Anterior Choroidal Artery Aneurysms: Influence of Regional Microsurgical Anatomy on Safety of Endovascular Treatment

Several anatomical variables critically influence therapeutic strategizing for anterior choroidal artery (AChA) aneurysms, and specifically, the safety of flow diversion for these lesions. We review the microsurgical anatomy of the AChA, discussing and detailing these considerations in the treatment of AChA aneurysms, theoretically and in the light of our recent findings.

Anatomía microquirúrgica e irrigación arterial de la región uncal / Microsurgical anatomy and arterial irrigation of the uncal region

El objetivo de este trabajo fue realizar una revisión microquirúrgica de los principales ramos arteriales que otorgan irrigación a la región uncal, identificando sus principales variantes y sus relaciones anatómicas mas relevantes con las estructuras circundantes. Se estudiaron 20 hemisferios cerebrales con el sistema arterial perfundido con latex y colorante mediante disección microquirúrgica y bajo aumento con un rango de 3X a 40X. Se realizaron registros morfométricos de las principales estructuras. La irrigación de la región uncal del lóbulo temporal se establece principalmente por tres grupos de ramas uncales: las ramas uncales anteriores provenientes de la arteria temporopolar que es uno de las ramas colaterales que inicialmente se derivan de la arteria cerebral media en su segmento M1. Ramas uncales mediales provenientes de la arteria coroidea anterior en su trayecto cisternal. Ramas uncales posteriores provenientes de los segmentos P2A y P2P de la arteria cerebral posterior. La relevancia de la descripción vascular arterial de la región uncal radica en la aplicación del conocimiento de estas relaciones y variantes durante los diversos procedimientos diagnósticos y quirúrgicos del lóbulo temporal.

The objective of this work was realizing a microsurgical review of the main arterial ramus that distribute irrigation to the uncal region, identifying the most common variations and more relevant relationships with surrounding structures. Twenty (20) fixed human brain hemispheres were studied, with the arterial latex and red colorant perfusion technique for dissection under microscope magnification (3X-40X). Morphometric characterization and data were obtained of the structures studied. Arterial irrigation of the uncal region of the temporal lobe is established by three groups of uncal ramus: the anterior uncal rami, deriving from the temporopolar artery, which is one of the first branches of the middle cerebral artery in segment M1. The medial uncal rami, branches of the cisternal portion of the anterior choroidal artery. The posterior uncal rami, branches of the P2A and P2P segments of the posterior cerebral artery. The relevance of arterial vascular description of the uncus, results in the application of knowledge of the variations and relationships during the diagnostic and surgical procedures of the temporal lobe.

Usefulness of Motor-Evoked Potentials Monitoring for Neurosurgical Treatment of an Unusual Distal Anterior Choroidal Artery Aneurysm

A 35 years old woman presented with an acute meningeal syndrome following an intra ventricular haemorrhage without subarachnoid haemorrhage. The angiography demonstrated a 6 mm partially thrombosed saccular aneurysm at the plexal point of the right anterior choroidal artery (AChoA). It was surgically approached inside the ventricle through a trans-temporal corticotomy. The aneurysm was excised after distal exclusion of the feeding artery under motor-evoked potentials monitoring. Of the 19 cases of distal AChoA aneurysm neurosurgical treatment, this is the only one performed under electrophysiology monitoring, a simple and safe method to detect and prevent motor tract ischemia. We discuss this rare case, along with a comprehensible review of the literature of the previous surgical cases of distal AChoA aneurysms.

Delayed Ischemic Stroke after Flow Diversion of Large Posterior Communicating Artery Aneurysm

For securing large, giant, and wide-neck aneurysms, conventional coil embolization has substantial limitations, such as incomplete occlusion, recanalization, and a high recurrence rate. To overcome these limitations, a novel paradigm was suggested and, as a result, flow-diverting device was developed. The flow-diverting device is an innovative and effective technique to allow securing of large, giant, and wide-neck aneurysms. In numerous studies, the flow-diverting device has shown better outcomes than coil embolization. However, the flow-diverting device has also some risks, including rupture of aneurysm, intracerebral hemorrhage, and ischemic stroke. In addition, with more experience, unexpected complications are also reported.5) 7) In the present case, we experienced a delayed ischemic stroke at 27 days after endovascular treatment. The patient had multiple aneurysms and, among them, we treated a large posterior communicating artery aneurysm using Pipeline™ Embolization Device. The patient was tolerable for 25 days, but then suddenly presented intermittent right hemiparesis. In the initial diffusion magnetic resonance imaging (MRI), there was no acute lesion; however, in the follow-up MRI, an acute ischemic stroke was found in the territory of anterior choroidal artery which was covered by Pipeline Embolization Device. We suspect that neo-intimal overgrowth or a tiny thrombus have led to this delayed complication. Through our case, we learned that the neurosurgeon should be aware of the possibility of delayed ischemic stroke after flow diversion, as well as, long-term close observation and follow-up angiography are necessary even in the event of no acute complications.

