The management of residual and recurrent intracranial aneurysms after previous endovascular or surgical treatment--a report of eighteen cases

Microsurgical Treatment of Previously Coiled Giant Aneurysms: Experience with 6 Cases and Literature Review

OBJECTIVE

Surgical treatment of insufficiently embolized (coiled) or recurrent giant aneurysms has not been well established in the literature. The aim of this study is to bring up the surgical difficulties of these rare aneurysms and to offer solutions.

METHODS

A database was queried for giant aneurysms that had been previously embolized and subsequently required surgical treatment. We only found 29 aneurysms in the literature and here, we report 6 more surgical cases with patient characteristics, radiological studies, applied surgical techniques, and outcomes which were reviewed retrospectively.

RESULTS

Four females and 2 males, with a mean age of 45.6 years took part in the study. The most common aneurysm location was the middle cerebral artery. While 5 aneurysms were successfully clipped, 1 was excised and the neck was closed with micro sutures. The coils were compulsorily removed in 3 patients. Postoperative digital subtraction angiography confirmed total occlusion of the aneurysms in all cases. Overall morbidity was 16.6%. There was no mortality. No recurrence was observed in the angiographic follow-up (mean 22.6 months, range 7-47 months). The literature review also determined that 97.1% of 35 previously coiled giant aneurysms (including ours) were occluded using various surgical techniques, with 82.8% good outcome.

CONCLUSIONS

Surgical clipping is a safe and effective procedure for the treatment of insufficiently embolized or recurrent giant aneurysms after coiling. If possible, the coils should not be removed. However, if safe clipping is not possible due to the coils, the removal of the coils should not be avoided.

Intracranial post-clipping residual or recurrent aneurysms: Current status and treatment options (Review)

Following the clipping of intracranial aneurysms, post-clipping residual or recurrent aneurysms (PCRRAs) can occur. In recent years, the incidence of PCRRAs has increased due to a prolonged follow-up period and advanced imaging techniques. However, several aspects of intracranial PCRRAs remain unclear. Therefore, the present study performed an in-depth review of the literature on PCRRAs. Herein, a summary of PCRRAs that can be divided into the following two categories is presented: i) Those occurring after the incomplete clipping of an aneurysm, where the residual aneurysm regrows into a PCRRA; and ii) those occurring after the complete clipping of an aneurysm, in which a de novo aneurysm occurs at the original aneurysm site. Currently, digital subtracted angiography remains the gold standard for the imaging diagnosis of PCRRAs as it can eliminate metallic clip artifacts. Intracranial symptomatic PCRRAs should be actively treated, particularly those that have ruptured. A number of methods are currently available for the treatment of intracranial PCRRAs; these mainly include re-clipping, endovascular treatment (EVT) and bypass surgery. Currently, re-clipping remains the most effective method used to treat PCRRAs; however, it is a very difficult procedure to perform. EVT can also be used to treat intracranial PCRRAs. EVT methods include coiling (stent- or balloon-assisted) and flow-diverting stents (or coiling-assisted). Bypass surgery can be selected for difficult-to-treat, complex PCRRAs. On the whole, following appropriate treatment, the majority of intracranial PCRRAs achieve a high occlusion rate and a good prognosis.

Microsurgery of residual or recurrent complex intracranial aneurysms after coil embolization - a quest for the ultimate therapy

The long-term stability of coil embolization (CE) of complex intracranial aneurysms (CIAs) is fraught with high rates of recanalization. Surgery of precoiled CIAs, however, deviates from a common straightforward procedure, demanding sophisticated strategies. To shed light on the scope and limitations of microsurgical re-treatment, we present our experiences with precoiled CIAs. We retrospectively analysed a consecutive series of 12 patients with precoiled CIAs treated microsurgically over a 5-year period, and provide a critical juxtaposition with the literature. Five aneurysms were located in the posterior circulation, 8 were large-giant sized, 5 were calcified/thrombosed. One presented as a dissecting-fusiform aneurysm, 9 ranked among wide neck aneurysms. Eight lesions were excluded by neck clipping (5 necessitating coil extraction); 1 requiring adjunct CE. The dissecting-fusiform aneurysm was resected with reconstruction of the parent artery using a radial artery graft. Three lesions were treated with flow alteration (parent artery occlusion under bypass protection). Mean interval coiling-surgery was 4.6 years (range 0.5-12 years). Overall, 10 aneurysms were successfully excluded; 2 lesions treated with flow alteration displayed partial thrombosis, progressing over time. Outcome was good in 8 and poor in 4 patients (2 experiencing delayed neurological morbidity), and mean follow-up was 24.3 months. No mortality was encountered. Microsurgery as a last resort for precoiled CIAs can provide-in a majority of cases-a definitive therapy with good outcome. Since repeat coiling increases the complexity of later surgical treatment, we recommend for this subgroup of aneurysms a critical evaluation of CE as an option for re-treatment.

