Endovascular treatment of small intracranial aneurysms: three alternatives to coil occlusion

Pipeline Embolization Device for Treatment of Extracranial Internal Carotid Artery Pseudoaneurysms: A Multicenter Evaluation of Safety and Efficacy

BACKGROUND

There is a paucity of literature regarding treatment options for extracranial pseudoaneurysms of the internal carotid artery (ICA). To date, Pipeline Embolization Device (PED; Medtronic Inc) use for the treatment of extracranial pseudoaneurysms of the ICA has only been reported from single-center case series.

OBJECTIVE

To evaluate the safety and efficacy of PED for the treatment of extracranial ICA pseudoaneurysms.

METHODS

This is a multicenter retrospective study involving 6 high-volume tertiary academic institutions in the United States. We analyzed patients with extracranial ICA pseudoaneurysms treated with PED between January 1, 2011, and January 1, 2019. Clinical assessment was performed pre- and postintervention using the modified Rankin Scale (mRS) and National Institution of Health Stroke Scale (NIHSS) at a minimum of 4-mo follow-up.

RESULTS

A total of 28 pseudoaneurysms with a mean diameter of 17.7 mm (range: 4.1-52.5 mm) were treated with PED in 24 patients at 6 participating centers. The mean age was 52.1 yr (17-73) ± 14.3 with 14 females and 10 males. At a mean of 21-mo (range 4-66 mo) follow-up, complete occlusion was achieved in 89% (n = 25/28), with near-complete occlusion (>90% occlusion) in the remainder. There were no periprocedural complications. Postprocedure NIHSS was 0 in 88% (n = 21/24) and 1 in 12% (n = 3/24) of patients, and mRS was 0 in 83% (n = 20/24) and 1 in 17% (n = 4/24) of patients.

CONCLUSION

The treatment of extracranial ICA pseudoaneurysms with PED is safe and effective in selected patients. Randomized controlled trials and prospective cohort studies are needed to establish the role of flow diversion for ICA pseudoaneurysms.

Endovascular occlusion of pial arteriovenous macrofistulae, using pCANvas1 and adenosine-induced asystole to control nBCA injection

Background In large-caliber pial macrofistulae (pMF), the combination of high blood flow velocity and large efferent artery diameter makes control over the endovascular vessel occlusion difficult and may result in the inadvertent venous passage of occlusive devices or embolic agents. Case descriptions Patient 1: A 27-year-old man presented with headache and ataxia. An infratentorial pMF supplied by both superior cerebellar arteries with venous ectasia was found. The first treatment attempt using balloons and coils failed since the position of either device could not be controlled because of a distal diameter of the feeding artery of 8 mm. In a second session a pCANvas1 (phenox) was deployed at the level of the arteriovenous connection and adenosine-induced asystole allowed the controlled injection of nBCA/Lipiodol with partial occlusion of the pMF. A remaining arteriovenous shunt was occluded under asystole in a third session. The procedures were well tolerated, the patient returned to normal and DSA confirmed the occlusion of the fistula. Patient 2: A 13-year-old boy with hereditary hemorrhagic teleangiectasia presented with an intracerebral hemorrhage from an aneurysm of the left MCA. Twelve weeks after the aneurysm treatment a feeding MCA branch (diameter 4.5 mm) of a right frontal pMF was catheterized. The macrofistula was occluded by deployment of a pCANvas1, followed by the injection of nBCAl/Lipiodol under adenosine-induced asystole. Conclusion pCANvas1 and adenosine-induced asystole allow a controlled injection of nBCA/Lipiodol for the endovascular occlusion of high-flow pMF without venous passage of the embolic agent.

Surgical management of ruptured small cerebral aneurysm: Outcome and surgical notes

Background:

Management of small aneurysms often poses a therapeutic dilemma and surgical treatment or coiling can be considered as therapeutic choices. In the present study, we reviewed our series of ruptured small cerebral aneurysm treated surgically.

