Parent artery occlusion is not obsolete in giant aneurysms of the ICA. Experience with very-long-term follow-up

Exploring the latest findings on endovascular treatments for giant aneurysms: a review

Giant intracranial aneurysms represent a very challenging aspect of aneurysmal pathophysiology with very high mortality and morbidity if left untreated. Their variety in clinical presentation (subarachnoid hemorrhage, cranial nerve palsy, etc.) and pathological and imaging properties (location, anatomy, presence of collateral circulation) pose serious questions regarding the best treatment option. Admirable advances have been achieved in surgical techniques, while endovascular modalities with flow diversion techniques have become widely used. However, there is still lack of data regarding whether a single endovascular technique can be the universal treatment for such cases. In this review, we aim to summarize the current funds of knowledge concerning giant intracranial aneurysms and the role of endovascular management in their treatment.

Endovascular Parent Vessel Occlusion Versus Flow Diversion in the Treatment of Large and Giant Aneurysms: A Randomized Comparison

OBJECTIVE

Parent vessel occlusion (PVO) is a time-honored treatment for unclippable or uncoilable intracranial aneurysms. Flow diversion (FD) is a recent endovascular alternative that can occlude the aneurysm and spare the parent blood vessel. Our aim was to compare outcomes of FD with endovascular PVO.

METHODS

This is a prespecified treatment subgroup analysis of the Flow diversion in Intracranial Aneurysms trial (FIAT). FIAT was an investigator-led parallel-group all-inclusive pragmatic randomized trial. For each patient, clinicians had to prespecify an alternative management option to FD before stratified randomization. We report all patients for whom PVO was selected as the best alternative treatment to FD. The primary outcome was a composite of core-lab determined angiographic occlusion or near-occlusion at 3-12 months combined with an independent clinical outcome (mRS<3). Primary analyses were intent-to-treat. There was no blinding.

RESULTS

There were 45 patients (16.2% of the 278 FIAT patients randomized between 2011 and 2020 in 3 centers): 22 were randomly allocated to FD and 23 to PVO. Aneurysms were mainly large or giant (mean 22 mm) anterior circulation (mainly carotid) aneurysms. A poor primary outcome was reached in 11/22 FD (50.0%) compared to 9/23 PVO patients (39.1%) (RR: 1.28, 95% CI [0.66-2.47]; P = 0.466). Morbidity (mRS >2) at 1 year occurred in 4/22 FD and 6/23 PVO patients. Angiographic results and serious adverse events were similar.

CONCLUSIONS

The comparison between PVO and FD was inconclusive. More randomized trials are needed to better determine the role of FD in large aneurysms eligible for PVO.

Perioperative and long-term complications following therapeutic internal carotid artery occlusion

BACKGROUND

Parent artery occlusion (PAO) is an effective treatment for hemorrhagic diseases associated with the internal carotid artery. There are several reports of long-term cerebral infarction or the formation of de novo cerebral aneurysms following PAO.

MATERIALS AND METHODS

We retrospectively reviewed these complications in 38 patients who underwent PAO for therapeutic treatment. We investigated perioperative cerebral infarctions, long-term cerebral infarctions, and de novo aneurysms.

RESULTS

The mean age of the patients was 64.0 years, and 25 patients (65.8%) were female. The causative diseases were unruptured (n = 19; 50.0%) and ruptured (n = 8; 21.1%) aneurysms. PAO was performed after ischemic tolerance was assessed with balloon test occlusion (BTO), and BTO was performed in 34 patients, of whom 25 (73.5%) had ischemic tolerance. Twenty-six patients (68.4%) were treated with PAO alone, eight (23.5%) with low-flow bypass, and six (17.6%) with high-flow bypass. Perioperative complications occurred in five patients (13.2%): two of the 26 patients (7.7%) who underwent scheduled treatment and three of the 12 patients (25.0%) who underwent emergency treatment. One patient (2.6%) had long-term de novo aneurysm, and none developed cerebral infarction.

CONCLUSIONS

These results showed that the assessment of ischemic tolerance by performing BTO and appropriate revascularization in scheduled treatments are important to reduce perioperative and long-term cerebral infarctions. PAO must be performed with greater caution in emergency treatment.

Combined standard bypass and parent artery occlusion for management of giant and complex internal carotid artery aneurysms

BACKGROUND

Complex aneurysms do not have a standard protocol for treatment. In this study, we investigate the safety and efficacy of microsurgical revascularization combined with parent artery occlusion (PAO) in giant and complex internal carotid artery (ICA) aneurysms.

METHODS

Between 1998 and 2017, 41 patients with 47 giant and complex ICA aneurysms were treated by an a priori planned combined treatment strategy. Clinical and radiological outcomes were stratified according to mRS and Raymond classification. Bypass patency was assessed. Median follow-up time was 3.9 years.

RESULTS

After successful STA-MCA bypass, staged endovascular (n=37) or surgical (n=1) PAO was executed in 38 patients following a negative balloon occlusion test. Intolerance to PAO led to stent/coil treatments in two patients. Perioperative bypass patency was confirmed in 100% of completed STA-MCA bypass procedures. Long-term overall bypass patency rate was 99%. Raymond 1 occlusion and good outcome were achieved in 95% and 97% (mRS 0-2) of cases, respectively. No procedure-related mortality was encountered. Eighty-four percent of patients with preoperative cranial nerve compression syndromes improved during follow-up.

CONCLUSIONS

The combined approach of STA-MCA bypass surgery followed by parent artery occlusion achieves high aneurysm occlusion and low morbidity rates in the management of giant and complex ICA aneurysms. This combined indirect approach represents a viable alternative to flow diversion in patients with cranial nerve compression syndromes or matricidal aneurysms, and may serve as a backup strategy in cases of peri-interventional complications or lack of suitable endovascular access.

Giant internal carotid aneurysm: endovascular parent artery occlusion after failed treatment using a flow diverter-case report

Treatment of giant aneurysms is challenging. While parent vessel reconstruction is the primary therapeutical target, the parent artery occlusion (PAO) is considered the next treatment option. We report a case of a 56-year-old woman with a right-sided non-ruptured giant aneurysm of the cavernous internal carotid artery. After failed aneurysm treatment by vessel remodeling through a flow diverter stent, we decided upon aneurysm coiling and PAO. Prior to the procedure, a successful balloon occlusion test (BOT) was performed, and in the second stage, just before occluding the parent artery, the BOT with induced hypotension was repeated. We achieved a good angiographic result and successful outcome without neurological deficit. In the case of failed treatment of giant aneurysm by vessel reconstruction, PAO is a therapeutical option. Prior to the vessel occlusion, a BOT with induced arterial hypotension challenge should be performed.