Microsurgical ligation for incompletely coiled or recurrent intracranial aneurysms: a 17-year single-center experience

Background

In this retrospective single-center study, we presented our experience in the microsurgical management of incompletely coiled or recurrent aneurysms after initial endovascular coiling.

Methods

During a 17-year period, 48 patients underwent microsurgical clipping of incompletely coiled or recurrent aneurysms after coiling (Gurian group B). The clinical data, surgical technique, and postoperative outcome were recorded and analyzed.

Results

Before coiling, 42 patients (87.5%) experienced aneurysm rupture. Most of the aneurysms (46/48, 96%) were located in the anterior circulation. After coiling, 6 patients had incompletely coiled aneurysms and 42 patients had recurrent aneurysms, with a mean time of 20.2 months from coiling to recurrence. Coil extrusion occurred in none of the incompletely coiled aneurysms and 71% (30/42) of the recurrent aneurysms. Clipping techniques are direct microsurgical clipping without coil removal in 16 patients, partial coil removal in 14 patients, and total coil removal in 18 patients. Postoperative and follow-up angiography revealed complete occlusion of the aneurysms in all patients. No patient died during postoperative follow-up period (mean, 78.9 months; range, 10-190 months). Good outcomes (GOS of 4 or 5) were achieved in 87.5% (42/48) of the patients at the final follow-up.

Conclusions

Microsurgical clipping is effective for incompletely coiled or recurrent aneurysms after initial coiling. For recurrent aneurysms that have coils in the neck, have no adequate neck for clipping, or cause mass effects on surrounding structures, partial or total removal of coiled mass can facilitate surgical clipping and lead to successful obliteration of the aneurysms.

Surgical Treatment of Recurrent Previously Coiled and/or Stent-Coiled Intracerebral Aneurysms: A Single-Center Experience in a Series of 75 Patients

BACKGROUND

Endovascular treated cerebral aneurysms have a greater recurrence rate compared with microsurgical clip ligation. Despite recent endovascular advances, microsurgical clip ligation might be the treatment of choice for certain previously endovascular treated recurrent aneurysms. We report on our single-center experience with 76 previously coiled and/or stent-coiled aneurysms.

OBJECTIVE

To analyze the surgical and radiologic outcome after clipping of previous endovascular treated recurrent cerebral aneurysms.

METHODS

Patients were retrospectively identified. Demographic data, aneurysm size, location, perioperative coil extraction, occlusion rate, and complication rate were recorded. Patients were divided into a previously coiled-only group (COG) and a previously stent-assisted coiled group (SAC).

RESULTS

Seventy-five patients with 76 aneurysms were included. Sixty-nine patients were included in the COG, 7 patients in the SAC group. Complete or acceptable near-complete occlusion was obtained in 95% of patients in the COG and 57% in the SAC group. Two patients in the COG (2.9%) died postoperatively of a major stroke. One patient died of rehemorrhage after wrapping of an aneurysm. Minor complications occurred in 8.7%. In the SAC group, the mortality was 0%, with 1 major stroke (14.2%), 1 minor stroke (14.2%), and 1 cranial nerve palsy (14.2%). Intraoperative coil extraction and previous stent-assisted coiling were significant predictors of complication rate (P = 0.025 and P = 0.0036 respectively). Previous stent-assisted coiling was a significant predictor of incomplete occlusion (P = 0.036).

CONCLUSIONS

Microsurgical clipping of previously endovascular treated recurrent aneurysms is an effective treatment with high obliteration rates. Previously stent-assisted coiling and intraoperative coil extraction are predictors of worse outcome and incomplete occlusion.

Management of recurrent intracranial aneurysms after coil embolization: a novel classification scheme based on angiography

OBJECTIVE

Recurrent aneurysms after coil embolization remain a challenging issue. The goal of the present study was to report the authors' experience with recurrent aneurysms after coil embolization and to discuss the radiographic classification scheme and recommended management strategy.

