Spontaneous Convexity Subarachnoid Hemorrhage Caused by Internal Carotid Occlusion: Radiological Features

A 79-year-old patient was admitted to the emergency room with transitory monoparesis in the left hand and dysphasia. The brain computed tomography (CT) and magnetic resonance imaging (MRI) showed a spontaneous right convexity subarachnoid hemorrhage (cSAH). Digital subtraction angiography (DSA) confirmed an asymptomatic occlusion of the right internal carotid artery (ICA) . Cases related to stenosis have already been described, but there is no similar report of a case related to occlusion, even though the pathophysiology of both entities is similar. Atraumatic SAH has been associated with intracranial and extracranial artery stenosis.

Agenesia de artéria carótida interna / Agenesis of the internal carotid artery

A agenesia de carótida interna é uma anomalia rara. Na maioria dos casos, é assintomática devido às anastomoses que podem estar presentes, mas pode estar associada a complicações, principalmente quando evidenciada a presença de outras alterações anatômicas ou doença aterosclerótica grave. Relatamos o caso de uma paciente feminina de 63 anos, hipertensa e diabética, com história de cirurgia prévia para clipagem de aneurisma cerebral. Na investigação através de eco-Doppler e angiotomografia de carótidas e vertebrais, foi evidenciada agenesia unilateral da artéria carótida interna esquerda. Este relato objetiva chamar atenção para a importância de se suspeitar de malformações vasculares durante a investigação de quadros neurológicos. A agenesia de carótida interna tem uma importante associação com aneurismas intracerebrais, e é possível poupar o paciente de graves complicações quando estes são identificados a tempo

Agenesis of the internal carotid artery is a rare anomaly. It is usually asymptomatic because of the presence of anastomoses, but it can be associated with complications, especially when there is evidence of other anatomical abnormalities or severe atherosclerotic disease. We report the case of a 63-year-old female patient with hypertension and diabetes and a history of intracranial aneurysm clipping. Doppler ultrasonography and computed tomography angiography of the carotid and vertebral arteries showed unilateral agenesis of the left internal carotid artery. Thisreport aims to highlight the importance of suspecting vascular malformations during investigation of neurological conditions. Internal carotid agenesis has a significant association with intracranial aneurysms and their early detection can spare the patient serious complications

Anomalous External Carotid Artery-Internal Carotid Artery Anastomosis in Two Patients with Proximal Internal Carotid Arterial Remnants

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.

Bilateral internal carotid artery agenesis: a case report / Agenesia bilateral de artéria carótida interna: relato de caso

Agenesis of the internal carotid artery (ICA) is defined as a congenital absence of the carotid canal and occurs in less than 0.01% of the population. This anomaly is usually diagnosed as an incidental finding or after a cerebrovascular event. We present the case of a 36-year-old woman, with bilateral agenesis of the ICA who had suffered a subarachnoid hemorrhage due to ruptured aneurysm of the basilar artery. Therefore, agenesis of the ICA is a condition that, although rare, should be considered since there is a risk of coexistence with other life-threatening conditions such as aneurysms.

Agenesia da artéria carótida interna (ACI) é definida como uma ausência congênita do canal carotídeo e ocorre em menos de 0,01% da população. O diagnóstico dessa anomalia ocorre geralmente como um achado incidental ou depois de um evento cerebrovascular. Apresentamos o caso de uma mulher de 36 anos, hipertensa e tabagista, com agenesia bilateral de ACI, que abriu quadro com hemorragia subaracnoide decorrente de rotura de aneurisma de artéria de basilar. A agenesia da ACI é, portanto, uma condição que, embora rara, deve ser lembrada por estar associada a outras más formações potencialmente fatais, como os aneurismas cerebrais.

Oclusión unilateral de la carótida interna con flujos reversos en ambas arterias oftálmicas: reporte de un caso / Unilateral internal carotid artery occlusion with bilateral ophthalmic arteries reverse flow: case report

El hallazgo de flujo reverso en una arteria oftálmica a través de la ventana transorbitaria en la evaluación de la oclusión carotidea, complementa el Doppler de vasos de cuello, demostrando la existencia de circulación colateral. En el siguiente caso, un paciente con oclusión carotidea derecha presenta flujo reverso en ambas arterias oftálmicas.