The Rate of Symptomatic Ischemic Events after Passing Balloon Test Occlusion of the Major Intracranial Arteries: Meta-Analysis

BACKGROUND

Balloon test occlusion is a widely used method for predicting tolerance of vessel occlusion in the treatment of aneurysms, fistulae, and head and neck neoplasms. However, the false-negative rate is variably reported due in part to the diversity of perfusion monitoring methods.

OBJECTIVE

To evaluate the rate of symptomatic ischemic events after a negative balloon test occlusion and determine whether perfusion monitoring methods contribute to differences in these rates.

METHODS

PubMed was systematically searched for studies between 1990 and 2020 that reported rates of ischemic outcomes of parental vessel occlusion in patients who passed balloon test occlusion. A generalized linear mixed model meta-analysis was performed. Results were expressed as the rate of symptomatic ischemic events after parental vessel occlusion without vessel bypass in patients who passed balloon test occlusion.

RESULTS

Thirty-two studies met the inclusion criteria. The overall pooled rate of ischemic events after passing balloon test occlusion was 3.7% (95% confidence interval [CI]: 1.7-7.8). This rate was 3.8% (95% CI: 1.1-12.8) when monitored with angiography, 2.2% (95% CI: 0.4-10.2) when monitored by a form of computed tomography, and 5.3% (95% CI: 1.2-20.4) when monitored by 2 or more methods of perfusion assessment. The complication rate of balloon test occlusion was 0.8% (95% CI: 0.2-2.7).

CONCLUSIONS

Balloon test occlusion results in a low rate of subsequent ischemic events, without conclusive evidence of variation between methods of perfusion assessment. The choice of method should focus on reduction of complication risk, experience of the interventional team, and avoidance of prolonged test occlusion times.

Bypass Surgery for Complex Internal Carotid Artery Aneurysms: 39 Consecutive Patients

OBJECTIVE

Bypass surgery is a special technique used to treat complex internal carotid artery (ICA) aneurysms. The aim of this retrospective study is to provide a comprehensive description of treatment and outcome of complex ICA aneurysms at different ICA segments (cavernous, supraclinoid, ICA bifurcation) treated with bypass procedures.

METHODS

We identified 39 consecutive patients with 41 complex ICA aneurysms that were treated with 44 bypass procedures between 1998 and 2016. We divided the aneurysms into 3 anatomic subgroups to review our treatment strategy. All the imaging studies and medical records were reviewed for relevant information.

RESULTS

The aneurysm occlusion (n = 34, 83%) or flow modification (n = 5, 12%) was achieved in 39 aneurysms (95%). The long-term bypass patency rate was 68% (n = 30). Minor postoperative ischemia or hemorrhage was commonly seen (n = 20, 51%), but large-scale strokes were rare (n = 1, 3%). Preoperative dysfunction of extraocular muscles (cranial nerves III, IV, and VI) showed low-to-moderate improvement rates (20%-50%). Preoperative vision disturbance (cranial nerve II) improved seldom (22%). At the latest follow-up (mean; 51 months) 29 patients (74%) were independent (modified Rankin Scale ≤2).

CONCLUSIONS

Bypass surgery for complex ICA aneurysms is a feasible treatment method with an acceptable risk profile. Patients should be informed of the uncertainty related to improvement of pretreatment cranial nerve dysfunctions.

Comparison of Safety and Effectiveness of Endovascular Treatments for Unruptured Intracranial Large or Giant Aneurysms in Internal Carotid Artery

PURPOSE

To analyze and compare safety and efficacy of different endovascular treatment modalities for unruptured intracranial large or giant aneurysms.

METHODS

We retrospectively reviewed 126 consecutive patients with 128 large (15-24 mm) or giant (≥25 mm) aneurysms that were treated with different endovascular procedures between January 2014 and February 2017. We compared clinical and angiographic outcomes and occurrence of technical events among 3 treatment modalities.

RESULTS

Complete occlusion at last follow-up was achieved in 65.6%, 90.5%, and 72.0% of aneurysms in stent-assisted coiling, parent artery occlusion, and Pipeline embolization device (PED) groups (P = 0.119). Complete occlusion rate at 6-month follow-up (odds ratio = 1.81, P = 0.396) and at last angiographic follow-up (odds ratio = 3.64, P = 0.123), was not superior with parent artery occlusion compared with PED. Retreatment rate was significantly different among all groups (P < 0.001); the rate was highest in the stent-assisted coiling group (21.9%). Rates of hemorrhagic events and ischemic events were not significantly different among groups (P = 0.581). Mass effect exacerbation was more frequently seen in the stent-assisted coiling group (24.4% vs. 7.7% and 3.3%, P = 0.004). Major complication rate was higher in the parent artery occlusion group compared with the PED group, but the difference was not statistically significant (19.2% vs. 16.4%, odds ratio = 1.21, P = 0.763). Rate of technical events was significantly different in the 3 groups (P = 0.0437), and technical events occurred more often in the PED group (18.0%).

CONCLUSIONS

For large and giant aneurysms located in the internal carotid artery, outcome for endovascular treatment remains poor, even with the introduction of PED.

Is surgical parent artery occlusion effective for intracranial aneurysms measuring over 10 mm in size? Result from long-term follow-up of size changes and outcomes

BACKGROUND

There have been no long-term follow-up reports pertaining to chronological size changes in large or giant unruptured intracranial aneurysms treated with surgical parent artery occlusion (PAO). The object of this study is to investigate the utility and safety of surgical PAO by conducting a long-term follow-up of chronological aneurysm size changes and outcomes.

METHODS

A retrospective study of 21 unruptured intracranial aneurysms measuring over 10 mm (20 patients) treated with surgical PAO in the period 2012-2017 was conducted. For aneurysms presenting with anterior circulation, high/low flow bypass was chosen and carried out concomitantly on the basis of preoperative balloon occlusion test results. Aneurysm size before and after surgery was evaluated chronologically using maximum diameter measurements taken from the same slice of MRI T2-weighted images. Moreover, post-surgery outcomes were evaluated according to a modified Rankin scale (mRS) at discharge.

