Trunkal intracranial aneurysms: dissecting and fusiform aneurysms

Optimizing timing for quantification of intracranial aneurysm enhancement: a multi-phase contrast-enhanced vessel wall MRI study

OBJECTIVES

Aneurysm wall enhancement (AWE) on high-resolution contrast-enhanced vessel wall MRI (VWMRI) is an emerging biomarker for intracranial aneurysms (IAs) stability. Quantification methods of AWE in the literature, however, are variable. We aimed to determine the optimal post-contrast timing to quantify AWE in both saccular and fusiform IAs.

MATERIALS AND METHODS

Consecutive patients with unruptured IAs were prospectively recruited. VWMRI was acquired on 1 pre-contrast and 4 consecutive post-contrast phases (each phase was 9 min). Signal intensity values of cerebrospinal fluid (CSF) and aneurysm wall on pre- and 4 post-contrast phases were measured to determine the aneurysm wall enhancement index (WEI). AWE was also qualitatively analyzed on post-contrast images using previous grading criteria. The dynamic changes of AWE grade and WEI were analyzed for both saccular and fusiform IAs.

RESULTS

Thirty-four patients with 42 IAs (27 saccular IAs and 15 fusiform IAs) were included. The changes in AWE grade occurred in 8 (30%) saccular IAs and 6 (40%) in fusiform IAs during the 4 post-contrast phases. The WEI of fusiform IAs decreased 22.0% over time after contrast enhancement (p = 0.009), while the WEI of saccular IAs kept constant during the 4 post-contrast phases (p > 0.05).

CONCLUSIONS

When performing quantitative analysis of AWE, acquiring post-contrast VWMRI immediately after contrast injection achieves the strongest AWE for fusiform IAs. While the AWE degree is stable for 36 min after contrast injection for saccular IAs.

CLINICAL RELEVANCE STATEMENT

The standardization of imaging protocols and analysis methods for AWE will be helpful for imaging surveillance and further treatment decisions of patients with unruptured IAs.

KEY POINTS

Imaging protocols and measurements of intracranial aneurysm wall enhancement are reported heterogeneously. Aneurysm wall enhancement for fusiform intracranial aneurysms (IAs) is strongest immediately post-contrast, and stable for 36 min for saccular IAs. Future multi-center studies should investigate aneurysm wall enhancement as an emerging marker of aneurysm growth and rupture.

Successive development of ischemic malignant strokes in a patient with multiple fusiform aneurysms: A case report

BACKGROUND

Intracranial fusiform aneurysms are rare, spindle-shaped, and nonsaccular arterial dilatations that may be caused by dissection.

CASE SUMMARY

A 48-year-old man complained of wake-up onset of dysarthria and left-sided weakness. Diffusion-weighted magnetic resonance imaging of the brain revealed an infarction in the territories of the right middle and posterior cerebral arteries. Computed tomography angiography showed fusiform aneurysms in the right vertebral artery and bilateral petrous segments of the internal carotid arteries (ICAs). Despite conservative management, malignant ischemic stroke recurred in the contralateral ICA territory within a day of the onset of the index stroke.

CONCLUSION

We report a rare case of successive malignant strokes in a patient with multiple fusiform aneurysms. Herein, we emphasize that clinicians should consider aggressive treatment for patients with ischemic stroke and multiple fusiform aneurysms.

Treatment of fusiform aneurysms with a pipeline embolization device: a multicenter cohort study

BACKGROUND

Intracranial fusiform aneurysms are less common than saccular aneurysms, but are associated with higher mortality and morbidity. We conducted this study to determine the safety and efficacy of the pipeline embolization device (PED) to treat intracranial fusiform aneurysms.

METHODS

This was a multicenter, retrospective, and observational study. Data for this study came from the PLUS study conducted from 2014 to 2019 across 14 centers in China. Univariate and multivariable logistic regression analyses were performed to evaluate predictors of the occlusion rate and complication.

