Agenesis of the left internal carotid artery, common carotid artery and main trunk of the external carotid artery associated with multiple cerebral aneurysms: case report

A case of agenesis of the left internal carotid artery, common carotid artery and main trunk of external carotid artery with multiple cerebral aneurysms is presented. No similar case has been reported before. A 70-year-old man who had severe headache was admitted to the neurological department of Matsuyama Shimin Hospital. On admission he demonstrated nuchal rigidity and motor aphasia. CT scan revealed subarachnoid hemorrhage with intracerebral hematoma in the left temporal area. Right common carotid angiography, bilateral retrograde brachial angiography and aortography demonstrated an agenesis of the left internal carotid artery, common carotid artery and main trunk of external carotid artery with aneurysms of the anterior communicating artery, left middle cerebral artery and basilar tip. And these revealed that the left middle cerebral artery was fed from the basilar artery via the dilated left posterior communicating artery, and the left ophthalmic artery was originated from the left middle cerebral artery. CT of the base of the skull revealed no carotid canal on the left side. We confirmed these findings by operation. The importance of altered hemodynamic forces on the circle of Willis produced by the agenesis of the internal carotid artery and the embryological considerations are discussed.     

"True" aneurysm of the posterior communicating artery as a possible effect of collateral circulation in a patient with occlusion of the internal carotid artery. A case study and literature review.

"True" posterior communicating artery (PCoA) aneurysms are extremely rare. A case of a 63-year-old patient with a ruptured "true" aneurysm of the right PCoA associated with the occlusion of the right internal carotid artery is presented. For nine years before he suffered from subarachnoid hemorrhage, the patient had developed symptoms of transient ischemic attack (TIA) due to the occlusion of the right internal carotid artery. The left vertebral angiogram demonstrated a "true" right PCoA aneurysm and collateral flow from the right posterior communicating artery to the right internal carotid artery. The right internal carotid system was also fed by collateral circulation from the left carotid artery through the anterior communicating artery. Transcranial colour-coded real-time sonography (TCCS) demonstrated increased velocity and turbulent blood flow in both communicating arteries. The patient was operated on and the aneurysm was clipped successfully. This case report suggests that the blood flow disturbances resulting from the collateral circulation through the PCoA could be a conductive factor in the formation and development of the aneurysm. This is the first described case of a "true" aneurysm of the PCoA coexistent with the occlusion of the internal carotid artery.     

Subclavian artery to external carotid artery bypass with saphenous vein graft in the treatment of common carotid artery stenosis

A case of TIAs due to proximal common carotid artery stenosis which was successfully treated with autogenous saphenous vein graft between the subclavian artery and the external carotid artery is presented. A 57-year-old, right handed female was admitted to our hospital for the treatment of left common carotid artery stenosis which was pointed out at a local hospital. She had a 7-years' history of repeated transient right hemiparesis and/or left amaurosis fugax. No neurological deficit was revealed on admission. Angiography showed an 80% irregular stenosis of the left common carotid artery at its origin, hypoplastic A1-portion of the left anterior cerebral artery and hypoplasia of the left posterior communicating artery. No other stenotic lesions were disclosed in a four-vessel study. Several kinds of surgical procedures have been reported for the treatment of common carotid stenotic lesion, in accordance with the site and extension of the lesion and hemodynamic factors. To maintain a sufficient blood flow of the left internal carotid artery, we considered four different operative methods such as (1) endarterectomy of the common carotid artery, (2) subclavian to common carotid artery bypass, (3) subclavian to external carotid artery bypass and (4) subclavian to middle cerebral artery bypass. The first two operative procedures force to clamp the common carotid artery which was the only one feeding artery of the left middle cerebral artery because of poor cross flow in this case. These procedures were thought highly possibly to give rise to cerebral infarction on the left side. The fourth method needs a long graft which has higher risk of bypass occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Coil embolization of a ruptured posterior cerebral artery aneurysm via the internal carotid artery and a posterior communicating artery: a case report