RESULTS

PAO aiming for blind-alley formation was performed in 20 of 21 aneurysms (95.2%). Aneurysm size reduction was confirmed in 20 aneurysms (95.2%) after proper PAO, with an average reduction rate of 63.1% (range, 28-95%), during an average follow-up period of 27 months (range, 4-54 months). Eighteen (90.4%) of the 20 patients with 21 aneurysms returned to previous life with mRS score 0-2. With regard to preoperative symptoms, diplopia and visual impairment had improved in three patients (50%) and one patient (100%), respectively. Ischemic complications had occurred in five patients, two (9.6%) of whom were symptomatic and three (14.3%) were asymptomatic. The mortality rate in this study was 0%.

CONCLUSIONS

Surgical PAO for unruptured intracranial aneurysms measuring over 10 mm has been shown to be an effective method of treatment, eliciting a reduction in aneurysm size.

Parent Artery Occlusion for Unruptured Cerebral Aneurysms: Results of the Japanese Registry of Neuroendovascular Therapy 3

Although the current standard treatment for unruptured aneurysms comprises surgical clipping or endovascular coiling, these techniques are not suitable for some cases, such as large, giant, and fusiform aneurysms. Endovascular parent artery occlusion (PAO), which includes internal trapping and proximal occlusion, is a well-established alternative treatment for such cases. Here, we retrospectively reviewed PAO cases from the Japanese Registry of Neuroendovascular Therapy 3, a nation-wide survey of all neuroendovascular therapy cases between 2010 and 2014. This dataset included 274 procedures with a mean patient age of 57.1 years and 55.4% female patients. For the treatment strategy, internal trapping was selected in 213 aneurysm cases (77.7%) and proximal occlusion in 61 aneurysm cases (22.2%). Most of the procedures were successfully completed (272/274: 99.2%). Immediately after treatment, angiographical complete occlusion was achieved in 248 cases (90.5%). Although the feasibility of this technique was excellent, there were 60 periprocedural complications (21.8%), including 48 ischemic complications (17.5%), seven hemorrhagic complications (2.5%). Overall, morbidity and mortality at 30 days postoperative were 5.8% and 0.7%, respectively. Among the pretreatment variables, a patient age of 70 and older was associated with ischemic complications [odds ratio (OR); 2.34, 95% confidence interval (CI); 1.02-5.25; P = 0.04] and a small aneurysm size (<5 mm) was associated with hemorrhagic complications (OR; 9.85, 95% CI; 1.07-221.0; P = 0.04) by multivariate analysis. In conclusion, PAO for unruptured cerebral aneurysms is feasible, but is associated with a complication rate of approximately 20%. Various alternative treatment options should be carefully considered with deconstructive strategies.

Endovascular Treatment of Very Large and Giant Intracranial Aneurysms: Comparison between Reconstructive and Deconstructive Techniques-A Meta-Analysis

BACKGROUND

The safety and efficacy of reconstructive and deconstructive endovascular treatments of very large/giant intracranial aneurysms are not completely clear.

PURPOSE

Our aim was to compare treatment-related outcomes between these 2 techniques.

DATA SOURCES

A systematic search of 3 data bases was performed for studies published from 1990 to 2017.

STUDY SELECTION

We selected series of reconstructive and deconstructive treatments with >10 patients.

DATA ANALYSIS

Random-effects meta-analysis was used to analyze occlusion rates, complications, and neurologic outcomes.

DATA SYNTHESIS

Thirty-nine studies evaluating 894 very large/giant aneurysms were included. Long-term occlusion of unruptured aneurysms was 71% and 93% after reconstructive and deconstructive treatments, respectively (P = .003). Among unruptured aneurysms, complications were lower after parent artery occlusion (16% versus 30%, P = .05), whereas among ruptured lesions, complications were lower after reconstructive techniques (34% versus 38%). Parent artery occlusion in the posterior circulation had higher complications compared with in the anterior circulation (36% versus 15%, P = .001). Overall, coiling yielded lower complication and occlusion rates compared with flow diverters and stent-assisted coiling. Complication rates of flow diversion were lower in the anterior circulation (17% versus 41%, P < .01). Among unruptured lesions, early aneurysm rupture (within 30 days) was slightly higher after reconstructive treatment (5% versus 0%, P = .08) and after flow diversion alone compared with flow diversion plus coiling (7% versus 0%).

LIMITATIONS

Limitations were selection and publication biases.

CONCLUSIONS

Parent artery occlusion allowed high rates of occlusion with an acceptable rate of complications for unruptured, anterior circulation aneurysms. Coiling should be preferred for posterior circulation and ruptured lesions, whereas flow diversion is relatively safe and effective for unruptured anterior circulation aneurysms.

Endovascular management of extracranial occlusions at the hyperacute phase of stroke with tandem occlusions

BACKGROUND AND PURPOSE

The management of cervical artery occlusions in hyperacute stroke with tandem cervical/intracranial occlusions has not yet become standardized, especially when the circle of Willis is effective.

METHODS

We retrospectively analyzed the safety and accuracy of current approaches to manage the cervical occlusion in consecutive patients with tandem occlusions addressed for intracranial mechanical thrombectomy (MT) in our department from January 2012 to May 2017. The different approaches that could be performed in a same patient during the same procedure or hospitalization were analyzed separately.

RESULTS

We reported 64 approaches to manage the cervical occlusion in 49 patients with tandem occlusion (14% of MT): medical treatment alone in 16/64 (25%), stenting/angioplasty in 16/64 (25%), occlusion with coils in 12/64 (19%), angioplasty alone in 9/64 (14%), stent-retriever in 8/64 (12%), and/or thromboaspiration in 3/64 (5%). Early ipsilateral embolic recurrence occurred after 9/64 (14%) of them. It was strongly associated with the presence of a cervical intraluminal thrombus (P=0.001) and was then lower after occlusion with coils and stent-retriever compared to medical treatment alone and thromboaspiration (P=0.002). Occlusion with coils had a lower rate of radiological intracranial hemorrhage at 48-hour compared to other approaches (P=0.009). The 3-month rates of favorable outcome (P=0.806) and mortality (P=0.878) were similar. One delayed stroke was imputable to an occlusion with coils, for a median (Q1-Q3) follow-up of 10 (3-20) months.

CONCLUSIONS

Cervical occlusion with coils and thrombectomy with stent-retrievers may be relevant to prevent early embolic recurrence in cervical occlusions with intraluminal thrombus. Stent-retrievers should be further assessed as a first-line approach, since delayed stroke may occur following occlusion with coils. Medical treatment alone may be sufficient when no cervical intraluminal thrombus is present, the Willis polygon is effective, and the cervical occlusion can be crossed easily to perform the intracranial thrombectomy.

Bypass Surgery for Complex Intracranial Aneurysms: 15 Years of Experience at a Single Institution and Review of Pertinent Literature

BACKGROUND

Bypass surgery is a treatment option for complex intracranial aneurysms.

