Origin Of Posterior Inferior Cerebellar Artery Research Articles

Endovascular treatment of ruptured pica aneurysms and association with its extradural origin: A single-center experience.

Background:Posterior inferior cerebellar artery (PICA) like other intracranial arteries is prone to aneurysm formation. Aneurysms usually arise from the vertebral artery (VA)—PICA junction and the proximal segment of the PICA. The surgical clipping of PICA aneurysms can be challenging and carries a potentially significant risk of morbidity and mortality. Experience with endovascular therapy has been limited to a few studies; however, the use of endovascular therapy as an alternative treatment to surgery has been increasing. We present our experience of last 5 years in treating the ruptured PICA aneurysms.Materials and Methods:A total of 11 patients with PICA aneurysms, out of them 7 were at proximal PICA, 2 at the vertebral-PICA junction, and 1 each at mid and distal PICA, underwent endovascular treatment at our institution between 2011 and 2016.Results:All the patients presented with an acute intracranial hemorrhage, confirmed on CT head. Most of the aneurysms were at proximal PICA (anterior and lateral medullary segments) with the partial incorporation of PICA origin in the sac. Low origin of PICA was seen in 7 (out of 11) cases, out of these cases, 5 had proximal PICA, aneurysm, and one (n = 1) had VA-PICA, junction aneurysm (1/7) and. one distal PICA aneurysm. There were seven proximal PICA aneurysms, and out of them, parent vessel occlusion was done in six and selective coiling in one (n = 1) case. From seven (n = 7) proximal PICA aneurysms, there were five cases of low origin and rests showed normal course and origin. Two (n = 2) junctional aneurysms were treated with simple coiling. Low origin was seen in right VA-PICA junction aneurysm. Endovascular treatment of all the 11 aneurysms was successful. The treatment consisted of selective aneurysm coiling in four (36.3%) patients and aneurysm with parent vessel trapping in seven patients (63.6%). Out of these seven patients, in one (n = 1) patient where aneurysm was distal PICA, glue embolization was done. There was no intra-procedural rupture/contrast extravasation or any thrombo-embolic complications. Follow-up studies ranged from 6 months to 5 years.Conclusion:Endovascular therapy of ruptured proximal PICA aneurysms is possible and safe with the use of adjuvant devices and should be considered as first-line treatment.

Endovascular recanalization for chronic symptomatic intracranial vertebral artery total occlusion: Experience of a single center and review of literature

ObjectiveThe optimal treatment of chronic symptomatic total occlusion of the intracranial vertebral artery (ICVA) remains undefined. We report a single-center experience of endovascular recanalization for patients with chronic symptomatic ICVA occlusion who were refractory to medical therapy. MethodsFrom Jan 2009 to Jan 2017, we retrospectively reviewed 14 consecutive patients presenting with recurrent symptoms attributed to the chronic ICVA occlusion. We searched previous literature using PubMed databases during the same period as comparison. ResultsEleven patients out of 14 presented initial symptoms to intervention less than 90days. The occlusion course was extrapolated on simultaneous two-vessel injection angiography or high-resolution MR imaging (HRMRI) in 13 cases. Nine patients had the occlusion beyond the origin of posterior inferior cerebellar artery (PICA) and 5 had the occlusion proximal to the PICA origin. The technical success rate of recanalization was 85.7% (12/14). Two patients (14.3%, 2/14) had peri-procedural complications: 1 developed TIA and 1 presented with perforator occlusion syndrome. Using the keyword-based search, we identified 6 studies at the same period. A total of 34 patients underwent recanalization with the successful recanalization rate at 94.1%, peri-procedural complication rate at 17.6% and mortality at 2.9%, respectively. ConclusionOur single-center study illustrated the feasibility and safety of ICVA recanalization. Great care should be taken as revascularization is of high risk. When patient selection, occlusion course and stage as well as neuroimaging evaluation are considered, endovascular recanalization may be a useful therapeutic modality.

Sequential Extradural Release of the V3 Vertebral Artery to Facilitate Intradural V4 Vertebral Artery Reanastomosis: Feasibility of a Novel Revascularization Technique.