A posterior cerebral artery aneurysm is a rare condition. Various surgical approaches have to be considered for operating on these aneurysms because the position of the aneurysm and the surrounding structures restrict the operative field and render the operation difficult. Recently, endovascular treatments for posterior cerebral artery aneurysms have been reported to provide a good outcome. We present a case of a ruptured posterior cerebral artery aneurysm treated with coil embolization. We adopted endovascular treatment because a large vein of Labbé was expected to restrict the operative field. The internal carotid artery and a fetal-type posterior communicating artery (PCoA) were chosen as the access route because of P1 hypoplasty, and a coaxial guiding system was used because of the tortuous access route. The aneurysm was suitably embolized using Guglielmi detachable coils (GDCs). In a case of posterior cerebral artery aneurysm, we report the usefulness of endovascular treatment performed through the internal carotid artery and a fetal-type PCoA.     

Anterior subtemporal approach for posteriorly projecting posterior communicating artery aneurysms

We report our experience with the anterior subtemporal approach for the posterior communicating artery aneurysm protruding posteriorly. Between 2000 and 2005, seven patients with posterior communicating artery aneurysm were operated on through the anterior subtemporal approach. The approach provided a better view than the pterional approach. This approach seems to be suitable for posteriorly projecting posterior communicating artery aneurysms. The advantages of the anterior subtemporal approach are as follows: (1) It provides a short and a direct trajectory to the aneurysm. (2) Aneurysmal neck and surrounding structures can be easily identified and secured compared with the pterional approach. (3) A previously placed clip for a middle cerebral artery or internal carotid artery aneurysm through the pterional route does not interfere with the clipping surgery for regrown or de novo posterior communicating artery aneurysms.     

Extracranial-intracranial bypass to the proximal posterior cerebral artery and to the proximal middle cerebral artery for multiple occlusive cerebrovascular disease

A 48-year-old man with a multiple occlusive cerebrovascular disease involving both the carotid and the vertebrobasilar systems is reported. Faced with noneffective conservative treatment, a surgical approach was carried out. As the patient had poorly developed posterior communicating arteries, two extracranial-intracranial bypasses were performed for both the carotid and the vertebrobasilar circulations; extracranial-intracranial bypasses with interposed saphenous vein grafts between the left external carotid artery and the proximal segment of the left middle cerebral artery, and between the right external carotid artery and the proximal segment of the right posterior cerebral artery. Advantages, precautions, and techniques of this kind of bypass procedure are discussed.     

Unilateral agenesis of the internal carotid artery in a patient with ruptured aneurysm of the anterior communicating artery; a case report]

This 27-year-old female suffered from subarachnoid hemorrhage. Angiography revealed a ruptured aneurysm of the anterior communicating artery. Unilateral absence of the right internal carotid artery was also demonstrated angiographically. Both the right anterior and middle cerebral arteries were perfused from the left carotid artery via the anterior communicating artery. Absence of the right carotid canal was proved on bone CT. Neuroradiological difficulties in differential diagnosis between agenesis and aplasia of the internal carotid artery were discussed. Subsequently, a diagnosis of adult type unilateral agenesis of the internal carotid artery with collateral circulation was made. The mechanism of association of cerebral aneurysm in patients with agenesis of the internal carotid artery was also discussed. From our experience, abnormal vascular anatomy should be carefully studied prior to direct surgery for a ruptured aneurysm in patients with unilateral agenesis of the internal carotid artery.     