Prominent Cognitive Dysfunction without Motor Impairment Following Anterior Choroidal Artery Infarction: a Case Report

Neurological deficits commonly associated with anterior choroidal artery infarction (AChAI) include hemiplegia, hemisensory loss, and homonymous hemianopsia, while neuropsychological and perceptual deficits are uncommon. Prominent cognitive function impairment has rarely been reported. Here, we report a case of AChAI with prominent cognitive function impairment without motor deterioration. In contrast to the typical clinical features of AChAI, near complete and rapid motor recovery was observed, while cognitive impairment persisted despite rehabilitation therapy.

Infarto de la arteria cerebral posterior secundario a oclusión aguda de la arteria carótida interna / Posterior Cerebral Artery Stroke Secondary to Acute Occlusion of the Internal Carotid Artery

Bases: los principales síntomas del compromiso de la arteria carótida interna son la amaurosis fugax y aquellos que se deben a un compromiso de las arterias cerebral media y anterior. Métodos: se trata de un hombre de 79 años diabético e hipertenso que se presentó con un cuadro que sugería un compromiso de la arteria cerebral media izquierda. Se documentó una obstrucción aguda de la arteria carótida interna izquierda, con infartos del territorio de la arteria coroidea anterior y la cerebral posterior del mismo lado; en el estudio se halló una fuente cardioembólica. Conclusión: si bien la obstrucción aguda de la arteria carótida interna se asocia sobre todo a síntomas visuales y de compromiso de la circulación anterior, se puede relacionar también con infartos de la arteria cerebral posterior.

Background: the main symptoms of a compromise to the internal carotid artery are monocular blindness and those which are secondary to the lesion of the medial cerebral and anterior cerebral arteries. Methods: a 79 year old male patient, with past medical history of diabetes and high blood pressure and clinical symptoms of compromise to the left medial cerebral artery. The patient shows an acute occlusion of the left internal carotid artery with arterial infarcts in the choroidal anterior and cerebral posterior territories in the same side of the carotid lesion. The cardioembolic source of the infarct was documented. Conclusion: Although acute obstruction of the internal carotid artery is mostly associated with visual symptoms and engagement of the anterior circulation, it may also be associated with infarcts of the posterior cerebral artery.

Blood Blister-Like Aneurysm with Rupture Point Close to Origin of Anterior Choroidal Artery

If a ruptured blood blister-like aneurysm (BBA) arises from the lateral or superolateral wall of the internal carotid artery (ICA) at the level of the anterior choroidal artery (AChA), its proximity to the origin of the AChA presents a serious surgical challenge to preserve the patency of the AChA. Two such rare cases are presented, along with successful surgical techniques, including the application of a C-shaped aneurysm clip parallel to the ICA and a microsuture technique to repair the arterial defect. The patency of the AChA and ICA was successfully preserved without recurrence or rebleeding of the BBA during a 1-year follow-up after the operation.

Demonstration of Traumatic Subarachnoid Hemorrhage from the Anterior Choroidal Artery

We present a case of angiographically confirmed transection of the cisternal segment of the anterior choroidal artery (AChA) associated with a severe head trauma in a 15-year old boy. The initial brain computed tomography scan revealed a diffuse subarachnoid hemorrhage (SAH) and pneumocephalus with multiple skull fractures. Subsequent cerebral angiography clearly demonstrated a complete transection of the AChA at its origin with a massive extravasation of contrast medium as a jet trajectory creating a plume. We speculate that severe blunt traumatic force stretched and tore the left AChA between the internal carotid artery and the optic tract. In a simulation of the patient's brain using a fresh-frozen male cadaver, the AChA is shown to be vulnerable to stretching injury as the ipsilateral optic tract is retracted. We conclude that the arterial injury like an AChA rupture should be considered in the differential diagnosis of severe traumatic SAH.