Revascularization of the intradural vertebral artery (VA) usually involves V3-V4 bypass using an interposition graft. The interposition of a graft increases surgical time, adds risks, and requires 2 suture lines. To assess the feasibility of an excision-reanastomosis of V4 by sequentially releasing V3. Twenty specimens were prepared for surgical simulation of a far-lateral approach. The third and fourth segments of the VA were exposed through the far-lateral approach bilaterally. The V3 segment was divided into three subsegments: (1) V3 f : from entry to C1 transverse foramen to the point of exit from C1 transverse foramen; (2) V3 s : from V3 f to the distal point of V3 within the sulcus arteriosus; and (3) V3 d : from point V3 leaves the sulcus arteriosus to its dural entrance. After transecting the VA 2 mm proximal to the posterior inferior cerebellar artery origin, each subsegment was released sequentially. We measured the lengths obtained before and after releasing each segment by pulling the VA along its main axis to recreate a V3-V4 excision-reanastomosis. The V3 could not be effectively mobilized without release. When totally released, an average length of 13.15 mm was available for completing V3-V4 reanastomosis. Complete release of V3 from all its adhesions in its extracranial course can provide an average length of 13.15 mm for excision-reanastomosis. The present study shows the anatomic feasibility of the use of V3 segment in primary anastomosis after excision of a diseased segment of the intradural VA, laying the basis for future clinical application.

The Strategy of Endovascular Treatment for Ruptured Vertebral Artery Dissecting Aneurysm, Based on Its Location Relating to the Position of the Posterior Inferior Cerebellar Artery Origin

The Strategy of Endovascular Treatment for Ruptured Vertebral Artery Dissecting Aneurysm, Based on Its Location Relating to the Position of the Posterior Inferior Cerebellar Artery Origin

Endovascular treatment for ruptured and unruptured vertebral artery dissecting aneurysms: a meta-analysis

BackgroundDifferent endovascular modalities have been applied to the treatment of vertebral artery dissecting aneurysms, the most commonly used being internal trapping and stent-assisted coiling, although the ideal treatment remains controversial.ObjectiveTo...

Posterior inferior cerebellar artery reimplantation: buffer lengths, perforator anatomy, and technical limitations.

OBJECTIVE Reimplantation of the posterior inferior cerebellar artery (PICA) to the vertebral artery (VA) is a safe and effective bypass option after deliberate PICA sacrifice during the treatment of nonsaccular and dissecting aneurysms at this location. However, the anatomy and limitations of this technique have not been studied. The goal of this study was to define the surgical anatomy and buffer lengths specific to the proximal segment of the PICA related to 2 variations of PICA reimplantation: 1) reimplantation "along-VA" (simulating a dissecting VA aneurysm), and 2) reimplantation "across-VA" (simulating a nonclippable, proximal PICA aneurysm). METHODS Ten cadaver heads (20 sides) were prepared for surgical simulation. Twenty far-lateral approaches were performed. The PICA was mobilized and reimplanted onto the VA according to 2 different paradigms: 1) transposition along the axis of the VA (along-VA) to simulate a dissecting VA, and 2) transposition perpendicular to the axis of the VA (across-VA) to simulate a nonclippable, proximal PICA aneurysm. The buffer lengths provided by mobilization of the artery in each paradigm were measured and the anatomy of perforator branching on the proximal PICAs was analyzed. RESULTS The PICA was reimplanted in all surgical simulations. The most common perforating artery on the P1 and P2 segments was the short circumflex type. No direct perforator was found on the P1 segment. The mean buffer length with reimplantation along the VA axis was 13.43 ± 4.61 mm, and it was 6.97 ± 4.04 mm with reimplantation across the VA. The PICA was less maneuverable when it was reimplanted across the VA, due to perforator branches of the PICA (P3 segment). CONCLUSIONS The buffer lengths measured in this study describe the limitations of PICA reimplantation as a revascularization procedure for nonsaccular aneurysms in this location. PICA reimplantation is a revascularization option for dissecting VA aneurysms incorporating the PICA origin that are < 13 mm in length, and for nonsaccular proximal PICA aneurysms that are < 6 mm in diameter. The final decision to reimplant the PICA depends on careful inspection of perforator anatomy that is not visible preoperatively on angiography, as well as an assessment of technical difficulty intraoperatively.

Intracranial-to-intracranial bypass for posterior inferior cerebellar artery aneurysms: options, technical challenges, and results in 35 patients.

