Henry Moyle

An update to the Raymond–Roy Occlusion Classification of intracranial aneurysms treated with coil embolization

Background The Raymond–Roy Occlusion Classification (RROC) is the standard for evaluating coiled aneurysms (Class I: complete obliteration; Class II: residual neck; Class III: residual aneurysm), but not all Class III aneurysms behave the same over time. Methods This is a retrospective review of 370 patients with 390 intracranial aneurysms treated with coil embolization. A Modified Raymond–Roy Classification (MRRC), in which Class IIIa designates contrast within the coil interstices and Class IIIb contrast along the aneurysm wall, was applied retrospectively. Results Class IIIa aneurysms were more likely to improve to Class I or II than Class IIIb aneurysms (83.34% vs 14.89%, p<0.001) and were also more likely than Class II to improve to Class I (52.78% vs 16.90%, p<0.001). Class IIIb aneurysms were more likely to remain incompletely occluded than Class IIIa aneurysms (85.11% vs 16.67%, p<0.001). Class IIIb aneurysms were larger with wider necks while Class IIIa aneurysms had higher packing density. Class IIIb aneurysms had a higher retreatment rate (33.87% vs 6.54%, p<0.001) and a trend toward higher subsequent rupture rate (3.23% vs 0.00%, p=0.068). Conclusions We propose the MRRC to further differentiate Class III aneurysms into those likely to progress to complete occlusion and those likely to remain incompletely occluded or to worsen. The MRRC has the potential to expand the definition of adequate coil embolization, possibly decrease procedural risk, and help endovascular neurosurgeons predict which patients need closer angiographic follow-up. These findings need to be validated in a prospective study with independent blinded angiographic grading.

Initial experience with Penumbra Coil 400 versus standard coils in embolization of cerebral aneurysms: a retrospective review

Background and purpose The Penumbra Coil 400 System (PC 400) is the newly introduced platinum coil system designed specifically to enhance filling efficiency by increasing coil diameter. Our goal was to study the packing and treatment advantage of the PC 400s unique geometric configuration compared with conventional coils (controls). Materials and methods 16 aneurysms embolized with the PC 400 in 2011 were compared with 79 equally matched aneurysms embolized with conventional coils from 2004 to 2011. Primary outcomes assessed were acute packing density, embolization time, and the number of coils required for aneurysm occlusion. Results Aneurysm embolization with the PC 400 achieved a higher packing density (36.8% vs 28.1%; p<0.005) and with fewer coils (an average of 3.9 vs 6.1 coils per aneurysm; p<0.05). In addition, the total procedural time for the subjects treated with the PC 400 was significantly less (45.7 vs 64.1 min; p<0.05). There were no procedural complications associated with the PC 400. Conclusions Compared with conventional coils, the PC 400 is more efficient in the embolization of cerebral aneurysms, achieving greater packing density with fewer coils and less time without compromising safety.

Analysis of early angiographic outcome using unique large diameter coils in comparison with standard coils in the embolization of cerebral aneurysms: a retrospective review

Background The initial experience with the large diameter Penumbra Coil 400 (PC400) system has been positive regarding safety, efficacy, improved packing density and cost effectiveness, but follow-up data are limited. Methods This is a single-center retrospective review of 76 aneurysms treated with PC400 coils compared with 301 aneurysms treated with a variety of different bare platinum and bioactively coated coils. Atypical and giant aneurysms were excluded as well as those that had undergone previous treatment. Occlusion classification was determined immediately after the procedure and at short-term follow-up. Results Compared with controls, in the PC400 group fewer coils were used (3.53 vs 5.44, p<0.05), procedure time was decreased (48 vs 64 min, p<0.05) and packing density was increased (31.7% vs 24.8%, p<0.05). There were more grade III aneurysms (71.1% vs 38.2%, p<0.05) and fewer grade I aneurysms (13.2% vs 30.2%, p<0.05) in the PC400 group than in the control group immediately after the procedure. At first follow-up, however, more aneurysms in the PC400 group improved (51.3% vs 28.7%, p<0.05) in angiographic grade leading to similar rates of acceptable outcome (grades I or II) at first follow-up (PC400 79.5% vs control 77.2%). The adverse event rate was similar in the two groups. Conclusions Large diameter PC400 coils can be used to safely treat cerebral aneurysms with fewer coils, decreased procedure time and increased packing density compared with standard coils. The early angiographic outcome is similar to that achieved with standard coils.