The missed missing hole / Revelações de um canal ausente

At times in clinical neurology, the identification of a subtle clinical or radiological sign can lead to prompt diagnosis of a very rare or difficult case. We report on a patient who presented with untreatable headache and unilateral ptosis. Computed tomography (CT) scan of the head did not reveal any structural cause. Magnetic resonance angiogram showed absence of left internal carotid artery, which was eventually confirmed by a catheter angiography. Reviewing the case, it emerged that a feature on the initial CT scan "bone window" would have confirmed the diagnosis, had it been searched for: the underdeveloped carotid canal, which is a consequence and a marker of internal carotid artery agenesis.

Em algumas circunstâncias, o reconhecimento de um sinal clínico ou radiológico sutil pode tornar simples o diagnóstico de um caso raro ou muito difícil em neurologia clínica. Relatamos o caso de uma paciente que apresentava cefaleia intratável e ptose palpebral unilateral. A tomografia computadorizada (TC) de crânio não permitiu identificar nenhuma causa estrutural. A ressonância magnética evidenciou ausência da artéria carótida interna esquerda, posteriormente confirmada por arteriografia convencional. Retrospectivamente, descobriu-se que um dado da janela óssea da primeira TC de crânio teria confirmado o diagnóstico, tivesse ele sido pesquisado: o hipodesenvolvimento do canal carotídeo, que é uma consequência e um marcador de agenesia da artéria carótida interna.

Congenital hypoplasia of the internal carotid artery.

A newborn presented at 14 hrs of age with right sided clonic seizures and shrill cry. Magnetic Resonance Imaging of the brain showed left cerebral hemiatrophy with cystic changes in left fronto-parietal lobe and parasylvian region. The Magnetic Resonance Angiography revealed hypoplasia of left supraclinoid Internal Carotid Artery and hypoplasia and irregularity of vessel wall affecting the left Middle Cerebral Artery. Such an early presentation of this rare disorder has not been reported previously. Recognition of this anomaly has important implications during carotid and trans-sphenoidal surgery, in thromboembolic disease, and in the surveillance and detection of associated cerebral aneurysms.

Persistent trigeminal artery: angio-tomography and angio-magnetic resonance finding / Artéria trigeminal persistente: achado na angio-tomografia e angio-ressonância magnética

The trigeminal artery (TA) is the most common embryonic carotid-vertebrobasilar anastomosis to persist into adulthood. It typically extends from the internal carotid artery to the basilar artery. Persistent primitive arteries are usually found incidentally, but are often associated with vascular malformation, cerebral aneurysm and, in case of TA, with trigeminal neuralgia. We present one patient with TA as a cause of trigeminal neuralgia and in other three as an incidental finding, on TC and MR angiograms.

Artéria trigeminal (AT) é a anastomose carótido-vertebrobasilar mais comum a persistir na vida adulta. Tipicamente estende-se da artéria carótida interna até a artéria basilar. Artérias primitivas persistentes são usualmente um achado incidental, mas freqüentemente estão associadas a malformações vasculares, aneurismas e, no caso da AT, a neuralgia do trigêmio. Apresentamos um paciente com AT como causa de neuralgia do trigêmio e em outros três como um achado incidental, em angiogramas por tomomografia computadorizada e ressonância magnética.

Carótida interna retrofaríngea: relato de caso / Retropharyngeal internal carotid artery: case report

Introdução: Anomalias no trajeto das artérias carótidas podem gerar protrusões faríngeas, para as quais o otorrinolaringologista deve estar sempre atento. Objetivo: Descrever um caso de abaulamento orofaríngeo causado por anomalia vascular no trajeto da carótida interna, com revisão da literatura. Relato do Caso: Paciente de 73 anos, sexo feminino, apresentou-se com queixas de bolo cervical e disfonia intermitente. Ao exame, foi evidenciado abaulamento pulsátil em orofaringe à direita, associado aos sinais laringoscópicos de refluxo faringo-laríngeo. Solicitada tomografia computadorizada de faringe, que mostrou carótida interna tortuosa em espaço retrofaríngeo. A paciente foi encaminhada ao cirurgião vascular que, após Doppler de carótidas, que não revelou obstrução significativa, optou por conduta expectante. Os sintomas faríngeos cederam com o tratamento anti-refluxo. Comentários Finais: Anomalias vasculares da carótida interna devem ser sempre lembradas no diagnóstico diferencial de abaulamentos da parede faríngea.

