Endovascular coil embolization after clipping: endovascular treatment of incompletely clipped or recurred cerebral aneurysms

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.

Outcome of retreatment for recurrent saccular cerebral aneurysms: a propensity score-matched analysis

Although endovascular or surgical treatment has been performed for preventing the rupture of saccular cerebral aneurysms (sCA), in some patients, the aneurysms may recur and require retreatment. We aimed to investigate the clinical and radiological outcomes of treating recurrent sCA. We retrospectively evaluated the data of 52 patients with 60 recurrent sCAs who were retreated and 1534 patients with 1817 sCAs who received initial treatment. The primary outcome was a recurrence of the aneurysm. Secondary outcomes were an additional treatment, rupture after treatment, and a neurological worsening, which was defined as an increase of 1 or more scores using the modified Rankin Scale at 12-month. Safety outcomes included postoperative ischemic and hemorrhagic complications. We compiled the 120 (60 each) propensity score-matched cohort based on a propensity score for the treatment of recurrent sCA. In the propensity score-matched cohort, recurrence after treatment was observed in 25% and 6.7% of cases in the retreatment and initial treatment groups, respectively. The odds ratio of recurrence after treatment was 4.7 (95% CI, 1.4-15; P = 0.011). The secondary and safety outcomes were not significantly different between the two groups. This study showed that the treatment of recurrent sCA was a risk factor for recurrence after treatment but not for additional treatment, rupture after treatment, or neurological worsening. Although decision-making regarding the treatment varies depending on the institutional protocols and personal experience of the physicians, endovascular or surgical retreatment could be performed without hesitation.

Treatment of Recurrent Intracranial Aneurysms After Neck Clipping: Novel Classification Scheme and Management Strategies

BACKGROUND

Recurrent aneurysms after initial clipping have been discussed as an important issue in the surgical management of aneurysm.

OBJECTIVE

To report our experience with recurrent cerebral aneurysms after neck clipping and to discuss classification and recommended management.

METHODS

Aneurysm treatments from a single institution over a 20-year period were retrospectively reviewed. Twenty-three recurrent aneurysms in 23 patients were managed during the study period. Recurrent aneurysms were classified using the concepts of closure line and closure plane, as follows. Type 1: neck situated in an almost different site from the previous clip. Type 2: existing closure plane and reconstructive closure plane are almost the same. Type 3: existing closure plane and reconstructive closure plane cross (type 3a); in rare cases, the existing closure line is sufficiently distant from the neck (type 3b). Type 4: no reconstructive closure line is identifiable.

RESULTS

Nine patients presented with subarachnoid hemorrhage at recurrence. The mean interval to recurrence was 15.0 years. Management comprised clipping with elective subsequent old-clip removal (n = 7), clipping with preceding old-clip removal (n = 2), bypass occlusion (n = 1), coating (n = 1), combined surgery (n = 1), endovascular surgery (n = 4), and observation (n = 3). Therapeutic intervention was not indicated in 4 patients. Types 3a and 4 required more complex surgical procedures or coil embolization. Procedural complications were observed in 2 patients.

CONCLUSION

A small but definite propensity toward recurrence after neck clipping exists, and most recurrent aneurysms require some form of retreatment. The novel classification scheme may provide conceptual clarity and therapeutic guidance for decision making.

Coil Embolization in Patients with Recurrent Cerebral Aneurysms Who Previously Underwent Surgical Clipping

BACKGROUND AND PURPOSE

Surgical revision of recurrent cerebral aneurysms is technically difficult. Therefore, coil embolization has been used as an alternative in these cases. The aim of this study was to evaluate the clinical and angiographic outcomes of coil embolization in patients with recurrent cerebral aneurysms after microsurgical clipping.

MATERIALS AND METHODS

Between May 1999 and February 2016, nineteen patients with 19 recurrent aneurysms who previously underwent surgical clipping were treated by coil embolization.

