Characteristics and surgical treatment of dolichoectatic and fusiform aneurysms

Research progress on vertebrobasilar dolichoectasia

Vertebrobasilar dolichoectasia (VBD) is a rare disease characterized by significant expansion, elongation, and tortuosity of the vertebrobasilar arteries. Current data regarding VBD are very limited. Here we systematically review VBD incidence, etiology, characteristics, clinical manifestations, treatment strategies, and prognosis. The exact incidence rate of VBD remains unclear, but is estimated to be 1.3% of the population. The occurrence of VBD is thought to be due to the cooperation of multiple factors, including congenital factors, infections and immune status, and degenerative diseases. The VBD clinical manifestations are complex with ischemic stroke as the most common, followed by progressive compression of cranial nerves and the brain stem, cerebral hemorrhage, and hydrocephalus. Treatment of VBD remains difficult. Currently, there are no precise and effective treatments, and available treatments mainly target the complications of VBD. With the development of stent technology, however, it may become an effective treatment for VBD.

Combined endovascular and surgical treatment of fusiform aneurysms of the basilar artery: technical note

BACKGROUND

To present the combined treatment of fusiform basilar artery aneurysms consisting of a surgical posterior fossa decompressive craniectomy and ventriculoperitoneal (VP) shunt operation at the same sitting, before the endovascular procedure with telescopic stenting of the aneurysmatic vessel segment in four cases.

METHODS

Combined treatment involving surgical procedure consisting of ventriculoperitoneal shunt placement for hydrocephalus and an occipital bone craniectomy and C1 vertebrae posterior laminectomy to decompress the posterior fossa in the same session. After surgery, the patients were loaded with acetylsalicylic acid and clopidogrel, and then the endovascular treatment was performed.

RESULTS

All of the procedures were performed successfully without technical difficulty. The patients tolerated the procedures well and all cases showed remodelling with the overlapping stent technique. The patients were discharged home with baseline neurological situation and computed tomography (CT) angiography was performed at the 3rd month.

CONCLUSION

This technique is a safer endovascular approach to treating symptomatic fusiform basilar artery aneurysms by protecting patients from both the haemorrhagic complications of anticoagulant therapy and thrombotic complications due to the interruption of anticoagulant therapy, while treating the hydrocephalus and compression by surgical means.

Dolichoectasia of the vertebral basilar and internal carotid arteries: A case report and literature review

Background:

Dolichoectasia is a rare disorder of the cerebral vasculature consisting of vascular elongation, widening, and tortuosity, usually involving the vertebral and basilar arteries. Its neurological symptoms and signs are highly variable.

Case Description:

We present a case of dolichoectasia of the vertebrobasilar system in a patient with a long standing history of multiple falls. Repeat neuroimaging revealed an increase in size of the dolichoectatic segment. In addition, a new fusiform dilatation of the contralateral petrous segment of the internal carotid artery and isolated ventriculomegaly had developed.

Conclusion:

Vertebrobasilar dolichoectasia can cause multiple clinical manifestations, with hydrocephalus being less common. In addition, having dolichoectasia of both posterior and anterior circulation is extremely rare.

Bypass and flow reduction for complex basilar and vertebrobasilar junction aneurysms

BACKGROUND

Giant aneurysms of the vertebral and basilar arteries are formidable lesions to treat.

OBJECTIVE

To evaluate the long-term outcomes of patients with vertebrobasilar aneurysms treated with extracranial-intracranial bypass and flow reduction.

METHODS

We retrospectively reviewed a prospective database of aneurysms cases treated between December 1993 and August 2011.

RESULTS

Eleven patients (8 male, 3 female) with 12 aneurysms were treated. There were 3 basilar apex aneurysms, 2 aneurysms of the basilar trunk, and 7 vertebrobasilar junction aneurysms. There were 5 saccular and 7 fusiform aneurysms. All patients underwent extracranial-intracranial bypass and vessel occlusion. Flow was reversed or reduced by complete (n = 6) or partial occlusion of the basilar artery (n = 3) or by occlusion of the vertebral arteries distal to the posterior inferior cerebellar artery (n = 3). Postoperatively (mean follow-up, 71.6 months; range, 4-228; median, 49 months), the bypass patency rate was 92.3% (12/13). The perioperative mortality rate for the initial treatment was 18.2% (2/11). In 4 cases, the aneurysms continued to grow and required further treatment; after re-treatment, 3 of these patients died. Of the initial 11 patients, 6 were treated successfully and 5 died. The mean preoperative modified Rankin Scale score was 2.1 (range, 1-3; median, 2). At last follow-up for all patients, the mean modified Rankin Scale score was 3.45 (range, 1-6; median, 3) and 2.5 (range, 1-4; median, 2.5) for the 6 long-term survivors.

CONCLUSION

Vertebrobasilar aneurysms are challenging lesions with limited microsurgical or endovascular options. Despite aggressive surgical treatment, the long-term outcome remains poor for most patients.

Management of ruptured dissecting intracranial aneurysms in infants: report of four cases and review of the literature

BACKGROUND

Intracranial cerebral aneurysms in the pediatric population are infrequent, and those occurring in infants less than 1 year old are extremely rare. Of intracranial aneurysms in children, dissecting aneurysms are the most common type seen. While spontaneous dissecting aneurysms usually present with ischemia, hemorrhage can also occur.

