81, 1979
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