Methods:

A total of 53 consecutive patients with ruptured small aneurysm were surgically treated between January 2008 and July 2014. Data were retrospectively collected. Procedure-related death and complications were systematically reviewed. Clinical outcomes were assessed using the Modified Ranking Scale. Neuroradiological follow-up was performed to assess aneurysmal occlusion and recanalization rate.

Results:

The mean aneurysm size was 2 mm ± 0.8 mm. All the patients were operated and the aneurysm clipped. Clinical outcomes were as expected on the basis of the presenting Hunt and Hess grade. Overall, major and minor neurological deficit related to clipping were 5.2% and 2.2%, respectively. At the time of discharge, 84.9% of the patients presented with a favorable outcome, while 15.1% had poor clinical outcome. Aneurysm occlusion was achieved in all the cases. Neither recanalization nor re-aneurysmal rupture was observed in the clinical follow-up.

Conclusion:

Aneurysms, 3 mm in diameter or smaller, represent a therapeutic challenge. Given the proven role of microsurgery in small aneurysms and the perceived challenges with endovascular therapy, surgical clipping still can be considered an effective treatment modality in this setting.

Size and anatomic location of ruptured intracranial aneurysms in patients with single and multiple aneurysms: a retrospective study from a single center

BACKGROUND AND PURPOSE

The difference in the relationship between the size of intracranial aneurysms (IAs) and their risk of rupture in patients with singe IAs versus those with multiple IAs is unclear. We sought to retrospectively analyze the size of ruptured IAs (RIAs) in patients with single and multiple IAs in order to study this relationship further.

METHODS

We retrospectively measured the size and location of RIAs in all patients who presented to our institute with an acute subarachnoid hemorrhage between 1 January 2005 and 31 December 2010. The IAs were classified by size into very small IAs or VSAs (≤3 mm), small IAs or SAs (>3 mm but ≤7 mm) and others (>7 mm).

RESULTS

379 patients (281 with a single IA, Group 1 and 98 with multiple IAs, Group 2) with 419 treated RIAs were included in the study. VSAs and SAs constituted the majority of RIAs in both groups (33.5% and 45.2% in Group 1 and 24.6% and 50.7% in Group 2) and the mean size of the RIAs was not different between the two groups. VSAs constituted almost two-thirds of all RIAs in certain locations whereas IAs > 7 mm in size did not constitute more than a third of the RIAs at any of the arterial locations.

CONCLUSIONS

The high incidence of VSAs, particularly in certain locations in both patient subgroups, suggests that current diagnostic, prognostic and therapeutic options in the management of IAs should be more tailored towards the management of these difficult-to-treat lesions.

Strategies and outcomes for coiling very small aneurysms

OBJECTIVE

Coiling of aneurysms 3 mm in diameter or less has been associated with a relatively high rate of complications, including iatrogenic rupture. The present study aimed to determine the clinical outcome of our technique for coiling small aneurysms.

METHODS

A retrospective chart review was performed of prospectively collected data for all patients who had endovascular coiling of an aneurysm 3 mm in diameter or less between 2003 and 2008. Follow-up imaging with magnetic resonance or catheter angiography was performed at varying intervals after coiling, ranging from 1 to 6 years after the procedure. Angiographic results were assessed using the Raymond-Roy (RR) grading system. Clinical outcomes during the same period were measured using the modified Rankin Scale.

RESULTS

Between March 2003 and April 2008, 20 patients underwent coil embolization of an aneurysm 3 mm or smaller--17 ruptured and 3 unruptured. After the procedure, 10 aneurysms were completely occluded (RR 1), 7 had residual filling of the neck (RR 2), and 3 had residual filling of the fundus (RR 3). There were no iatrogenic ruptures. Stent assistance was used in three cases. Balloon assistance was not used. Two patients were retreated, but no aneurysm reruptured. Clinical outcomes were as expected on the basis of the presenting Hunt & Hess grade. One patient with a ruptured aneurysm died from complications related to severe vasospasm.