RESULTS

A total of 1171 consecutive patients with 1322 intracranial aneurysms participated in this study. Among the participants, 104 patients with 109 fusiform aneurysms were eligible for this analysis (mean age 49 years, 36.5% women, aneurysm mean size 14.7 mm, 55% in the posterior circulation, and 6% in the basilar artery). Mean follow-up time was 9.0 months (range 3-36 months). The last DSA angiographic follow-up was available for 85 patients, and 58 aneurysms (68.2%) were completely occluded. The overall complication rate and mortality were 17.3% and 2.8%, respectively. Multivariate analysis demonstrated that age (OR=1.007, p=0.037) and cerebral atherosclerosis (OR=1.441, p=0.002) were associated with incomplete occlusion of fusiform aneurysms after PED treatment.

CONCLUSION

PEDs may be an effective treatment for intracranial fusiform aneurysms, with a favorable occlusion rate. However, because these treatments have a relatively high rate of complications, PED treatment for fusiform aneurysms should be carefully and strictly controlled. Our analysis showed that PEDs with adjunctive coiling did not significantly improve the occlusion rate of fusiform aneurysms.

Aneurysm wall enhancement, atherosclerotic proteins, and aneurysm size may be related in unruptured intracranial fusiform aneurysms

OBJECTIVE

This cross-sectional study aimed to investigate the associations between aneurysm wall enhancement (AWE), atherosclerotic protein levels, and aneurysm size in unruptured intracranial fusiform aneurysms (IFAs).

METHODS

Patients with IFAs underwent high-resolution magnetic resonance imaging (HR-MRI) and atherosclerotic protein examinations from May 2015 to December 2021 were collected. A CR_stalk (signal intensity [SI] of IFA wall/SI of pituitary stalk) > 0.60 was considered to indicate AWE. Atherosclerotic protein data was obtained from the peripheral blood. Aneurysmal characteristics included the maximal diameter of the cross-section (D_max), location, type of IFA, presence of mural thrombus, and mural clots. Statistical analyses were performed with univariate analysis, logistic regression analysis, and Spearman's correlation coefficient.

RESULTS

Seventy-one IFAs from 71 patients were included in the study. Multivariate analysis revealed statin use (OR = 0.189, p = 0.026) and apolipoprotein B (Apo-B) level (OR = 6.019, p = 0.026) were the independent predictors of AWE in IFAs. In addition, statin use (OR = 0.813, p = 0.036) and Apo-B level (OR = 1.610, p = 0.003) were also the independent predictors of CR_stalk. Additionally, we found that CR_stalk and AWE were significantly positively associated with D_max (r_s = 0.409 and 0.349, respectively; p < 0.001 and p = 0.003, respectively).

CONCLUSIONS

There may be correlations between AWE, atherosclerotic protein levels, and aneurysm size in patients with IFAs. Apo-B and statin use were independent predictors of AWE in IFAs, which have the potential to be new therapeutic targets for IFAs.

KEY POINTS

• There may be correlations between aneurysm wall enhancement, atherosclerotic protein levels in the peripheral blood, and aneurysm size in patients with intracranial fusiform aneurysms. • Apolipoprotein B and statin use were independent predictors of aneurysm wall enhancement in intracranial fusiform aneurysms.

The hemodynamic effect of eccentricity in visceral branched aneurysms with multilayer stents

It is preliminarily acknowledged that multilayer stent (MS) is a promising alternative technology in the treatment of visceral branched aneurysms, but hemodynamic consequences of eccentricity in such aneurysms with MS are less examined. In this work, we performed a time-dependent simulation of branched aneurysms of various eccentricities with different stent layers, and thrombosis-related parameters, such as time-averaged wall shear stress (TAWSS), oscillating shear index (OSI), and relative residence time (RRT), were also analyzed. Our results revealed that MS can generally restore laminar flow inside the stent, and allow proper perfusion to vital organs while also fostering a relatively secluded hemodynamic environment for thrombosis formation. Particularly, a flow in the aneurysm sac communicating between the main artery and side branch forms at early systole. However, MS fails to completely eliminate detrimental flow impingement after peak systole, which may hinder aneurysm recovery, especially in the cases of eccentric aneurysms. Therefore, saccular aneurysms should be treated with more caution than fusiform aneurysms. And further therapeutic attempts to keep both perfusion in the proximal region of the aneurysm and isolation in the distal region of the aneurysm should be considered.