Anterior Choroidal Artery Aneurysm Surgery: Ischemic Complications and Clinical Outcomes Revisited

OBJECTIVE: Surgical results for anterior choroidal artery (AChA) aneurysms have previously been reported as unsatisfactory due to inadvertent occlusion of the AChA, while the low incidence of AChA aneurysms hampers the accumulation of surgical experience. The authors reviewed their related surgical experience to document the ischemic complications and surgical outcomes. METHODS: Identification of the AChA at its origin by rigorous visual scrutiny, careful microdissection, and meticulous clip placement to avoid the AChA origin are all crucial surgical maneuvers. A retrospective review of a surgical series of 62 consecutive cases of an AChA aneurysm between 2004 and 2012 was performed. RESULTS: All patients, except for five (8.1%) with a small residual neck, showed complete aneurysm obliteration in postoperative angiographic evaluations. There was no incidence of procedure-related permanent AChA syndrome or oculomotor nerve palsy, while three (4.8%) patients suffered from transient AChA syndrome. The clinical outcomes [the 3-month modified Rankin Scale (mRS)] of the patients were related to their preoperative World Federation of Neurologic Surgeons (WFNS) grade. As regards the 3-month mRS, significant differences were found between patients with an unruptured aneurysm (WFNS grade 0; n=20), good-grade subarachnoid hemorrhage (WFNS grade 1-3; n=30), and poor-grade subarachnoid hemorrhage (WFNS grade 4-5; n=4). CONCLUSION: In surgical treatment of AChA aneurysms, a risk of AChA insufficiency can be minimized by taking every precaution to preserve the AChA patency and intraoperative monitoring. In addition, the surgical outcome is primarily determined by the preoperative clinical state.

Incidentally Discovered Direct Carotid-Cavernous Fistula in a Patient With Anterior Choroidal Artery Territory Infarction

Direct carotid cavernous fistula (CCF), which is an abnormal communication between the intracavernous carotid artery and the cavernous sinus, is a very rare condition that is generally associated with head trauma, intracavernous aneurysms, and certain connective-tissue diseases. The case of a patient with an infarction in the anterior choroidal artery territory is described herein. Cerebral angiography was performed during consecutive workups to investigate the discrepancy between the magnetic resonance angiography data. An unexpected direct CCF of the ipsilateral side of the infarction was found. It is possible that the CCF had influenced the development of the infarction in the anterior choroidal artery territory.

Incidentally Discovered Direct Carotid-Cavernous Fistula in a Patient With Anterior Choroidal Artery Territory Infarction

Direct carotid cavernous fistula (CCF), which is an abnormal communication between the intracavernous carotid artery and the cavernous sinus, is a very rare condition that is generally associated with head trauma, intracavernous aneurysms, and certain connective-tissue diseases. The case of a patient with an infarction in the anterior choroidal artery territory is described herein. Cerebral angiography was performed during consecutive workups to investigate the discrepancy between the magnetic resonance angiography data. An unexpected direct CCF of the ipsilateral side of the infarction was found. It is possible that the CCF had influenced the development of the infarction in the anterior choroidal artery territory.

Características biométricas de la arteria coroidea anterior en su segmento cisternal / Biometrical characteristics of anterior choroidal artery in its cisternal segment

Las implicancias clínicas que tienen los procesos oclusivos de la Arteria Coroidea Anterior (AChA), son de considerable importancia y nos han motivado para efectuar su análisis biométrico incorporando algunos otros parámetros. Para su ejecución, se utilizaron cerebros inyectados con látex coloreado de rojo fijados en solución de formol, provenientes del Servicio Médico Legal, Santiago.Para su observación, se usó lupa luminiscente 4 X y las mediciones efectuadas con Caliper Mitutoyo Digital. Esta arteria se originó de la Carótida Interna (ACI) en un 83,3 por ciento y en un 16,7 por ciento de la Arteria Comunicante Posterior (ACoP ). El calibre medio observado en su origen fue de 0,68 +/- 0,31 mm; en el tercio medio de 0,60 +/- 0,21 mm; en el punto de entrada en el plexo coroideo de 0,48 +/- 0,23 mm. La longitud media desde el origen de la AChA al plexo coroideo fue de 28,67 +/-6,33 mm; la distancia media desde su origen al de la ACoP fue de 6,97 +/- 4,89 mm. El número promedio de ramas perforantes registradas fue de 6. Nuestros resultados pueden ser una contribución a considerar en la clínica...