CONCLUSION

Aneurysms 3 mm in diameter or smaller can be coiled safely with the use of both bare platinum and hydrogel-coated coils. In most cases, coiling of small aneurysms can be performed without the use of adjunctive devices such as balloons or stents.

Coiling of ruptured tiny cerebral aneurysms, feasibility, safety, and durability at midterm follow-up, and individual experience

BACKGROUND AND PURPOSE

The tiny size of cerebral aneurysms represents one of the challenging facets for endovascular treatment, with a high risk for intraoperative rupture (IOR). We report on the treatment of tiny ruptured saccular cerebral aneurysms by coil embolization. All cases were that of £ 2-3 mm aneurysms with at least one of the dimensions < 2 mm.

MATERIALS AND METHODS

Between April 2008 and December 2010, we performed a retrospective analysis of nine consecutive cases of tiny aneurysms treated by coil embolization in our institution.

RESULTS

Coil embolization was successfully performed in nine cases, whereas in one case, intraoperative rupture (IOR) of the fundus was encountered before complete obliteration of the aneurysm expected to be achieved with two coils. Complete occlusion (in n = 7 aneurysms) or near-complete immediate occlusion (in n = 2 aneurysms) was achieved. A total of 18 coils was used for coiling of the nine aneurysms, wherein five aneurysms were coiled with two coils each, two aneurysms with three coils each, and two aneurysms with only one coil each to achieve accepted results. Balloon assistance was used in three cases. Although a minimal coil projection in the parent vessel was seen in three cases, no untoward clinical complications were seen. At mean follow-up (6.7 months, interquartile range (IQR) 3-12 months), digital subtraction angiography (DSA) and magnetic resonance angiography (MRA) in nine patients demonstrated persistent complete occlusion in six of the aneurysms; one aneurysm showed marked filling of the fundus, and two showed neck remnant but did not need retreatment. All patients with available follow-up were independent in day-to-day activities with a modified Rankin score (mRS) of 0 or 1.

CONCLUSIONS

Coil embolization of tiny ruptured cerebral aneurysms is feasible. Careful consideration of the technical issues in treatment of such aneurysms is essential to achieve technical success while avoiding complications.

[Assisted techniques for the endovascular treatment of complex or atypical cerebral aneurysms]

In the last ten years, the endovascular approach to the management of cerebral aneurysms has gone from being an alternative to surgery to being the first-choice technique in the vast majority of cases. The continuous development of new assisted techniques and of new materials for embolization have multiplied its therapeutic possibilities, so that safe and efficacious endovascular treatment is now possible for aneurysms that would have required surgery only a few years ago. These continuous technological advances require the professionals that treat patients with cerebral aneurysms to achieve a high degree of specialization and to keep up to date through continuous training. In this article, we review some of the most widely used assisted techniques in the endovascular treatment of cerebral aneurysms, discussing their main indications, their advantages over conventional embolization techniques, and their possible limitations.

Endovascular treatment of very small intracranial aneurysms

The endovascular treatment of intracranial aneurysms 3 mm or less is considered controversial. The purpose of this study is to report angiographic and clinical results following coiling of such aneurysms and compare them to those of larger aneurysms (> 3 mm).Between November 1999 and November 2009 endovascular treatment was attempted in 956 consecutive intracranial aneurysms. Of 956 aneurysms, 111 aneurysms were very small aneurysms with a maximal diameter of 3 mm or less. We conducted a retrospective analysis of angiographic and clinical outcome following coiling of very small aneurysms and subsequently comparing it to the results of larger aneurysms.Coiling initially failed in eight aneurysms. In the remaining 103 aneurysms endovascular treatment was accomplished and immediate angiographic results showed complete aneurysm occlusion in 43 aneurysms, nearly complete aneurysm occlusion in 54 aneurysms and less than 90% aneurysm occlusion in six aneurysms. Complications occurred in the treatment of 15 aneurysms, including eight procedural ruptures, six thromboembolic events and one case of early hemorrhage. Compared with larger aneurysms, treatment of very small aneurysms was associated with a higher rate of procedural ruptures (7.2% versus 4.4%) and procedural mortality (4.7% versus 2.7%) but a lower procedural morbidity (1.9% versus 4.0%). However none of these differences reached statistical significance (p = 0.186, p= 0.388, respectively). The retreatment rate was higher for the larger aneurysms (8.2% and 6.3%), but this was not significant either (p= 0. 496). At nine-month follow-up significantly more small aneurysms were found to have a stable occlusion grade compared to large aneurysms.Endovascular treatment of very small aneurysms is feasible with a lower retreatment rate compared to large aneurysms (> 3 mm). However the data also suggest that endovascular treatment of very small aneurysms might be associated with an increased risk of procedural ruptures and mortality. At nine-month follow-up results indicate significantly less compaction in the very small aneurysms.

