Long-term clinical and radiologic results of small cerebral aneurysms embolized with 1 or 2 detachable coils

Endovascular Management of Microcerebral Aneurysms with Diameter Smaller than 3 mm: Is It Feasible and Safe?

BACKGROUND

The neurosurgical management of microcerebral aneurysms with diameter smaller than 3 mm remains a great challenge as many complications can occur.

AIM

Our target was to assess the efficacy and usefulness of endovascular treatment of these lesions.

METHODS

We did a prospective and retrospective gathering of the results of endovascular treatments for a group of 16 patients with 16 microcerebral aneurysms. Four patients were treated by direct coil embolization, and 12 patients were managed by remodeling techniques.

RESULTS

Coil embolization was technically accessible in all cases. Initial complete occlusion is achieved in 12 patients. We did not face major technical complications such as aneurysmal rupture or coil migration during the endovascular management in 15 patients. Only in 1 case the second and last coil (2⁄1 mm) migrated distally and could not be retrieved. In this case clinical evidence of neurologic deterioration and weakness in left lower limb due to right anterior cerebral artery territory stroke was evidenced in the follow-up computed tomography scan. Follow-up clinical and radiological studies were available for 9 of 12 surviving patients and showed complete occlusion in 7 cases, and in 1 case aneurysm tiny recanalization was demonstrated after 1 year, which was retreated with complete occlusion, and in another case tiny aneurysm recanalization at the neck appeared after 2 years, which was left under observation.

CONCLUSIONS

Endovascular treatment is a beneficial and effective therapeutic alternative to microsurgery for microaneurysms. The long-term assessment of endovascular management for these lesions was not included in that study.

Stent-assisted coiling of very small wide-necked intracranial aneurysms: Complications, anatomical results and clinical outcomes

BACKGROUND AND OBJECTIVE

Treatment of very small (≤3mm) wide-necked intracranial aneurysms remains controversial, we investigated the efficacy and safety of stent-assisted coiling of such aneurysms.

METHODS

From September 2008 to December 2012, 112 very small wide-necked intracranial aneurysms in 108 patients were embolized with stent-assisted coiling. We assessed the initial neurological conditions, complications and anatomic results. The follow-up results were evaluated with DSA and mRS.

RESULTS

Stent deployment was successful in 104 of 108 procedures (96.3%). 11 complications (10.2%) occurred during procedures, including 5 events of aneurysm rupture, 3 events of thromboembolism. The rate of complication, rupture and thromboembolism was not statistically different between the ruptured and unruptured patients (P=0.452, P=0.369, P=1.000, respectively). The initial aneurysmal occlusion was Raymond scale (RS) 1 in 34 patients (31.5%), RS2 in 53 patients (49.1%), and RS3 in 21 patients (19.4%). 79 aneurysms were available for anatomic follow-up of 12-47 months, stable occlusion in 45 aneurysms (57.0%), progressive complete occlusion in 34 aneurysms (43.0%). 95 patients(88.0%) were available for a clinical follow-up of 12-52 months, 92 patients (96.8%) had favorable clinical outcomes (mRS ≤2), 3 patients (3.2%) had morbidity (mRS: 3-5). The morbidity was not statistically different between the ruptured and unruptured patients (P=1.000).

CONCLUSIONS

Stent-assisted coiling of very small wide-necked intracranial aneurysms may be effective and safe. Because of low risk of rupture in such aneurysms, the coiling of unruptured such aneurysms must be selective. The long-term efficacy and safety of coiling such aneurysms remains to be determined in larger prospective series.

Double microcatheter technique for coil embolization of small aneurysms with unfavorable configurations: A comparative study of the aneurysms that are ≤3 mm or >3 mm

INTRODUCTION

The endovascular coiling of small ruptured aneurysms with difficult geometries presents a significant treatment challenge. We report our initial experience and the technical details of dual microcatheter coil embolizations that were applied in these difficult lesions.

METHOD AND RESULTS

Eighty-five small aneurysms (<7 mm) that exhibited difficult configurations, such as a wide neck or an important branch vessel arising from the fundus, were successfully treated using a dual microcatheter technique. The packing attenuation, adverse events during the procedures, and angiographic occlusions from 21 very small aneurysm (≤3 mm) were recorded and compared with our coiling results of 64 small aneurysms (>3 mm, <7 mm). There were no significant differences in intraprocedural ruptures or procedure-related thromboembolisms between the two groups. At the last post-procedure clinical follow-up, a good clinical outcome (an modified Rankin Scale (mRS) of 0-2) was observed in 18 of the patients (85.7%). The recanalization rates at follow-up were significantly lower in the very small aneurysm group compared to the small aneurysm group (p < 0.05) and the mean packing density in the very small aneurysm group was significantly higher compared to the small aneurysm group (35.2% vs 24.8%, p < 0.05).

CONCLUSION

The dual technique was feasible, safe, and effective for coil embolization of aneurysms with difficult configurations and, in particular, it provided an alternative option for treating very small aneurysms.