OBJECT Intracranial-to-intracranial (IC-IC) bypasses are alternatives to traditional extracranial-to-intracranial (EC-IC) bypasses to reanastomose parent arteries, reimplant efferent branches, revascularize branches with in situ donor arteries, and reconstruct bifurcations with interposition grafts that are entirely intracranial. These bypasses represent an evolution in bypass surgery from using scalp arteries and remote donor sites toward a more local and reconstructive approach. IC-IC bypass can be utilized preferentially when revascularization is needed in the management of complex aneurysms. Experiences using IC-IC bypass, as applied to posterior inferior cerebellar artery (PICA) aneurysms in 35 patients, were reviewed. METHODS Patients with PICA aneurysms and vertebral artery (VA) aneurysms involving the PICA's origin were identified from a prospectively maintained database of the Vascular Neurosurgery Service, and patients who underwent bypass procedures for PICA revascularization were included. RESULTS During a 17-year period in which 129 PICA aneurysms in 125 patients were treated microsurgically, 35 IC-IC bypasses were performed as part of PICA aneurysm management, including in situ p3-p3 PICA-PICA bypass in 11 patients (31%), PICA reimplantation in 9 patients (26%), reanastomosis in 14 patients (40%), and 1 V3 VA-to-PICA bypass with an interposition graft (3%). All aneurysms were completely or nearly completely obliterated, 94% of bypasses were patent, 77% of patients were improved or unchanged after treatment, and good outcomes (modified Rankin Scale ≤ 2) were observed in 76% of patients. Two patients died expectantly. Ischemic complications were limited to 2 patients in whom the bypasses occluded, and permanent lower cranial nerve morbidity was limited to 3 patients and did not compromise independent function in any of the patients. CONCLUSIONS PICA aneurysms receive the application of IC-IC bypass better than any other aneurysm, with nearly one-quarter of all PICA aneurysms treated microsurgically at our center requiring bypass without a single EC-IC bypass. The selection of PICA bypass is almost algorithmic: trapped aneurysms at the PICA origin or p1 segment are revascularized with a PICA-PICA bypass, with PICA reimplantation as an alternative; trapped p2 segment aneurysms are reanastomosed, bypassed in situ, or reimplanted; distal p3 segment aneurysms are reanastomosed or revascularized with a PICA-PICA bypass; and aneurysms of the p4 segment that are too distal for PICA-PICA bypass are reanastomosed. Interposition grafts are reserved for when these 3 primary options are unsuitable. A constructive approach that preserves the PICA with direct clipping or replaces flow with a bypass when sacrificed should remain an alternative to deconstructive PICA occlusion and endovascular coiling when complete aneurysm occlusion is unlikely.

Treatment of dissecting aneurysms of the PICA: Anatomical considerations and clinical outcome

Posterior inferior cerebellar artery (PICA) dissecting aneurysms require rapid and aggressive treatment by sacrificing the parent vessel of the aneurysm-bearing dissected vessel. We assessed the clinical consequences of PICA occlusion in view of the local vascular anatomy. We performed a retrospective search of our neurovascular database in the period 2007-2012. Patient characteristics, including clinical presentation, WFNS (World Federation of Neurosurgical Societies) grading and Glasgow Outcome Scale (GOS), were recorded. CT and CT angiographic findings as well as the detailed vascular anatomy including collateral circulation were assessed. We identified 10 patients (5 male; mean age 50 years). Eight patients presented with WFNS grade I and II, one with grade IV and one with grade V. All patients were treated with parent vessel occlusion (PVO). An extradural PICA origin was seen in three patients. Collateral circulation was visible before PVO in two and after PVO in seven additional patients. Despite the presence of collaterals, mild cerebellar ischemia occurred in three patients, without development of a Wallenberg syndrome. Outcome was favorable in 9 patients (8 patients GOS 5, one patient GOS 4). One patient died due to the mass effect of the initial cerebellar hematoma. PVO to treat PICA dissecting aneurysms was well tolerated with a 90% favorable outcome. Regional collateral circulation and vascular variations permitted relative safe vessel occlusion with only minor cerebellar symptoms in this small group of patients.