Introduction: Variations to the course of carotid arteries may lead to abnormal pharyngeal protrusions, to which the otorhinolaryngologist should always attentive. Objective: To report a case of abnormal pharyngeal protrusion due to vascular anomaly in the course of the internal carotid artery, with literature review. Case Report: A 73- year-old woman complained of globus pharyngeus and intermittent dysphonia. A pulsating convexity was observed at the right part of the oropharynx, associated to laryngoscopic signals of pharyngo-laryngeal reflux. The pharyngeal computed tomography scan showed an abnormal tortuous internal carotid in the retropharyngeal space. The patient was sent to the vascular surgeon, who, after a normal blood flow finding at the Doppler, opted for an expectation conduct. The pharyngeal symptoms improved with the antireflux treatment. Final Comments: Internal carotid vascular anomalies must always be recalled in the pharyngeal wall convexity differential diagnosis.

Right internal carotid artery agenesis.

Congenital absence of one or both carotid arteries is a rare anomaly. It is usually discovered incidentally by computed tomography, or magnetic resonance imaging of head and neck taken for some other reason. Most of the patients are asymptomatic, although there is a close association of intracranial aneurysms and subarachinoid hemorrhage in many patients. Here we report a case of right internal carotid agenesis in a young female associated with recent onset amnestic syndrome.

Agenesis of the internal carotid artery: a case report / Agenesia da artéria carótida interna: relato de caso

Relata-se, aqui, caso de uma adolescente de 14 anos de idade que apresentou episódio isolado de síncope, sem outros sintomas. No exame de ressonância magnética observou-se, nos cortes nos planos axial e coronal ponderados em T2, ausência do flow void da artéria carótida interna direita na sua porção intracavernosa. Realizou-se, então, angiorressonância magnética técnica time-of-flight, que mostrou ausência da artéria carótida interna direita, o que foi comprovado com a angiorressonância magnética de vasos cervicais e com angiotomografia computadorizada, que mostrou, nos cortes axiais, agenesia do canal carotídeo direito. Tal achado é relatado na literatura, em associação com outras anomalias, como encefaloceles transesfenoidais e aneurismas do polígono de Willis. No presente caso, não foram observadas tais associações. A paciente permaneceu assintomática.

The present paper reports a case of a 14-year-old-female adolescent who presented a single episode of syncope, without any other symptom. Axial and coronal T2-weighted magnetic resonance imaging demonstrated an absent right internal carotid artery flow void. A subsequent magnetic resonance angiography utilizing the time-of-flight technique showed absence of the right internal carotid artery. This finding was confirmed by magnetic resonance angiography of the cervical vessels, and axial computed tomography angiography showed agenesis of the right carotid canal. The literature reports such finding in association with other anomalies such as transsphenoidal encephaloceles and circle of Willis aneurysms. These associations were not observed in the present case. The patient remained asymptomatic.

Intracranial intrasellar kissing carotid arteries: case report

Intracranial "kissing" carotid arteries are a rare variant of the carotid arteries, where both internal carotid arteries deviate medially and touch each other near the midline within the sphenoid sinus or the sphenoid bone, including the sella. This anomaly is particularly important since it may cause or mimic pituitary disease and also may complicate transsphenoidal surgery. We report a rare case of intracranial intrasellar kissing carotid arteries in a 57-years-old woman that was submitted to a computed tomography angiography during investigation of a sudden headache, and to discuss the clinical relevance of this radiological finding.

Artérias carótidas intracranianas "que se beijam" representam rara variação da anatomia arterial, onde ambas as artérias carótidas internas desviam-se medialmente e tocam-se próximo à linha media dentro do seio esfenoidal ou do osso esfenóide, incluindo a sela túrcica. Essa anomalia é particularmente importante, pois pode causar ou simular doença pituitária e ainda pode complicar uma cirurgia transesfenoidal. Relatamos um raro caso de artérias carótidas intracranianas "que se beijam" em mulher de 57 anos, a qual foi investigada por angiotomografia por quadro de cefaléia súbita. Discutimos a relevância clínica desse achado radiológico.

Association between Internal Carotid Artery Morphometry and Posterior Communicating Artery Aneurysm

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.