Bilateral agenesis of internal carotid arteries

The authors present angiographic and computed tomographic demonstration of bilateral agenesis of internal carotid arteries. The patient was a seventy-six years old man who had been admitted to our hospital because of right hemisparesis and disorientation. In addition to the left chronic subdural hematoma, computed angiotomography showed the dilated basilar artery and dilated posterior communicating arteries. However, the bilateral internal carotid arteries were not recognized. Burr hole and irrigation were performed, then neurological deficits and symptoms were disappeared. Hematoma was 150 ml. Though axial transverse computed tomograms of base of skull demonstrated the absence of bilateral carotid canals. On aortography, the right common carotid artery and vertebral artery were supplied from the innominate artery and the left common carotid artery and vertebral artery were supplied from the left dilated subclavian artery. Bilateral retrograde brachial angiograms demonstrated the internal carotid circulation, which was supplied through bilateral dilated posterior communicating arteries. Basilar artery was also in a large caliber. Bilateral ophthalmic arteries were opacified from external carotid artery via the middle meningeal artery. Ten cases of bilateral agenesis of internal carotid arteries have been reported previously. The findings of angiograms and computed tomograms on the agenesis of bilateral internal carotid arteries were discussed. This anomaly is important on cerebral hemodynamics and embryology.     

Are infundibular dilatations at risk of further transformation? Ten-year progression of a prior documented infundibulum into a saccular aneurysm and rupture: Case report and a review of the literature

Infundibular dilatations (IFDs) are conical, triangular, or funnel-shaped enlargements at the origin of cerebral arteries, and they are primarily located (7–25%) on the posterior communicating artery (PComA). Progression over time into a saccular aneurysm with a risk of rupture of a previously demonstrated IFD has rarely been reported. We report the case of a 60-year-old female who presented 10 years earlier with a subarachnoid hemorrhage caused by a left internal carotid artery aneurysm rupture. At that time, the carotid angiography showed the left internal carotid artery aneurysm and a right posterior communicating artery infundibular dilatation. Neck clipping for the left internal carotid artery aneurysm was performed and the patient was discharged with no neurological deficit. Ten years later, the patient suffered a second fatal subarachnoid hemorrhage; carotid angiography revealed a right posterior communicating artery aneurysm developed from the previously documented infundibular dilatation with a de novo right anterior choroidal artery aneurysm. This case is another proof of the small but growing number of examples of infundibular transformation over time, as well as their risk of progression into saccular aneurysms and subsequent rupture.     

Proximal ligation of the parent artery for symptomatic tandem stenosis of the extradural internal carotid artery: a case report

A 72-year-old man suffered blindness due to right central retinal artery occlusion. Cerebral angiography revealed tandem stenosis in the cervical, petrosal and cavernous portions of the right internal carotid artery (ICA). Blood flow from the vertebrobasilar artery via the right posterior communicating artery mainly perfused the right cerebral hemisphere. In addition, significant stenosis was observed in the left cervical carotid artery and the origin of the left vertebral artety. First, the patient underwent left carotid endarterectomy and vertebral artery to subclavian artery transposition. Two months later, ligation of the right ICA at its origin was performed. Postoperative course was uneventful and the patient has not experienced further ischemic events. We suggest that proximal ligation of the parent artery is a useful procedure for medically-refractory extradural ICA stenosis when surgical direct revascularization and percutaneous transluminal angioplasty cannot be performed.     

Endovascular coil embolization of a recurrent giant internal carotid artery aneurysm via the posterior communicating artery after cervical carotid ligation: case report.

The case of a 29-year-old man with a giant fusiform aneurysm of the left internal carotid artery (ICA) is presented. The aneurysm, treated by cervical ICA ligation and extracranial-intracranial bypass, recurred 4 years later owing to recruitment of the posterior communicating artery (PCoA). Because of the previous bypass surgery a direct surgical approach was excluded. After an initial failure with balloon embolization, the aneurysm was embolized successfully with occlusive platinum microcoils through the microcatheter navigated into the aneurysm via the enlarged PCoA. Endovascular coil embolization may be useful in the treatment of cerebral aneurysms not amenable to direct surgery or balloon embolization.     