Safety of Unilateral Endovascular Occlusion of the Cervical Segment of the Vertebral Artery without Antecedent Balloon Test Occlusion

Antecedent balloon test occlusion is often performed prior to vertebral artery sacrifice, but there is limited data to suggest this adds a significant clinical benefit, especially in the setting of trauma. Furthermore, balloon test occlusion can be time-consuming, add to the technical complexity of the procedure, and increase the overall cost of treatment. The purpose of this study was to determine the safety of unilateral vertebral artery occlusion without antecedent balloon test occlusion as part of the treatment regimen in patients with traumatic vertebral artery dissection, cervical tumor, or intracranial aneurysm. The medical records and imaging studies of 59 patients in whom unilateral endovascular cervical vertebral artery occlusion was performed were retrospectively reviewed. Procedure-related stroke was defined as imaging evidence of acute infarct in the vascular territories supplied by the occluded vertebral artery or new focal neurologic deficit developing in the first 30 days after vertebral artery occlusion attributable to infarction in the posterior circulation. Fifty-nine patients underwent unilateral endovascular cervical vertebral artery occlusion to prevent potential thromboembolic complications of vertebral artery injury, for treatment of intracranial aneurysms, or for presurgical embolization of a cervical vertebral tumor. Unilateral occlusion was performed when endovascular reconstruction was considered impossible or deemed more risky than deconstruction. Fifty-eight of the 59 patients underwent vertebral artery occlusion without antecedent balloon test occlusion. None of the 59 patients had clinical or imaging evidence of a postprocedural infarct. In this series, endovascular occlusion of a cervical segment of 1 vertebral artery was safely performed without antecedent balloon test occlusion. As long as both vertebral arteries were patent and converged at the vertebrobasilar junction, there was anatomic potential for retrograde filling of the distal intracranial vertebral artery to the level of the posterior inferior cerebellar artery origin, and there was no major vascular supply to the spinal cord arising from the target segment of the affected vessel. Dominant and nondominant vertebral arteries were safely occluded, and no infarcts were attributed to the treatment.

Endovascular treatment of ruptured proximal PICA aneurysms: a single-center 5-years experience.

Posterior inferior cerebellar artery (PICA) like other intracranial arteries is prone to aneurysm formation. Aneurysms usually arise from the vertebral artery (VA) - PICA junction and the proximal segment of the PICA. The use of endovascular treatment as an alternative treatment to surgery has been increasing. We present our last 5 years' experience in treating the ruptured proximal PICA aneurysms. Retrospective analysis of records of all patients with ruptured VA-PICA junction aneurysms treated at our referral center between July 2008 and July 2013 was performed. Over the last 5 years, we came across 17 patients who had aneurysms of proximal PICA or VA-PICA junction out of which 13 patients underwent endovascular treatment for ruptured saccular VA-PICA junction aneurysms and were the focus of this research. Follow-up studies ranged from 6 months to 3 years. All the patients presented with an acute intracranial hemorrhage on NCCT. All the aneurysms were at VA-PICA junction with partial or complete incorporation of PICA origin in the sac. Endovascular treatment of all the 13 aneurysm was successful in the first attempt. Aneurysms were treated with balloon assisted coiling either by placing the balloon across the VA-PICA junction (n = 3) or in the vertebral artery proper (n = 9). Stent assisted coiling VA-PICA was performed in one aneurysm (n = 1). There was no intra-procedural rupture of the aneurysms. Endovascular therapy of ruptured proximal PICA aneurysms is possible and safe with the use of adjuvant devices and should be considered as first line treatment.

Stent Placement to Treat Ruptured Vertebral Dissecting Aneurysms

Conventional endovascular treatment may have limitations for vertebral dissecting aneurysm involving the origin of the posterior inferior cerebellar artery (PICA). We report our experiences of treating vertebral dissecting aneurysm with PICA origin involvement by placing a stent from the distal vertebral artery (VA) to the PICA to save the patency of the PICA. Stenting from the distal VA to the PICA was attempted to treat ruptured VA dissecting aneurysm involving the PICA origin with sufficient contralateral VA in eight patients. The procedure was successfully performed in seven patients with one failure because of PICA origin stenosis, which was treated with two overlapping stents. In the seven patients, PICAs had good patency on postoperative angiography and transient lateral brainstem ischemia represents a procedure-related complication. Follow-up angiographies were performed in seven patients and showed recanalization of the distal VA in three patients without evidence of aneurysmal filling. There was no evidence of aneurysm rupture during the follow-up period, and eight patients had favorable outcomes (mRS, 0 - 1). Placing a stent from the distal VA to the PICA with VA occlusion may present an alternative to conventional endovascular treatment for vertebral dissecting aneurysm with PICA origin involvement with sufficient contralateral VA.

