PURPOSE: The goal of this study was to directly measure the association between the internal carotid artery (ICA) morphometry and the presence of ICA-posterior communicating artery (PCOM) aneurysm. MATERIALS AND METHODS: The authors intraoperatively measured the length of the supraclinoid ICA because it is impossible to radiologically determine the exact location of the anterior clinoid process. We used an image analyzer with a CT angiogram to measure the angle between the skull midline and the terminal segment of the ICA (ICA angle), as well as the diameter of the ICA. The lengths and diameters of the supraclinoid ICA and the ICA angle were compared among PCOM aneurysms, anterior communicating artery (ACOM) aneurysms, and middle cerebral artery (MCA) bifurcation aneurysms (n=27 each). Additionally, the lengths and the diameters of M1 and A1 were compared for each aneurysm. RESULTS: The lengths of the supraclinoid ICA were 11.9+/-2.3mm. The lengths of the supraclinoid ICA in patients with ICA-PCOM aneurysms (9.7+/-2.8mm) were shorter than those of patients with ACOM aneurysms (13.8+/-2.2mm, Student's t-test, p<0.001) and with MCA bifurcation aneurysms (12.2+/-1.9 mm, Student's t-test, p<0.001). The diameters of the supraclinoid ICA and A1 in patients with ACOM aneurysms were larger than those in patients with MCA bifurcation aneurysms (Student's t-test, p<0.05). There were no significant differences in the lengths of M1 and A1, ICA angle, or diameter of M1 for each aneurysm. CONCLUSION: These results suggest that the relatively shorter length of the supraclinoid ICA may be a novel risk factor for the development of ICA-PCOM aneurysm with higher hemodynamic stress.
Carotid Artery Diseases/congenital/*radiography ; Carotid Artery, Internal/abnormalities/*radiography ; Humans ; Intracranial Aneurysm/*radiography ; Risk Factors

PURPOSE: This study aimed to investigate the luminal stenosis of the internal carotid artery with calcification detected on panoramic radiographs. MATERIALS AND METHODS: This study used fifty carotid arteries of 36 dental patients whose panoramic radiograph and computed tomography angiography (CTA) revealed the presence of carotid artery calcification. A neuroradiologist interpreted CTA to determine the degree of stenosis of the internal carotid arteries. The degree of stenosis was stratified in four stages; normal (no stenosis), mild stenosis (1-49%), moderate stenosis (50-69%) and severe stenosis (70-99%). RESULTS: Among the fifty carotid arteries with calcification detected on both panoramic radiography and CTA, 20carotid arteries (40%) were normal, 29 carotid arteries (18%) had mild stenosis, 1 carotid artery (2%) had moderate stenosis, and there was none with severe stenosis. CONCLUSION: Sixty percent of the carotid arteries with calcification detected on both panoramic radiography and CTA had internal luminal stenosis, and two percent had moderate stenosis. When carotid atheroma is detected on panoramic radiograph, it is possible that the dental patient has luminal stenosis of the internal carotid artery.
Angiography ; Arteries ; Carotid Arteries ; Carotid Artery, Internal ; Constriction, Pathologic ; Humans ; Phenobarbital ; Plaque, Atherosclerotic ; Radiography, Panoramic

*Abnormalities, Multiple/radiography ; Basilar Artery/*abnormalities ; Basilar Artery/radiography ; Carotid Artery, Internal/radiography ; Intracranial Aneurysm/*complications ; Intracranial Aneurysm/radiography ; Vertebral Artery/radiography

Two angiographic instances of anomalous external carotid artery (ECA) and internal carotid artery (ICA) anastomosis are described, each occurring at the C2-3 level and bearing remnants of proximal ICA. The ICA remnant of one patient (identifiable immediately upon bifurcation of the common carotid artery) was hypoplastic, and that of the other patient was an occluded arterial stump. These features are not typical of non-bifurcating ICA. The occipital artery originated from an anomalous connection in one instance and from the main trunk of the ECA (just past the ECA-ICA connection) in the other.
Adult ; Arterial Occlusive Diseases/radiography ; Carotid Artery, External/*abnormalities/radiography/surgery ; Carotid Artery, Internal/*abnormalities/radiography/surgery ; Cerebral Angiography ; Humans ; Intracranial Aneurysm/*radiography/surgery ; Male ; Middle Aged

Extracranial carotid artery dissection may manifest as arterial stenosis or occlusion, or as dissecting aneurysm formation. Anticoagulation and/or antiplatelet therapy is the first-line treatment, but because it is effective and less invasive than other procedures, endovascular treatment of carotid artery dissection has recently attracted interest. We encountered two consecutive cases of traumarelated extracranial internal carotid artery dissection, one in the suprabulbar portion and one in the subpetrosal portion. We managed the patient with suprabulbar dissection using a self-expandable metallic stent and managed the patient with subpet-rosal dissection using a balloon-expandable metallic stent. In both patients the dissecting aneurysm disappeared, and at follow-up improved luminal patency was observed.
Adult ; Carotid Artery Injuries/complications ; Carotid Artery, Internal, Dissection/etiology/radiography/*therapy ; Case Report ; Cerebral Angiography ; Human ; Male ; *Stents