OBJECTIVE

To determine the utility of bypass surgery for the treatment of complex intracranial aneurysms and to review the literature on this topic.

METHODS

Sixty-two patients were included in this retrospective study. Unruptured aneurysms were dominant (80.6%), and the internal carotid artery was the most common location of the aneurysm (56.4%), followed by the middle cerebral artery (21.0%). The mean maximal diameter of the aneurysms was 20.5 ± 11.4 mm. The clinical and angiographic states were evaluated preoperatively, immediately after surgery (within 3 days) and at the last follow-up. The mean angiographic and clinical follow-up duration was 34.2 ± 38.9 and 46.5 ± 42.5 months, respectively.

RESULTS

Sixty-one patients (98.3%) underwent extracranial–intracranial bypass, and 1 underwent intracranial–intracranial bypass. At the last follow-up angiography, 58 aneurysms (93.5%) were completely obliterated and 4 were incompletely obliterated, with a graft patency of 90.3%. Surgical mortality was 0 and permanent morbidity was 8.1%. A good clinical outcome (Karnofsky Performance Scale ≥ 70 and modified Rankin Scale score ≤ 2) was achieved in 91.9% of patients (n = 57).

CONCLUSION

With a proper selection of bypass type, bypass-associated treatment can be a good alternative for patients with complex intracranial aneurysms when conventional microsurgical clipping or endovascular intervention is not feasible.

Endovascular parent-artery occlusion of large or giant unruptured internal carotid artery aneurysms. A long-term single-center experience

The development of stent-like devices has increased treatment options for complex internal carotid artery (ICA) aneurysms, but the optimal treatment remains unclear. The purpose of this study was to evaluate the safety and efficacy of endovascular parent-artery occlusion (PAO) for ICA aneurysms. We retrospectively reviewed 28 patients with unruptured ICA aneurysms ⩾10mm treated with PAO between April 2002 and March 2015 at our institution. Patients who developed neurologic symptoms or with venous-phase delay >2s during balloon test occlusion were not treated by PAO. Patients with venous-phase delays of 1-2s underwent superficial temporal artery to middle cerebral artery (STA-MCA) bypass prior to PAO. The median patient age was 65 (range, 26-84)years. Nineteen aneurysms (68%) were located in the cavernous segment. The median aneurysm size was 25 (range 11-40)mm. Venous-phase delay of 1-2s was observed in five patients. Perioperative ischemic complications (N=9, 32%), which occurred within 30days after treatment, were significantly associated with venous-phase delays of 1-2s (p<0.01) and history of hypertension (p<0.01). Six-month morbidity was observed in one (3.6%) patient. Complete occlusion at final follow-up and delayed (i.e. ⩾31days after treatment) ischemic events were observed in 100% and 0% of patients, respectively, over a median period of 63 (range, 6-147) months. Despite the high frequency of perioperative ischemic episodes, endovascular PAO with selective use of STA-MCA bypass showed excellent long-term outcomes in patients with unruptured ICA aneurysms ⩾10mm.

Point-by-point parent artery/sinus obliteration using detachable, pushable, 0.035-inch coils

BACKGROUND

Parent artery occlusion for intractable aneurysms or sinus packing for dural arteriovenous fistulas (DAVFs) is sometimes difficult and requires many expensive coils to accomplish complete occlusion. To help solve these problems, we reviewed our experience using 0.035-inch coil (0.035 coil; Boston Scientific, San Leandro, CA, USA), which has been used in cardiovascular and abdominal lesions.

METHODS

These 0.035 coils were preferably used in addition to the detachable and fibered coils for patients with intractable aneurysms, traumatic vessel blowout, and DAVF. Our strategy was as follows: (1) detachable coils were deployed first for the ideal anchoring of the coils; (2) small fibered coils were additionally deployed to stabilize the coil mass; (3) 0.035 coils were deployed to complete the occlusion.

RESULTS

From January 2012 to December 2013, seven consecutive patients were treated by endovascular embolization with 0.035 coils. Reasons for intervention were parent artery occlusion for carotid blowout (n = 1), internal carotid artery aneurysm (n = 2), traumatic vertebral artery injury (n = 2), vertebral AVF (n = 1), and transverse sinus-sigmoid sinus DAVF (n = 1). In our cases, a mean of 20.1 ± 8.5 coils per vessel were placed, and mean total coil length was 258.4 ± 91.5 cm per vessel. All procedures were safely performed and complete occlusions achieved.

CONCLUSIONS

From our initial experience and treatment results, we believe endovascular parent artery occlusion or sinus packing with 0.035 coils to be useful in terms of reducing the number and expense of coils and also accomplishing immediate occlusion.

Aneurysm Study of Pipeline in an Observational Registry (ASPIRe)

BACKGROUND AND OBJECTIVE

Few prospective studies exist evaluating the safety and efficacy of the Pipeline Embolization Device (PED) in the treatment of intracranial aneurysms. The Aneurysm Study of Pipeline In an observational Registry (ASPIRe) study prospectively analyzed rates of complete aneurysm occlusion and neurologic adverse events following PED treatment of intracranial aneurysms.

MATERIALS AND METHODS

We performed a multicenter study prospectively evaluating patients with unruptured intracranial aneurysms treated with PED. Primary outcomes included (1) spontaneous rupture of the Pipeline-treated aneurysm; (2) spontaneous nonaneurysmal intracranial hemorrhage (ICH); (3) acute ischemic stroke; (4) parent artery stenosis, and (5) permanent cranial neuropathy. Secondary endpoints were (1) treatment success and (2) morbidity and mortality at the 6-month follow-up. Vascular imaging was evaluated at an independent core laboratory.

RESULTS

One hundred and ninety-one patients with 207 treated aneurysms were included in this registry. The mean aneurysm size was 14.5 ± 6.9 mm, and the median imaging follow-up was 7.8 months. Twenty-four aneurysms (11.6%) were small, 162 (78.3%) were large and 21 (10.1%) were giant. The median clinical follow-up time was 6.2 months. The neurological morbidity rate was 6.8% (13/191), and the neurological mortality rate was 1.6% (3/191). The combined neurological morbidity/mortality rate was 6.8% (13/191). The most common adverse events were ischemic stroke (4.7%, 9/191) and spontaneous ICH (3.7%, 7/191). The complete occlusion rate at the last follow-up was 74.8% (77/103).