Successful intra-arterial fibrinolysis of the anterior choroidal artery in the acute stage of internal carotid artery occlusion: Case report

A 27-year-old man was admitted to our institution with the sudden development of right hemiparesis and dysarthria beginning an hour after the onset of symptoms on August 9, 1992. The patient was found on admission to have right hemiparesis (2/5), hemihypesthesia, hemianopia, dysarthria; he had transient atrial fibrillation. No abnormalities were detected on computed tomography (CT) scans, and cerebral blood flow studies undertaken following conventional CT scans revealed no low flow regions in the left cerebral hemisphere. But cerebral angiography disclosed an occlusion of the left internal carotid artery with well-developed cross-circulation via the anterior communicating artery and embolus lodged at the level of the anterior choroidal artery. Superselective fibrinolysis using Tracker-18 and 420,000 units of urokinase resulting in complete recanalization of the left anterior choroidal artery without distal migration of the embolus. Immediately after the procedure, his neurologic disturbance underwent complete resolution.

In summary, fibrinolysis could be performed but limited to anterior choroidal artery in a case with an occlusion of the internal carotid artery with well-developed cross-flow via the anterior communicating artery; the patient's neurologic condition may deteriorate suddenly if fibrinolysis is incomplete and the embolus migrates to the internal carotid artery.     

Persistent primitive hypoglossal artery with retrograde flow from the vertebrobasilar system: a case report

The persistent primitive hypoglossal artery (PPHA) is one of the pairs of arterial connections that exist in the human embryo between the developing anterior and posterior circulation. Normally the PPHA arises from the cervical internal carotid artery (ICA) and passes through the hypoglossal canal to join the caudal basilar artery (BA). In most cases the vertebral arteries (VA) are either hypoplastic or aplastic and the posterior communicating arteries (PComA) are absent; thus, the main supply to the posterior circulation comes from the internal carotid via the PPHA in an antegrade fashion. Atherosclerotic plaques in the ICA and PPHA present with ischemic symptoms of both the carotid and vertebrobasilar systems. We report a case of a 53-year-old female who presented with a transient episode of left lower extremity numbness and weakness. Work-up with computed tomography (CT) and magnetic resonance imaging (MRI) showed a small watershed infarct in the right middle cerebral artery (MCA)/posterior cerebral artery (PCA) territory. Diagnostic angiography revealed severe proximal stenosis of the cervical ICA and presence of a PPHA just above the stenosis with retrograde filling from the vertebrobasilar junction to the distal cervical ICA. The patient underwent a carotid endarterectomy with intraoperative EEG monitoring. Intraoperative blood flow measurements were made before and after endarterectomy showing evidence of reversal of blood flow to a normal antegrade fashion. The postoperative angiogram showed resolution of the right ICA stenosis and persistence of the PHA. To our knowledge this is the first case report of a PPHA exhibiting reversal of blood flow from the posterior into the anterior circulation. Awareness of this embryological anomaly and its interaction with acquired atherosclerotic disease will minimize misinterpretation of vascular diagnostic studies.     

Agenesis of the right internal carotid artery with intracerebral hemorrhage: case report

A 45-year-old woman was admitted to our department because of intracerebral hemorrhage. Neurological examination showed upward gaze palsy, right hemihypesthesia including face and nuchal rigidity. CT scan demonstrated a high density spot in the left quadrigeminal plate. Postcontrast CT scan demonstrated an abnormal vessel in the left midbrain. We suspected the presence of an arterio-venous malformation (AVM) and angiography was performed. Left vertebral angiography demonstrated early filling as far as the basal vein of Rosenthal with the contrast medium. However, no nidus suggesting AVM was observed. The right middle cerebral artery was fed via an anastomotic vessel (anomalous posterior communicating artery) from basilar bifurcation. Right carotid angiography demonstrated only the right external carotid artery indicating the absence of the right internal carotid artery. The bone target image of thin slice CT scan of the cranial base also disclosed the absence of the right carotid canal. 123I-IMP SPECT demonstrated no hypoperfusion area in the right cerebral hemisphere. The usefulness of the thin slice CT scan in the cranial base was discussed.     