Abnormalities, Multiple ; diagnostic imaging ; Basilar Artery ; abnormalities ; diagnostic imaging ; Carotid Artery, Internal ; diagnostic imaging ; Humans ; Intracranial Aneurysm ; complications ; diagnostic imaging ; Male ; Middle Aged ; Radiography ; Vertebral Artery ; diagnostic imaging

A 44-year-old woman who showed recurrent vitreous hemorrhages with vascular tortuosity received CT angiography which revealed an internal carotid artery aneurysm. A case of internal carotid aneurysm was associated with a pattern of retinal arteriolar tortuosity pathognomic for familial retinal arterial tortuosity (fRAT), suggesting possible involvement of the cerebral circulation. We present a case of internal carotid aneurysm associated with a pattern of retinal arteriolar tortuosity pathognomic for fRAT.
Adult ; Aneurysm/*complications/radiography ; Angiography ; Carotid Artery Diseases/*complications/radiography ; *Carotid Artery, Internal ; Diagnosis, Differential ; Eye Abnormalities/complications/diagnosis/*genetics ; Female ; Follow-Up Studies ; Humans ; Retinal Artery/*abnormalities ; Tomography, X-Ray Computed ; Torsion Abnormality/complications/diagnosis/*genetics ; Visual Acuity

Rapid arterial rethrombosis is associated with high-grade residual stenosis and usually occurs at the site of the initial occlusion, resulting in reocclusion of the recanalized artery. Platelets may play an active role in such rethrombosis after thrombolytic-induced clot lysis. Given that glycoprotein IIb/IIIa receptor blockers, like tirofiban, prevent thrombus formation by inhibiting the final common pathway of platelet aggregation, they may be helpful for treating rethrombosis after thrombolysis. A 64-year-old man presented with an acute ischemic stroke due to internal carotid artery (ICA) occlusion. The ICA was recanalized by intravenous thrombolysis but reoccluded shortly after recanalization. The reoccluded ICA was successfully recanalized using intra-arterial tirofiban. A carotid stent was subsequently inserted to relieve severe stenosis and to prevent recurrent stroke. Here, we report a case of rescue treatment of a successfully recanalized ICA by intra- arterial tirofiban. We suggest that rescue use of intra-arterial tirofiban may be effective and safe, especially in hemorrhage prone situations, due to the relatively lower dose of tirofiban compared with intravenous doses.
*Carotid Artery, Internal ; Carotid Stenosis/*drug therapy/radiography/surgery ; Emergency Treatment ; Humans ; Infusions, Intra-Arterial ; Male ; Middle Aged ; Stents ; Tyrosine/administration & dosage/*analogs & derivatives/therapeutic use

Occlusion of the anterior choroidal artery (AChA) can cause infarction in the posterior limb of the internal capsule. Infarction is less frequently observed in the thalamus, midbrain, temporal lobe, and lateral geniculate body (LGB) territories of the AChA. The most common clinical finding is hemiparesis. Hemianesthesia may be severe at onset but is usually transient. Homonymous hemianopia, upper-quadrant anopia, or upper- and lower-quadrant sector anopia can be present. Occasionally these patients are reported to have transient abnormalities of higher cortical function. The most common stroke mechanism is known to be small-vessel occlusive disease, predominantly found in hypertensive and diabetic patients. Vasospasm due to ruptured aneurysm or intraoperative mechanical manipulation, and cardiac origin the AChA territory. The infarct lesion is usually recognized and diagnosed by computed tomography. The best treatment is still unknown.
Aged ; Carotid Artery, Internal/radiography ; Case Report ; Cerebral Angiography ; Cerebral Infarction/*radiography ; Choroid Plexus/blood supply ; Female ; Human ; Male ; Middle Age ; *Tomography, X-Ray Computed

This study was intended to correlate the appearance of the cavernous segment of the carotid artery on MR images with the presence of significant stenosis or occlusion of the cervical carotid artery as seen on angiograms in 37 patients with cerebrovascular disorders who had brain MRI and arteriography. Three patients demonstrated an isointense signal within the carotid artery's cavernous segment, correlating with complete carotid occlusion as seen angiographically. Ten patients had variable signal intensity and/or luminal narrowing in the carotid siphon; seven of these findings correlated with angiographic evidence of carotid occlusion, while carotid branch occlusion was seen angiographically in the other three. The demonstration of normal signal void within a normal-appearing cavernous segment of the internal carotid artery in the remaining 24 patients correlated with an absence of significant stenosis within the cervical segment in 21 patients. In the remaining three, significant disease of the internal carotid artery was found. Isointensity or luminal irregularity within the intracranial carotid artery can indicate complete occlusion or slow flow. The presence of normal flow void in the intracranial segment does not exclude significant abnormality of the cervical segment of the carotid artery.
Adolescent ; Adult ; Aged ; Arterial Occlusive Diseases/diagnosis ; Carotid Artery Diseases/diagnosis ; Carotid Artery, Internal/*radiography ; Carotid Stenosis/diagnosis ; Cerebrovascular Disorders/*diagnosis ; Female ; Humans ; *Magnetic Resonance Imaging ; Male ; Middle Aged ; Predictive Value of Tests ; Retrospective Studies