M. Sluzewski

Coiling of Intracranial Aneurysms A Systematic Review on Initial Occlusion and Reopening and Retreatment Rates

Background and Purpose— The proportion of incompletely occluded aneurysms after coiling varies widely between studies. To assess overall outcome of coiling, we systematically reviewed the literature to determine initial occlusion, reopening, and retreatment rates of coiled aneurysms according to predefined criteria and subgroups. Methods— We searched PubMed and EMBASE (January 1999 to September 2008) for studies of >50 coiled aneurysms. Two reviewers independently extracted data. We grouped studies reporting on only ruptured aneurysms, posterior circulation aneurysms, and studies with large proportions of aneurysms >10 mm to assess possible determinants for incomplete occlusion, reopening, and retreatment. Results— Forty-six studies totalling 8161 coiled aneurysms met inclusion criteria. Immediately after coiling, 91.2% (95% CI, 90.6% to 91.9%) of the aneurysms were adequately occluded. Aneurysm reopening occurred in 20.8% (95% CI, 19.8% to 21.9%) and retreatment was performed in 10.3% (95% CI, 9.5% to 11.0%). Reopening rate was lower in studies reporting on ruptured aneurysms only compared with all studies (11.4% versus 20.8%; relative risk, 0.55; 95% CI, 0.47 to 0.64) and higher in studies focusing on posterior circulation aneurysms compared with studies with >85% anterior circulation aneurysms (22.5% versus 15.5%; relative risk, 1.5; 95% CI,1.2 to 1.7). Regression analysis showed higher retreatment rates with increasing proportion of aneurysms >10 mm (β=0.252; 95% CI, 0.073 to 0.432). We could not find a relation between reopening and type of coils used. Conclusion— At follow-up, one fifth of all coiled intracranial aneurysms shows reopening of which half is retreated. Possible risk factors for aneurysm reopening are location in the posterior circulation and size >10 mm. To confirm our findings, a meta-analysis on individual well-reported patient data is desirable. # Supplemental Appendix {#article-title-2}Background and Purpose— The proportion of incompletely occluded aneurysms after coiling varies widely between studies. To assess overall outcome of coiling, we systematically reviewed the literature to determine initial occlusion, reopening, and retreatment rates of coiled aneurysms according to predefined criteria and subgroups. Methods— We searched PubMed and EMBASE (January 1999 to September 2008) for studies of >50 coiled aneurysms. Two reviewers independently extracted data. We grouped studies reporting on only ruptured aneurysms, posterior circulation aneurysms, and studies with large proportions of aneurysms >10 mm to assess possible determinants for incomplete occlusion, reopening, and retreatment. Results— Forty-six studies totalling 8161 coiled aneurysms met inclusion criteria. Immediately after coiling, 91.2% (95% CI, 90.6% to 91.9%) of the aneurysms were adequately occluded. Aneurysm reopening occurred in 20.8% (95% CI, 19.8% to 21.9%) and retreatment was performed in 10.3% (95% CI, 9.5% to 11.0%). Reopening rate was lower in studies reporting on ruptured aneurysms only compared with all studies (11.4% versus 20.8%; relative risk, 0.55; 95% CI, 0.47 to 0.64) and higher in studies focusing on posterior circulation aneurysms compared with studies with >85% anterior circulation aneurysms (22.5% versus 15.5%; relative risk, 1.5; 95% CI,1.2 to 1.7). Regression analysis showed higher retreatment rates with increasing proportion of aneurysms >10 mm (&bgr;=0.252; 95% CI, 0.073 to 0.432). We could not find a relation between reopening and type of coils used. Conclusion— At follow-up, one fifth of all coiled intracranial aneurysms shows reopening of which half is retreated. Possible risk factors for aneurysm reopening are location in the posterior circulation and size >10 mm. To confirm our findings, a meta-analysis on individual well-reported patient data is desirable.

3D Rotational Angiography: The New Gold Standard in the Detection of Additional Intracranial Aneurysms