METHODS

Aneurysm treatments from a single institution over a 6-year period were retrospectively reviewed. Ninety-seven aneurysms that recurred after initial coiling were managed during the study period. Recurrent aneurysms were classified into the following 5 types based on their angiographic characteristics: I, pure recanalization inside the aneurysm sac; II, pure coil compaction without aneurysm growth; III, new aneurysm neck formed without coil compaction; IV, new aneurysm neck formed with coil compaction; and V, newly formed aneurysm neck and sac.

RESULTS

Aneurysm recurrences resulted in rehemorrhages in 6 cases (6.2%) of type III-V aneurysms, but in none of type I-II aneurysms. There was a significantly higher proportion of ophthalmic artery aneurysms and complex internal carotid artery aneurysms presenting as types I and II than presented as the other 3 types (63.3% vs 16.4%, p < 0.001). In contrast, for posterior communicating artery aneurysms and anterior communicating artery aneurysms, a higher proportion of type III-V aneurysms was observed than for the other 2 types, but without a significant difference in the multivariate model (56.7% vs 23.3%). In addition, giant (> 25 mm) aneurysms were more common among type I and II lesions than among type III and IV aneurysms (36.7% vs 9.0%, p = 0.001), which exhibited a higher proportion of small (< 10 mm) lesions (65.7% vs 13.3%, p < 0.001). A single reembolization procedure was sufficient to occlude 80.0% of type I recurrences and 83.3% of type II recurrences from coil compaction but only 65.6% of type III-V recurrences from aneurysm regrowth.

CONCLUSIONS

Aneurysm size and location represent the determining factors of the angiographic recurrence types. Type I and II recurrences were safely treated by reembolization, whereas type III-V recurrences may be best managed surgically when technically feasible.

Surgical Clipping of Previously Ruptured, Coiled Aneurysms: Outcome Assessment in 53 Patients

BACKGROUND

Occasionally, previously coiled aneurysms will require secondary treatment with surgical clipping, representing a more complicated aneurysm to treat than the naïve aneurysm. Patients who initially presented with a ruptured aneurysm may pose an even riskier group to treat than those with unruptured previously coiled aneurysms, given their potentially higher risk for rerupture. The objective of this study was to assess the clinical outcomes of patients who undergo microsurgical clipping of ruptured previously coiled cerebral aneurysms. In addition, we present a thorough review of the literature.

METHODS

A total of 53 patients from a single institution who initially presented with a subarachnoid hemorrhage and underwent surgical clipping of a previously coiled aneurysm between December 1997 and December 2014 were studied. Clinical features, hospital course, and preoperative and most recent functional status (Glasgow Outcome Scale score) were reviewed retrospectively.

RESULTS

The mean time interval from coiling to clipping was 2.6 years, and mean follow-up was 5.5 years (range, 0.1-14.7 years). Five patients (9.8%) presented with rebleed prior to clipping. Most patients (79.3%, 42/53) experienced good neurologic outcomes. Most showed no change (81%, 43/53) or improvement (13%, 7/53) in functional status after microsurgical clipping. One patient (2%) deteriorated clinically, and there were 2 mortalities (4%).

CONCLUSIONS

Microsurgical clipping of previously ruptured, coiled aneurysms is a promising treatment method with favorable clinical outcomes.

Therapeutic strategies for residual or recurrent intracranial aneurysms after microsurgical clipping

OBJECTIVES

Therapeutic strategies for residual or recurrent aneurysm (RRA) after microsurgical clipping have not been well established. The purpose of this study was to report our retreatment experiences with previously clipped aneurysms and to demonstrate retreatment strategies for these RRAs.

PATIENTS AND METHODS

From 1996-2016, we treated 68 RRAs after previous clipping. Among them, 34 patients underwent microsurgical retreatment, and the other 34 underwent endovascular retreatment. Radiographic images and clinical data were reviewed retrospectively to determine the treatment efficacy, clinical outcomes, and important factors for selecting the proper treatment modality.

RESULTS

The most common aneurysm location was the middle cerebral artery (50%) in the microsurgery group and the internal carotid artery (47.1%) in the endovascular surgery group (p =  0.001). In the microsurgery group, 16 (47.1%) patients had additional clipping without removal of previous clips, 17 (50.0%) had clipping with removal of previous clips, and 1 (2.9%) had bypass surgery with trapping. In the endovascular surgery group, 28 (82.4%) patients had simple coiling, 5 (14.7%) had stent-assisted coiling, and 1 (2.9%) had a flow diverter. Procedure-related complications during retreatment occurred in 4 (5.9%) patients. Complete obliteration was achieved in 51 (75.0%) patients (microsurgery group, 82.4% and endovascular surgery group, 67.6%; p =  0.002).