Pipeline embolization device (PED) for neurovascular reconstruction: initial experience in the treatment of 101 intracranial aneurysms and dissections

Introduction

The purpose of this study was to evaluate the safety and efficacy of the recently available flow diverter “pipeline embolization device” (PED) for the treatment of intracranial aneurysms and dissections.

Methods

Eighty-eight consecutive patients underwent an endovascular treatment of 101 intracranial aneurysms or dissections using the PED between September 2009 and January 2011. The targeted vessels include 79 (78%) in the anterior circulation and 22 (22%) in the posterior circulation. We treated 96 aneurysms and 5 vessel dissections. Multiple devices were implanted in 67 lesions (66%).

Results

One technical failure of the procedure was encountered. Immediate exclusion of the target lesion was not observed. Angiographic follow-up examinations were carried out in 80 patients (91%) with 90 lesions and revealed complete cure of the target lesion(s) in 47 (52%), morphological improvement in 32 lesions (36%), and no improvement in 11 lesions (12%). Six major complications were encountered: one fatal aneurysm rupture, one acute and one delayed PED thrombosis, and three hemorrhages in the dependent brain parenchyma.

Conclusion

Our experience reveals that the PED procedure is technically straightforward for the treatment of selected wide-necked saccular aneurysms, fusiform aneurysms, remnants of aneurysms, aneurysms with a high likelihood of failure with conventional endovascular techniques, and dissected vessels. While vessel reconstruction, performed after dissection, is achieved within days, remodeling of aneurysmal dilatations may take several months. Dual platelet inhibition is obligatory. Parenchymal bleeding into brain areas dependent on the target vessel is uncommon.

Endovascular treatment of ruptured tiny intracranial aneurysms

Endovascular treatment of ruptured tiny intracranial aneurysms (RTIA) is technically challenging. We retrospectively collected and analyzed the clinical data of 51 patients with RTIA who underwent attempted endovascular treatment at our institution between November 2000 and April 2009. Forty-nine patients were successfully treated by coiling alone (29 patients), stent-assisted coiling (11 patients) or stent placement alone (nine patients). Procedural complications occurred in five patients. One patient died from a severe initial hemorrhage and poor clinical condition. At the time of discharge, 44 patients (89.8%) had recovered in good condition (Glasgow Outcome Scale [GOS] score 5), two were moderately disabled (GOS score 4) and two were severely disabled (GOS score 3). Angiographic follow-up (mean follow-up time=14 months) was available for 33 patients, and two were re-treated. None of the 46 patients who were clinically followed up (mean=54.2 months) experienced re-bleeding. Our results suggest that RTIA is not uncommon and can be safely treated endovascularly.

Intraventricular hemorrhage secondary to intranidal aneurysm rupture-successful management by arteriovenous malformation embolization followed by intraventricular tissue plasminogen activator: case report

BACKGROUND AND IMPORTANCE

Intraventricular hemorrhage related to arteriovenous malformation (AVM) rupture is associated with significant morbidity and mortality. Intraventricular tissue plasminogen activator (tPA) has been used to treat spontaneous intraventricular hemorrhage. We demonstrate the successful application of endovascular occlusion to seal the rupture site of an AVM followed by intraventricular tPA.