Anomalous posterior inferior cerebellar artery crossing the C1-2 facet in patient with atlanto-axial dislocation associated with down’s syndrome

Dear Editor, Vertebral artery variations at the level of C1-2 have been documented, especially in patients with Down’s syndrome [5]. Additionally, cranio-vertebral junction (CVJ) anomalies are often seen in patients with Down’s syndrome [2]. The origin of posterior inferior cerebellar artery (PICA) at the level of C1-2 is one of the variations, with a reported incidence of approximately 1.1 % in normal population [4]. Of interest, such a variation of PICA has not been reported in CVJ anomaly with Down’s syndrome. It is important to identify such variation preoperatively to avoid complication during surgery for CVJ. A 7-year-old girl with Down’s syndrome presented with spastic quadriparesis that progressed over 6 months. X ray CVJ showed os-odontoideum with atlanto-axial dislocation reducing on extension (Fig. 1). Computed tomography (CT) Angiogram (2D and 3D reconstructed) images revealed the right PICA originating at the C1-2 level and crossing the joint space (Fig. 1). The patient underwent a posterior fusion. Intraoperatively, the bilateral C2 ganglion was cut. The vertebral artery (VA) could be seen coursing above the C1 arch, whereas the PICA was seen originating from VA between C1 and C2 transverse foramina and then crossing the C1-2 joint on the right side to course beneath the C1 arch. The vessel was carefully dissected, taking care not to injure it. The facetal surfaces were drilled lateral after retracting the PICA gently away from it. The lateral mass screws were inserted in C1, retracting the vessel gently to avoid injury. C2 pars-interarticularis screws were inserted and fused to C1 lateral mass screws. Bone grafts placed between the C1-2 joint and decorticated surface helped achieve a strong bony fusion. Her myelopathy improved significantly after 3 months. The PICA may originate extra-durally and extra-cranially in about 5–20 % [1]. An extradural PICA may arise just outside the dura at the CVJ or laterally above the transverse foramen of the atlas or between the transverse foramina of C-2 and C-1 [1]. In the normal population, the incidence of PICA originating between C2 and C1 transverse foramina is 1.1 % [4]. However, the incidence of other origins of PICA could not be localized in literature. Additionally, both CVJ and Vertebral artery (VA) abnormalities are more often seen in patients with Down’s syndrome as compared to those without it [2, 5]. Of interest, a anomalous PICA with CVJ abnormality in Down’s syndrome has never been described in the past. The variations in VA and origin of PICA is thought to be the result of variations in the development of the lateral spinal artery (LSA) and posterior spinal artery (PSA). The anterior or posterior location of the PICA (C2 origin) at the foramen magnum origin and the absence or presence of separate LSA help to distinguish the LSA from the PSA variant [3]. It has been suggested that chromosomal abnormality in Down syndrome contributes to VA abnormalities at CVJ [5]. After originating from the VA beyond the C2 transverse foramina, the PICA crosses across the posterior aspect of C1-2 joint to enter the dura at the level of C1. Such an origin and course of PICA makes it susceptible to injury during surgery, for the CVJ especially, while the C1-2 facet is being dissected, distracted and fixed with lateral mass screws. The abnormal PICA may be injured directly or its handling may tear its origin from the VA. Occasionally, the VA may end as this abnormal PICA [4]. The neurological damage due to PICA injury depends on the area it supplies. Although extradural PICAs do not send perforating branches to the anterior surface of the medulla P. Salunke (*) : S. Futane Department of Neurosurgery, PGIMER, Sector 12, Chandigarh, India 1600l2 e-mail: drpravin_salunke@yahoo.co.uk

Stent-assisted coil embolization of wide-necked posterior inferior cerebellar artery aneurysms

Endovascular coil embolization of posterior circulation aneurysms has advantages over a surgical approach. However, the application of coil embolization is sometimes limited in wide-necked posterior inferior cerebellar artery (PICA) aneurysms, which are incorporating the origin of the branch. Presented here is a series of patients who were subjected to stent-supported coil embolization of PICA aneurysms. From a prospective data repository, we retrieved records of seven consecutive patients with PICA aneurysms, all of whom were treated by stent-assisted coil embolization between January 2010 and November 2012. Outcomes were analyzed in terms of aneurysm morphology and clinical status. In all seven instances, the stents were placed from proximal PICA to vertebral artery (VA). A retrograde approach, via contralateral VA, was performed in five patients, where the origin of PICA from VA assumed an acute angle. In the other two patients, where the angles were obtuse, the stenting was done antegrade, via ipsilateral VA. Out of five patients with retrograde approach, single puncture and a single guiding catheter sufficed in three patients, whereas the remaining two patients required dual puncture and two guiding catheters. Endovascular treatments, as performed, resulted in excellent outcomes for all seven patients, although an asymptomatic thrombus developed in one patient with a ruptured aneurysm. For coil embolization of PICA aneurysm requiring stent protection, either ipsilateral or contralateral VA access routes may be used, depending on the angle of PICA origin and the configuration of the aneurysm.

