Contralateral Posterior Inferior Cerebellar Artery Research Articles

Occipital artery-to-PICA bypass: how I do it.

Posterior inferior cerebellar artery (PICA) aneurysms are uncommon, and their management is challenging because of the complex angioarchitecture of the PICA and the frequently nonsaccular aneurysm presentation. Endovascular therapy may not be feasible. We describe our technique of clip trapping with occipital artery (OA)-to-PICA bypass to treat a PICA aneurysm. Because the aneurysm affected the ipsilateral, dominant PICA, an OA-PICA bypass was chosen to ensure adequate flow and reduce risk to the contralateral PICA supply. The OA-PICA anastomosis is a safe and effective method to successfully achieve flow preservation with bypass reconstruction and aneurysm trapping.

Posterior Inferior Cerebellar Artery Pseudoaneurysm Clip Ligation With Reimplantation Into the Vertebral Artery: 3-Dimensional Operative Video.

We present the case of a 53-yr-old previously healthy male who presented with diffuse subarachnoid hemorrhage with intraventricular blood and hydrocephalus after an episode of slurred speech, left-sided facial droop, and left sided weakness. Cerebral angiography demonstrated a fusiform dissecting aneurysm at the origin of the left posterior inferior cerebellar artery (PICA). There appeared to be no good endovascular option that would preserve PICA. Due to the small size of the contralateral PICA, a PICA to PICA bypass was decided against. We elected to perform a PICA reimplantation to the vertebral artery and clip ligation of the pseudoaneurysm. ICG video angiogram and postoperative angiogram showed patency of the reimplanted PICA and complete obliteration of the pseudoaneurysm. All appropriate patient consents were obtained for this submission.Watch now at https://academic.oup.com/ons/article-lookup/doi/10.1093/ons/opy017 {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Posterior Inferior Cerebellar Artery Pseudoaneurysm Clip Ligation With Reimplantation Into the Vertebral Artery: 3-Dimensional Operative Video","caption":"","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_n27eens0"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} Disclosure The authors have no personal, financial, or institutional interest in any of the drugs, materials, or devices described in this article.

Hemibody pain relieved by microvascular decompression of the contralateral caudal medulla: Case report

Microvascular decompression (MVD) of cranial nerves has become an established treatment for trigeminal and (vago)glossopharyngeal neuralgia and for hemifacial spasm. The authors present the case of a 64-year-old man who had a 3.5-year history of severe, drug-resistant hemibody pain with sensory and autonomic disturbance. The ipsilateral trigeminal, cochlear, and glossopharyngeal function also was affected. The contralateral posterior inferior cerebellar artery was seen on magnetic resonance imaging to be indenting the caudal medulla anterolaterally, causing displacement. After MVD of the medulla, there was an immediate and complete resolution of the pain and almost complete resolution of the sensory and autonomic disturbances. The pain later recurred mildly and transiently. The residual symptoms had resolved by 2years.

発達した後下小脳動脈に発生した解離性動脈瘤

We report a rare case of dissecting aneurysm of the posterior inferior cerebellar artery (PICA) with vascular variation. A 38-year-old man, who had no medical, familial or traumatic histories, presented with headache, nausea and mild consciousness disturbance. Computed tomography (CT) imaging demonstrated subarachnoid hemorrhage with intra-ventricular hemorrhage. Angiography disclosed an aneurysm of left PICA, which did not involve the vertebral artery. The PICA was well developed and widely perfused the cerebellum and lower brain stem, which was accompanied by lack of ipsi-lateral anterior inferior cerebellar artery (AICA) and contra-lateral PICA. The aneurysm was successfully treated by trapping and revascularization procedure with occipital artery (OA)-PICA anastomosis. We suggest that congenital vascular variation related to well-developed PICA might lead to dissecting aneurysm, and that direct surgical treatment with bypass would be indicated for such patients to preserve hemodynamic integrity.