CONCLUSIONS

Our prospective postmarket study confirms that PED treatment of aneurysms in a heterogeneous patient population is safe with low rates of neurological morbidity and mortality. Patients with angiographic follow-up had complete occlusion rates of 75% at 8 months.

Outcome of Surgical or Endovascular Treatment of Giant Intracranial Aneurysms, with Emphasis on Age, Aneurysm Location, and Unruptured Aneuryms - A Systematic Review and Meta-Analysis

Background: Designing treatment strategies for unruptured giant intracranial aneurysms (GIA) is difficult as evidence of large clinical trials is lacking. We examined the outcome following surgical or endovascular GIA treatment focusing on patient age, GIA location and unruptured GIA. Methods: Medline and Embase were searched for studies reporting on GIA treatment outcome published after January 2000. We calculated the proportion of good outcome (PGO) for all included GIA and for unruptured GIA by meta-analysis using a random effects model. Results: We included 54 studies containing 64 study populations with 1,269 GIA at a median follow-up time (FU-T) of 26.4 months (95% CI 10.8-42.0). PGO was 80.9% (77.4-84.4) in the analysis of all GIA compared to 81.2% (75.3-86.1) in the separate analysis of unruptured GIA. For each year added to patient age, PGO decreased by 0.8%, both for all GIA and unruptured GIA. For all GIA, surgical treatment resulted in a PGO of 80.3% (95% CI 76.0-84.6) compared to 84.2% (78.5-89.8, p = 0.27) after endovascular treatment. In unruptured GIA, PGO was 79.7% (95% CI 71.5-87.8) after surgical treatment and 84.9% (79.1-90.7, p = 0.54) after endovascular treatment. PGO was lower in high quality studies and in studies presenting aggregate instead of individual patient data. In unruptured GIA, the OR for good treatment outcome was 5.2 (95% CI 2.0-13.0) at the internal carotid artery compared to 0.1 (0.1-0.3, p < 0.1) in the posterior circulation. Patient sex, FU-T and prevalence of ruptured GIA were not associated with PGO. Conclusions: We found that the chances of good outcome after surgical or endovascular GIA treatment mainly depend on patient age and aneurysm location rather than on the type of treatment conducted. Our analysis may inform future research on GIA.

Surgical distal outflow occlusion for the treatment of complex intracranial aneurysms: experience with 18 cases

BACKGROUND

Selected intracranial aneurysms still require parent artery occlusion. Although such occlusion is usually performed proximal to the aneurysm, in rare instances, it may be difficult or impossible to access the proximal parent artery.

OBJECTIVE

To describe the use of parent artery sacrifice distal to the aneurysm (distal outflow occlusion) in the management of complex aneurysms not amenable to standard microsurgical or endovascular therapy.

METHODS

We reviewed a comprehensive database of intracranial aneurysms evaluated between 1997 and 2013. Hospital records, neuroimaging studies, operative reports, and outpatient clinic notes were examined for all patients treated with distal outflow occlusion.

RESULTS

Eighteen patients (11 women, 7 men; ages 28-69 years) underwent surgical distal outflow occlusion. Eight (44%) underwent concomitant distal revascularization. Intraoperative and delayed postoperative angiography was performed in every case. Nine presented with acute subarachnoid hemorrhage, 1 had a remote bleeding episode. The remaining lesions were unruptured; 3 were discovered incidentally, 3 had symptomatic cerebral edema, 1 had transient ischemic attacks, and 1 had cranial neuropathy. The average follow-up period was 6.5 years; no patient was lost to follow-up review. Two aneurysms required delayed endovascular treatment. Overall, 16 patients achieved a good outcome, 1 had moderate disability, and 1 died.

CONCLUSION

We describe our experience with distal outflow occlusion in the treatment of complex aneurysms not amenable to primary clip reconstruction or endovascular therapy. This technique has been described in very limited fashion in the past and may be particularly useful for patients requiring parent artery occlusion when proximal occlusion is challenging or impossible.

Bilateral Cavernous Carotid Aneurysms: The Growth Potential of a Contralateral Aneurysm after Therapeutic Unilateral Internal Carotid Artery Occlusion

BACKGROUND

Although the introduction of flow-diverter stents has been recognized as a major revolution in the treatment of cavernous carotid aneurysms (CCAs), therapeutic internal carotid artery occlusion (TICAO) remains a reliable procedure for alleviating symptoms caused by CCAs. However, TICAO has the potential risk of the enlargement of coexisting aneurysms that are frequently detected in CCA patients. The purpose of this study is to assess the occurrence of the enlargement of aneurysms coexisting with CCAs after TICAO.

METHODS

We reviewed medical charts of CCA patients who were managed using unilateral TICAO. Coexisting aneurysms were identified using angiograms obtained before TICAO, and imaging data in long follow-up periods were retrospectively examined to determine the extent of the enlargement after TICAO.

RESULTS

Of 12 patients with CCAs, 10 had 12 coexisting aneurysms; 5 of the coexisting aneurysms (41.7%) showed enlargement during a mean follow-up period of 8.1 years, and all enlarged aneurysms were smaller of the bilateral CCAs; the larger CCA had been managed by TICAO. Five of 6 (83.3%) patients with bilateral CCAs showed enlargement of the contralateral aneurysm after TICAO. Two contralateral CCAs showed marked enlargement after TICAO and were subsequently treated with stent-assisted coil embolization.

CONCLUSIONS

Contralateral, smaller aneurysms frequently enlarge after unilateral TICAO in patients with bilateral CCAs. The findings emphasize the importance of long-term observation after TICAO and appropriate interventions against enlarging contralateral aneurysms.

Parent artery occlusion in large, giant, or fusiform aneurysms of the carotid siphon: clinical and imaging results

BACKGROUND AND PURPOSE

Parent artery occlusion has long been considered the reference treatment for large/giant or fusiform aneurysms of the carotid siphon. However, meager recent data exist on this technique, which tends to be replaced by stent-assisted reconstructive techniques. In our department since 2004, we have assessed the safety, efficacy, and complication risk factors of parent artery occlusion by using coils for trapping these aneurysms.

MATERIALS AND METHODS

We determined retrospectively the complication rate, factors associated with the occurrence of an ischemic event, changes in symptoms of mass effect, evolution of the aneurysmal size, and the growth of an additional aneurysm after treatment.

