Superior Cerebellar Artery Aneurysm Research Articles

Osteogenesis Imperfecta, Multiple Intra-Abdominal Arterial Dissections and a Ruptured Dissecting-Type Intracranial Aneurysm

We describe an adult patient with a ruptured dissecting-type superior cerebellar artery aneurysm and known osteogenesis imperfecta. He was successfully treated with coil embolization and intentional parent vessel sacrifice. During his hospital admission, he also suffered from abdominal distension. An incidental note was made of multiple intra-abdominal arterial dissections. These were managed conservatively. We review the rare association of osteogenesis imperfecta and intracranial aneurysms, as well as discuss management implications.

Delayed Herniation of Coil Loop and Spontaneous Reposition in a Superior Cerebellar Artery Aneurysm

Herniation of coil loops into the parent artery is one of the complications of endovascular embolization with detachable coils. In this clinical setting, we cannot predict the consequence of the herniated coil loop. We report an unusual case of a superior cerebellar artery (SCA) aneurysm with delayed coil herniation into the basilar artery and spontaneous reposition into the SCA.

Dissecting peripheral superior cerebellar artery aneurysms: Report of two cases and review of the literature

Background:Only a limited number of dissecting aneurysms of the peripheral cerebellar arteries have been previously described, and very few of these cases involve the superior cerebellar artery (SCA). Due to the rarity of these lesions, there is little consensus regarding prognosis and management. We describe our experience with two cases of complex peripheral SCA dissecting aneurysms and review the existing literature on this fascinating entity.Case Description:Two patients, both with SCA dissecting aneurysms not amenable to endovascular treatment underwent microsurgical clipping, one with the associated removal of a tentorial meningioma. In each procedure a combined subtemporal, presigmoidal approach was performed. Surgical clips were utilized to reconstruct the aneurysms, and both patients were discharged without complication. Surgical management of complex distal SCA fusiform aneurysm is challenging and options include wrap/clip reconstruction, proximal occlusion, trapping, and distal outflow occlusion. When possible, preservation of the parent artery is preferred to mitigate the risk of brainstem infarction. If proximal occlusion or trapping are employed, we have advocated for the use of combined distal revascularization techniques to prevent permanent ischemic damage of the brainstem and cerebellar hemisphere.Conclusions:Peripherally dissecting aneurysm of the SCA is an uncommon entity. Management of these lesions is best handled by an experienced neuro-endovascular team combined with a neurovascular surgeon skilled in skull base approaches.

SPONTANEOUS DELAYED PROXIMAL MIGRATION OF ENTERPRISE STENT AFTER STAGED TREATMENT OF WIDE- NECKED BASILAR ANEURYSM

To document a unique technical issue with a relatively newly released intravascular stent used for adjunctive treatment of wide-necked cerebral aneurysms. A 48-year-old woman with a sister who had a large unruptured wide-necked basilar aneurysm underwent screening evaluation that revealed a nearly identical aneurysm. She also harbored small unruptured right superior cerebellar and left anterior cerebral artery aneurysms. Endovascular treatment of the 11.5-mm basilar aneurysm was performed in a staged manner. Stent placement was performed first, followed by delayed coil embolization of the aneurysm 9 weeks later. Follow-up angiography at the time of the second procedure revealed significant spontaneous proximal migration of the Enterprise Vascular Reconstruction Device and Delivery System (Cordis Neurovascular, Inc., Miami Lakes, FL) with the distal extent of the device migrating from the right P2 segment into the neck of the aneurysm. Coil embolization was performed despite migration of the vascular reconstruction device. The use of stents in the endovascular treatment of cerebral aneurysms has vastly improved our ability to treat complex lesions. Technical issues remain with these devices, and description of this event may alter the way we use the Enterprise Vascular Reconstruction Device and Delivery System in terms of staging procedures, and when evaluating the particular vascular anatomy of the individual patient with special attention to parent artery vessel size.