METHODS

A retrospective review of our patients revealed that from July 1, 2007 to June 30, 2012, four infants were treated for ruptured distal dissecting intracranial aneurysms at Texas Children's Hospital. Mycotic aneurysms and collagen vascular disorder were excluded in all four cases. All patients presented in our series presented with subarachnoid hemorrhage, and three had intraventricular hemorrhage. All patients underwent conventional catheter angiography for diagnosis. All patients in this series were managed in the acute or subacute period with surgical or endovascular trapping without distal bypass procedures. All four patients tolerated sacrifice of the parent vessels feeding these distal aneurysms well.

CASE REPORT AND REVIEW OF LITERATURE

We describe the presentation and management of these rare cases and then review the current literature on the management of these dissecting aneurysms in infants.

Awake craniotomy for trapping a giant fusiform aneurysm of the middle cerebral artery

BACKGROUND

Giant fusiform aneurysms of the distal middle cerebral artery (MCA) are rare lesions that, because of the absence of an aneurysm neck and the presence of calcified walls and partial thrombosis, can be difficult to clip without sacrificing the parent vessel. Moreover, when the aneurysm is located in the dominant hemisphere, it is not possible to test language and cognitive functions during surgical intervention, making the closure of the parent vessel extremely dangerous.

CASE DESCRIPTION

A 46-year-old woman presented with a one-year history of frontal headache without neurological deficit. A magnetic resonance imaging and an angiography showed a giant fusiform aneurysm of the left M2 tract. Because of the location and the absence of a neck, the aneurysm was considered difficult to coil and not amenable to preoperative balloon occlusion; thus, the patient was a candidate for surgical treatment. After a preoperative psychological evaluation, patient underwent awake craniotomy with the asleep-awake-asleep technique. A standard left pterional approach was performed to expose the internal carotid artery, the MCA and the aneurysm originating from the frontal branch of the MCA. Neurological examination responses remained unchanged during temporary parent artery occlusion, and trapping was successfully performed.

CONCLUSIONS

Awake craniotomy is a useful option in intracranial aneurysm surgery because it permits neurological testing before vessels are permanently clipped or sacrificed. With the asleep-awake-asleep technique, it is possible to perform a standard pterional craniotomy, which allows good exposure of the vascular structures without cerebral retraction.

Pediatric intracranial aneurysms: current national trends in patient management and treatment

PURPOSE

Pediatric intracranial aneurysms constitute a medical disease process with many unique features that present unique challenges in orchestrating their treatment. Conflicts exist in pediatric aneurysm literature as to whether endovascular therapy is equivalent to surgical therapy in assuring durable aneurysm obliteration in this population.

MATERIALS AND METHODS

The national Healthcare Cost and Utilization Project (HCUP) Kid's Inpatient Dataset was queried using the HCUPnet system. Overall trends in length of stay (LOS), associated charges, and in-hospital deaths were analyzed for both subarachnoid hemorrhage (SAH) and nonruptured aneurysms from 2000 to 2009. Trends in the type of procedure, associated LOS, and charges were analyzed for SAH from 2003 to 2009. A p value <0.05 was considered statistically significant.

RESULTS

Mean LOS for SAH patients was an additional 7-10 days compared to patients discharged with nonruptured aneurysms. Costs of surgery showed a slight increase, while endovascular procedures also rose 50 % from 2006 to 2009. Interestingly, mean length of stay increased for endovascular procedures from 16.5 to 17.2 days and decreased for surgical procedures from 20.4 to 14.7 days (p < 0.001).

CONCLUSIONS

First, in-hospital mortality and hospital length of stay for pediatric subarachnoid hemorrhage have not significantly declined since 1997. Second, in-hospital charges for the management of both ruptured and nonruptured aneurysms rose by over 200 % from 2000 to 2009. Surgical procedures saw a 6 % increase in price, while endovascular procedures sharply rose in costs by 50 %. Finally, endovascular therapy has increased in utilization, while the frequency of surgical therapy has not changed significantly since 2003.

Dolichoectasia diagnostic methods in a multi-ethnic, stroke-free cohort: results from the northern Manhattan study

BACKGROUND AND PURPOSE

Dolichoectasia (DE) is a vasculopathy that consists of abnormal elongation and dilatation of arteries. The objective of this study is to evaluate the frequency of DE in an unselected population and assess different diagnostic methods.

METHODS

The Northern Manhattan Study is a multiethnic population based cohort of stroke-free participants. The definition proposed for DE was total cranial volume (TCV)-adjusted arterial diameter ≥2 SD. Other methods studied included visual assessment, unadjusted arterial diameters cutoff, Smoker's criteria and basilar artery (BA) volume.

RESULTS

A total of 718 subjects were included in the analysis (mean age 71.6 ± 8.0 years, 40% men, 61% Hispanic). Using the TCV-adjusted DE definition, 19% of the sample had at least one dolichoectatic artery. In 7% of the subjects, two or more arteries were affected. The BA was the most common dolichoectatic artery. Reproducibility for arterial diameter measurements was good to excellent (.70-.95), while for visual assessment ranged from fair to good (.49-.79).

CONCLUSIONS

A TCV-adjusted intracranial arterial diameter ≥2 SD is proposed as a useful DE definition. The variability in the prevalence of DE depending on the methods used underscores the need to agree on a reliable, universal definition of DE.

["Water Hammer effect": a rare mechanism of hydrocephalus]

We are reporting a case of functional hydrocephalus in a 66-year-old male patient presenting for gait disturbance. The etiology of the disease is a cerebrospinal fluid flow disturbance due to an ectatic basilar artery at the level of Monro foramen. Different pathophysiological mechanisms are discussed below.