CLINICAL PRESENTATION

A 32-year-old woman presented with a right frontoparietal parasagittal AVM abutting the motor cortex. The AVM was diagnosed when the patient was 13 years old, and she initially underwent conservative management. At the age of 30, the patient suffered an intracranial hemorrhage, leaving her with left hemiparesis. After rehabilitation, the patient regained ambulation; however, she remained spastic and hyperreflexic on the left side. Two years after her major hemorrhage, she presented for elective treatment of her AVM. The patient was advised to undergo staged embolization before surgical resection of her AVM. The initial embolization was uneventful. A second embolization was complicated by intraventricular hemorrhage and coma. The patient was treated with placement of an external ventricular drain followed by embolization of intranidal aneurysm. After embolization of the intranidal aneurysm the ruptured, the patient was treated with intraventricular tPA. The patient had rapid clearance of the intraventricular hemorrhage and significant improvement in her neurological examination, following commands 24 hours later and returning almost to baseline.

CONCLUSION

This case demonstrates the feasibility of treating AVM-related intraventricular hemorrhage with tPA if the rupture source can be confidently sealed interventionally. This strategy can be lifesaving but needs further study to ensure its safety.

Endovascular embolization of very small cerebral aneurysms

BACKGROUND

Very small cerebral aneurysms are considered to be one of the challenges for endovascular treatment, with difficulty for catheterization and high risk for intraoperative rupture. We report the treatment of very small (< 3-mm) cerebral aneurysms by coil embolization.

MATERIALS AND METHODS

We performed a retrospective analysis of 11 consecutive patients with very small aneurysms treated by coil embolization in our institute between February 2007 and February 2009.

RESULTS

Three-dimensional rotational angiography (3DRA) was most accurate in the detection of these aneurysms; 3DRA revealed the aneurysms in two patients in whom conventional angiography failed to demonstrate the aneurysms. The Hunt-Hess (HH) grade was grade 0 (unruptured aneurysm) in one patient and grade I in ten patients. Coil embolization was successfully performed in 11 patients. Complete (n = 8) or near complete (n = 3) immediate occlusion was obtained. One or three soft coils were used in all the patients with the shortest available length. Balloon assistance was used in one patient and stent assistance was used in seven patients. Although coil migration into the MCA was seen in one patient and intraoperative aneurismal rupture occurred in one patient, no untoward clinical complication was seen. Follow-up DSA in 11 patients demonstrated persistent occlusion (n = 9) or progressive thrombosis (n = 2) of the aneurysms. All the patients with available follow-up had a modified Rankin Score (mRS) of 0.

CONCLUSION

HH grade 0 and I very small cerebral aneurysms can be treated by endovascular coil embolization. Use of short, soft coils and balloon/stent assistance is useful.

Balloon-assisted extrasaccular coil embolization technique for the treatment of very small cerebral aneurysms

Treatment of very small ruptured cerebral aneurysms (< 2 mm) continues to present a challenge. These lesions are difficult to treat both with neurosurgical and endovascular techniques. A neurosurgical approach is still the treatment of choice for these lesions at many centers because of high rupture rates related to endovascular treatment; however, there are clinical circumstances in which the neurosurgical option cannot be offered. In their review of the literature, the authors did not find any series reporting endovascular treatment of these very small aneurysms. In the present study, the authors report their experience with the endovascular treatment of a series of 4 ruptured aneurysms smaller than 2 mm from neck to dome. They describe their technique of using a remodelling balloon to stabilize the tip of the microcatheter in the neck of the aneurysm without entering it at any time, and of inserting the coil from outside the sac to minimize the risk of intraoperative rupture, which is very high when conventional endovascular embolization is performed.

Preliminary use of the Leo stent in the endovascular treatment of wide-necked cerebral aneurysms

BACKGROUND

Currently available stents for intracranial use usually are Neuroform (Boston Scientific/Target, Fremont, CA) and Leo (Balt, Montmorency, France) stents. We present the results of our initial experience in using the Leo stent to treat patients with wide-necked cerebral aneurysms.