The extradural temporopolar approach: a review of indications and operative technique

The extradural temporopolar approach is used for enhanced exposure of the cavernous sinus and petroclival regions in the treatment of complex lesions not amenable to sole treatment via radiosurgical or endovascular methods. The authors' objective was to review the indications, surgical experience, and operative technique in a series of patients who underwent surgery with this approach. The authors conducted a retrospective review to identify patients who underwent a temporopolar approach from 1992 to 2008. An orbitozygomatic craniotomy was frequently used, followed by extradural retraction of the temporal lobe. A sequential progression of bone removal at the anterior and middle skull base, followed by opening the layers of the lateral wall of the cavernous sinus was next performed to safely retract the brain and widen the exposure to the cavernous sinus, interpeduncular fossa, and upper petroclival regions. Sixty-six patients were identified and included in the study. The mean patient age was 49 years. The main indications for surgery were as follows: meningioma (25 patients, 38%), basilar artery aneurysm (11 patients, 17%), trigeminal schwannoma (7 patients, 11%), chordoma (5 patients, 7%), hemangioma (3 patients, 5%), pituitary adenoma (3 patients, 5%), superior cerebellar artery aneurysm (3 patients, 5%), and other lesions (9 patients, 14%). Complications included hemiparesis in 4 patients (6%), infarcts in 4 patients (6%), transient aphasia in 1 patient (1.5%), and cranial nerve paresis in 20 patients (30%). The extradural temporopolar approach offers a relatively safe and wide exposure of the sphenocavernous and petroclival regions. Mobilization of the cranial nerves and internal carotid artery allow gentle brain retraction and maximal preservation of venous outflow. This is an advantageous approach to large tumors in these regions and for complex upper basilar artery or superior cerebellar artery aneurysms.

Tentorial Incision in a Lateral-medial Direction with Minimal Retraction of the Temporal Lobe in the Subtemporal Transtentorial Approach to the Middle Tentorial Incisural Space

The subtemporal transtentorial approach provides excellent exposure of the middle incisural space. A modification of the subtemporal transtentorial approach with use of a partial mastoidectomy is presented to avoid damage to the temporal lobe as a result of retraction as well as damage to venous structures. Four patients, one with a superior cerebellar artery aneurysm, one with a metastatic tumor in the midbrain, one with a tentorial meningioma, and one with a tentorial schwannoma were treated with the present approach. After subtemporal craniotomy, all of the cortical bone overlying the mastoid was removed. The mastoid air cells were drilled down, and the upper part of Trautman's triangle was exposed above the level of the lateral semicircular canal. The presigmoid dura and the temporal dura were opened and connected by incising the superior petrosal sinus. The cerebellar tentorium was incised in a lateral-medial direction along the angle of the tentorium. In each case, the tentorium was incised with minimal retraction of the temporal lobe without any damage to the temporal lobe, or venous structures. The present approach yielded excellent visualization of the lesion and adjacent neurovascular structures. In 3 of 4 cases, the lesions were successfully treated. In the patient with a tentorial schwannoma extending from the middle to posterior incisural space, the extreme lateral supracerebellar-infratentorial approach was combined with the present approach. Although additional partial mastoidectomy is time-consuming, it reduces the risk of damage to the temporal lobe as a result of retraction as well as damage to venous structures.

Posterior Clinoidectomy: Dural Tailoring Technique and Clinical Application

The posterior clinoid process, a bony prominence at the superolateral aspect of the dorsum sellae, has a strategic importance in a transcavernous approach to basilar tip aneurysms. To further optimize this microsurgical technique during posterior clinoidectomy, we performed a cadaveric study of this regional anatomy, describe a technique called dural tailoring, and report initial results in the surgical treatment of upper basilar artery (BA) aneurysm. After 10 adult cadaver heads (silicone-injected) were prepared for dissection, a posterior clinoidectomy with dural tailoring was performed. The dura overlying the upper clivus was coagulated with bipolar electrocoagulation and incised. Stripping dura off the clivus and lateral reflection then exposed the ipsilateral posterior clinoid process and dorsum sellae, thus creating a dural flap. Posterior clinoidectomy with dural tailoring was then used in seven patients with upper BA aneurysms. Our stepwise modification of the posterior clinoidectomy with dural tailoring created a flap that afforded protection of the cavernous sinus and oculomotor nerve. During surgery, there were no recorded intraoperative injuries to neurovascular structures. One patient died postoperatively from morbidity related to severe-grade subarachnoid hemorrhage. Postoperative oculomotor nerve palsy occurred in 3 patients (43%). In all cases, the nerve was anatomically preserved and partial to complete recovery was recorded during the first postoperative year. This technique effectively provided exposure of retrosellar upper basilar aneurysms in seven patients (basilar tip 43% and superior cerebellar artery aneurysms 57%). Outcomes and safety are at least equivalent to or better than basilar aneurysm surgery performed without surgical adjuncts, presumably a less complex subset.