Endovascular Treatment of Basilar Trunk Saccular Aneurysms

Basilar artery (BA) trunk aneurysms are rare and still remain a formidable surgical challenge. The purpose of this retrospective study was to report the clinical entities and results of endovascular surgery of BA trunk saccular aneurysms. Between 1995 and 2009, 14 patients with 14 BA trunk saccular aneurysms underwent endovascular surgery. Six patients presented subarachnoid hemorrhage (SAH), three patients had another associated aneurysm which developed SAH, one patient presented with mass effect to the brain stem, and four patients were incidentally discovered. Five ruptured and seven unruptured aneurysms were successfully treated by endovascular surgery. Another one incompletely embolized aneurysm had grown to huge size five years later and the patient underwent a Hunterian ligation with a radial artery graft between the extracranial vertebral artery and the posterior cerebral artery. In one ruptured case, we attempted neck clipping, but this was abandoned because of concern for neck tearing by clipping. The aneurysm was embolized using detachable coils later. BA trunk aneurysms showed characteristic features such as so-called lateral aneurysm (43%), multiple aneurysms (43%) and four BA fenestrations (36%). The unusual high incidence of associated various vascular anomalies suggests that focal wall weakness must be based on the mechanism of aneurysm initiation on the BA trunk. Most patients presented with SAH. Pre-treatment neurological state was predictive for clinical outcome. Endovascular surgery is an effective therapeutic alternative that is associated with low morbidity and mortality rates, and should be considered the first choice treatment.

Intracranial aneurysms: review of current treatment options and outcomes

Intracranial aneurysms are present in roughly 5% of the population, yet most are often asymptomatic and never detected. Development of an aneurysm typically occurs during adulthood, while formation and growth are associated with risk factors such as age, hypertension, pre-existing familial conditions, and smoking. Subarachnoid hemorrhage, the most common presentation due to aneurysm rupture, represents a serious medical condition often leading to severe neurological deficit or death. Recent technological advances in imaging modalities, along with increased understanding of natural history and prevalence of aneurysms, have increased detection of asymptomatic unruptured intracranial aneurysms (UIA). Studies reporting on the risk of rupture and outcomes have provided much insight, but the debate remains of how and when unruptured aneurysms should be managed. Treatment methods include two major intervention options: clipping of the aneurysm and endovascular methods such as coiling, stent-assisted coiling, and flow diversion stents. The studies reviewed here support the generalized notion that endovascular treatment of UIA provides a safe and effective alternative to surgical treatment. The risks associated with endovascular repair are lower and incur shorter hospital stays for appropriately selected patients. The endovascular treatment option should be considered based on factors such as aneurysm size, location, patient medical history, and operator experience.

Middle cerebral artery aneurysms in children: case series and review

OBJECT

Pediatric intracranial aneurysms are rare lesions that differ from their adult counterparts. Aneurysms involving the middle cerebral artery (MCA) are particularly challenging to treat in children, as they are often fusiform and cannot undergo direct clipping alone. The authors recently treated a patient with a heavily calcified, dysplastic, left-sided MCA aneurysm. The present study was performed to evaluate the authors' previous operative and follow-up experience with these difficult lesions.

METHODS

The authors performed a review of a prospectively maintained database of all aneurysms treated at Methodist Hospital in Indianapolis, Indiana, from January 1990 through November 2010. Relevant operative notes, clinical charts, and radiological reports were reviewed for all patients 18 years of age or younger.

RESULTS

A total of 2949 patients with aneurysms were treated over the study period, including 28 children (0.95%). Seven children harbored MCA aneurysms. Five of these 7 aneurysms (71.4%) were fusiform. Two patients were treated with direct clipping, 2 underwent parent vessel occlusion without bypass, and 3 underwent aneurysm trapping with extracranial-intracranial vessel bypass. Long-term follow-up data were available in 6 cases. All 6 patients had a 1-year follow-up Glasgow Outcome Scale score of 5. Long-term radiological follow-up was available in 4 patients. One patient required a reoperation for a recurrent aneurysm 4 years after the initial surgery.

CONCLUSIONS

Middle cerebral artery aneurysms in children are often fusiform, giant, and incorporate the origins of proximal artery branches. Direct clipping may not be possible; trapping of the lesion may be required. Children seem to tolerate surgical trapping with or without bypass extremely well. Aggressive therapy of these rare lesions in children is warranted, as even patients presenting with a poor clinical grade may have excellent outcomes. Long-term surveillance imaging is necessary because of the risk of aneurysm recurrence.

Endovascular Treatment of Posterior Circulation Fusiform Aneurysms: Single-Center Experience in 31 Patients

BACKGROUND:

Posterior circulation fusiform aneurysms are rare but difficult to treat.

OBJECTIVE:

To report our experience with endovascular treatment of posterior circulation fusiform aneurysms.

METHODS:

A retrospective review of our prospectively maintained database identified all posterior circulation fusiform aneurysms treated by endovascular approach over a 6-year period. Clinical charts, procedural data, and angiographic results were reviewed.