Quantification of aneurysm wall enhancement in intracranial fusiform aneurysms and related predictors based on high-resolution magnetic resonance imaging: a validation study

Background:

Aneurysm wall enhancement (AWE) in high-resolution magnetic resonance imaging (HR-MRI) has emerged as a new imaging biomarker of intracranial aneurysm instability.

Objective:

To determine a standard method of AWE quantification for predicting fusiform intracranial aneurysms (FIAs) stability by comparing the sensitivity of each parameter in identifying symptomatic FIAs. The predictors of AWE and FIA types were also identified.

Methods:

We retrospectively analyzed consecutive fusiform aneurysm patients who underwent HR-MRI from two centers. The aneurysm-to-pituitary stalk contrast ratio (CR_stalk), aneurysm enhancement ratio, and aneurysm enhancement index were extracted, and their sensitivities in discriminating aneurysm symptoms were compared using the receiver-operating characteristic curve. Morphological parameters of fusiform aneurysm were extracted based on 3D vessel model. Uni- and multivariate analyses of related predictors for AWE, CR_stalk, and FIA types were performed, respectively.

Results:

Overall, 117 patients (mean age, 53.3 ± 11.7 years; male, 75.2%) with 117 FIAs underwent HR-MRI were included. CR_stalk with the maximum signal intensity (CR_stalk-max) had the highest sensitivity in identifying symptomatic FIAs with an area under the curve value (0.697) and a cut-off value of 0.90. The independent predictors of AWE were aneurysm symptoms [(odds ratio) OR = 3.754, p = 0.003], aspirin use (OR = 0.248, p = 0.037), and the maximum diameter of the cross-section (OR = 1.171, p = 0.043). The independent predictors of CR_stalk-max were aneurysm symptoms (OR = 1.289, p = 0.003) and posterior circulation aneurysm (OR = 1.314, p = 0.001). Transitional-type showed higher rates of hypertension and mural thrombus over both dolichoectatic- and fusiform-type FIAs.

Conclusion:

CR_stalk-max may be the most reliable parameter to quantify AWE to distinguish symptomatic FIAs. It also has the potential to identify unstable FIAs. Several factors contribute to the complex pathophysiology of FIAs and need further validation in a larger cohort.

Endovascular Parent Artery Occlusion for Intracranial Aneurysms is a Viable, Cost-Effective Alternative: An Institutional Experience from Northeast India

Purpose.

Endovascular parent artery occlusion (PAO) may be an alternative approach for complex intracranial aneurysm with potentially life-threatening complications. Moreover, the long-term follow-up of the PAO for an intracranial aneurysm is reported sparingly, limited to the case series. It is therefore important to carry out more research on long-term follow-up of the implication of PAO of intracranial aneurysm. The aim of the study was to analyses our experience of PAO for intracranial aneurysms with emphasis on long-term follow-up.

Materials and Methods.

The data of patients treated with PAO for intracranial aneurysms were reviewed. The outcome was evaluated based on aneurysmal occlusion on immediate angiography, follow-up magnetic resonance angiography (MRA), and complications. The modified Rankin score (mRS) was used to evaluate the functional outcome during the last follow-up. The mean, range, and standard deviation were reported for other variables – the patient’s age, number, and percentage.

Results.

Endovascular treatment was performed in 178 patients including PAO in 18 patients. Of these 18 (eighteen) patients, there were 13 dissecting aneurysms, 4 mycotic aneurysms, and one traumatic aneurysm.