BACKGROUND AND PURPOSE: During surgery of symptomatic aneurysms, additional small angiographic occult aneurysms are commonly found. With 3D rotational angiography (3DRA) small aneurysms are more easily depicted than with digital subtraction angiography (DSA). In this study we compare 3DRA with DSA in the depiction of small additional aneurysms. MATERIALS AND METHODS: Three hundred fifty 3D datasets of 1 vascular tree of 350 patients with at least 1 intracranial aneurysm on the dataset were re-evaluated for the presence of additional aneurysms by 2 observers in consensus. Two other observers, blinded to the 3D images, re-evaluated DSA images of the same 350 vascular trees for these additional aneurysms. Results were compared. RESULTS: In 350 3D datasets, 350 target aneurysms and 94 additional aneurysms were detected. The mean size of 94 additional aneurysms was 3.54 mm (median, 3; range, 0.5–17 mm). The proportion of aneurysms ≤3 mm was significantly higher in additional aneurysms (61 of 94, 65%) than in the target aneurysms (61 of 350, 17%) (χ2, P < .0001). Of 94 additional aneurysms, 27 (29%) were missed on DSA by both observers. The mean size of the missed aneurysms was 1.94 mm (median, 2; range, 0.5–4 mm). The proportion of aneurysms ≤3 mm in missed additional aneurysms (26 of 27, 96%) was significantly higher than that in all additional aneurysms (61 of 94, 65%) (χ2, P = .0035). The location of missed additional aneurysms was not different from the location of all additional aneurysms. CONCLUSION: 3DRA depicts considerably more small (≤3 mm) additional aneurysms than DSA. In selected patients, accurate detection of these aneurysms may have consequences for the choice of treatment technique and for the frequency and duration of imaging follow-up.

Coiling of Very Large and Giant Basilar Tip Aneurysms: Midterm Clinical and Angiographic Results

BACKGROUND AND PURPOSE: The purpose of this study was to report the midterm clinical and angiographic results of coiling of very large (>15 mm) and giant basilar tip aneurysms. MATERIALS AND METHODS: Between January 1995 and October 2005, 44 very large and giant basilar tip aneurysms in 44 patients were coiled. There were 13 men (30%) and 31 women (70%) with a mean age of 51.4 years (median, 51 years; range, 34–72 years). Mean aneurysm size was 19.6 mm (range, 15–30 mm). Of 44 aneurysms, 33 (75%) had ruptured. Of 11 unruptured basilar tip aneurysms, 7 were incidentally discovered, 1 was additional to another ruptured aneurysm, and 3 were symptomatic by mass effect. RESULTS: Procedural mortality was 2/44 (4.6%, 95% confidence interval (CI), 0.4%–16%) and morbidity 1/44 (2.3%, 95% CI, 0.01%–13%). Of 33 patients with ruptured aneurysms, mean clinical follow-up was 5.2 years (range, 0.5–11.5 years). Two patients had a rebleeding from the coiled basilar tip aneurysm leading to death in 1 patient and to dependency in the other patient (annual rebleeding rate, 1.1%) One other patient died 2 years later of progressive brain stem compression. Mean angiographic follow-up in 41 of 42 surviving patients was 3.1 years. Nineteen aneurysms reopened and were coiled for a second time. Of these, 9 repeatedly reopened with time and were repeatedly coiled up to 6 times. Additional treatments were without complications. CONCLUSION: Coiling of very large and giant basilar tip aneurysms is associated with reasonably low morbidity. Although additional treatment during follow-up is frequently necessary, rebleeding is uncommon.

Quality of life after treatment of unruptured intracranial aneurysms by neurosurgical clipping or by embolisation with coils. A prospective, observational study.

Background: Relatively high rates of complications occur after operation for unruptured intracranial aneurysms. Published data on endovascular treatment suggest lower rates of complications. We measured the impact of treatment of unruptured aneurysms by clipping or coiling on functional health, quality of life, and the level of anxiety and depression. Methods: In three centres, we prospectively collected data on patients with an unruptured aneurysm who were treated by clipping or coiling. Treatment assignment was left to the discretion of the treating physicians. Before, 3 and 12 months after treatment, we used standardised questionnaires to assess functional health (Rankin Scale score), quality of life (SF-36, EuroQol), and the level of anxiety and depression (Hospital Anxiety and Depression Scale). Results: Nineteen patients were treated by coiling and 32 by clipping. In the surgical group, 4 patients (12%) had a permanent complication; 36 of all 37 aneurysms (97%) were successfully clipped. Three months after operation, quality of life was worse than before operation; 12 months after operation, it had improved but had not completely returned to baseline levels. Scores for depression were higher than in the general population. In the endovascular group, no complications with permanent deficits occurred; 16 of 19 aneurysms (84%) were occluded by more than 90%. One patient died from rupture of the previously coiled aneurysm. In the others, quality of life after 3 months and after 1 year was similar to that before treatment. Conclusions: In the short term, operation of patients with an unruptured aneurysm has a considerable impact on functional health and quality of life. After 1 year, recovery occurs but it is incomplete. Coil embolisation does not affect functional health and quality of life.