METHODS

Fifteen consecutive patients with wide-necked intracranial aneurysm were treated with a combined approach that consisted of delivery of a flexible self-expending neurovascular stent through a microcatheter to cover the neck of the aneurysm and subsequent filling of the aneurym with coils through the stent interstices. We assessed the clinical history, aneurysm dimensions, and technical details of the procedures, including any difficulties with stent deployment, degree of aneurysm occlusion, and complications.

RESULTS

During a 1-year period, 15 patients with 17 broad-necked aneurysms (n = 13; average neck length, 5.1 mm; average aneruysm size, 9 mm) were treated with the Leo stent. Fifteen stents were deployed successfully; two failed. Of the coiled aneurysms, complete or subtotal (more than 95%) occlusion was achieved in 11 aneurysms, and partial occlusion was achieved in 2 aneurysms. One patient had multiple stents placed. One patient had a ruptured aneurysm at the time of treatment. Technical problems included difficulty in deploying the stent (n = 2). Two periprocedural thromboembolic complications occurred. One patient had palsy after thrombolysis was attempted. The other patient made an excellent functional recovery after undergoing successful thrombolysis of a thrombosed internal carotid artery stent.

CONCLUSIONS

Preliminary data demonstrated that the Leo stent is useful device for the treatment of patients with wide-necked aneurysms. In cases with tortuous cerebral vasculature, delivery and deployment may be technically challenging. Clinically significant complications are uncommon.

Endovascular treatment of very small intracranial aneurysms

Object

Endovascular treatment of very small aneurysms poses a significant technical challenge for endovascular therapists. The authors review their experience with a series of patients who had intracranial aneurysms smaller than 3 mm in diameter.

Methods

Between 1995 and 2006, 97 very small aneurysms (defined for purposes of this study as < 3 mm in diameter) were diagnosed in 94 patients who were subsequently referred for endovascular treatment. All patients presented after subarachnoid hemorrhage, which was attributed to the very small aneurysms in 85 patients. The authors reviewed the endovascular treatment, the clinical and angiographic results of the embolization, and the complications.

Results

Five (5.2%) of the 97 endovascular procedures failed, and these patients underwent craniotomy and clip ligation. Of the 92 aneurysms successfully treated by coil embolization, 64 (69.6%) were completely occluded and 28 (30.4%) showed minor residual filling or neck remnants on the immediate postembolization angiogram. Complications occurred in 7 (7.2%) of 97 procedures during the treatment (3 thromboembolic events [3.1%] and 4 intraprocedural ruptures [4.1%]). Seventy-six patients were followed up angiographically; 4 (5.3%) of these 76 showed angiographic evidence of recanalization that required retreatment. The clinical outcomes for the 76 patients were also graded using the Glasgow Outcome Scale. In 61 (80.3%) cases the outcomes were graded 4 or 5, whereas in 15 (19.7%) they were graded 3. Seven patients (7.4%) died (GOS Grade 1), 2 due to procedure-related complications (intraoperative rupture) and 5 due to complications related to the presenting subarachnoid hemorrhage.

Conclusions

Endosaccular coil embolization of very small aneurysms is associated with relatively high rates of intraprocedural rupture, especially intraoperative rupture. With the advent of more sophisticated endovascular materials (microcatheters and microguidewires, soft and ultrasoft coils, and stents) endovascular procedures have become feasible and can lead to a good angiographic outcome.

Vertebral dissecting aneurysm treated with wingspan stent deployment and detachable coils. A technical note

We describe the first documented endovascular treatment of vertebral dissecting aneurysm using a Wingspan stent and detachable coils. A 54-year-old man presented with a nonruptured vertebral dissecting aneurysm. Because of the dissecting nature of the vertebral aneurysms, a 3x15-mm Wingspan stent was placed in the left vertebral artery. One month later, several detachable coils were introduced into the aneurysm. Six-month follow-up angiogram confirmed the obliteration. Vertebral dissecting aneurysm can be treated with Wingspan stent placement and detachable coils.