DOUBLE-BALLOON TRAPPING TECHNIQUE FOR EMBOLIZATION OF A LARGE WIDE-NECKED SUPERIOR CEREBELLAR ARTERY ANEURYSM

To describe a novel double-balloon trapping technique for endovascular embolization of a broad-based saccular aneurysm of the superior cerebellar artery. A 62-year-old man with a history of diabetes, coronary artery disease, and smoking presented with a syncopal episode. Catheter angiography revealed a large (11.7 x 9.4 x 11.2 mm) right superior cerebellar artery (SCA) aneurysm with a 7-mm neck, incorporating the origin of the right SCA. An endovascular double-balloon trapping technique was used. Using bilateral groin access and bilateral vertebral artery guide catheters, a 4 x 20 mm HyperGlide balloon (ev3 Neurovascular, Irvine, CA) was placed across the neck of the aneurysm, and a 4 x 7 mm HyperForm balloon (ev3 Endovascular Inc., Plymouth, MN) was placed within the aneurysm. The aneurysm was catheterized with an Echelon 14 microcatheter (ev3 Endovascular Inc.). The inflated HyperGlide balloon was used to protect the parent basilar artery and "trap" the smaller HyperForm balloon within the aneurysm. The HyperForm balloon was inflated within the aneurysm and gently retracted to protect the origin of the SCA at the aneurysm neck. The aneurysm was coiled with the balloons inflated. A 4.5 x 20 mm Neuroform stent (Boston Scientific, Natick, MA) was deployed across the aneurysm neck. Final procedural angiography showed near complete occlusion of the aneurysm and preservation of flow in the SCA. Follow-up angiography at 8 months showed progressive thrombosis with complete occlusion of the aneurysm, preserved patency of the SCA, and anatomic reconstruction of the native artery. The patient remained neurologically normal at the time of the follow-up evaluation. Double-balloon trapping is a novel endovascular technique that can be used to treat wide-necked aneurysms and maintain patency of side branches incorporated into the aneurysm neck.

Morphological study of aneurysms at the junction of the superior cerebellar artery.

Superior cerebellar artery (SCA) aneurysms sometimes involve the origin of the SCA making treatment difficult. We focused on the morphological characteristics of SCA aneurysms and adjacent vascular structures to apply clinical decision-making for the treatment strategy. Sixty-nine SCA aneurysms, including 34 ruptured and 35 unruptured ones, had been treated for over 12 years. Multiple aneurysms were associated in 30 patients. The pattern of the neck position of aneurysms was classified into three types: Type A: no SCA-involved type; Type B: half involved type with SCA originating from the aneurysmal neck; Type C: pure SCA aneurysm with all the neck mounting on SCA. Morphological and clinical analysis was done between ruptured and unruptured aneurysms and among the three types. There was no difference in patient profile between ruptured and unruptured aneurysms. The angle formed by the posterior cerebral artery and SCA on the aneurysm side was obtuse in 62 (90%) patients. From the morphological point of view the SCA-involved type (types B + C) was significantly more prevalent in ruptured aneurysms (77%). Bleb formation was particular in ruptured aneurysms. As for the treatment, the risk of SCA occlusion and incomplete and attempted operation was particularly high in cases with SCA-involved type. Although SCA aneurysms may grow due to the hemodynamic stress at the opened bifurcation between the PCA and SCA, the neck shifting to the origin of SCA, particularly in ruptured lesions,may suggest some other etiological mechanism. SCA-involved type aneurysms had a high treatment risk of SCA occlusion and tended to incomplete treatment to avoid such ischemic complications.