Construction of a new posterior communicating artery in a patient with poor posterior fossa circulation: technical case report

OBJECTIVE AND IMPORTANCE: The carotid and the vertebrobasilar circulation were connected, effectively creating a new posterior communicating artery (PComA). The excimer laser-assisted nonocclusive anastomosis technique is a new anastomosis technique whereby formerly untreatable patients may be treated with an intracranial artery-to-intracranial artery bypass procedure. This report is the first one in which an angiographically proved patent internal carotid artery-posterior cerebral artery segment P1 bypass is presented. CLINICAL PRESENTATION: Our patient presented with repeated episodes of vertebrobasilar ischemia because of vertebral artery occlusion and stenosis. INTERVENTION: An internal carotid artery-posterior cerebral artery segment P1 bypass procedure was performed. Because the patient experienced transient ischemia in the left cerebral hemisphere at the end of postoperative angiography procedure, no radiological intervention was performed, and the patient refused to undergo a new radiological intervention at a later stage. TECHNIQUES: Both anastomoses were made using the excimer laser-assisted nonocclusive anastomosis technique. CONCLUSION: Intraoperative flowmetry was performed using an ultrasound flowmeter, which disclosed blood flow of 35 ml/min through the bypass. We hope that this new PComA suffices to protect the patient from infarction in the territory of the vertebrobasilar circulation.     

Severe stenosis of the internal carotid artery presenting as loss of consciousness due to the presence of a primitive hypoglossal artery: a case report

BACKGROUND: Symptoms of ischemic attacks in the internal carotid system usually involve focal cerebral dysfunction, i.e., hemiparesis or aphasia. However, an ischemic attack in the vertebrobasilar artery system usually presents with combined symptoms. The variety of manifestations included in the vertebrobasilar profile makes the potential pattern of symptoms considerably more variable and complex than that in the carotid system. Manifestations can include syncope and also vertigo. METHOD AND RESULTS: A 42-year-old woman experienced frequent attacks of faintness with vertigo. Angiography demonstrated severe stenosis of the left internal carotid artery with a persistent primitive hypoglossal artery just distal to the stenosis. The right internal carotid artery was normal and cross circulation through the anterior communicating artery was not well developed. Both vertebral arteries were hypoplastic. The patient underwent carotid endarterectomy and, thereafter the episodes of syncope completely disappeared. CONCLUSION: It was supposed that global ischemia including the brain stem occurred because of stenosis of the left internal carotid artery attributable to the presence of a primitive hypoglossal artery.     

Ruptured internal carotid -posterior communicating artery aneurysm associated with an anomalous hyperplastic anterior choroidal artery and aneurysm: case report

We report a rare case of a ruptured internal carotid-posterior communicating artery (IC-PcomA) aneurysm associated with an anomalous hyperplastic anterior choroidal artery (AchoA) and aneuysm. A 64-year-old woman was admitted to our hospital because of a sudden onset of headache. CT scan showed subarachnoid hemorrhage. Left internal carotid angiograms showed a saccular aneurysm at the IC-PcomA region. Left posterior cerebral artery filling from the fetal type PcomA and an anomalous hyperplastic AchoA originating from the internal carotid artery (ICA) were also revealed. Left vertebral angiograms (Allcock test) revealed the left ICA and an anomalous hyperplastic AchoA via the fetal type PcomA. The patient was surgically treated through the left pterional transsylvian approach. The ruptured aneurysm was observed at the IC-PcomA region. The unruptured small aneurysm was found on just distal to the ruptured aneurysm. The PcomA and an anomalous hyperplastic AchoA were not observed behind the ICA. To prevent bleeding, the ruptured aneurysm and unruptured small aneurysm were clipped. Postoperative left internal carotid angiograms demonstrated no aneurysm was observed at the IC-PcomA region. The patency of the fetal type PcomA and an anomalous hyperplastic AchoA were preserved. The 7 reported cases of a intracranial aneurysm associated with an anomalous hyperplastic AchoA with our case are reviewed and their neuroradiological and clinical features are discussed.     