CONCLUSIONS

In properly selected cases, treatment of RRAs could be safely performed either by microsurgery or endovascular surgery and result in a good clinical outcome with acceptable morbidity. The decision to choose the treatment modality for RRAs after clipping is not easy but should be considered to lower the risk of retreatment.

Surgical management of recurrent aneurysms after coiling treatment

OBJECTIVE

Aneurysms that recur after coiling treatment are difficult to manage. The microsurgical technique in these cases differs significantly from that in regular aneurysm clipping. We present our experience in surgical management of aneurysms that recurred more than 1 month after coiling in a series of 19 patients.

MATERIALS AND METHODS

Between January 2004 and December 2014, 1437 patients were treated surgically for intracranial aneurysms in our institution. We performed a retrospective review of the clinical records, operation videos, and cerebral angiograms. We focused on patients in whom the initial aneurysm was treated by coiling, but the results were incomplete or the aneurysm recurred.

RESULTS

Nineteen patients underwent surgical clipping for recurrent aneurysm more than 1 month after initial coiling treatment. The sex ratio (male:female) was 0.9, and the average age was 51.3 years (range 35-72 years). One aneurysm was classified as giant (≥ 25 mm), two as large (10-25 mm), and 18 as small (≤ 10 mm). A good outcome (Glasgow Outcome Scale 4 or 5) was observed in 16 of 19 patients (84.2%).

CONCLUSION

Microsurgical clipping can be safe and effective in the management of previously coiled residual and recurrent aneurysms.

Treatment of Recurrent Intracranial Aneurysms After Clipping: A Report of 23 Cases and a Review of the Literature

OBJECTIVE

There are no established treatment strategies for aneurysms that recur after clipping. In this study, we present cases of patients who experienced recurrent aneurysms after clipping and subsequently underwent surgical intervention.

METHODS

Between 2004 and 2015, we surgically treated 23 aneurysms that recurred at a previously clipped site. Patient characteristics and clinical history were retrospectively reviewed.

RESULTS

Patients included 19 women and 4 men 45-81 years old. Aneurysms recurred 3-31 years (mean, 15.4 years) after the initial operation. For 18 cases, the first clinical presentation was a subarachnoid hemorrhage; aneurysms were incidentally diagnosed in 5 patients. Aneurysm locations were as follows: 9 on the internal carotid artery; 4 on the middle cerebral artery; 7 on the anterior communicating artery; 2 on the distal anterior cerebral artery; and 1 on the basilar artery. The reasons for retreatment included subarachnoid hemorrhage (n = 9) and aneurysm regrowth detected on follow-up examinations (n = 14). Endovascular treatment was performed in 10 cases, and direct surgery was performed in 13 cases (clipping in 8, clipping or trapping with bypass in 5). Various complex vascular reconstructions, including high-flow bypass and intracranial-intracranial in situ bypass, were performed for recurrent aneurysms.

CONCLUSIONS

In our experience, coil embolization is a safe and effective procedure for treating recurrent aneurysms. When cases are unsuitable for coil embolization, surgical treatment often requires neurosurgeons not only to overcome the general technical difficulty of reoperative clipping but also to perform challenging vascular reconstruction.

Safety and efficacy of microsurgical treatment of previously coiled aneurysms: a systematic review and meta-analysis

BACKGROUND

We conducted a systematic review of the literature to evaluate the safety and efficacy of surgical treatment of previously coiled aneurysms.

METHODS

A comprehensive review of the literature for studies on surgical treatment of previously coiled aneurysms was conducted. For each study, the following data were extracted: patient demographics, initial clinical status, location and size of aneurysms, time interval between initial/last endovascular procedure and surgery, surgical indications, and microsurgical technique. We performed subgroup analyses to compare direct clipping versus coil removal and clipping versus parent vessel occlusion, early (<4 weeks post-coiling) versus late surgery and anterior versus posterior circulation.