Technical Considerations in the Endovascular Management of Aneurysms of the Posterior Inferior Cerebellar Artery

Aneurysms of the posterior inferior cerebellar artery (PICA) are rare, comprising 0.5% to 3% of intracranial aneurysms. Because their anatomic location relative to the PICA origin is variable, several endovascular techniques are used in their management. To evaluate and discuss endovascular techniques for the treatment of PICA aneurysms. We analyzed our prospectively maintained database to identify PICA aneurysms treated over a 12-year period from 1999 to 2011. Twenty patients were assessed angiographically for endovascular treatment. Treatment was successfully performed in 17, but 3 were deemed unsuitable and were referred for surgery. Patients ranged in age from 15 to 82 years (mean, 60.5); 85% (17/20) were women. Thirteen (65%) presented with subarachnoid hemorrhage, and 3 (15%) had been previously treated surgically. Although the aneurysms were located at the PICA origin in 13 (65%), their involvement with the PICA and vertebral artery was variable. Some arose distinctly from the origin, and others incorporated the PICA itself. Five patients were treated for distal PICA aneurysms. Treatment techniques included direct coiling, vertebral artery balloon remodeling with coiling, PICA balloon remodeling with coiling, and parent vessel sacrifice of PICA with either coiling or glue embolization. Complete occlusion was initially achieved in 11 of 17 patients. Of the 6 remaining patients, 3 improved to complete occlusion at follow-up, 2 underwent re-treatment, and 1 remained stable. No patient experienced posttreatment hemorrhage. A variety of endovascular techniques are required for the management of PICA aneurysms. Specific techniques vary according to the location of the aneurysm in relation to the PICA origin, distal course of the artery, and the vertebral artery. BRAT, Barrow Ruptured Aneurysm TrialmRS, modified Rankin scorenBCA, n-butyl cyanoacrylatePICA, posterior inferior cerebellar arterySAH, subarachnoid hemorrhageVA, vertebral artery.

Endovascular Treatment of Ruptured Vertebral Artery Dissecting Aneurysms Involving the Posterior Inferior Cerebellar Artery

We read the article of Kim et al entitled “Stenting from the Vertebral Artery to the Posterior Inferior Cerebellar Artery” with special interest.[1][1] In their series, 2 patients had vertebral artery (VA) dissecting aneurysms involving the posterior inferior cerebellar artery (PICA) origin. The

Bilateral Vertebral Artery Dissecting Aneurysms Presenting with Subarachnoid Hemorrhage Treated by Staged Coil Trapping and Covered Stents Graft

The treatment of bilateral vertebral artery dissecting aneurysms (VADAs) presenting with subarachnoid hemorrhage (SAH) is still challenging. The authors report a rare case of bilateral VADA treated with coil trapping of ruptured VADA and covered stents implantation after multiple unsuccessful stent assisted coiling of the contralateral unruptured VADA. A 44-year-old woman was admitted to our hospital because of severe headache and sudden stuporous consciousness. Brain CT showed thick SAH and intraventricular hemorrhage. Cerebral angiography demonstrated bilateral VADA. Based on the SAH pattern and aneurysm configurations, the right VADA was considered ruptured. This was trapped with endovascular coils without difficulty. One month later, the contralateral unruptured VADA was protected using a stent-within-a-stent technique, but marked enlargement of the left VADA was detected by 8-months follow-up angiography. Subsequently two times coil packing for pseudosacs resulted in near complete occlusion of left VADA. However, it continued to grow. Covered stents graft below the posterior inferior cerebellar artery (PICA) origin and a coronary stent implantation across the origin of the PICA resulted in near complete obliteration of the VADA. Covered stent graft can be used as a last therapeutic option for the management of VADA, which requires absolute preservation of VA flow.