Predictors of treatment failure following coil embolization of intracranial aneurysms

We present a retrospective review of 357 consecutive patients with 419 aneurysms treated with coil embolization. Although incomplete occlusion and recurrence of intracranial aneurysms following coil embolization is a well-known problem, the factors that influence and predict treatment failure are still debated. For this study, we excluded non-coiling endovascular techniques (flow diversion) and non-saccular aneurysms (fusiform). The modified Raymond-Roy occlusion classification (MRRC) was used to grade the aneurysms. Treatment failure was defined as filling of the aneurysm dome (MRRC Class IIIa or IIIb) at the first angiographic follow-up (average 8 months). Univariate statistical tests were employed to select variables for incorporation into a multivariable logistic regression model. Multivariate analysis identified greater aneurysm volume (p<0.001), packing density (PD) less than 31% (p=0.007) and initial MRRC Class IIIb (p<0.001) as predictors of treatment failure. Incomplete neck coverage with coils was associated with treatment failure in univariate but not multivariate analysis. Class IIIb status was more predictive of treatment failure compared to all Class III (odds ratio 168 versus 14.4). Clinical outcomes were similar in both groups except that there were more retreatments in the treatment failure group (p<0.001). Aneurysm volume, PD and initial occlusion class are associated with angiographic outcome, consistent with prior literature. The MRRC is a powerful predictor of treatment failure. These results will be useful in the effort to both prevent and predict treatment failure after coil embolization, however, they should be verified in a prospective study.

Angiographic outcome of intracranial aneurysms with neck remnant following coil embolization.

Background The degree of aneurysm occlusion following coil embolization has an impact on aneurysm recanalization. Objective To explain the natural history of intracranial aneurysms with neck remnant, Raymond–Roy Occlusion Classification (RROC) class II. Methods A single-center, retrospective study of 198 patients with 209 aneurysms treated with coil embolization that were initially either RROC class I or II. The angiographic outcomes at short- and long-term follow-up were compared as well as the complication/re-treatment rates. Atypical aneurysms and those that had been previously treated were excluded. Results Ninety-nine class I aneurysms were compared with 110 class II aneurysms. There was no difference in recanalization rate between the groups (class I 3.3% vs class II 8.5%, p=0.478) at short-term follow-up (8.2 months) and at subsequent follow-ups (21.7 and 52.1 months). There was also no difference in re-treatment rates (class I 3.3% vs class II 8.5%, p=0.196) or complication rates (class I 9.1% vs class II 4.6%, p=0.12). There were no aneurysm ruptures after treatment in either group. Conclusions The angiographic outcome of aneurysms with neck remnant following coil embolization is similar to that of completely occluded aneurysms in that most remain stable and few recanalize. This understanding could potentially help the interventional neurosurgeon avoid complications such as coil herniation, vessel compromise, and stroke in selected cases. Further investigation with a larger patient population is warranted.

Safety and cost of stent-assisted coiling of unruptured intracranial aneurysms compared with coiling or clipping

Objective Stent-assisted coiling (SAC) of unruptured intracranial aneurysms is a treatment alternative to clipping or coiling, although high complication and procedure-related mortality rates have been reported. Methods A retrospective study was conducted of patients undergoing SAC, coiling or clipping of unruptured intracranial aneurysms between 2003 and 2010. Rates of residual aneurysm, recanalization, complications, cost (adjusted to 2010), length of stay (LOS) and outcome were compared between groups. Results Of 116 subjects, 47 underwent SAC, 33 coiling and 36 clipping. The groups were similar in age, gender and aneurysm location, although the SAC group had significantly larger aneurysms with wider necks (p=0.001). Patients who underwent SAC had more residual aneurysm after initial treatment than those treated with coiling or clipping (75%, 52% and 19%, respectively, p<0.0001), but this difference was smaller at follow-up angiography (50%, 50% and 17% residual, respectively) and was not significant after adjusting for baseline aneurysm and neck size. SAC was not associated with increased recanalization, requirement for additional treatment, mortality or complications after adjusting for aneurysm and neck size. Patients who underwent SAC and those who underwent coiling were more likely to have a good discharge disposition than patients treated with clipping (100% vs 91%, p=0.042). LOS was significantly shorter for patients who underwent SAC or coiling compared with those treated with clipping (p<0.0001). The overall direct cost was higher for patients who underwent SAC than for those treated with coiling or clipping (median

Intracranial Aneurysms: Endovascular Treatment

22 544 vs

E-040 Initial Multi-Centre Experience with the Penumbra PC 400 Detachable Coil

12 933 vs

E-037 Initial Multi-Centre Experience with the Penumbra PC 400 Detachable Coil in aneurysms 10 mm or greater

14 656, p=0.001), even after adjusting for aneurysm and neck size, LOS and retreatment. Conclusions SAC is a safe alternative to coiling or clipping of unruptured aneurysms but it is currently more expensive.

P-033 Aneurysm embolization treatment efficiency: comparing the penumbra coil 400TM system to conventional coils

The incidence of subarachnoid hemorrhage is estimated at 5 to 10 per 100,000 per year. In patients who survive the initial hemorrhage, the repeat hemorrhage rate is 15% to 20% in the first 2 weeks after presentation and is associated with devastating clinical outcomes even graver than the initial rupture. The current options for aneurysm treatment are surgical clipping and, since the mid-1990s, neuroendovascular coil embolization. The former was at one time the gold standard of care, but consistent with the trend in modern medicine toward less-invasive procedures, the latter has steadily gained prominence. Although there is still controversy as to its long-term durability and safety, it is now the preferred procedure. This article describes the procedures antecedents, rationale, and essential components. Mt Sinai J Med 77:279-285, 2010. (c) 2010 Mount Sinai School of Medicine.