RESULTS

Twenty-six studies with 466 patients and 471 intracranial aneurysms were included. All of the studies were retrospective and non-comparative case-series. Patients undergoing direct clipping had lower perioperative morbidity (5.0 %, 95 % CI = 2.6-7.4 %) when compared to those undergoing coil removal and clipping (11.1 %, 95 % CI = 5.3-17.0 %) or parent vessel occlusion (13.1 %, 95 % CI = 4.6-21.6 %) (p = 0.05). Patients receiving early surgery (<4 weeks post-coiling) had significantly lower rates of good neurological outcome (77.1 %, 95 % CI = 69.3-84.8 %) when compared to those undergoing late surgery (92.1 %, 95 % CI = 89.0-95.2 %) (p < 0.01). There were higher rates of long-term neurological morbidity in the posterior circulation group (23.1 vs. 4.7 %, p < 0.01) as well as long-term neurological mortality (4.4 vs. 2.8 %, p < 0.01).

CONCLUSIONS

Our meta-analysis suggests that surgical treatment is safe and effective. Our data indicate that aneurysms that are amenable to direct clipping have superior outcomes. Late surgery was also associated with better clinical outcomes. Surgery of recurrent posterior circulation aneurysms was associated with high rates of morbidity and mortality. Given the characteristics of the included studies, the quality of evidence of this meta-analysis is limited.

Microsurgical Treatment of Previously Coiled Intracranial Aneurysms: Systematic Review of the Literature

OBJECTIVE

To assess indications, complications, clinical outcomes, and technical nuances of microsurgical treatment of previously coiled intracranial aneurysms.

METHODS

A systematic review of the literature was performed using PubMed/MEDLINE and EMBASE databases from January 1990 to December 2013. English-language articles reporting on microsurgical treatment of previously coiled intracranial aneurysms were included. Articles that involved embolization materials other than coils were excluded. Data on aneurysm characteristics, indications for surgery, techniques, complications, angiographic obliteration rates, and clinical outcomes were collected.

RESULTS

The literature review identified 29 articles reporting on microsurgical clipping of 375 previously coiled aneurysms. Of the aneurysms, 68% were small (<10 mm). Indications for clipping included the presence of a neck remnant (48%) and new aneurysmal growth (45%). Rebleeding before clipping was reported in 6% of cases. Coil extraction was performed in 13% of cases. The median time from initial coiling to clipping was 7 months. The angiographic cure rate was 93%, with morbidity and mortality of 9.8% and 3.6%, respectively.

CONCLUSIONS

Microsurgical clipping of previously coiled aneurysms can result in high obliteration rates with relatively low morbidity and mortality in select cases. Considerations for microsurgical strategies include the presence of sufficient aneurysmal tissue for clip placement and the potential need for temporary occlusion or flow arrest. Coil extraction is not needed in most cases.

Microsurgical clipping of previously coiled aneurysms

OBJECTIVE

This study sought to show and analyze the main authors' experience (P.R. and J.M.C.) in previously coiled aneurysm surgery as an emerging challenge in today's neurosurgical practice.

METHODS

Twelve female and 8 male patients, whose ages ranged from 32 to 56 years (average 43.5), underwent surgery between April 2009 and September 2012 in 2 centers. Reasons for surgery were 13 partially occluded aneurysms and 7 recanalized aneurysms.

RESULTS

There was no mortality in this series. Aneurysmal sites were 5 anterior communicating artery aneurysms, 5 posterior communicating artery aneurysms, 3 middle cerebral artery aneurysms, 6 paraclinoid carotid artery aneurysms, and 1 aneurysm in the pericallosal artery. A patient sustained a postsurgical frontal infarction with mild neurological deficit. One of the aneurysms presented with an arterial branch at the level of the aneurysmal neck; therefore, partial clipping and packing was required. Microsurgical clipping in the remaining patients was performed successfully. Eight cases required partial coil removal before clipping.

CONCLUSIONS

Surgical management of previously coiled aneurysms is an emerging challenge in neurosurgery. Incomplete or ineffective embolizations pose an increased risk for the patient, thus requiring surgical treatment. Although not advisable, coil removal might be necessary when in the vicinity of the aneurismal neck in order to place the clip correctly. The authors believe that adequate patient selection and careful preoperative planning are essential to reduce the incidence of patients with unsuccessful coils who will later need surgical treatment.

Observer agreement regarding the necessity of retreatment of previously coiled recurrent cerebral aneurysms

BACKGROUND AND PURPOSE

The decision regarding whether or not to retreat a previously treated aneurysm not only directly impacts patient care but also serves as a primary outcome measure in numerous, leading randomized controlled trials of modified coils. Our aim was to determine the degree of interobserver variability regarding the need and type of treatment for recurrent aneurysms following coil embolization.