RESULTS:

From March 2004 to March 2010, 31 patients were identified: 11 asymptomatic patients, 9 who presented with a subarachnoid hemorrhage, 6 with a stroke, and 5 with a mass effect. All but 1 patient (97%), who died before being treated, were successfully treated by parent artery occlusion (n = 10), stenting plus coiling (n = 10), or stenting alone with conventional or flow-diverting stents (n = 10). Twenty-two patients showed a good or an excellent outcome (73%); 3 had a fair or a poor outcome (10%); and 5 patients died (17%). These 8 patients initially presented with severe subarachnoid hemorrhage or mass effect. Procedure-related morbidity includes only one patient who kept a worsening of cranial nerve palsies. There was no definitive procedure-related morbidity or mortality. Immediate aneurysm occlusion was incomplete in 20 cases (67%) and complete in 10 cases (33%). Mean follow-up of 20 months in 23 patients showed 12 further thromboses, 9 stable results, and 2 flow reductions. Final results included 19 complete occlusions (83%) and 4 incomplete occlusions (17%).

CONCLUSION:

Posterior circulation fusiform aneurysms may be treated by different endovascular approaches with satisfying clinical and anatomical results in most cases. However, patients who present with severe subarachnoid hemorrhage or mass effect still have a poor prognosis.

The challenge of managing fusiform basilar artery aneurysms: from acute ischemic stroke to a massive subarachnoid hemorrhage

We present the case of a patient with acute brain stem ischemic stroke who was found to have a fusiform basilar aneurysm with a thrombus within the dilated vessel. Three days after the ischemic stroke, the patient had a massive subarachnoid hemorrhage and died. This case illustrates the difficulties in the acute management of ischemic events in patients with basilar fusiform aneurysms, because the natural history of this disease encompasses both bleeding and thrombosis.

Surgical Treatment of a Large Fusiform Distal Anterior Cerebral Artery Aneurysm With In Situ End-to-Side A3—A3 Bypass Graft and Aneurysm Trapping

BACKGROUND AND IMPORTANCE:

Large fusiform aneurysms of the distal anterior cerebral territory are extremely rare and can be particularly challenging to treat. The circumferential pathology of fusiform lesions renders stand-alone clip or coil ablation unsatisfactory, and the deep, narrow corridor augments the difficulty of surgical approaches. In this setting, bypass procedures may be used to both treat the aneurysm definitively and preserve distal parent artery flow. We report a rare case of a large fusiform A3 aneurysm treated with trapping and concomitant end-to-side A3:A3 bypass.

CLINICAL PRESENTATION:

A 52-year-old man was evaluated after losing consciousness and experiencing a fall. A noncontrast computed tomography scan revealed a focal area of hemorrhage above the body of the corpus callosum, and computed tomography angiography showed a fusiform aneurysm of the right A3 artery. To treat the aneurysm definitively and preserve distal vessel flow, the patient was taken to surgery in anticipation of aneurysm ablation and cerebrovascular bypass. A large, fusiform right A3 aneurysm was identified. Intraoperative flow measurement demonstrated poor collateral circulation. The aneurysm was trapped with clips, and a right-to-left A3:A3 end-to-side in situ bypass was performed. Aneurysm occlusion and preserved distal vessel flow were confirmed with intraoperative angiography.

CONCLUSION:

Large fusiform aneurysms in the distal anterior cerebral artery region are rare, and the anatomy of these lesions and their vascular location render stand-alone surgical management technically challenging. End-to-side A3:A3 bypass combined with aneurysm trapping represents a feasible treatment strategy for lesions in this location.

Ruptured dissecting cerebral aneurysms in young people: report of three cases

Intracranial arterial aneurysms in the pediatric population are rare. Among these, dissecting aneurysms are the most frequent, followed by saccular, infectious, and posttraumatic. It is widely known that aneurysmal rupture is uncommon in the first two decades of life. Spontaneous dissecting aneurysms (SDAs) of the middle cerebral artery (MCA) affecting young individuals most frequently present as occlusive syndrome with ischemia, although bleeding and subarachnoid hemorrhage can also occur. Between March 2006 and January 2008, three young patients (20 months, 8 and 20 years old) were surgically treated for MCA SDA in the Neurosurgical Department of "12 de Octubre" Hospital of Madrid. These patients showed hemorrhage as primary radiological finding, and all of them underwent surgical operation. Aneurysms were always treated by trapping, with aneurysmectomy in one case, but no distal extra-intracranial (EC-IC) bypass was performed. In two cases, the histological examination of the aneurysm's wall evidenced signs of subintimal dissection with widespread disruption of the internal elastic lamina and media with neointima formation and intramural hemorrhage. Although bleeding is an uncommon presenting sign of SDAs, they should be suspected in young people showing hemorrhage at CT scan. Early surgical treatment and, if possible, preoperative neuroimaging evaluation of intracranial vessels should be performed to reduce the mortality in these patients despite a higher postoperative morbidity. From a technical point of view, surgical trapping of the aneurysm seems to be a reasonable treatment strategy especially in an emergency basis. However, whenever possible, an EC-IC bypass could help diminish the ischemic morbidity associated with these aneurysms.

Hyperperfusion syndrome after neck clipping of a ruptured aneurysm on a dolichoectatic middle cerebral artery

A 40-year-old female presented with sudden onset of severe headache and vomiting due to subarachnoid hemorrhage. Angiography demonstrated a saccular aneurysm on a dolichoectatic left middle cerebral artery (MCA) and delayed filling of the MCA. Magnetic resonance imaging showed a partially thrombosed giant aneurysm on the dolichoectatic MCA. An intentionally delayed operation was performed, during which the neck of the aneurysm was successfully clipped. The patient exhibited aphasia 48 hours after surgery. Single-photon emission computed tomography revealed hyperperfusion in the territory of the left MCA. The patient's blood pressure was maintained normotensively, and her symptoms gradually improved. She returned to work 1 month after surgery. The saccular aneurysm was formed on the dolichoectatic MCA, presumably due to an abnormal arterial wall and hemodynamic stress. The preoperative hypoperfusion might have been caused not only by the giant aneurysm, but also to some degree by the dolichoectatic MCA. After neck clipping, the increase in blood flow might have caused hyperperfusion.