10 (ten) patients underwent PAO for proximal intracranial artery aneurysm and 8 (eight) patients for distal cerebral aneurysms. Complete occlusion of the aneurysm was achieved in 16patients (88.89%) and retrograde filling of the aneurysm was seen in 2 (11.11%) patients. One patient had intraprocedural coil migration resulting in a major infarct with an mRS of 2. Another patient (5.56%) had recanalization of the aneurysm and presented with rupture and intracranial hemorrhage with an mRS score of 4. The mRS of the other 16 patients (88.89%) was zero.

Conclusions.

Endovascular PAO for cerebral aneurysms was highly feasible and achieved complete occlusion. The morbidity and mortality rates were at the long-term follow-up also acceptable with negligible complications.

Wall enhancement of intracranial saccular and fusiform aneurysms may differ in intensity and extension: a pilot study using 7-T high-resolution black-blood MRI

PURPOSE

To evaluate and compare wall enhancement patterns in saccular and fusiform intracranial aneurysms using high-resolution black-blood MRI at 7 T.

METHODS

Thirty-one patients with 32 unruptured intracranial aneurysms (21 saccular and 11 fusiform) underwent 7-T black-blood MRI. Aneurysm wall enhancement (AWE) was categorized as follows: no wall enhancement (NWE), focal wall enhancement (FWE), and uniform wall enhancement (UWE). The degree of enhancement was scored as follows: 0 (no enhancement), 1 (signal intensity (SI) of the aneurysm wall less than that of the pituitary infundibulum), and 2 (equal to that of the pituitary infundibulum). The chi-squared test was used to compare the AWE pattern and degree between saccular and fusiform aneurysms.

RESULTS

In saccular aneurysms, 12/21 (57%) enhanced. Of these, 9 showed FWE (5 grade 1 and 4 grade 2), and 3 showed UWE (2 grade 1 and 1 grade 2). In fusiform aneurysms, 11/11 (100%) enhanced. Of these, 1 showed FWE and 10 showed UWE. All fusiform aneurysms had grade-2 enhancement. Fusiform aneurysms had more extensive and higher SI AWE than saccular aneurysms (p < 0.01) despite having a similar size (6.9 ± 3.0 mm vs. 8.0 ± 2.9, p = 0.23). For saccular aneurysm, larger aneurysm size was correlated with higher degree of enhancement with Pearson's r = 0.64 (p = 0.002).

CONCLUSION

Intracranial fusiform aneurysms had enhancement of higher SI and that covered a more extensive area than saccular aneurysms, which might indicate differences in vessel wall pathology.

KEY POINTS

• Intracranial aneurysm wall enhancement can be reliably characterized by 7-T black-blood MRI. • AWE in intracranial fusiform aneurysms presents over a larger surface area and with greater signal intensity as compared with that in saccular aneurysms, which might indicate differences in pathology. • Stronger signal intensity of AWE correlates with the aneurysm size in saccular aneurysms.

Fusiform Superior Cerebellar Artery Aneurysm Treated with Endovascular Treatment

An aneurysm of the distal superior cerebellar artery (SCA) is a highly rare disease. Fusiform aneurysms of the distal SCA are particularly challenging to treat. Clipping, trapping with or without bypass using microsurgery or endovascular treatment (EVT) were used to treat this condition. We describe the case of fusiform distal SCA aneurysms treated successfully with endovascular coiling with a 3-month follow-up. A 39 year-old male was presented with subarachnoid hemorrhage (SAH) and a 15 mm fusiform aneurysm of the ambient segment of the left distal SCA. EVT for parent artery occlusion and packing of the aneurysm was done. Left sixth nerve palsy appeared after 1 day of EVT. The symptom completely recovered within 1 week of the post-procedural period. No neurological deficit was seen during the clinical 3-month follow-up. EVT of fusiform distal SCA aneurysms with coils is a safe and feasible option to manage this rare condition. However, the treatment options must be carefully selected depending on the neurologic condition, development of collateral circulation, and configuration of the dissection.