RESULTS

Fifty-six consecutive patients were included, with a median age of 54 years (range, 25-85 years; 92% women), 48% with giant aneurysms and 75% with infraclinoid aneurysms. There was a permanent morbidity rate of 5% exclusively due to ischemia, a zero mortality rate, an aneurysmal retraction rate of 91%, and an improvement rate for pain of 98% and for cranial nerve palsy of 72%, with a median follow-up of >3 years. Para-/supraclinoid topography of the aneurysm (P = .043) and the presence of cardiovascular risk factors (P = .024) were associated with an excessive risk of an ischemic event, whereas the presence of a mural thrombus had a protective role (P = .033).

CONCLUSIONS

In this study, parent artery occlusion by using coils to treat large/giant or fusiform aneurysms of the carotid siphon was safe and effective, especially for giant infraclinoid aneurysms. According to recent meta-analyses, these results suggest that the validation of stent-assisted reconstructive treatments for these aneurysms requires controlled studies with parent occlusion artery.

Technical failure of giant supraclinoid aneurysm after internal carotid artery occlusion. A report of three cases

We describe three cases of technical failure in patients with giant supraclinoid aneurysm treated with internal carotid artery (ICA) occlusion. Case 1 was a 65-year-old woman who presented with a two-month history of headache accompanied by blurred vision of the left eye. Case 2 was a 43-year-old woman who presented with a six-month history of headache accompanied by blurred vision of the right eye. Case 3 was a 21-year-old man admitted due to headache and blurred vision of the left eye, accompanied by left oculomotor nerve palsy for three months. Cerebral angiography revealed giant supraclinoid aneurysms in these patients. All of them were treated with ICA occlusion. One case had recurrent headache symptoms after the first procedure and was retreated. Two cases suffered from post-procedural intracranial hemorrhagic complications. Before ICA occlusion for giant supraclinoid aneurysm, balloon occlusion test was used to evaluate the collateral anastomosis between the external carotid artery (ECA) and the ICA, and still plays an important role in preventing treatment failure.

Technical Failure of Giant Supraclinoid Aneurysm after Internal Carotid Artery Occlusion

We describe three cases of technical failure in patients with giant supraclinoid aneurysm treated with internal carotid artery (ICA) occlusion.

Case 1 was a 65-year-old woman who presented with a two-month history of headache accompanied by blurred vision of the left eye. Case 2 was a 43-year-old woman who presented with a six-month history of headache accompanied by blurred vision of the right eye. Case 3 was a 21-year-old man admitted due to headache and blurred vision of the left eye, accompanied by left oculomotor nerve palsy for three months. Cerebral angiography revealed giant supraclinoid aneurysms in these patients. All of them were treated with ICA occlusion.

One case had recurrent headache symptoms after the first procedure and was retreated. Two cases suffered from post-procedural intracranial hemorrhagic complications.

Before ICA occlusion for giant supraclinoid aneurysm, balloon occlusion test was used to evaluate the collateral anastomosis between the external carotid artery (ECA) and the ICA, and still plays an important role in preventing treatment failure.

Balloons in endovascular neurosurgery: history and current applications

The use of balloons in the field of neurosurgery is currently an essential part of our clinical practice. The field has evolved over the last 40 years since Serbinenko used balloons to test the feasibility of occluding cervical vessels for intracranial pathologies. Since that time, indications have expanded to include sacrificing cervical and intracranial vessels with detachable balloons, supporting the coil mass in wide-necked aneurysms (balloon remodeling technique), and performing intracranial and cervical angioplasty for atherosclerotic disease, as well as an adjunct to treat arteriovenous malformations. With the rapid expansion of endovascular technologies, it appears that the indications and uses for balloons will continue to expand. In this article, we review the history of balloons, the initial applications, the types of balloons available, and the current applications available for endovascular neurosurgeons.

Flow diversion versus traditional endovascular coiling therapy: design of the prospective LARGE aneurysm randomized trial

BACKGROUND AND PURPOSE

The goal of aneurysm treatment is occlusion of an aneurysm without morbidity or mortality. Using well-established, traditional endovascular techniques, this is generally achievable with a high level of safety and efficacy. These techniques involve either constructive treatment of the aneurysm (coils with or without an intravascular stent) or deconstruction (coil occlusion) of the aneurysm and the parent artery. While established as safe and efficacious, the constructive treatment of large and giant aneurysms with coils has typically been associated with relatively lower rates of complete occlusion and higher rates of recurrence. Parent artery deconstruction, though immediately efficacious in achieving complete and durable occlusion, does require occlusion of a major intracranial blood vessel and is associated with risk of stroke.

MATERIALS AND METHODS

Flow diversion represents a new technology that can be used to constructively treat large and giant aneurysms. Once excluded successfully, the vessel reconstruction and aneurysm occlusion appears durable. The ability to definitively reconstruct cerebral blood vessels is an attractive approach to these large and giant complex aneurysms and allows the treatment of some aneurysms which were previously not amenable to other therapies. By comparison, conventional coiling techniques have traditionally been used for endovascular treatment of large aneurysms. Large and giant aneurysms that are amenable to either flow diversion or traditional endovascular treatment will be randomized to either therapy with FDA (or appropriate regulatory body) approved devices.

RESULTS

The trial is currently enrolling and results of the data are pending the completion of enrollment and follow-up.

CONCLUSIONS

This paper details the trial design of the LARGE trial, a blinded, prospective randomized trial of large anterior circulation aneurysms amenable to either traditional endovascular treatments using coils or reconstruction with flow diverters.

Evolution of management strategies for cavernous carotid aneurysms: a review

OBJECTIVE

Cavernous carotid aneurysms are considered benign lesions with indolent natural history. Apart from idiopathic aneurysms, traumatic, iatrogenic, and mycotic aneurysms are common in the cavernous segment of the carotid artery. With rapid advances in endovascular therapy, management of cavernous carotid aneurysms has evolved. Our aim was to review the management options available for cavernous carotid aneurysms.

METHODS

The English literature was searched for various studies describing the management of cavernous carotid aneurysms and the evolution of various treatments was studied.

RESULTS

Numerous treatment options are available such as conservative management, Hunterian ligation, surgical clipping, and endovascular therapy. The introduction of flow-diverting stents has revolutionized the management of these lesions. The evolution of various treatment strategies are described.

CONCLUSIONS

A thorough knowledge of all the options is paramount to individualize therapy. We discuss the indications of treatment, various management options for cavernous carotid aneurysms and their outcomes.