In vivo visualization of the PICA perfusion territory with super-selective pseudo-continuous arterial spin labeling MRI

In this work a method is described to discern the perfusion territories in the cerebellum that are exclusively supplied by either or both vertebral arteries. In normal vascular anatomy the posterior inferior cerebellar artery (PICA) is supplied exclusively by its ipsilateral vertebral artery. The perfusion territories of the vertebral arteries were determined in 14 healthy subjects by means of a super-selective pseudo-continuous ASL sequence on a 3T MRI scanner. Data is presented to show the feasibility of determining the PICA perfusion territory. In 10 subjects it was possible to accurately determine both PICA perfusion territories. In two subjects it was possible to determine the perfusion territory of one PICA. Examples in which it was not possible to accurately determine the PICA territory are also given. Additionally, the high variability of the extent of the PICA territory is illustrated using a statistical map. The posterior surface of the cerebellum is entirely supplied by the PICA in six subjects. The most posterior part of the superior surface is supplied by the PICA in eight subjects, and the inferior half of the anterior surface in six subjects. The inferior part of the vermis is supplied by the PICA in all subjects. Two subjects were found with interhemispheric blood flow to both tonsils from one PICA without contribution from the contralateral PICA. With the method as presented, clinicians may in the future accurately classify cerebellar infarcts according to affected perfusion territories, which might be helpful in the decision whether a stenosis should be considered symptomatic.

Forensic consequences of anatomical variants in cerebral vascularization - the case of bihemispheric posterior inferior cerebellar artery

The anatomy of the posterior inferior cerebellar artery (PICA) has a wider variability compared to the superior cerebellar artery (SCA) or the anterior inferior cerebellar artery (AICA). The PICA with bihemispheric distribution (bPICA) can be found in less than 0.1% of cases. We report here a rare such case, documented by anatomical microdissection. A true right bPICA was found emerging the origin of the basilar artery. From its lateral medullary segment the equivalent of the rostral trunk of an AICA was leaving, and from the tonsillomedullary segment of the bPICA emerged a trunk distributed in the territory of the caudal branch of the AICA. The telovelotonsilar segment of that bPICA was further sending off the PICAs proper, ipsilateral and contralateral. Each of these was supplying equally the vermis and the cerebellar hemisphere. The contralateral PICA proper was also distributed in the territory of the caudal trunk of the AICA, while the rostral trunk of the absent AICA was supplied by the SCA. Radiologists and surgeons should be aware of this variant, to diagnose it accurately, avoid pitfalls in diagnosis of bilateral cerebellar infarcts, and to avoid its damage during the microsurgical exposures. Key W ords: cerebellum, cerebellar artery, cerebellar infarct, arterial anatomic variant, PICA.

Simultaneous Vertebral Artery Dissection and Contralateral Posterior Inferior Cerebellar Artery Dissecting Aneurysm

The optimal treatment and appropriate follow-up period for an unruptured vertebral artery (VA) and/or posterior inferior cerebellar artery (PICA) dissection have not been established. Decisions regarding treatment of these vascular lesions are usually based on the manifesting symptoms and changes in radiologic findings during the follow-up period. We experienced a patient who had a simultaneous unruptured VA dissection and a contralateral PICA dissecting aneurysm. We did not find such a case in other literature.

Clinical presentation and treatment of distal posterior inferior cerebellar artery aneurysms

Aneurysms located at the distal portion of the posterior inferior cerebellar artery (PICA) are rare, and their clinical features are not fully understood. We report the clinical features and management of 30 distal PICA aneurysms in 28 patients treated during the past decade at Kagoshima University Hospital and affiliated hospitals. Our series includes 20 women and eight men. Of their 30 aneurysms, 24 were ruptured, and six were unruptured; there were 27 saccular and two fusiform aneurysms; one was dissecting. Their location was at the anterior-medullary (n = 4), lateral-medullary (n = 9), tonsillomedullary (n = 7), telovelotonsillar (n = 6), and cortical (n = 4) segment of the PICA. In 18 patients, angiographic features suggested hemodynamic stress including an absent contralateral PICA or ipsilateral anterior inferior cerebellar artery, termination of the vertebral artery (VA) at the PICA, and hyperplasia or occlusion of the contralateral VA. As three patients died before surgery, 27 aneurysms in 25 patients were surgically treated. Of these, 6 were unruptured aneurysms; 20 were clipped via midline or lateral suboccipital craniotomy, and 5 were embolized with Guglielmi coils; in one, the PICA flow was reconstructed by OA-PICA anastomosis, and in the other one, the PICA was resected. Of the 25 surgically treated patients, 22 (88%) had good outcomes. The predominant contributor to the development of distal PICA aneurysms is thought to be increased hemodynamic stress attributable to anomalies in the PICA and related posterior circulation. Both direct clipping and coil embolization yielded favorable outcomes in our series. However, considering the difficulties that may be encountered at direct clipping in the acute stage and the availability of advanced techniques and instrumentation, aneurysmal coiling is now the first option to address these aneurysms.