Fusiform superior cerebellar artery aneurysm treated with STA-SCA bypass and trapping

BACKGROUND

Fusiform aneurysms of cerebellar arteries are rare. Different surgical techniques to address these challenging lesions have been described, and their application depends on whether the goal is to maintain the flow in the parent vessel or to occlude it.

CASE DESCRIPTION

The authors reported a case of a fusiform aneurysm located in the lateral pontomesencephalic segment of the superior cerebellar artery (SCA) in a 32-year-old man who presented with subarachnoid hemorrhage. The patient was subjected to aneurysm trapping followed by a bypass between the superficial temporal artery (STA) and SCA and had an uneventful recovery.

CONCLUSIONS

Although only a few cases of fusiform aneurysms in the supracerebellar artery have been reported in the literature, the treatment strategies adopted were diverse. In selected cases of patients in good neurological condition with ruptured fusiform aneurysms at the proximal segments of SCA and who have poor evidence of collateral supply, the possibility of a STA-SCA bypass with aneurysm trapping must be considered. A review of the current treatment modalities of this pathology is also presented.

Intramural hematoma detection by susceptibility-weighted imaging in intracranial vertebral artery dissection

BACKGROUND

The radiologic diagnosis of vertebral artery dissection (VAD) depends on characteristic intraluminal findings on angiography and intramural hematoma or a double-lumen sign on high-resolution vessel wall imaging. We aimed to evaluate the accuracy of intramural hematoma sign on susceptibility-weighted imaging (SWI) in VAD.

METHODS

We retrospectively analyzed SWI, phase map images and brain computed tomography (CT) of the consecutive patients who suffered an ischemic stroke in the vertebral artery territory from August 2010 to July 2012. We divided the patients into 2 groups: the VAD group and the nondissection group. VAD was diagnosed by conventional catheter angiographic findings (aneurysmal dilatation, pearl-and-string or tapered steno-occlusion) and pathognomonic findings such as intramural hematoma or a double-lumen sign on the source images of TOF-MRA, high-resolution T1-weighted MRI or high-resolution T2-weighted MRI. Intramural hematoma sign was considered positive if the patient had an eccentric or concentric hypointense signal lesion in the vertebral artery on SWI, a corresponding hyperintense signal on phase map and no evidence of calcification on the brain CT, suggesting blood products other than calcification. Two experienced neuroradiologists blinded to clinical information and angiographic findings were asked to judge for the presence of intramural hematoma sign on SWI. The accuracy of intramural hematoma sign on SWI was evaluated. Phase value, demographic and clinical data were compared between the VAD and the nondissection groups.

RESULTS

Thirty-nine patients were included: 10 in the VAD group and 29 in the non-dissection group. Among the VAD group cases, intramural hematoma sign on SWI was positive in 9 of the 10 VAD cases and in 1 out of the 29 cases in the nondissection group. The intramural hematoma sign on SWI was significantly associated with VAD (p < 0.001), and showed sensitivity of 90% and specificity of 96.6%. Mean phase values of intramural hematomas (n = 9) were all positive and those of calcified lesions (n = 13) were all negative (0.45 radian vs. -0.42 radian, p < 0.001).

CONCLUSIONS

The intramural hematoma sign on SWI was significantly associated with VAD and the phase map values were higher in intramural hematomas when compared with atherosclerotic calcifications.

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.

Management of anterior inferior cerebellar artery aneurysms: endovascular treatment and clinical outcome

BACKGROUND AND PURPOSE

AICA aneurysms are rare and a challenge to treat surgically. We present our experience of the angiographic results and the clinical outcomes for 9 AICA aneurysms treated by EVT.

MATERIALS AND METHODS

Between 1997 and 2009, EVT was attempted for 9 AICA aneurysms. Six patients presented with SAH, and 3 aneurysms were found incidentally. The location of the aneurysms was the proximal AICA in 7 and the distal AICA in 2. Five aneurysms originated from an AICA-PICA variant. Clinical outcomes and procedural complications were evaluated, and angiography was performed 6, 12, and 24 months after embolization to confirm recanalization of the coiled aneurysm.