MATERIALS AND METHODS

Twenty-seven previously treated recurrent aneurysms were identified. Five independent readers rated each aneurysm on a 5-point scale: 1, definitely do not retreat; 2, probably do not retreat; 3, unsure; 4, probably retreat; and 5, definitely retreat. The readers noted, in grades 2-5, the type of retreatment preferred, including simple coiling, balloon- or stent-assist coiling, or surgical clipping. Intraobserver agreement κ was calculated. Retreatment recommendations were evaluated between observers by using a Wilcoxon signed rank comparison. Descriptive statistics were performed for categoric treatment-type comparisons.

RESULTS

At least 2- or 3-point differences between 2 readers were present in 17 (63%) and 11 (41%) of 27 cases, respectively. The median κ was 0.27 (range, 0.04-0.43), which indicates fair agreement. Differences between readers varied, with readers 4 and 5 more often recommending retreatment compared with reviewers 1-3 (P < .05). Wide variation was noted in treatment approach, with recommendations for surgical clipping ranging from 2 (7%) to 18 (67%) of 27 cases between readers 1 and 5.

CONCLUSIONS

The current study demonstrates substantial variability among observers not only in whether to retreat a recurrent aneurysm but also how to treat it. These findings suggest that patient management varies widely across treating physicians and also calls into question the use of "retreatment" as an objective end point in clinical trials.

A novel aneurysm clip design for atheromatous, thrombotic, or previously coiled lesions: preliminary experience with the "compression clip" in 6 cases

BACKGROUND

Large and giant lesions often have thicker, atheromatous walls as well as intra-aneurysmal thrombus that combine to prevent traditional clips from closing properly in some cases.

OBJECTIVE

To report the development and use of a novel clip design specifically tailored to treat atheromatous, thrombotic, or previously coiled aneurysms.

METHODS

We retrospectively reviewed the records of 6 patients with complex aneurysms not amenable to simple neck clipping and not considered appropriate for endovascular therapy who were treated using a novel "compression" clip design. We describe the development and use of a novel aneurysm clip design with blades that are not opposed at rest to allow direct clipping of atheromatous, thrombotic, and previously coiled aneurysms.

RESULTS

Four patients had recurrent, previously coiled aneurysms; one of these also had a large thrombotic component. Two patients had complex lesions with heavy atheroma involving a portion of their aneurysms. There were no complications related to the use of the clip, and all patients did well without neurological complications. In every case, the clip allowed straightforward obliteration of the aneurysm without the need for temporary vascular occlusion, aneurysmorrhaphy, or removal of an intra-aneurysmal coil mass. All patients underwent intraoperative angiography to confirm obliteration of the aneurysm with preservation of the normal vasculature.

CONCLUSION

Atheromatous, thrombotic, and previously coiled aneurysms may not be treatable with simple neck clipping and may not be curable with endovascular therapy. For such cases, we designed a novel "compression" clip that has been used safely and successfully in our experience with good short-term follow-up.

Preliminary observation on predicting the need for coil extraction during microsurgery: the clip-coil ratio

OBJECT

Coil extraction during microsurgery for recanalized intracranial aneurysms can be associated with high morbidity. We evaluated our preliminary experience using the clip-coil ratio to predict the need for coil extraction.

METHODS

A multi-institutional retrospective review of previously coiled aneurysms that were clipped for recurrence between 2005 and 2009 was performed. The maximal height and the widths of the recanalization were measured. The largest of these dimensions was divided by the other. We defined this as the clip-coil ratio, which is a modification of the aspect ratio.

RESULTS

Thirteen patients were included in this study. The mean age of the patients was 53 years (range 41-68 years). The aneurysm locations were anterior communicating artery (n = 5), pericallosal artery (n = 2), ophthalmic artery (n = 1), and posterior communicating artery (n = 5). A clip-coil ratio >or=1.3 allowed for microsurgical clipping without coil extraction. The mean ratio in these patients was 1.6. Coil extraction was necessary in two patients with a clip-coil ratio <1.3.

CONCLUSION

In reviewing our preliminary experience, we observed that coil extraction during microsurgery was not necessary when the clip coil ratio was >or=1.3. The ratio may serve as an indirect indicator of the amount of aneurysm tissue that can be incorporated within a clip; however, given the small patient population, further studies are needed to validate this concept.

Microsurgical management of incompletely coiled and recurrent aneurysms: trends, techniques, and observations on coil extrusion

OBJECTIVE

With the growing volume of aneurysms treated with endovascular methods and the unavoidable risks of incomplete coiling or recurrence, the volume of coiled aneurysms requiring surgical management is growing. We present a consecutive surgical experience with previously coiled aneurysms to examine clinical trends, the phenomenon of coil extrusion, microsurgical techniques, and morphological features affecting clippability.