Parent artery occlusion for unruptured cerebral aneurysms: the Japanese Registry of Neuroendovascular Therapy (JR-NET) 1 and 2

Parent artery occlusion (PAO) is an alternative to surgical clipping or endovascular endosaccular coil embolization for the management of cerebral aneurysms. Most giant and fusiform aneurysms are not amenable to endosaccular coil embolization due to anatomical considerations, such as a broad-neck. However, majority of reports regarding the safety of PAO are based on case series involving a relatively small number of patients. In the present study, a total of 381 consecutive patients with unruptured cerebral aneurysms who were treated with PAO were extracted from the Japanese Registry of Neuroendovascular Therapy (JR-NET) 1 and JR-NET2 database, which are nationwide surveys conducted by the Japanese Society of Neuroendovascular Therapy. The mean age of the 381 patients was 58.1 years, and 59.3% were female. The aneurysmal location included the vertebral artery (42%) and the cavernous portion of internal carotid artery (32%). The aneurysm size and shape consisted of fusiform (45%), giant (25%), and large (22%). Symptomatic lesions were present in 59.8% of the population. Technical success was achieved in 98.4%. The 30-day morbidity and mortality rates were 3.1% and 1.0%, respectively. The most frequent procedure-related complication was ischemic stroke, which occurred in 12.9% (distal embolism, 6.0%; branch occlusion, 3.9%). The 30-day morbidity and mortality rates related to ischemic strokes were 2.1% and 0.3%, respectively. PAO for unruptured aneurysms is feasible with a high technical success rate. Peri-procedural management of ischemic stroke is the key to enhance the safety of this treatment option.

Occlusion of M1 segment after superficial temporal artery-middle cerebral artery bypass in a giant M1 aneurysm with Onyx-34 injected via a double-lumen balloon under balloon inflation

A 29-year-old patient attended our institution for recurrent strokes related to a giant partially thrombosed M1 aneurysm. Superficial temporal artery-middle cerebral artery (STA-MCA) bypass and subsequent occlusion of both the aneurysm and the dysplastic M1 segment were planned. However, owing to the shortness of the non-dysplastic segment of M1 and the risk of occlusion of the lenticulostriate arteries, the use of a double-lumen balloon was considered for coiling and subsequent injection of Onyx. STA-MCA bypass was performed using a regular technique. Endovascular occlusion of both the aneurysm and the parent artery was subsequently performed by means of coils and Onyx-34 that was injected via the Ascent balloon under balloon inflation. No complications were recorded and no stroke was observed on control MRI. The injection of Onyx-34 through a double-lumen balloon under balloon inflation is a quick and safe technique for precise occlusion of a parent artery.

Occlusion of M1 segment after superficial temporal artery-middle cerebral artery bypass in a giant M1 aneurysm with Onyx-34 injected via a double-lumen balloon under balloon inflation

A 29-year-old patient attended our institution for recurrent strokes related to a giant partially thrombosed M1 aneurysm. Superficial temporal artery-middle cerebral artery (STA-MCA) bypass and subsequent occlusion of both the aneurysm and the dysplastic M1 segment were planned. However, owing to the shortness of the non-dysplastic segment of M1 and the risk of occlusion of the lenticulostriate arteries, the use of a double-lumen balloon was considered for coiling and subsequent injection of Onyx. STA-MCA bypass was performed using a regular technique. Endovascular occlusion of both the aneurysm and the parent artery was subsequently performed by means of coils and Onyx-34 that was injected via the Ascent balloon under balloon inflation. No complications were recorded and no stroke was observed on control MRI. The injection of Onyx-34 through a double-lumen balloon under balloon inflation is a quick and safe technique for precise occlusion of a parent artery.

Visual outcomes for surgical treatment of large and giant carotid ophthalmic segment aneurysms: a case series utilizing retrograde suction decompression (the “Dallas technique”)

Object

The authors report their results in a series of large or giant carotid ophthalmic segment aneurysms clipped using retrograde suction decompression.

Methods

A retrospective review of clinical data and treatment summaries was performed for 18 patients with large or giant carotid artery ophthalmic segment aneurysms managed operatively via retrograde suction decompression. Visual outcomes, Glasgow Outcome Scale (GOS) scores, and operative complications were determined. Postoperative angiography was assessed.

Results

During a 17-year period, 18 patients underwent surgery performed using retrograde suction decompression. The mean aneurysm size was 26 mm. Three patients presented with subarachnoid hemorrhage. Fourteen of 18 patients presented with visual symptoms. Eleven (79%) of these 14 patients experienced visual improvement and the remaining 3 (21%) experienced worsened vision after surgery. Of 3 patients without visual symptoms and a complete visual examination before and after surgery, 1 had visual worsening postoperatively. One aneurysm required trapping and bypass, and all others could be clipped. Postoperative angiography demonstrated complete occlusion in 9 of 17 clipped aneurysms and neck remnants in the other 8 clipped aneurysms. One (5.5%) of 18 patients experienced a stroke. Eighteen patients had a GOS score of 5 (good outcome), and 1 patient had a GOS score of 4 (moderately disabled). There were no deaths. There was no morbidity related to the second incision or decompression procedure. Prolonged improvement did occur, and even in some cases of visual worsening in 1 eye, the overall vision did improve enough to allow driving.

Conclusions

Retrograde suction decompression greatly facilitates surgical clipping for large and giant aneurysms of the ophthalmic segment. Visual preservation and improvement occur in the majority of these cases and is an important outcome measure. Developing endovascular technology must show equivalence or superiority to surgery for this specific outcome.

Long-term clinical and imaging follow-up of complex intracranial aneurysms treated by endovascular parent vessel occlusion

BACKGROUND AND PURPOSE

Flow-diverting stents are increasingly being used for the treatment of complex intracranial aneurysms, but the indications for their use in lieu of traditional endovascular PVO have yet to be precisely defined. The purpose of this study was to review the clinical and imaging outcomes of patients with intracranial aneurysms treated by PVO.

MATERIALS AND METHODS

A total of 28 patients with intracranial aneurysms, treated by PVO between July 1992 and December 2009, were reviewed. Aneurysms arising from peripheral arteries were excluded. Clinical and imaging data were retrospectively analyzed from a prospectively maintained data base.

RESULTS

There were 28 patients with 28 aneurysms treated by PVO. Aneurysms of the anterior circulation presenting with mass effect (n = 11) or discovered incidentally (n = 1), and dissecting-type VB aneurysms presenting with subarachnoid hemorrhage (n = 6) faired the best with high obliteration rates (83.3% and 83.6%, respectively) and no permanent major ischemic complications. In contrast, VB aneurysms presenting with mass effect (n = 7) demonstrated the lowest obliteration rate (57.1%), the highest rate of permanent major ischemic complications (28.6%), and a high mortality rate (28.6%).