RESULTS

EVT was technically successful in 7 patients (78%). Surgical trapping was performed in 1 patient after failure of EVT, and another aneurysm occluded spontaneously, along with the parent artery during EVT. In 7 patients, the AICAs had good patency on postoperative angiography. Stent-assisted coiling was performed in 3 patients. Follow-up angiographies were performed in 7 patients and showed no evidence of recanalization or progressive occlusion with further thrombosis except in 1 patient. There was no evidence of aneurysm rupture during the follow-up period, and 8 patients were able to perform all usual activities (mRS score, 0-1).

CONCLUSIONS

EVT may provide a feasible and safe option as an alternative, though a microsurgical option is initially considered for the management of AICA aneurysms. Further follow-up and more experience are also necessary.

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.

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.

A combined approach to treatment of the dissecting middle cerebral artery fusiform aneurysm. A case report

SUMMARY

A fusiform aneurysm in the terminal M1 middle cerebral artery (MCA) segment was treated by a construction of a high-flow arterial extracranial-intracranial (EC-IC) bypass. Due to severe bypass vasospasms, local vasodilating agents together with percutaneous angioplasty and stent implantation were applied, but failed due to subsequent bypass occlusion. To remedy this complication a new bypass was created from a segment of the saphenous vein, followed by MCA aneurysm embolization and parent artery occlusion. One year after the surgery, the venous bypass remains patent and the aneurysm occluded, with the patient fully active, without any neurological sequelae.

Intraventricular hemorrhage caused by peripheral anterior choroidal artery aneurysm rupture. A case report

Intraventricular hemorrhage is a severe ictal event secondary to several pathological conditions (anticoagulation therapies, hypertension, post-surgical, traumatic, neoplastic, vascular malformations), leading to blockage of CSF flow and possible hydrocephalus, often justifying surgical intervention. We describe an uncommon source of intraventricular hemorrhage in a 54-year-old woman caused by a peripheral anterior choroidal artery aneurysm rupture.

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.

Idiopathic aneurysms of distal cerebellar arteries: endovascular treatment after rupture

INTRODUCTION

Idiopathic ruptured aneurysms of distal cerebellar arteries (DCAAs) are rare, and their endovascular therapy (EVT) has as yet not been extensively reported. They are usually assumed to result from local arterial wall disruption rather than infection, unlike distal supratentorial artery aneurysms. This study was performed to audit their frequency, potential aetiology and results of EVT.

PATIENTS AND METHODS

Using strict inclusion criteria and a database of 1715 EVT patients, we identified ten idiopathic ruptured DCAAs (0.6%) over a 13-year period (1993-2006). The series comprised six males and four females with mean age of 64 years and solitary aneurysms located on posterior inferior cerebellar artery (five patients), anterior inferior cerebellar artery (three patients) and superior cerebellar artery (two patients). Nine aneurysms were fusiform and were treated by endovascular parent artery occlusion, and one was saccular and treated by endosaccular packing. Endovascular therapy was performed with coils in seven cases, n-butyl-2-cyanoacrylate (NBCA) in two cases and with both in one case.

RESULTS

Primary EVT was successful in eight patients. One patient died following a procedure-related re-bleeding and one patient required re-treatment after failed endosaccular packing. Nine patients made good or excellent clinical recoveries (modified Rankin Scale 2 or less). Focal cerebellar infarctions were seen on computed tomography images after EVT in three patients, only one of whom was symptomatic with transient dysmetria, which resolved completely during follow up. No aneurysm recanalisation was detected on late follow-up imaging up to 24 months.

CONCLUSION

Ruptured DCAAs are rare. The majority are fusiform in shape and their aetiology remains uncertain. Endovascular treatment is feasible and effective. It usually requires parent artery occlusion.