Clinical and Angiographic Results of Coiling of 196 Very Small (≤ 3 mm) Intracranial Aneurysms

BACKGROUND AND PURPOSE: Coiling of very small (≤ 3 mm) aneurysms is considered controversial because of technical difficulties and a higher rate of procedural aneurysm ruptures. In this study, we report clinical and angiographic results of coiling of aneurysms 3 mm or smaller in comparison with larger aneurysms in a large, single-center cohort of patients. MATERIALS AND METHODS: Between 1995 and July 2008, a total of 1295 aneurysms were selectively occluded with coils. Of 1295 aneurysms, 196 (15.1%) in 187 patients were very small. Of 196 aneurysms, 149 (76%) had ruptured and 47 (24%) had not ruptured. There were 51 males (27%) and 136 females (73%). Mean age was 54.7 years (age range, 11–78 years). RESULTS: Procedural morbidity rate was 2.1% and mortality rate, 1.1%. Procedural rupture occurred in 15 of 196 aneurysms (7.7%). In 13 of 15 procedural ruptures, this had no adverse effect on outcome. Early recurrent hemorrhage of the coiled aneurysm occurred in 2 patients (1.1%). Compared with larger aneurysms, in very small aneurysms more often a procedural rupture occurred (7.7% versus 3.6%; P = .018). Procedural morbidity rate was lower (3.2% versus 5.5%), but this was not significant (P = .26). Retreatment rate consisted predominantly of clipping soon after incomplete coiling and was lower than in larger aneurysms (5.1% versus 10.0%; P = .041). Other characteristics were not significantly different. CONCLUSIONS: Coiling of very small aneurysms was technically feasible, with good results. Although procedural aneurysm rupture was significantly more frequent in very small aneurysms, this did not lead to increased overall morbidity and mortality rates. Retreatment rate was lower than for larger aneurysms.

Perforator Infarction after Placement of a Pipeline Flow-Diverting Stent for an Unruptured A1 Aneurysm

Flow-diverting stents such as the Pipeline embolization device (PED; ev3, Irvine, California) or Silk (Balt, Montmorency, France) were recently introduced in clinical practice for the treatment of fusiform and wide-neck intracranial aneurysms. These stents are designed to divert the flow in the parent artery, with reduction of inflow in the aneurysm leading to thrombosis. The devices have 30%–35% metal surface-area coverage (as opposed to approximately 10% for conventional intracranial stents) to promote flow diversion and, at the same time, to keep open branch vessels and perforating arteries that are crossedbythedevice.Althoughthese2requiredpropertiesseemcontradictory, the first clinical results are promising in terms of both effectiveness and safety. 1 Recently, we treated a 68-year-old woman with an incidentally discovered large dumbbell aneurysm located on the left A1 segment (Fig 1A ,- B) with a PED. Because the first PED that was placed shortened more than we expected, it did not completely cover the neck of the aneurysm, and a second PED was placed telescopically with overlap on the aneurysm neck only and with some protrusion in the middle cerebral artery (Fig 1C). Immediately after the procedure, the patient appeared apathetic and hemiparetic on the right side. MR diffusion imaging showed infarction in the left basal ganglia in the territories of the lenticulostriate arteries arising from the A1 segment

Endovascular Treatment of Symptomatic Intradural Vertebral Dissecting Aneurysms

BACKGROUND AND PURPOSE: The purpose of this study was to report our experience with endovascular treatment of 14 patients with symptomatic intradural vertebral dissecting aneurysms. Materials AND METHODS: Between January 2000 and January 2006, 14 patients with symptomatic intradural dissecting vertebral aneurysms were treated. A total of 756 (568 ruptured, 188 unruptured) endovascular treated aneurysms (incidence, 1.9%) were treated during this period. There were 7 female and 7 male patients with a mean age of 48 years (age range, 10–64 years). Thirteen patients (93%) presented with subarachnoid hemorrhage (SAH) and 1 (7%) presented with acute symptoms of mass effect on the brain stem. RESULTS: Treatment consisted of coil occlusion of the dissected arterial segment including the aneurysm (internal coil trapping) in 13 of 14 patients and stent placement over the aneurysm as the only therapy in 1 patient. All aneurysms and occluded arterial segments remained occluded on follow-up imaging at 6 to 13 months, and none of the patients had infarctions in the medulla or territory of the posterior inferior cerebellar artery. Clinical outcome was excellent in 11 patients; 3 had cognitive impairment after SAH but were independent in daily activities. There were no episodes of recurrent hemorrhage. CONCLUSION: Intradural vertebral dissecting aneurysms presenting with SAH should be treated promptly because of the high risk of recurrent hemorrhage. In our experience, trapping of the dissected segment with coils was straightforward, could be done in most patients, and was effective in preventing rebleeding. In our opinion, only in exceptional circumstances are more sophisticated techniques aimed at preservation of the parent artery necessary.