Extracranial internal carotid occlusion and coexisting ipsilateral intracranial internal carotid aneurysm

A rare case of extracranial internal carotid occlusion with a coexisting ipsilateral internal carotid aneurysm is reported. A 50-year-old male had a sudden onset of severe headache, vomiting and right motor weakness on May 14, 1984. Two days later the patient was transferred to our hospital. On admission he was alert but presented with nuchal rigidity and right moderate hemiparesis. He had an episode of a blunt head injury 12 years previously, but no history of hypertension, diabetes mellitus or cerebral stroke. A computed tomography revealed mild subarachnoid hemorrhage and mild ventricular dilatation. A cerebral angiography did not demonstrate any aneurysms but it revealed occlusion of the right internal carotid artery at the cervical bifurcation. The repeated angiography on May 31 disclosed a saccular aneurysm arising anteromedially at the level of the junction of the right posterior communicating artery and the internal carotid artery. The cervical internal carotid artery remained occluded at the same site. The middle cerebral artery was supplied through the well-developed posterior communicating artery, and the right anterior cerebral artery was supplied through the anterior communicating artery. Clipping of the aneurysm was attempted but it was forcibly trapped because of premature bleeding on June 5. The right V-P shunt was performed for the progressive ventricular dilatation on June 12. The patient was discharged with no paresis on June 20. It has been well known that the uni- or bilateral carotid occlusion, whatever the origins are, are often associated with cerebral aneurysms.(ABSTRACT TRUNCATED AT 250 WORDS)     

A case of combined reconstruction of extracranial vertebral and carotid artery stenosis

A 67-year-old man was admitted for status epilepticus, right hemiparesis, repeating vertigo and vomiting. Computed tomography showed no abnormality except for slight brain atrophy. Angiogram demonstrated bilateral vertebral artery stenosis at the origin, especially on the left side, and bilateral cervical internal carotid artery stenosis associated with ulceration. Intracranially, bilateral anterior cerebral artery was filled only by right internal carotid artery. Internal carotid artery on both sides did not fill the posterior cerebral artery. From these findings, we thought that both bilateral internal carotid artery and left vertebral artery should be surgically reconstructed. On June 4, 1986, left vertebral transposition to the common carotid artery and left carotid endarterectomy using double-balloon shunt were performed. Waiting for recovery of the general condition, right carotid endarterectomy was carried out on June 27, 1986. Postoperative angiogram demonstrated disappearance of bilateral internal carotid artery stenosis, and good filling of left vertebral artery through left common carotid artery. Postoperative course was uneventful and right hemiparesis gradually improved. Vertigo and vomiting completely subsided. The method and indication of combined reconstruction for extracranial vertebral and carotid artery were discussed.     

Two cases of "steal VBI" with stenosis of the internal carotid artery

Although previous reports have suggested "steal VBI" due to occlusive carotid artery diseases, there have been no reports that clearly define "steal VBI" from the viewpoint of cerebral hemodynamics. The authors presented two cases with "steal VBI" due to severe stenosis of the internal carotid artery. Both patients had well-developed collateral circulation through the ipsilateral posterior communicating artery. Although no occlusive lesion was found in the vertebrobasilar system, blood flow studies revealed impaired hemodynamics in the contralateral occipital lobe, which fact correlated with their neurological deficit, visual field disturbance. Carotid stenting markedly corrected the stenotic lesions, leading to neurological improvement. Follow-up blood studies showed normalization of hemodynamics in the contralateral occipital lobe. The findings strongly suggest that carotid surgery or stenting can improve cerebral hemodynamics in the carotid systems, resolving "steal VBI" due to developed collaterals from the posterior to the anterior circulation.