Endovascular treatment of a fusiform cerebral aneurysm by stenting alone. Two case reports and literature review

This paper illustrates two cases of stent-in-stenting treatment of unruptured, symptomatic, fusiform intracerebral aneurysms. Two unruptured symptomatic fusiform intracerebral aneurysms were treated by the stent-in-stent only technique. The first patient, a 35-year-old woman, had a partially thrombosed fusiform aneurysm in the left carotid siphon with the chief complaint of headache and left ophthalmoplegia. The second patient, a 60-year-old man, had a symptomatic fusiform aneurysm of the left V4 with recurrent transient ischemic attacks. No cervical trauma or infection was present in either patient. A CT, CTA and DSA were performed on hospital admission. Both patients were previously premedicated with Clopidrogel + ASA for five days before treatment. By DSA, both patients were treated under general anesthesia with a heparin protocol plus ASA (500mg) at stent placement. A double stent-in stent was placed in both patients. Post-intervention medical therapy was clopridogel and ASA for three months, then aspirin (100mg) daily for six months. CTA and DSA were performed at six and 12 months. Both stents were positioned without any difficulty and could be navigated within cerebral arteries without any exchange procedure, and thanks to their retractability, they were accurately positioned. No bleeding at post-treatment CT was noted. At 12 months follow-up, a complete disappearance of the aneurysm and preservation of the parent vessel was observed for both patients. No procedure-related complication occurred. No intra-stent stenosis or intimal hyperplasia was observed. Stenting for fusiform aneurysms is a safe procedure without complications. Medical therapy pre-post procedure associated with follow-up is necessary to prevent/establish the incidence of occlusion.

Death associated with an unruptured giant intracranial aneurysm

Deaths due to or associated with unruptured giant intracranial aneurysms are extremely rare. We describe a case of a sudden death associated with an unruptured giant vertebrobasilar aneurysm in a symptomatic 18-year-old male. Post-mortem examination revealed three giant fusiform and thrombosed aneurysms (vertebrobasilar junction, internal carotid arteries), an old infarct with some sub-acute changes in the brain stem and medulla, an incipient pneumonia, and a high blood alcohol concentration (2.4 o/oo). The association of these findings suggest the role of a multi-factorial respiratory dysfunction as a pathophysiological mechanism leading to death. In fatal cases related to giant intracranial aneurysm, a number of triggers and contributing factors, with potential medico-legal implications, must be appropriately considered in the chain of events leading to death.

Reconstructive endovascular treatment of intracranial fusiform aneurysms: a 1-stage procedure with stent and balloon

BACKGROUND AND PURPOSE

Intracranial fusiform aneurysms, which incorporate the branch vessel and require salvaging of the parent vessel, are difficult to manage. The goal of this study was to evaluate the efficacy of reconstructive endovascular treatment of intracranial fusiform aneurysms by using a 1-stage procedure with a stent and balloon.

MATERIALS AND METHODS

During a 3-year period, 20 patients with 20 intracranial fusiform aneurysms were treated by using a 1-stage procedure involving a balloon and stent. Subarachnoid hemorrhage was present in 15 patients. Five aneurysms were located in the anterior circulation and 15, in the posterior circulation. Clinical outcomes and periprocedural complications were evaluated in all patients. The extent of coil packing was evaluated by control angiography after embolization and classified as either complete occlusion or partial occlusion. Angiography was performed 6, 12, and 24 months after embolization to evaluate stent patency and coil packing.

RESULTS

The 1-stage procedure by using a combination of balloon and stent was technically successful in all patients. There were no complications related to the procedure, complete occlusion was obtained in 16 patients, and partial occlusion, in 4 patients. All patients recovered well except for 2 who died due to causes unrelated to the procedure. Clinical follow-up was performed in all surviving patients at a mean of 12.3 months (range, 7-24 months), and angiography showed that the patent parent arteries were free of aneurysm recanalization or in-stent stenosis.

CONCLUSIONS

This 1-stage procedure may provide a feasible and safe treatment strategy for the management of intracranial fusiform aneurysms that are not amenable to deconstructive embolization.

Successful endovascular reconstruction of acutely ruptured pseudoaneurysm of the vertebral artery, complicated by isolated vertebrobasilar circulation and symptomatic vasospasm

The management of a ruptured pseudoaneurysm of intracranial vertebral artery (VA), which is the sole supplier to an isolated vertebrobasilar system, is challenging. The authors report on such a case in a 49-year-old man who suffered a grade III subarachnoid hemorrhage (SAH) caused by a dissecting fusiform pseudoaneurysm of the left VA. The right VA terminated in the posterior inferior cerebellar artery and posterior communicating arteries were absent. The patient developed symptoms consistent with vasospasm on day 9 after SAH, which was treated by intra-arterial vasolytic therapy, followed by stent placement and "in-stent" balloon angioplasty. Angiography 2 weeks later showed near-complete resolution of the pseudoaneurysm. At discharge, the patient's modified Rankin score was one. In this complicated case in which an isolated vertebrobasilar circulation precluded parent vessel sacrifice, we detail the successful management using a combination of intra-arterial vasolytic therapy, stent reconstruction, and balloon angioplasty.