The combinational use of dual microcatheter technique and new hypersoft helical coil for endovascular treatment of tiny intracranial aneurysm with difficult geometry

The endovascular coiling of very small ruptured aneurysms with difficult geometry presents a significant treatment challenge because of potential dangerous complications, such as intraprocedural ruptures. We report our initial experience with the use of a dual microcatheter technique, combined with new hypersoft helical coils, for the treatment of these difficult lesions. Fourteen very small aneurysms with a maximum diameter of ≤3 mm that presented difficult configurations, such as a wide neck or an important branch vessel arising from the fundus, were identified using digital subtraction angiography. These lesions were successfully treated using a dual microcatheter technique and new hypersoft helical coils. There were no intraprocedural ruptures or procedure-related thromboembolisms. Complete or near-complete occlusions were achieved in all of the lesions. A Raymond score of RS 1 was achieved in eight of the aneurysms (57.1%) and an RS 2 was achieved in six of the aneurysms (42.9%). The mean packing density was 35.5%. At the last post-procedure clinical follow-up, a good clinical outcome (a modified Rankin scale score of 0-2) was observed in 11 of the patients (91.7%). The result of angiographic follow up in 11 cases showed two recanalized aneurysms. The use of the dual microcatheter technique and new hypersoft helical coil allowed for stable coil framing and good packing in geometrically difficult tiny aneurysms and presented a low rate of adverse events related to the procedure. The technique provided an efficient strategy for treating very small aneurysms with difficult configurations and high risks.

Sole stenting technique for the treatment of uncoilable very small aneurysms in the intracranial internal carotid artery

The treatment of very small aneurysms with diameter of less than 3 mm remains a challenge for both endovascular and surgical treatment. Endovascular treatment of these lesions may be difficult and is associated with a high risk of complications because of their small size. The present study evaluated the safety, feasibility, and efficacy of the endovascular treatment using sole stenting technique for uncoilable very small aneurysms of the intracranial internal carotid artery (ICA). From August 2004 through January 2010, eight very small aneurysms of intracranial ICA in eight patients were treated with endovascular sole stenting technique. All very small aneurysms were ruptured (n = 3) or aneurysms associated with another ruptured (n = 2) and unruptured aneurysms (n = 3) in the same artery. Stents were Neuroform and balloon expandable coronary stents. Stent deployment was carried out without difficulty in all patients. Single stent deployment was done for six aneurysms, and double stents in two aneurysms. The immediate angiographic results were partial occlusion in one case and no occlusion in seven cases. One direct carotid-cavernous fistula occurred during coronary stenting without permanent neurological deficit. No neurological deterioration or hemorrhagic complication was seen during the follow-up period in seven patients. Follow-up angiography (mean 9 months) was available in six patients and revealed complete occlusion in four and no occlusion in two cases. Sole stenting technique may be a feasible and effective therapeutic alternative for uncoilable very small aneurysms. The long-term efficacy and durability of stenting for these lesions remains to be determined in a large series.

Tiny intracranial aneurysms: endovascular treatment by coil embolisation or sole stent deployment

PURPOSE

Tiny intracranial aneurysms pose a significant therapeutic challenge for interventional neuroradiologists. The authors report their preliminary results of endovascular treatment of these aneurysms.

METHODS

Between January 2002 and December 2009, 52 tiny intracranial aneurysms (defined as ≤ 3 mm in maximum diameter) in 46 patients (22 men; mean age, 57.9 years) were treated by endosaccular coil embolisation or sole stent deployment in the parent artery. Of 52 aneurysms, 29 had ruptured and 23 remained unruptured. The initial angiographic results, procedural complications, and clinical outcomes were assessed at discharge. Imaging follow-up was performed with cerebral angiography.

RESULTS

One aneurysm coiling procedure failed because of unsuccessful micro-catheterization. Forty-three aneurysms were successfully coil embolized, of which complete occlusion was obtained in 14, subtotal occlusion in 18 and incomplete occlusion in 11. The other 8 aneurysms were treated by sole stent deployment in the parent artery. Procedural complications (2 intraprocedural ruptures and 3 thromboembolic events) occurred in 5 (9.6%) of 52 aneurysms, resulting in permanent morbidity in only 1 (2.2%, 1/46) patient. No rebleeding occurred during clinical follow-up (mean duration, 46.7 months). Of the 16 coiled aneurysms that receiving repetitive angiography, 6 initially completely and 3 subtotally occluded aneurysms remained unchanged, 4 initially subtotally and 3 incompletely occluded aneurysms progressed to total occlusion. Five sole stent deployed aneurysms received angiographic follow-up (mean duration, 10.0 months), of which 3 remained unchanged, 1 became smaller and 1 progressed to total occlusion.

CONCLUSION

Endovascular treatment of tiny intracranial aneurysms is technical feasible and relatively safe. Coil embolisation seems to be effective in preventing early recanalisation, whereas sole stenting technique needs further investigation to determine its effectiveness.