The clinical implications of occlusive processes in the anterior choroidal artery (AChA) are of considerable importance and have motivated us to perform a biometrical analysis of the afore mentioned artery including new biometric parameters (measurements). This study was perfomed on vascularized brains that were both fixed with for formalin solution and injected whith red tinted latex and brains that were not fixed with formalin solution, which were obtained from the Medical Legal Service, Santiago. They were observed using a luminescent 4 X magnifying glass and the measurements perfomed using a Mitutoyo Digital Caliper. This artery originated from the internal carotid artery (ICA) in 83.3 percent of the cases observed, and in 16.7 percent it originated from the posterior communicating artery ( PCoA). The mean caliber (diameter) of the artery was 0.68 +/- 0.31 mm at the point of origin; the middle third was 0.60 mm +/- 0.21 mm; at the point of entry into the choroidal plexus it was 0.48 mm +/- 0.23 mm. The mean length from its origin at the AChA to the choroidal plexus was 28.67 mm +/- 6.33 mm; the mean distance from its origin at the PCoAwas 6.97mm+/- 4.89 mm. The number of perforating branches of the AChA was 6. Our results can be considered a clinical contribution...

Transposition of Anterior Choroidal Artery and Posterior Communicating Artery Origin

The anterior choroidal artery has several kinds of variations. Among them, the transposition of anterior choroidal artery and posterior communicating artery origins has been extremely rare. We report a case with cerebral aneurysm arising from posterior communicating artery which origin was distal to the anterior choroidal artery and review the relevant literature.

Ischemic Complication of Ruptured Anterior Choroidal Artery Aneurysm / 대한뇌혈관외과학회지

OBJECTIVE: Vasospasm is known to play the key role in determining the prognosis of aneurysmal subarachnoid hemorrhage (SAH). We have experienced a higher incidence of vasospasm in the cases of SAH caused by rupture of an anterior choroidal artery (AChA) aneurysm than aneurysms of other area. The purpose of this study is to analyze the ischemic complications in patients with a ruptured AChA aneurysm. METHODS: We retrospectively reviewed 13 patients who were treated for ruptured AChA aneurysm from 1994 to 2007 at our hospital. The prognosis and complications were analyzed based on the institution's data, gender, age, the Hunt and Hess grade, the Glasgow coma scale, the Glasgow outcome scale, the symptoms and neurological examinations, the medical treatment, the digital subtraction angiography (DSA), the computed tomography (CT) and the magnetic resonance imaging (MRI). RESULTS: Forty-one (6%) out of 678 SAH patients had ischemic complications. Thirteen cases (2%) were caused by rupture of an anterior choroidal artery (AChA) aneurysm and 3 of these 13 cases (23.1%) had ischemic complications. Two of these 3 cases (15.4%) had neurological abnormality. Twelve out of the 13 AchA aneurysms had the saccular form. CONCLUSION: In cases of SAH from ruptured AchA aneurysm, the probability of ischemic complications was higher than that of general aneurysmal SAH. This seems to be due to the thin AChA and that the vascular territory of AChA is the area where ischemic brain damage can occur even by a mild vasospasm. So, when operating on a AChA aneurysm, maximum effort should be done to preserve the AChA. However, in the exceptional case with multiple AChAs, one AChA can be trapped without a definitive neurological deficit.

Anterior Choroidal Artery Syndrome occurring after endovascular coiling Treatment : Report of Two Cases / 대한뇌혈관외과학회지

Anterior choroidal artery (AChA) syndrome is widely known to be composed of a triad of hemiparesis, hemisensory loss and homonymous hemianopia. AChA syndrome is an unusual complication of aneurysmal treatment. This report documents two cases of AChA syndrome that occurred after an endovascular aneurysmal coiling procedure. Both cases showed complete recovery of the neurologic deficit at the time of discharge. To avoid this complication, meticulous caution is required to preserve the posterior communicating artery, the AChA and the various perforators during an endovascular procedure. When AChA syndrome occurs, immediate treatment is necessary, including vasodilators, thrombolytics and close observation of the patient's clinical status.