SUBINTIMAL HEMORRHAGE IN AN UNRUPTURED SUPERIOR CEREBELLAR ARTERY ANEURYSM

An intracranial aneurysm that hemorrhages into the subintimal layer of the blood vessel is a rare clinical entity. Such a hemorrhage is distinct from dissecting aneurysms or pseudoaneurysms of the cerebral circulation and may represent an aneurysm in the process of rupturing. The authors report their experience in the management of a patient who presented with a subintimal hemorrhage of a superior cerebellar aneurysm. A 54-year-old man presented with a progressively worsening headache over the course of 3 days. A noncontrast computed tomographic scan did not demonstrate subarachnoid hemorrhage but was suggestive of a posterior circulation aneurysm. In the absence of subarachnoid hemorrhage on the computed tomographic scan, negative findings for xanthochromia in the cerebrospinal fluid, and no evidence of subarachnoid blood on magnetic resonance imaging, a conventional four-vessel cerebral angiogram was performed, which revealed a right superior cerebellar artery aneurysm. Further evaluation on magnetic resonance imaging demonstrated abnormal signal conforming to the aneurysm wall, suggesting the presence of a contained subintimal hemorrhage. The patient underwent a right frontotemporal craniotomy (half-and-half approach) for clip ligation of the superior cerebellar artery aneurysm. Subintimal hemorrhage of an aneurysm in the absence of subarachnoid hemorrhage may be conceptually considered an aneurysm in the process of rupturing. Thus, aneurysms found in the acute setting may benefit from further workup, such as magnetic resonance imaging or highly selective angiographic evaluation of the aneurysm itself. Timely surgical intervention may prevent otherwise imminent rupture into the subarachnoid space.

Superior cerebellar artery aneurysms treated using the sole stenting approach

✓Endovascular treatment of intracranial aneurysms has evolved since the introduction of detachable coils. Sole stenting is a brand-new technique that has recently emerged as a definitive treatment for saccular or fusiform aneurysms at particular locations. Superior cerebellar artery aneurysms are rare, and few treated cases have been reported. Most of them have been treated surgically, and endovascular cases usually have been managed with occlusion of the parent vessel. The authors report on the first two endovascularly treated cases with complete cure of the aneurysm as well as preservation of the parent vessel and distal circulation via the sole stenting technique. The results together with several aspects of the technique, such as the correction of the angle of the vessel and modification of the shear stress, are discussed.

Superior cerebellar artery aneurysms treated using the sole stenting approach

Endovascular treatment of intracranial aneurysms has evolved since the introduction of detachable coils. Sole stenting is a brand-new technique that has recently emerged as a definitive treatment for saccular or fusiform aneurysms at particular locations. Superior cerebellar artery aneurysms are rare, and few treated cases have been reported. Most of them have been treated surgically, and endovascular cases usually have been managed with occlusion of the parent vessel. The authors report on the first two endovascularly treated cases with complete cure of the aneurysm as well as preservation of the parent vessel and distal circulation via the sole stenting technique. The results together with several aspects of the technique, such as the correction of the angle of the vessel and modification of the shear stress, are discussed.

Superior cerebellar artery aneurysms: incidence, clinical presentation and midterm outcome of endovascular treatment

IntroductionThe aim of this retrospective study was to determine the incidence, clinical presentation and midterm clinical and imaging outcome of endovascular treatment of 34 superior cerebellar artery (SCA) aneurysms in 33 patients.MethodsBetween January 1995 and January 2007, 2,112 aneurysms were treated in our institution, and 36 aneurysms in 35 patients were located on the SCA (incidence 1.7%). Two of three distal SCA aneurysms were excluded. All the remaining 34 SCA aneurysms, of which 22 (65%) were ruptured and 12 (35%) were unruptured, in 33 patients were treated by endovascular techniques. There were 6 men and 27 women ranging from 29–72 years. In 14 patients (42%) multiple aneurysms were present.ResultsInitial angiographic occlusion was (near) complete in 32 aneurysms (94%) and incomplete in 2 aneurysms (6%). Complications leading to permanent morbidity or death occurred in two patients (6.1%, 95% CI 0.6 to 20.60%). Outcome at 6 months follow-up in 31 surviving patients was GOS5 in 26 (84%), GOS4 in 4 (13%) and GOS3 in 1 patient (3%). There were no episodes of (re)bleeding during 118 patient-years of follow-up. The 6-month angiographic follow up in 28 SCA aneurysms and extended angiographic follow-up in 19 showed stable occlusion in 27 aneurysms. No additional treatments were performed.ConclusionSCA aneurysms are rare with an incidence of 1.7% of treated aneurysms at our institution. They are frequently associated with other aneurysms. Endovascular treatment is effective and safe in excluding the aneurysms from the circulation.