METHODS

During a 10-year period, 43 patients underwent surgical management of an incompletely coiled or recurrent aneurysm (Gurian group B). Most patients (88%) presented initially with subarachnoid hemorrhage, most commonly (28%) located in the anterior communicating artery, and 42% of aneurysms were large or giant sized.

RESULTS

Twenty-one patients had incompletely coiled aneurysms and 22 patients had recurrent aneurysms, with a mean time to recurrence of 28 months. Coil extrusion was observed in 1 of the incompletely coiled (5%) and 12 of the recurrent aneurysms (55%). Overall, 33 aneurysms were clipped directly, 7 unclippable aneurysms were bypassed, and 3 were wrapped. Three patients died (surgical mortality, 7%), 1 patient (2%) experienced permanent neurological morbidity, and the remaining 39 patients (91%) had good outcomes (mean follow-up, 4.3 years).

CONCLUSION

This study demonstrated a sharp increase in the incidence of coiled aneurysms requiring surgery, reflecting the increasing numbers of patients opting for endovascular therapy initially. Coil extrusion occurs more often than expected, is often misdiagnosed on angiography as simply compaction, and seems to be a time-dependent process not seen acutely. Direct clipping is the preferred microsurgical treatment of coiled aneurysms and may be predicted by the relationship between coil width and compaction height (C/H < 2.5, or a wedge angle < 90 degrees). We recommend a bypass strategy for unclippable coiled aneurysms because it can be executed methodically; has predictable ischemia times; and is associated with more favorable results than thrombectomy, coil extraction, and clip reconstruction.

Neurosurgical management of intracranial aneurysms following unsuccessful or incomplete endovascular therapy

The publication of the ISAT trial in 2002 has resulted in increasing numbers of patients with aneurysmal subarachnoid haemorrhage undergoing endovascular coiling, as first line treatment for aneurysm occlusion. During the first 2-year period post-ISAT, in which all suitable intracranial aneurysms were coiled first, we had to perform surgery in seven patients out of 54 who underwent initial coiling. The reasons for subsequent surgery were failed coiling, residual or recurrent aneurysm necks and delayed aneurysmal rebleeding despite coiling. We reviewed our surgical experience with the repair of these previously coiled aneurysms to identify unique technical difficulties. In particular, we found that an aneurysm height to neck ratio of less than 2:1 after coiling, and the use of stent-assisted coiling presented formidable challenges to direct clipping.

Neurosurgical treatment for aneurysm remnants or recurrences after coil occlusion

OBJECTIVE

Neurosurgical management of residual aneurysms (RA) after coiling remains a challenging issue. We present a consecutive series of 21 patients who underwent microsurgical treatment of a previously coiled aneurysm.

METHODS

We retrospectively reviewed a consecutive series of 21 patients who underwent operations for an RA after coiling between 1997 and 2007. Postcoiling follow-up imaging included brain magnetic resonance angiography and digital subtraction angiography. The decision for surgical treatment was made when an RA was significant and unsuitable for re-embolization. Data related to the RA and to the surgical technique were analyzed. Postoperative outcome was evaluated with the Glasgow Outcome Scale.

RESULTS

Twenty aneurysms were initially ruptured. Twelve had undergone complete coil occlusion, whereas 6 had a residual neck, 2 had a residual lobule, and 1 had a residual sac. The aneurysms were in the anterior circulation in 18 cases and in the posterior circulation in 3 cases. Twenty RAs were excluded with the apposition of 1 clip beneath the coils, 2 required a temporary occlusion, 2 required extraction of the coils, and 1 presented with an operative rupture. All aneurysms, except 2 that had their residual neck wrapped, were completely occluded. The postoperative Glasgow Outcome Scale score was unchanged in 90% of patients, and 2 patients sustained a moderate disability.

CONCLUSION

Microsurgical treatment of RA after endovascular treatment is effective, provided that patients are selected appropriately. The surgical treatment of recanalized aneurysms after coiling is challenging but can result in a good outcome with low morbidity and no mortality.

Retreatment of previously embolized cerebral aneurysms: the risk of further coil embolization does not negate the advantage of the initial embolization

BACKGROUND AND PURPOSE

A significant minority of aneurysms treated by endovascular means undergo additional subsequent therapy to treat aneurysm recurrence. Our study was undertaken to determine the risk of additional coil embolization of aneurysms recurring following endovascular therapy.