Early Rebleeding of Small Anterior Communicating Artery Aneurysm with Presumed Extrusion of Coil Loop to Outside the Aneurysmal Wall during Endovascular Treatment. A Report of Two Cases

SUMMARY

Although endovascular treatment has been proved to be as effective as surgical clipping in the prevention of rebleeding of ruptured aneurysm, early rebleeding after coil embolization has seldom been reported. We experienced early rehemorrhage in two patients of ruptured small anterior communicating artery aneurysms of complete treatment with coil-embolization initially. In both cases what interested us was not early rebleeding itself but how the presumed extrusion of the first part of coil loop beyond aneurysmal wall developed. However, there was no evidence of intraprocedural rupture and moreover complete occlusion with only one or two coils was obtained. Our two patients underwent successful second treatment. We discovered the presumed extruded first part of the coil loop initially was located inside the enlarged aneurysmal sac in retreatment stage. In case of coil embolization of ruptured small anterior communicating aneurysm, the phenomenon we experienced with no evidence of intraprocedural rupture in spite of obvious extrusion of coil loop beyond the aneurysmal wall can be a sign of necessity for early follow-up study including plain radiography to track the change in the presumed extruded coil loop.

A compartmentalized volumetric system for outcome analysis of coiled cerebral aneurysms: aneurysm-coil mass-neck outcome assessment system

OBJECTIVE

Current methodologies for outcome assessment of coiled cerebral aneurysms are based on rough estimations. The aim of this study was to develop a system of quantitative analysis for objective and accurate assessment of the outcome of cerebral aneurysms treated with coil embolization.

METHODS

The quantitative analysis system is based on a concept of a perfect vessel tube and compartmentalized analysis of a coiled aneurysm. Based on the volumetric data of 3-dimensional radiographic angiography of the aneurysm and its associated parent vessel, a 2-step volume extraction method, including a global thresholding method and an augmented vessel method, is used for volume calculation. The coiled aneurysm (A) is compartmentalized into 2 volumetric components for quantitative analysis: 1) the volume of the coil mass (C), and 2) the volume of the uncoiled neck of the aneurysm (N). Changes in the volumetric data of the compartments A, C, and N at the time of follow-up provide a basis for outcome analysis. To test the clinical applicability of the system, the volumetric data for 21 consecutive cases of cerebral aneurysms in which a residual or recurrent cavity at the neck region was noted at the time of the 6-month follow-up evaluation were assessed with the aneurysm-coil mass-neck (ACN) outcome assessment system.

RESULTS

The results of the outcome analysis of the 21 cases according to the ACN system correlated well with angiographic assessment of treatment outcome.

CONCLUSION

The ACN outcome assessment system is a useful diagnostic instrument for objective and accurate assessment of the outcome of cerebral aneurysms treated with coil embolization.

Current status and future prospect of endovascular neurosurgery

Recently, due to the evolution of technology, the field of neurosurgery is receiving spotlight. In particular endovascular neurosurgery has gained a great interest along with the advancement of the modern neurosurgery. The most remarkable advances were made in embolization of the cerebral aneurysms, arteriovenous malformations and intracranial stenosis during the past 10 years. These advances will further change the role of neurosurgeons in treating cerebrovascular disease. Because interventional neuroradiologists have performed most of procedures in the past, neurosurgeons have been deprived of chances to learn endovascular procedure. This article discusses the development of technological aspect of endovascular neurosurgery in chronological order. By understanding the history and current status of the endovascular surgery, the future of neurosurgery will be promising.

Endovascular treatment of very small intracranial aneurysms

BACKGROUND

The treatment of very small cerebral aneurysms with maximal diameter less than 3 mm remains a challenge for endovascular and surgical treatment. Endovascular treatment of these lesions may be difficult and associated with high risk of complications because of their small size. Our purpose was to assess the feasibility and results of endovascular treatment of these lesions.

METHODS

We conducted a retrospective review of our experience and results of endovascular treatments for a series of 11 consecutive patients with 11 very small aneurysms. Of 11 aneurysms, 10 were acutely ruptured, and 1 was unruptured with a previous subarachnoid hemorrhage from another aneurysm. Aneurysms were located at the internal carotid artery (n = 4), the anterior communicating artery (n = 6), and the vertebral artery (n = 1). Seven patients were treated with coil embolization, and remodeling technique was used in 1 case. Three cases underwent intravascular stent implantation. Coil packing was done after in 2 of 3 aneurysms, and stent implantation alone was used in the remaining aneurysm.

RESULTS

Coil embolization and stent deployment were carried out without difficulty in all cases. Coil packing was not available after stent implantation in 1 case for unsuccessful navigation of microcatheter into the aneurysm sac. Immediate angiography demonstrated complete occlusion in 10 cases and nearly complete occlusion in 1 case with stent implantation alone. No stent thrombosis and aneurysmal rupture was encountered during treatment. With the exception of 1 patient (Hunt and Hess grade 4) who died of pneumonia 4 weeks after treatment, no clinical evidence of neurologic deterioration and hemorrhagic complication was seen during the follow-up period in the remaining 10 patients. Follow-up angiography for 3 to 12 months (mean, 5.3 months) was available in 6 (60%) of 10 surviving patients, and no aneurysm recanalization was found.

CONCLUSIONS

Endovascular treatment may be a feasible and effective therapeutic alternative for very small aneurysms. The long-term efficacy and durability of endovascular treatment for these lesions remains to be determined in a large series.