A New Self-Expandable Nitinol Stent for the Treatment of Wide-Neck Aneurysms: Initial Clinical Experience

BACKGROUND AND PURPOSE: Stent systems for intracranial use are continuously improved. We report our initial experience using a new self-expanding easy-to-place nitinol stent (Enterprise) in the treatment of wide-neck intracranial aneurysms. MATERIALS AND METHODS: Between January and October 2007, 16 aneurysms in 15 patients were treated with stent assistance. Aneurysm size was a mean of 13.2 mm (median, 12 mm; range, 7–30 mm). Eight aneurysms had reopened after prior coiling, and 8 aneurysms were primarily treated, 1 after acute subarachnoid hemorrhage. Response to antiplatelet premedication was tested with a P2Y12 assay before stent placement. On a 3D angiographic workstation, stent placement was simulated to assess vessel caliber and appropriate stent length. RESULTS: In all aneurysms, the stent could be placed at the exact location as predicted from the computer simulation. Stent placement proved to be technically easy without the need for recapture in all patients. Although placement of the microcatheter through the stent struts and subsequent coil placement was challenging in some patients, coiling after stent placement resulted in complete or near-complete occlusion in all aneurysms. There were no technical or clinical complications. At 6 months, angiographic follow-up in 14 aneurysms revealed 4 aneurysms recanalized to 80% occlusion, 3 of which were additionally coiled. CONCLUSION: In this small series, delivery and deployment of the Enterprise stent was technically easy. There were no technical or clinical complications. The device was valuable in the treatment of wide-neck aneurysms. The need for antiplatelet medication in patients treated with this and other stents remains a significant disadvantage.

Complications of Particle Embolization of Meningiomas: Frequency, Risk Factors, and Outcome

BACKGROUND AND PURPOSE: Particle embolization is widely used in the treatment of meningiomas. We assessed the frequency and outcome of complications of embolization of meningiomas and tried to identify risk factors. MATERIALS AND METHODS: Between 1994 and 2009, a total of 198 patients with 201 meningiomas underwent embolization. Indication for embolization was preoperative in 165 meningiomas and adjunctive to radiosurgery in 8. In the remaining 28 meningiomas, embolization was initially offered as a sole therapy. There were 128 women and 70 men with a mean age of 54.4 years (median age, 54 years; range, 15–90 years). Complications were defined as any neurologic deficit or death that occurred during or after embolization. Logistic regression was used to identify the following possible risk factors: age above median, female sex, tumor size above median, meningioma location in 5 categories, use of small particle size (45–150 μm), the presence of major peritumoral edema, and arterial supply in 3 categories. RESULTS: Complications occurred in 11 patients (5.6%; 95% confidence interval [CI], 3.0%–9.8%). Ten complications were hemorrhagic, and 1 was ischemic. Six of 10 patients with hemorrhagic complications underwent emergency surgery with removal of the hematoma and meningioma. Complications of embolization resulted in death in 2 and dependency in 5 patients (7/198, 3.5%; 95% CI, 1.6%–2.0%). The use of small particles (45–150 μm) was the only risk factor for complications (odds ratio [OR], 10.21; CI, 1.3–80.7; P = .028). CONCLUSIONS: In this series, particle embolization of meningiomas had a complication rate of 5.6%. We believe that the use of small polyvinyl alcohol (PVA) particles (45–150 μm) should be discouraged.

Endovascular coiling versus neurosurgical clipping in patients with a ruptured basilar tip aneurysm

Objectives: To compare endovascular coiling with neurosurgical clipping of ruptured basilar bifurcation aneurysms. Methods: Patient and aneurysm characteristics, procedural complications, and clinical and anatomical results were compared retrospectively in 44 coiled patients and 44 patients treated by clipping. The odds ratios for poor outcome (Glasgow outcome scale 1, 2, 3) adjusted for age, clinical condition, and aneurysm size were assessed by logistic regression analysis. Results: In the endovascular group, five patients (11%) had a poor outcome v 13 (30%) in the surgical group; the adjusted odds ratio for poor outcome after coiling v clipping was 0.28 (95% confidence interval, 0.08 to 0.99). Procedural complications were more common in the surgical group. Optimal or suboptimal occlusion of the aneurysm immediately after coiling was achieved in 41 patients (93%). Clipping was successful in 40 patients (91%). Conclusions: The results suggest that embolisation with coils is the preferred treatment for patients with ruptured basilar bifurcation aneurysms.