Analysis of Clip-induced Ischemic Complication of Anterior Choroidal Artery Aneurysms

OBJECTIVE: The surgical approach is typically similar to those used for other supraclinoid internal carotid artery (ICA) lesions. However, the surgical clipping of this aneurysm is complicated and as a result, can result in postoperative ischemic complications. We studied to clarify the clip-induced ischemic complication risk of AChA aneurysm and to get the benefits for helping decision making. METHODS: We retrospectively investigated 53 cases (4.0%) of AchA aneurysm treated surgically. We divided the AChA aneurysm to 3 subtype according to the origin of aneurysmal neck; A type originating from the AChA itself, J type from junction of AChA and ICA, and I type from the ICA itself. We evaluated brain CT about 1 week post-operative day to confirm the low density in AChA territory. RESULTS: Ruptured aneurysm was 26 cases and unruptured aneurysm 27 cases. The aneurysmal subtype of A, J, and I was 13, 17, and 23 cases. Of the 53 cases who performed surgical neck clipping, twelve (22.6%) had postoperative AChA distribution infarcts. Increased infarct after neck clipping had statistic significance in non-I subtype (p=0.005). CONCLUSION: It is easy to classify as "easy" surgery. But surgery for AChA aneurysms carries with it a significant risk of postoperative stroke. Don't always stick to clipping only, especially in non-I type of incidental small aneurysm, which has high risk of post-clip ischemic complications.

Extravasation from the Distal Anterior Choroidal Artery Aneurysm in Moyamoya Patient during Computed Tomographic Angiography

Three-dimensional computed tomographic angiography (CTA), a representative noninvasive radiologic technique, is being widely used for detecting vascular lesions in specific intracranial bleeding under a certain circumstance (acute nontraumatic subarachnoid hemorrhage). We encountered a case of extravasation of the contrast medium on CTA images that appeared as ribbon-like high-attenuation lesion from an aneurysm at the distal anterior choroidal artery in a young adult moyamoya patient. As CTA is used more frequently, it is imperative to understand such unusual but, potentially lethal image findings to conduct a prompt intervention.

Oculomotor Nerve Palsy due to Ruptured Multiple Anterior Choroidal Artery Aneurysms

We present a case of acute subarachnoid hemorrhage in a 64-year-old male with sudden onset of left ophthalmoplegia. Cerebral angiography demonstrated a 10mm elongated aneurysmal sac which arose from the left internal carotid-anterior choroidal artery junction. The pterional approach was performed as an early surgery for aneurysm clipping. At operative field, the anterior choroidal artery aneurysm which directed posteromedially and compressed the origin of left oculomotor nerve was confirmed. And the blood blister like-aneurysm was also seen at the superolateral portion of the proximal bifurcation of the internal carotid-anterior choroidal artery. A large anterior choroidal artery aneurysm was clipped and the blood blister like-aneurysm was reinforced. No case report has been previously published describing a ruptured anterior choroidal artery aneurysm accomplished with third cranial nerve palsy. We reported a case of multiple aneurysms of anterior choroidal artery that caused ipsilateral oculomotor nerve palsy.

Oculomotor Nerve Palsy due to Ruptured Multiple Anterior Choroidal Artery Aneurysms

We present a case of acute subarachnoid hemorrhage in a 64-year-old male with sudden onset of left ophthalmoplegia. Cerebral angiography demonstrated a 10mm elongated aneurysmal sac which arose from the left internal carotid-anterior choroidal artery junction. The pterional approach was performed as an early surgery for aneurysm clipping. At operative field, the anterior choroidal artery aneurysm which directed posteromedially and compressed the origin of left oculomotor nerve was confirmed. And the blood blister like-aneurysm was also seen at the superolateral portion of the proximal bifurcation of the internal carotid-anterior choroidal artery. A large anterior choroidal artery aneurysm was clipped and the blood blister like-aneurysm was reinforced. No case report has been previously published describing a ruptured anterior choroidal artery aneurysm accomplished with third cranial nerve palsy. We reported a case of multiple aneurysms of anterior choroidal artery that caused ipsilateral oculomotor nerve palsy.

Two cases of anterior choroidal artery territory infarction

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.