Peripheral intracranial aneurysms: management challenges in 60 consecutive cases

Object

The authors report the management and outcomes of 55 patients with 60 intracranial aneurysms arising distal to the major branch points of the circle of Willis and vertebrobasilar system.

Methods

Between July 1997 and December 2006, the authors' neurovascular service treated 2021 intracranial aneurysms in 1850 patients. The database was reviewed retrospectively to identify peripherally located intracranial aneurysms. Aneurysms that were mycotic and aneurysms that were associated with either an arteriovenous malformation or an atrial myxoma were excluded from review.

Results

The authors encountered 60 peripheral intracranial aneurysms in 55 patients. There were 42 small, 7 large, and 11 giant lesions. Forty-one (68%) were unruptured, and 19 (32%) had bled. Fifty-three aneurysms were treated surgically by using direct clip reconstruction in 26, trapping or proximal occlusion with distal revascularization in 21, excision with end-to-end anastomosis in 3, and circumferential wrap/clip reconstruction in 3. Coils were used to treat 6 aneurysms, and 1 was treated by endovascular parent artery occlusion. Overall, 49 patients had good outcomes, 4 were left with new neurological deficits, and 2 died.

Conclusions

Peripherally situated intracranial aneurysms are rare lesions that present unique management challenges. Despite the fact that in the authors' experience these lesions were rarely treatable with simple clipping of the aneurysm neck or endovascular coil occlusion, preservation of the parent artery was possible in most cases, and the majority of patients had a good outcome.

In vivo assessment of rapid cerebrovascular morphological adaptation following acute blood flow increase

OBJECT

Pathological extremes in cerebrovascular remodeling may contribute to basilar artery (BA) dolichoectasia and fusiform aneurysm development. Factors regulating cerebrovascular remodeling are poorly understood. To better understand hemodynamic influences on cerebrovascular remodeling, we examined BA remodeling following common carotid artery (CCA) ligation in an animal model.

METHODS

Rabbits were subjected to sham surgery (3 animals), unilateral CCA ligation (3 animals), or bilateral CCA ligation (5 animals). Transcranial Doppler ultrasonography and rotational angiography were used to compute BA flow, diameter, wall shear stress (WSS), and a tortuosity index on Days 0, 1, 4, 7, 14, 28, 56, and 84. Basilar artery tissues were stained and analyzed at Day 84. Statistical analysis was performed using orthogonal contrast analysis, repeated measures analysis of variance, or mixed regression analysis of repeated measures. Statistical significance was defined as a probability value < 0.05.

RESULTS

Basilar artery flow and diameter increased significantly after the procedure in both ligation groups, but only the bilateral CCA ligation group demonstrated significant differences between groups. Wall shear stress significantly increased only in animals in the bilateral CCA ligation group and returned to baseline by Day 28, with 52% of WSS correction occurring by Day 7. Only the bilateral CCA ligation group developed significant BA tortuosity, occurring within 7 days postligation. Unlike the animals in the sham and unilateral CCA ligation groups, the animals in the bilateral CCA ligation group had histological staining results showing a substantial internal elastic lamina fragmentation.

CONCLUSIONS

Increased BA flow results in adaptive BA remodeling until WSS returns to physiological baseline levels. Morphological changes occur rapidly following flow alteration and do not require chronic insult to affect substantial and significant structural transformation. Additionally, it appears that there exists a flow-increase threshold that, when surpassed, results in significant tortuosity.

Surgical Treatment of Giant Intracranial Aneurysms: Current Viewpoint

Objective:

Despite new endovascular techniques and technological advances in microsurgery, the treatment of giant intracranial aneurysms is still a daunting neurosurgical task. Many of these aneurysms have a large, calcified neck, directly involve parent and collateral branches, and are partly thrombosed. In this retrospective review, we focused our analysis on the indications for high-flow, extracranial-intracranial (EC-IC) bypass surgery using a saphenous vein graft.

Methods:

A series of 130 patients were treated between 1990 and 2004; 31 patients were managed endovascularly, and 99 patients were treated microsurgically (surgical clipping in 58 patients and high-flow EC-IC bypass followed by aneurysm trapping in 41 patients). We examined the patients’ clinical records and pre- and postoperative case notes for cerebral angiographic examinations. Graft patency was verified with cerebral angiography, computed tomographic angiography, Doppler ultrasound, or graft palpation.

Results:

The high-flow EC-IC bypass was used for all surgically treated prepetrous aneurysms (3 patients), intracavernous aneurysms (1 patient), intracavernous aneurysms with subarachnoid extension (23 patients), as well as for some supraclinoid aneurysms (12 of the 32 patients). It was also used for 1 of the 9 aneurysms located in the carotid bifurcation and 2 of 5 vertebrobasilar circulation aneurysms. Of the 58 patients managed by surgical clipping, 4 (6.9%) died, and 51 (94.4%) improved. Of the 41 patients managed with high-flow EC-IC bypass, 4 (9.8%) died and 34 (91.9%) improved. Graft patency at the follow-up examination was 92.7%.

Conclusion:

The “gold standard” for the treatment of giant aneurysms remains surgical clipping. When direct surgical clipping or endovascular repair is contraindicated, the high-flow EC-IC bypass is a viable surgical option.

Is an angiographically obliterated aneurysm always secure?