Fusiform aneurysm of the superior cerebellar artery: short review article

Fusiform superior cerebellar artery (SCA) aneurysms are quite rare and only 9 cases have been reported in the literature. Fusiform aneurysms are a small group of cerebral aneurysms among the most difficult to treat. The therapeutic approaches in the limited number cited in the literature include surgery and endovascular occlusion. Surgical techniques which have been used are parent artery occlusion, trapping or body clipping of the bleeding site, and wrapping for fusiform aneurysms. Neurological condition, presence of collateral circulation, type and configuration of the aneurysm, and type of the dissection are important factors that predict the course of fusiform SCA aneurysms. We reviewed the literature on fusiform aneurysm of the SCA and report a further case treated surgically.

Ruptured superior cerebellar artery aneurysm in a child with bilateral fibromuscular hyperplasia of the renal arteries

The authors report the case of a pediatric patient with bilateral fibromuscular hyperplasia (FMH) of the renal arteries who sustained a subarachnoid hemorrhage (SAH) caused by the rupture of a superior cerebellar artery aneurysm. The aneurysm was successfully treated with microsurgical clip occlusion. The association between renal artery FMH and aneurysmal SAH is extremely rare and incompletely understood. There are six previously published cases in the English literature; only one case involved direct aneurysm treatment and none involved the posterior circulation. In addition to presenting this case, the authors discuss the complexities involved in treating these patients from a technical and conceptual standpoint.

The endovascular management of superior cerebellar artery aneurysms.

Superior cerebellar artery aneurysms are rare. We present a clinical series of twelve of these aneurysms that were treated exclusively with endovascular coils. A retrospective analysis of a prospectively collected database of cerebral aneurysms treated with coil embolization was performed. Clinical notes and radiological images were reviewed. Twelve superior cerebellar artery aneurysms were treated in eleven patients between 1992 and 2001. Seven patients presented with subarachnoid hemorrhage, two with neurologic deficit, and two had asymptomatic aneurysms. Coiling resulted in complete aneurysm obliteration in six patients and incomplete obliteration in the other six. No subsequent hemorrhage occurred with follow-up between 6 and 119 months (mean follow-up 50 months). Procedural morbidity was one superior cerebellar artery infarct with good recovery. Management morbidity was one middle cerebral artery embolus during a follow-up angiogram that required thrombolysis with a good clinical result. Nine out of 11 patients on follow-up were performing at Glasgow Outcome Scale (GOS) 5. One patient with GOS 3 presented with a poor grade subarachnoid hemorrhage and the other patient with GOS 4 presented with a parenchymal hemorrhage due to an arteriovenous malformation. Endovascular treatment of superior cerebellar artery aneurysms is an effective treatment strategy with low morbidity.

The surgery of ruptured and unruptured cerebral aneurysms using three-dimensional CT angiography without conventional catheter angiography

The object of this study is to assess whether aneurysm surgery can be performed in patients with ruptured and unruptured cerebral aneurysms by using three-dimensional computerized tomography angiography (3D-CTA) alone, without conventional catheter angiography (CCA). We have operated on 153 consecutive patients with ruptured aneurysms and 89 patients with unruptured aneurysms based on 3D-CTA findings since December 1996 and February 1997, respectively. In the cases of ruptured aneurysm, 153 ruptured aneurysms including 62 associated unruptured aneurysms were detected by 3D-CTA. CCA was performed in 7 of 153 patients after they underwent 3D-CTA, which included four dissecting vertebral artery (VA) aneurysms, two basilar artery (BA) tip aneurysms, and one BA–superior cerebellar artery (SCA) aneurysm. In 89 patients with unruptured aneurysms, 101 unruptured aneurysms were detected by 3D-CTA. In 5 of 101 unruptured aneurysms, which included giant or large aneurysms and a case of an aneurysm associated with infarction, CCA was needed. All of the ruptured and unruptured aneurysms were confirmed during surgery and treated successfully. The authors stress that 3D-CTA could replace CCA in the diagnosis of saccular aneurysms and that surgery could be performed in almost all ruptured and unruptured aneurysms by using only 3D-CTA without CCA.