MATERIALS AND METHODS

Patients were identified during a 10-year period from prospectively collated data bases at 2 different neuroscience institutions. Patient outcome was obtained from the data bases or the patient's neurosurgical records. Occlusion grade was assessed at the time of treatment and at follow-up angiography as complete, near-complete, or incomplete.

RESULTS

Of a total of 1834 aneurysms in 1631 patients, 100 aneurysms in 99 patients treated between January 1996 and December 2005 required additional coiling because of an enlarging remnant and subtotal occlusion. This comprised 6% of the patients treated and 8% of the total followed. Thromboembolic events complicated 3 retreatment procedures, but all 3 patients remain independent. Ninety-five patients were followed for 8-103 months (mean, 42.3 months) by conventional or MR angiography.

CONCLUSION

Coil embolization of aneurysm recurrences has a low complication rate and leads to satisfactory occlusion in most cases. The risk from additional coil embolization does not negate the advantage of the initial embolization.

Technical challenges to surgical clipping of aneurysmal regrowth with coil herniation following endovascular treatment - a case report

In recent years, technical developments have made endovascular procedures attractive therapeutic options and enabled the endovascular surgeon to redefine the management of cerebral aneurysms. However, as the number of aneurysms undergoing endovascular therapy has grown, so has the number of patients with incompletely treated aneurysms who are presenting for further management. In cases of failure of endovascular treatment caused by either incomplete occlusion or regrowth of the aneurysm, a complementary treatment is often necessary. Surgical treatment of these patients is challenging. We present a case of a ruptured posterior cerebral artery aneurysm treated initially with endovascular coiling that left behind significant residual aneurysmal sac. Regrowth of the aneurysm documented on follow-up was treated surgically. At surgery, the coil was found to have herniated through the aneurysmal sac into the subarachnoid space, and the aneurysm was successfully clipped without removing the coils. We review the regrowth of aneurysms following endovascular therapy and potential problems and challenges of surgically managing these lesions.

Late Recurrence of Subarachnoid Hemorrhage after Treatment for Ruptured Aneurysms: Patient Characteristics and Outcomes

OBJECTIVE

Patients with subarachnoid hemorrhage (SAH) who have been successfully treated for all detected aneurysms are at risk for recurrence of SAH. We assessed the characteristics, complications of re-treatment, and outcomes of patients with recurrent SAH as important factors in determining whether to screen patients for new aneurysms.

METHODS

We studied patients admitted between 1987 and 2002 to three hospitals in the Netherlands for recurrent SAH. Patients had received treatment previously for all aneurysms identified after initial SAH. We collected data for age, sex, risk factors, site, and number of the aneurysm(s), time between the first and the second SAH, complications of re-treatment, and outcome after recurrent SAH.

RESULTS

We identified 30 patients: 27 women and 3 men. Thirty-two aneurysms were documented; 19 were classified as de novo, 8 were classified as regrowth, and 5 had been missed in retrospect. The mean time between the first and the second SAH was 7.8 years (range, 0.25-17 yr for all aneurysms and 2.8-14 yr for de novo aneurysms). Nine patients (30%) had a family history of SAH. No specific complications were reported with reoperation in 21 patients. Ten patients (33%) died, 4 patients (14%) were severely disabled, and 16 patients (53%) had good outcomes.

CONCLUSION

Among patients admitted with recurrent SAH, there is a predominance of women and patients with familial SAH. Reoperation is not associated with specific complications. Outcome after recurrent SAH is similar to that after initial SAH.

Surgical Clipping of a Recurrent Small Saccular Aneurysm After Repeated Coil Embolization-Case Report-

A 59-year-old healthy woman presented with sudden onset of severe headache. Computed tomography and digital subtraction angiography (DSA) demonstrated subarachnoid hemorrhage (grade I according to the Hunt and Hess classification) due to a ruptured small right posterior cerebral artery (PCA) aneurysm. The ruptured PCA aneurysm was completely embolized with three Guglielmi detachable coils (GDCs). However, follow-up DSA 3 months after the initial coiling confirmed refilling of the aneurysm. The aneurysm was successfully re-embolized with two GDCs. Follow-up DSA 10 months later revealed regrowth of the aneurysm. Surgical clipping was performed without compromising the parent vessels. Long-term angiographic follow up is necessary even in patients with small saccular aneurysms which are apparently completely embolized by endovascular coil treatment.