RESULTS

Nine patients presented with subarachnoid hemorrhage (47.4%). The interval between surgical clipping and coil embolization was 143.5 ± 66.1 months (range, 43-276 months). Single- or double-catheter coil embolization was performed in 16 patients. A balloon (n = 1) and stents (n = 2) were used to assist the coil embolization in 3 patients. Immediate radiologic findings after coil embolization showed complete occlusion in 10 patients, a residual neck in 8 patients, and a residual sac in 1 patient. Procedure-related permanent morbidity occurred in 1 patient. The mean clinical follow-up was 58.3 ± 38.8 months. Poor clinical outcomes (modified Rankin Scale score = ≥3) at the end of the clinical follow-up were reported in 5 patients (26.3%). Angiographic follow-up was available for 12 patients (63.2%). Major recurrence was detected in 5 patients (41.7%), and a tendency for aneurysm regrowth rather than coil compaction was noted in all cases.

CONCLUSIONS

In our series, coil embolization for recurrent aneurysms after surgical clipping was feasible but had a high recurrence rate and tended to result in aneurysm regrowth rather than coil compaction.

Flow-diverter stents in the endovascular treatment of remnants in previously clipped ruptured aneurysms: a feasibility study

BACKGROUND

The rate of intracranial aneurysm remnants/recurrences after microsurgical clipping varies widely. The optimal management for these patients remains a matter of debate. Repeat surgery in particular bears a high risk of periprocedural complications due to anatomical distortion from prior procedures. This study aims to evaluate the risk-benefit profile of flow-diverter stents in these patients.

METHODS

The patient database of our neurovascular centre was queried to identify patients with clipped aneurysms who subsequently underwent endovascular treatment with intraluminal flow-diverter stents. The outcome analysis consisted of an assessment of clinical parameters (modified Rankin scale) and the post-interventional angiographic occlusion status (according to the Raymond-Roy occlusion classification).

RESULTS

Six patients underwent endovascular treatment with flow-diverter stents of recurrent aneurysms after clipping. Treatment was necessary in two patients due to progressive neurological deficits, and due to angiographic proof of an increasing aneurysm size in the other four patients. Median aneurysm size was 0.45 cm. All patients had a prior history of subarachnoid haemorrhage. The time from primary clipping to recurrence was 10.6 years. Complete radiological aneurysm occlusion was feasible in five out of six cases. Two patients who had experienced pre-interventional neurological deficits showed a complete remission of symptoms on last follow-up. No periprocedural morbidity or mortality was recorded and no patient required retreatment within the median follow-up.

CONCLUSION

This case series suggests that endovascular treatment with flow-diverter stents of aneurysm remnants after previous microsurgical clipping is a feasible treatment concept with a low-risk profile, which might prevent the treatment burden and risks of repeat surgery.

Stent-assisted coil embolization of a recurrent posterior cerebral artery aneurysm following surgical clipping

Posterior cerebral artery (PCA) aneurysms are rare, and direct surgery of these is considered difficult. Coil embolization of PCA aneurysms is becoming popular. However, it is difficult to completely obliterate the aneurysm while preserving the flow of the parent artery in large or giant PCA aneurysms with a wide neck with this technique. We report a case of a large and wide-necked PCA aneurysm with multiple recurrences following successful surgical clipping and coil embolization. A 77-year-old man with a large unruptured right PCA (P2) aneurysm was successfully treated by surgical clipping. Postoperative digital subtraction angiography (DSA) showed complete aneurismal occlusion. Four years afterward, the aneurysm recurred and grew toward the contralateral. Surgical retreatment of this complicated aneurysm was considered difficult, with a substantial risk of complications. Therefore, the aneurysm was treated with an endovascular procedure. Because simple coil embolization was not expected to achieve satisfactory obliteration of the aneurysm with preservation of parent artery patency, we used stent-assisted coil embolization. The patient tolerated the treatment well. On DSA obtained six months after the first endovascular treatment, coil compaction and recanalization of the aneurysm were detected. A second coil embolization was successfully performed without any complications. The aneurysm was stable during the next six-month follow-up. Stent-assisted coil embolization may be feasible and effective for such postoperatively complicated aneurysms.