Maladie de Behçet révélée par un anévrisme intracrânien

Introduction.– Mostly venous (95% of all vascular complications), and less frequently arterial (2 to 7% of all cases), vascular complications are commonplace in Behçet's disease (23 to 64% of the patients, depending on the series). Arterial complications are stenosis, occlusions and especially severe due to their unpredictable rupture risk, aneurysms. Intracranial aneurysms associated with Behçet's disease are exceptional. Until now, only ten cases have been published. Exegesis. – We report the case of a 36-year-old patient of Armenian origin in whom the diagnosis of Behçet's disease was made after a subarachnoid hemorrhage caused by the rupture of a left superior cerebellar artery aneurysm. The endovascular treatment of the aneurysm was associated with an immunosuppressive treatment consisting of cyclophosphamide, corticoids and colchicine. Within a 6-month period of follow up the evolution has been favorable. This is the first published case report of Behçet's disease associated with an aneurysm of the posterior circulation treated endovascularly. A review of the literature is also included. Conclusion. – Intracranial aneurysms are an exceptional but nevertheless severe localization of vascular complications in Behçet's disease. As in all other arterial lesions, recurrences are frequent. The treatment involves surgical or endovascular treatment that should be associated with corticoids and immunosuppressive therapy. Colchicine is useful for the prevention of relapses.

Late Thromboembolic Events after Treatment of Intracranial Aneurysms with Guglielmi Detachable Coils

P98 Purpose: Thrombo-embolic complications associated with the endovascular treatment of intracranial aneurysms with Guglielmi Detachable Coils (GDC) generally occur at the time of the procedure or soon after. The purpose of this report is to determine the frequency of late thrombo-embolic events after GDC. Methods: The records of 189 patients who underwent GDC repair of one or more intracranial aneurysms at our institution were reviewed. The occurence of an ischemic event referrable to a coiled aneurysm was determined by clinical, angiographic, and imaging data. Events occuring within 2 days of the endovascular procedure were considered peri-procedural. Kaplan-Meier analysis of ischemic events over time was performed. Results: Two patients suffered documented thrombo-embolic events. One patient presented 5 weeks after coiling with a transient ischemic attack. Angiography demonstrated thrombus on the surface of the coils at the neck of a large ophthalmic artery aneurysm. The second patient presented with a posterior circulation stroke 4 weeks after coiling of a large superior cerebellar artery aneurysm. Angiography showed no significant proximal disease, with thrombus beginning at the neck of the treated aneurysm and extending out both P1 segments. No intra-procedural problems during the initial coiling had occured with either patient. There was no evidence for protrusion of coils into the parent artery in either patient. Both patients had been receiving daily aspirin (325 mg). One additional patient reporting symptoms suggesting possible ischemics event was evaluated and diagnosed as having atypical migraines. The frequency of a clinical thromboembolic event during the first year after coiling (excluding procedural complications) was 1.1%. Conclusions: Thrombo-embolic events may occur as late as 5 weeks after endovascular treatment of aneurysms with GDC.

Posterior circulation aneurysms: Guideline to management

Posterior circulation aneurysms present a difficult challenge because they are located in an exquisitely eloquent and sometimes difficult-to-reach area in the posterior cranial, fossa. Because the basilar artery and the origin of its main branches are located along the anterior aspect of the brainstem, the surgical approaches used to reach such lesions should provide enough space while avoiding undue restriction of the brainstem and cerebellum. A thorough knowledge of the microsurgical anatomy of the posterior fossa and posterior circulation is mandatory for a successful operation. We use the pretemporal approach to deal with small and apparently simple basilar bifurcation aneurysms, as well as for most superior cerebellar artery aneurysms. The transcavernous-transellar approach is performed for large, complex, or low-lying basilar bifurcation aneurysms. A lateral skull base approach is usually performed to operate on aneurysms located on the mid-third of the basilar artery and at the vertebrobasilar junction. We usually perform the presigmoid supra- and infratentorial approach for mid-third basilar aneurysms. Vertebrobasilar junction aneurysms may also be approached through a suboccipital-transcondylar approach. PICA aneurysms are approached through either a retrosigmoid or a far-lateral approach, depending on their exact location in the posterior fossa. The surgical approach and procedure should be tailored to each specific aneurysm, taking into account the aneurysm's size, location, and relationships with surrounding neurovascular structures, as well as the regional blood flow dynamics.