Surgical management of intracranial aneurysms in the endovascular era : review article

The advent of endovascular therapy for intracranial aneurysms and the rapid advances in that field have supplanted microsurgical treatment for many intracranial aneurysms. Applying current outcome data and other parameters, nuances of selecting the modality of treatment for intracranial aneurysms are reviewed. Patient factors, such a age, co-morbidities, vasospasm and other medical conditions, are addressed. A custom-tailored multimodality treatment paradigm for the management of ruptured and unruptured aneurysms will maximize the favorable results seen in this difficult patient population.

Endovascular Treatment of Fusiform and Wide-Necked Intracranial Aneurysms with the Neuroform 3TM and Detachable Coils

Reconstructive treatments using stents improve occlusion rate of broad-necked intracranial aueurysms and protect parent vessels. Recently, the Neuroform stent has been developed and we evaluated it use for the treatment of fusiform and broad-necked intracranial aneurysms. Seventeen fusiform and broad-necked intracranial aneurysms in 15 patients were treated electively. Eight aneurysms were located at the internal carotid artery, five in the vertebral artery, one in the basilar tip, one in the middle cerebral artery, one in the posterior cerebellar artery and one in the posterior inferior cerebellar artery. Previous attempts with the remodeling technique had been judged technically difficult in all cases, and combined stent placement across the aneurysm neck was performed with subsequent coiling of the sac. Aneurysm diameter varied from 4 to 30 mm. Sixteen aneurysms in 15 patients were treated with this procedure. There were no stent deployment failures. All aneurysms were initially stented, followed by coil placement. Complete or subtotal (>95%) occlusion was achieved in six patients, and partial occlusion (<95%) was achieved in nine. The periprocedural rate of stroke or death was 0%. Angiographic follow-up was obtained in ten patients. Neurological status remained well in all patients at a mean clinical follow-up of 6.2±3.2 months. Primary and recurrent treatment of fusiform and wide-necked intracranial aneurysms using the Neuroform stent is feasible and effective. No permanent neurological deficits were associated with stent deployment. Short-term follow-up identified intact parent arteries and stable occlusion rates in the majority of cases.

Coil embolization of very small (2 mm or smaller) berry aneurysms: feasibility and technical issues

BACKGROUND AND PURPOSE

The very small size of cerebral aneurysms is considered to be one of the limitations for endovascular treatment, with a high risk for intraoperative rupture. We report on treatment of very small saccular ruptured cerebral aneurysms by coil embolization. All the cases were of 2-mm aneurysms with at least 1 of the dimensions being less than 2 mm.

MATERIALS AND METHODS

We performed retrospective analysis of 7 consecutive cases of very small aneurysms treated by coil embolization in our institution between July 2006 and April 2008.

RESULTS

3D rotational angiography (3DRA) was found to be most accurate in the detection of these aneurysms; in 2 cases, 3DRA revealed the aneurysms after results on digital subtraction angiography (DSA) were considered to be negative. Coil embolization was successfully performed in 6 cases, whereas in 1 case, spontaneous thrombosis occurred after microcatheter placement. Complete (n = 5) or near complete (n = 2) immediate occlusion was seen. A single soft coil was used in all cases with the shortest available length. Balloon assistance was used in 3 cases. Although minimal coil projection in the parent vessel was seen in 3 cases, no untoward clinical complication was seen. Follow-up DSA and MR angiography in 4 patients demonstrated persistent occlusion (n = 3) or progressive thrombosis (n = 1) of the aneurysms. All of the patients with available follow-up are independent in day-to-day activities with a modified Rankin Score (mRS) of 0 or 1.

CONCLUSIONS

Coil embolization of very small ruptured cerebral aneurysms is feasible. Careful consideration of the technical issues in treatment of these cases is essential to achieve technical success while avoiding complications.