OBJECTIVE

Conventional cerebral angiography is the standard examination used to confirm aneurysm obliteration. Intraoperative indocyanine green (ICG) video angiography has recently been introduced as a valuable tool that is comparable to catheter intraoperative angiography. Intraoperative imaging evaluation is especially useful when complex aneurysm features are present, making direct clipping challenging. The aim of these angiographic evaluations is to assess parent vessel patency and to confirm lesion obliteration. However, there have been recent reports of growth or even rupture of angiographically obliterated aneurysms.

CLINICAL PRESENTATION

We report two patients in whom ICG video angiography falsely indicated that a clipped aneurysm was secure.

INTERVENTION

Both patients underwent direct clipping of unruptured aneurysms. ICG video angiography was performed, showing absence of residual filling of the sac. After incising the aneurysm dome, slow but significant dye extravasation was demonstrated. In the first patient, this occurred as a result of incomplete clipping of a wide aneurysm neck that was difficult to visualize; in the second patient, it occurred as a result of atheroma at the neck not allowing complete closure of the clip blades. This finding prompted clip readjustment and placement of an additional reinforcing clip in the two patients, respectively.

CONCLUSION

We demonstrate false indication of aneurysm obliteration by intraoperative video angiographic evaluation using ICG. It is possible that this limitation would also apply to catheter angiography. If certainty of complete exclusion of the aneurysm through opening the dome is not achieved, long-term follow-up angiographic evaluation would be strongly advised.

Endovascular treatment of giant serpentine aneurysms

Giant serpentine aneurysms are fusiform partially thrombosed aneurysms with a separate outflow tract to normal distal cerebral vessels. Three patients with giant serpentine aneurysms of the anterior and middle cerebral arteries were treated with endovascular occlusion of the aneurysmal lumen with coils or glue after balloon test occlusion of the involved vessel. In all 3 patients, leptomeningeal collateral circulation was sufficient to prevent distal ischemia.

Circumferential and fusiform intracranial aneurysms: reconstructive endovascular treatment with self-expandable stents

INTRODUCTION

We report our experience with endovascular treatment (EVT) of circumferential and fusiform intracranial aneurysms by a reconstructive approach with self-expandable stents.

METHODS

A retrospective review of our prospectively maintained database identified all circumferential and fusiform aneurysms treated by a reconstructive endovascular approach over a 3-year period. Clinical charts, procedural data, and angiographic results were reviewed.

RESULTS

From April 2004 to May 2007, 13 patients were identified, of whom 12 were asymptomatic and 1 presented with a subarachnoid hemorrhage. Two patients with an aneurysm <or=2 mm were treated by stent-within-stent placement without coiling (group 1). In 11 patients with a larger aneurysm, stenting with subsequent coiling was performed (group 2). In this latter approach, a balloon was temporarily inflated within the stent to ensure safe coil delivery. All patients showed an excellent clinical outcome. Asymptomatic procedural complications occurred in three patients, two with cervical internal carotid artery dissection and one with retroperitoneal hematoma. In patients of group 1, the aneurysm had completely disappeared at 6 months. In patients of group 2, aneurysm occlusion was complete in three and incomplete in eight. Follow-up angiography in 12 patients showed four with further thrombosis, six with stable results, and two with minor recanalization.

CONCLUSION

Circumferential and fusiform intracranial aneurysms may be treated by a reconstructive endovascular approach with self-expandable stents. In small aneurysms, a stent-within-stent technique is effective, whereas stenting and subsequent coiling is indicated in larger aneurysms. This therapeutic protocol is associated with good clinical and anatomical results.

Case of unusual presentation of fusiform aneurysm of the basilar artery

OBJECTIVE

To describe a case of a fusiform aneurysm of the basilar artery presented as a pontine infarct and 2 days later as a subarachnoid hemorrhage caused by the rupture of the same aneurysm.

DESIGN

Case report.

SETTING

Tertiary-care hospital.

BACKGROUND

Fusiform aneurysm of cerebral vessels is a rare pathology that presents with ischemic stroke, subarachnoid hemorrhage, or mass effect. Ischemia and subarachnoid hemorrhage in the same patient 2 days apart, to our knowledge, was not reported before.

SUBJECT

A 55-year-old Hispanic man with history of untreated hypertension and alcohol abuse presented with acute onset of right hemiparesis and dysarthria. On day 2 of his hospital admission, he developed arrhythmia and loss of consciousness. The patient expired from cardiac arrest on day 4 of his hospitalization. Initial head computed tomography scan showed dolichoectatic basilar artery and marked calcification of internal carotid arteries (ICA) and middle cerebral arteries (MCA). Brain magnetic resonance imaging showed left upper pons infarct 2 cm in diameter. Magnetic resonance angiography confirmed presence of a fusiform aneurysm of the basilar artery. Head computed tomography scan at the time of clinical deterioration on day 2 of hospital admission showed subarachnoid bleeding and significant brain edema. Autopsy revealed a ruptured basilar artery aneurysm with thrombus in the lumen and left pontine infarct. Microscopic examination of fusiform aneurysm showed atherosclerosis of the aneurysmal wall and attenuation and inflammation at the rupture site.

CONCLUSIONS

We hypothesize that in our case, pontine infarct had developed because of occlusion of pontine perforators by a thrombus within an aneurysm, and subarachnoid hemorrhage had developed secondary to a rupture of weakened by inflammatory changes aneurysmal wall. We also hypothesize that in our case, ischemic stroke and subsequent subarachnoid hemorrhage may represent different stages of the same process of atherosclerosis and inflammation in an aneurysmal wall confirmed by autopsy. Origin as well as management of fusiform cerebral aneurysms are unclear. Antiplatelet agents and anticoagulation are recommended by some for stroke prophylaxis in patients with unruptured fusiform cerebral aneurysms. Our case shows that caution should be exercised in prescribing anticoagulants or even antiplatelet agents to a patient with fusiform aneurysm of cerebral arteries due to a possibility of rupture of an aneurysm. Randomized prospective study may be necessary to clarify this issue.