CONCLUSIONS

PVO is a safe and effective treatment for complex intracranial aneurysms of the carotid artery and dissecting-type VB aneurysms presenting with SAH. In contrast, PVO for aneurysms of the VB circulation presenting with mass effect is less efficacious and associated with significant morbidity and mortality. It is hoped that flow diverters may represent a better treatment technique for these most difficult-to-treat lesions.

Pipeline embolization device in aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The PED is an FDS designed for the treatment of intracranial aneurysms. Data regarding the use of this device in acute or subacute aSAH is limited to a few case reports or small series. We aimed to demonstrate the feasibility of using an FDS, the PED, for the treatment of ruptured intracranial aneurysms with challenging morphologies.

MATERIALS AND METHODS

We conducted a retrospective review of all known patients treated with the PED for aSAH at 4 institutions between June 2008 and January 2012. Pertinent clinical and radiologic information was submitted by individual centers for central collation. The decision to treat with the PED was made on a case-by-case basis by a multidisciplinary team under compassionate use.

RESULTS

Twenty patients (15 women; median age, 54.5 years; IQR, 8.0 years) were found. There were 8 blister, 8 dissecting or dysplastic, 2 saccular, and 2 giant aneurysms. Median time to treatment was 4 days (range, 1-90 days; IQR, 12.75 days) from rupture. Three patients had previous failed treatment. Procedure-related symptomatic morbidity and mortality were 15%, with 1 (5%) procedure-related death. Two patients died relative to medical complications, and 1 patient was lost to follow-up. Sixteen patients were available for follow-up, 81% had a GOS of 5, and 13% had a GOS of 4 attributed to a poorer initial clinical presentation. One patient died of urosepsis at 4 months. Occlusion rates were 75% and 94% at 6 months and 12 months, respectively. There were 3 delayed complications (1 silent perforator infarct, 2 moderate asymptomatic in-stent stenoses). No symptomatic delayed complications or rehemorrhages occurred.

CONCLUSIONS

The FDS may be a feasible treatment option in the acute or subacute setting of selected ruptured aneurysms, especially blister aneurysms. Ruptured giant aneurysms remain challenging for both surgical and endovascular techniques; at this stage, FDSs should be used with caution in this aneurysm subtype.

Giant extracranial aneurysm of the internal carotid artery in neurofibromatosis type 1. A case report and review of the literature

Neurofibromatosis type 1 (NF-1) is an autosomal dominant disorder characterized by cutaneous pigmentations, neurofibromas, Lisch nodules and neuroectodermal tumors. Supra-aortic vessel aneurysms may affect patients with NF-1 and can be associated with rupture, ischemic complications and compression symptoms. We describe a 48-year-old woman with NF-1 and an extracranial 3×5 cm right internal carotid artery aneurysm. After balloon test occlusion the patient was treated with parent artery sacrifice which led to significant shrinkage on follow-up MR and reduction of compression symptoms. The literature concerning internal carotid artery aneurysms associated with NF-1 is reviewed evaluating the possible therapeutic options.

Treatment of intracranial aneurysms using the pipeline flow-diverter embolization device: a single-center experience with long-term follow-up results

BACKGROUND AND PURPOSE

Flow-diverting devices now offer a new treatment alternative for cerebral aneurysms. We present the results of a large single-center series of patients treated with the PED, including long-term follow-up.

MATERIALS AND METHODS

Between November 2008 and September 2011, sidewall aneurysms with a wide neck (≥4 mm) or unfavorable dome-neck ratio (≤1.5); large/giant, fusiform, dissecting, blister-like, and recurrent sidewall aneurysms; aneurysms at difficult angles; and aneurysms in which a branch was originating directly from the sac were treated with the PED. Patients were premedicated with dual antiplatelet medications. Data, including demographics, aneurysm features, clinical presentation, complications, results, and follow-up information, for up to 2 years are presented.

RESULTS

Two hundred fifty-one aneurysms in 191 patients were treated. Of these, 96 (38.3%) were large or giant (≥10 mm). In 34/251 (13.5%), PEDs were used for retreatment. Adjunctive coiling was performed in 11 aneurysms (2.1%). The mean number of devices per aneurysm was 1.3. One aneurysm ruptured in the fourth month posttreatment (0.5%), and symptomatic in-construct stenosis was detected in 1 patient (0.5%) treated with percutaneous transarterial angioplasty. Any event rate was 27/191 (14.1%), with a permanent morbidity of 1% and mortality of 0.5%. Control angiography was available in 182 (95.3%) patients with 239 (95.2%) aneurysms. In 121 aneurysms (48.2%), 1- to 2-year control angiography was available. The aneurysm occlusion rate was 91.2% in 6 months, increasing to 94.6%.

CONCLUSIONS

Use of the PED is safe, efficacious, and durable in cerebral aneurysm treatment, with low morbidity-mortality and high occlusion rates as confirmed with mid- to long-term control angiography.

Flow-diverter silk stent for the treatment of intracranial aneurysms: 1-year follow-up in a multicenter study

BACKGROUND AND PURPOSE

FD stent placement is a promising therapy for challenging intracranial aneurysms. Long-term evaluations about angiographic and morphologic results are still missing. This is the aim of this multicenter series.

MATERIALS AND METHODS

We report our experience and 1-year FU in a retrospective chart review of 65 consecutive subjects with 77 unruptured or recanalized aneurysms that were treated with Silk FD stents at 6 centers in France. Both angiographic and clinical results were recorded before treatment and at 6 and 12 months after treatment. At the 12-month FU, relationships between angiographic aneurysm occlusion and shrinkage of the thrombosed aneurysm sac were evaluated.

RESULTS

Stent deployment was achieved in 64 cases (98.5%) and failed in 1 case (1.5%). Seven misdeployments of the Silk stent caused the occlusion of 6 parent arteries. Overall acute/subacute procedural morbidity was 7.7%, and mortality was zero. Delayed complications were observed in 10.9% of subjects. At the 6-month FU, permanent morbidity was 7.8% and mortality was 3%. Complete occlusion occurred within 6 months in 68% of aneurysms and within 12 months after treatment in 84.5% of aneurysms. At the 12-month FU, in angiographically complete occluded aneurysms, MR imaging/CT analysis showed the complete disappearance of the thrombosed aneurysm in 30% of cases and partial shrinkage in 52%; furthermore, thrombosed aneurysms were stable in 11% of cases and enlarged in 7%.

CONCLUSIONS

The Silk stent is an effective tool for the treatment of challenging aneurysms because it allows complete occlusion in most cases 1 year after treatment. Permanent morbidity was 7.8%, and mortality was 3%.