Bilateral Approach for Stent-assisted Coiling of Posterior Inferior Cerebellar Artery Aneurysms - Two Cases

Aneurysms of the posterior inferior cerebellar artery (PICA) are rarely encountered. In particular, due to frequent anatomic complexity and the presence of nearby critical structures, PICA origin aneurysms are difficult to treat. However, recent reports of anecdotal cases using advanced endovascular instruments and skills have made the results of endovascular treatment rather outstanding. PICA preservation is the key to a successful endovascular treatment, based on the premise that a PICA origin aneurysm is well occluded. To secure PICA flow, stenting into the PICA would be the best method, however, it is nearly impossible technically via the ipsilateral vertebral artery (VA) if the PICA arose at an acute angle from the sac. In such a case, a bilateral approach for stent-assisted coiling can be a creative method for achievement of two goals of both aneurysm occlusion and PICA preservation: ipsilateral approach for coil delivery and contralateral cross-over approach for stent delivery via a retrograde smooth path into the PICA.

Endovascular Treatment of Bilateral Intracranial Vertebral Artery Dissecting Aneurysms Presenting With Subarachnoid Hemorrhage

Optimal management of bilateral vertebral artery dissecting aneurysms (bi-VDAs) causing subarachnoid hemorrhage (SAH) remains unclear. To investigate the treatment methods and outcomes of bi-VDA causing SAH. Seven patients were treated endovascularly for bi-VDA causing SAH. Treatment methods and outcomes were evaluated retrospectively. Two patients were treated with 2 overlapping stents for both ruptured and unruptured VDAs, 2 with 2 overlapping stents and coiling for ruptured VDA and with conservative treatment for unruptured VDA, 1 with internal trapping (IT) for ruptured VDA and stent-assisted coiling for unruptured VDA, 1 with IT for ruptured VDA and 2 overlapping stents for unruptured VDA, and 1 with IT for ruptured VDA and a single stent for unruptured VDA. None had rebleeding during follow-up (range, 15-48 months). All patients had favorable outcomes (modified Rankin Scale score, 0-2). On follow-up angiography at 6 to 36 months, 9 treated and 2 untreated VDAs revealed stable or improved state, whereas 3 VDAs in 2 patients showed regrowth. Of the 3 recurring VDAs, 1 was initially treated with IT but recurred owing to retrograde flow to the ipsilateral posterior inferior cerebellar artery (PICA), the second was treated with single stent but enlarged, and the last was treated with 2 overlapping stents and coiling but recurred from the remnant sac harboring the PICA origin. All 3 recurred VDAs were retreated with coiling with or without stent insertion. Bilateral VDAs presenting with SAH were safely treated with endovascular methods. However, endovascular treatment may be limited for VDAs with PICA origin involvement.

Incidence and Risk Factors of Recurrence After Endovascular Treatment of Intracranial Vertebrobasilar Dissecting Aneurysms

The incidence and risk factors for recurrence after endovascular treatment of intracranial vertebrobasilar dissecting aneurysms (VBDAs) have not been studied. We aimed to evaluate the incidence and risk factors for recurrence after endovascular treatment of VBDAs. A total of 111 patients (mean age, 45±10 years) underwent endovascular treatment for 119 VBDAs (ruptured/unruptured=73:46). Incidence and risk factors for recurrence were retrospectively evaluated. Sixty-two VBDAs were treated by a reconstructive technique by using 1 to 3 overlapping stents with or without coiling, and 57 VBDAs were treated by a deconstructive technique by using proximal occlusion or internal trapping at the dissected segment of the parent artery. Follow-up angiography was available for 97 VBDAs (81.5%) in 89 patients at 3 days to 48 months (median, 13 months) after treatment. There were 13 recurrences: 6 had rebleeding but 7 had no rebleeding. All 6 hemorrhagic recurrences had initially presented with a ruptured form. Ten recurrences were confirmed by angiography, but 3 recurrences with rebleeding did not receive follow-up angiography. The rate of post-treatment recurrence did not differ between reconstructive and deconstructive treatments. Involvement of the posterior inferior cerebellar artery origin (odds ratio=8.026; 95% confidence interval, 1.561 to 41.259; P=0.013) was the only independent risk factor for recurrence. There was a 13% recurrence after endovascular treatment of VBDAs. Posterior inferior cerebellar artery origin involvement was the only independent risk factor for recurrence after endovascular treatment of VBDAs.

Dissection of the posterior inferior cerebellar artery in the hypereosinophilic syndrome

Dissection of the posterior inferior cerebellar artery in the hypereosinophilic syndrome