Severe brainstem compression by an unruptured giant vertebral aneurysm--an autopsy case

We describe an autopsy case of sudden unexpected death due to severe brainstem compression by an unruptured giant vertebral aneurysm. A 71-year-old male was found dead in his bedroom. The forensic autopsy revealed no severe trauma leading to his death. On internal examination, a giant intracranial aneurysm (3.4 x 2.6 x 2.7 cm) was observed on the trunk of the right vertebral artery. The aneurysm compressed the right side of the lower one-third of the pons and adjacent medulla oblongata. On sectioning, almost all of the aneurysm lumen was filled with a firm, clearly laminated organized thrombus. There was no evidence of subarachnoid hemorrhage. Histopathological analyses revealed congestion and hypoxic tissue changes in all organs examined. In microscopic sections of the giant vertebral aneurysm, thick fibrotic walls, intimal hyperplasia and organized thrombi in the lumen were found. Lots of intrathrombotic clefts with fresh erythrocytes were also observed. Moreover, Elastica van Gieson staining revealed fragmentation and disruption of the intimal elastic lamina in the aneurysmal wall. Collectively, we considered that some triggers in his daily life, including head rotation, might have caused the rapid onset of respiratory disturbance due to severe brainstem compression by a giant vertebral aneurysm.

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.

Trunkal intracranial aneurysms: dissecting and fusiform aneurysms

Aneurysms arising along the arterial trunk are uncommon and not well-characterized lesions in contrast to saccular aneurysms. According to pathological studies, most of spontaneous trunkal aneurysms are related to dissecting phenomena. On the basis of clinical presentation, dissecting aneurysms can be separated into acute or chronic lesions. Understanding of the underlying pathological mechanisms associated with these aneurysms is useful for planning appropriate treatment. This article reviews the etiopathogenesis, the angiographic aspects, and the endovascular treatment of dissecting aneurysms. Fusiform aneurysms and aneurysms in atherosclerotic disease also are discussed briefly.

Intracranial Aneurysms: an Overview

The outcome of intracranial aneurysms remains disastrous despite progress in diagnosis, management, care, and follow-up. This article discusses the pathology, the etiologies, the epidemiology and the classifications of intracranial aneurysms.

A theoretical model of enlarging intracranial fusiform aneurysms

The mechanisms by which intracranial aneurysms develop, enlarge, and rupture are unknown, and it remains difficult to collect the longitudinal patient-based information needed to improve our understanding. We submit, therefore, that mathematical models hold promise by allowing us to propose and test competing hypotheses on potential mechanisms of aneurysmal enlargement and to compare predicted outcomes with limited clinical information--in this way, we may begin to narrow the possible mechanisms and thereby focus experimental studies. In this paper, we present a constrained mixture model of evolving thin-walled, fusiform aneurysms and compare multiple competing hypotheses with regard to the production, removal, and alignment of the collagen that provides the structural integrity of the wall. The results show that this type of approach has the capability to infer potential means by which lesions enlarge and whether such changes are likely to produce a stable or unstable process. Such information can better direct the requisite histopathological examinations, particularly on the need to quantify collagen orientations as a function of lesion geometry.

Long-term follow-up of giant serpentine MCA aneurysm treated with EC-IC bypass and proximal occlusion

Giant serpentine aneurysms are a rare but important subset of giant aneurysms, with unique management considerations. We present long-term follow-up clinical and imaging features of a giant serpentine middle cerebral artery lesion treated with extracranial-intracranial bypass and proximal occlusion more than a decade earlier. Calcification of the obliterated aneurysm sac and durability of this management strategy are demonstrated.

Treatment of a sequential giant fusiform aneurysm of the basilar trunk

We report an exceptional case of a de novo giant fusiform aneurysm of the basilar trunk, which developed shortly after the therapeutic occlusion of the right internal carotid artery for a fusiform carotid aneurysm. It would appear to be appropriate to call this entity a sequential giant fusiform aneurysm. The patient was successfully treated with endovascular occlusion of the giant basilar trunk aneurysm following bypass surgery.

The Natural History of Radiographically Defined Vertebrobasilar Nonsaccular Intracranial Aneurysms

BACKGROUND

Vertebrobasilar nonsaccular intracranial aneurysms (VBNIA) are characterized by dilatation, elongation, and tortuosity of the vertebrobasilar system.

METHODS

The medical records and imaging of patients with vertebrobasilar fusiform aneurysms or dolichoectasia between 1989 and 2001 were reviewed. Prospective follow-up was obtained.

RESULTS

One hundred and fifty-nine patients were identified (74% male) with 719 patient years of follow-up. Presenting events included: hemorrhage (3%), ischemia (28%), and compression (22%). The remainder were incidental. The 1-, 5-, and 10-year risk of cerebral infarction (CI) due toVBNIA is 2.7, 11.3, and 15.9% respectively. The risk of recurrent CI is 6.7% per patient year. Median survival was 7.8 years and death was most commonly due to ischemia.

CONCLUSIONS

VBNIA are more common in men and typically present in the 6-7th decade. Recurrent CI is more common than hemorrhage risk.