The bihemispheric posterior inferior cerebellar artery

Rarely, a solitary posterior inferior cerebellar artery (PICA) will supply both cerebellar hemispheres. We report four cases of this variant. We present a retrospective review of clinical information and imaging of patients undergoing angiography at our institution to identify patients with a bihemispheric PICA. There were four patients: three males and one female. One patient presented with a ruptured arteriovenous malformation, and one with a ruptured aneurysm. Two patients had normal angiograms. The bihemispheric PICA was an incidental finding in all cases. The bihemispheric vessel arose from the dominant left vertebral artery, and the contralateral posterior inferior cerebellar artery was absent or hypoplastic. In all cases, contralateral cerebellar supply arose from a continuation of the ipsilateral PICA distal to the choroidal point and which crossed the midline dorsal to the vermis. We conclude that the PICA may supply both cerebellar hemispheres. This rare anatomic variant should be considered when evaluating patients with posterior fossa neurovascular disease.

Ruptured aneurysm at the choroidal branch of the posterior inferior cerebellar artery: a case report and review of the literature

Background The authors present a rare case of a ruptured aneurysm at the choroidal branch of the posterior inferior cerebellar artery (PICA). Case description A 77-year-old female was admitted to our institute because of sudden onset of severe headache and vomiting. Radiologic examination revealed intraventricular hemorrhage caused by rupture of the aneurysm at the choroidal branch of the PICA. The fusiform aneurysm was resected after ligation via a midline suboccipital approach. Conclusion The conclusions drawn from this experience and a review of the literature include the following: (1) the aneurysm at the branch of the PICA is frequently associated with anomalies of the vascular structure, particularly in hypoplasty of the contralateral PICA; (2) hemodynamic stress is speculated to be a causative factor of these lesions; (3) cases with hypoplasty of the contralateral PICA have the possibility of developing nonmycotic peripheral aneurysms at the branch of the PICA; (4) these aneurysms should be managed immediately because of the high risk of rebleeding.

Extracranial Aneurysms of the Posterior Inferior Cerebellar Artery

Objective: Extracranial aneurysms of the distal posterior inferior cerebellar artery (PICA) are extremely rare and sometimes difficult to diagnose without an adequate angiogram. We present the first series of 3 patients who were evaluated by the senior author and treated surgically. Methods and Results: All 3 patients presented with subarachnoid hemorrhage (SAH). Clincial symptoms, included occipital headache, nuchal rigidity, abducens nerve palsy and rapid neurologic deterioration. A unilateral injection of the vertebral artery failed to show the distal contralateral PICA and the aneurysm in 1 patient. All patients underwent aneurysm clipping through a posterior fossa craniectomy and C-1 laminectomy. The aneurysms were located on the tonsillomedullary segment of the PICA, 10–12 mm below the level of the foramen magnum. Conclusions: It is important to adequately visualize the distal extent of both PICAs or these aneurysms may not be seen. Patients who present with SAH must have the entirety of both vertebral arteries evaluated to avoid missing these aneurysms. The aneurysms were located adjacent to the atlas necessitating an upper cervical laminectomy for adequate surgical exposure. In general, the patients did well postoperatively and none of the patients developed cerebral vasospasm.

A ???PICA communicating artery??? aneurysm

We present an unusual case of an aneurysm of the distal posterior inferior cerebellar artery (PICA). The aneurysm was associated with a unilateral PICA that supplied both cerebellar hemispheres and arose from an anastomotic vessel to the contralateral circulation, a branch of the contralateral PICA. Such an aneurysm has not been reported previously. The associated of vascular anomalies with aneurysms of the PICA is discussed.

A “PICA Communicating Artery” Aneurysm: Case Report

Abstract We present an unusual case of an aneurysm of the distal posterior inferior cerebellar artery (PICA). The aneurysm was associated with a unilateral PICA that supplied both cerebellar hemispheres and arose from an anastomotic vessel to the contralateral circulation, a branch of the contralateral PICA. Such an aneurysm has not been reported previously. The association of vascular anomalies with aneurysms of the PICA is discussed.