The p48 flow diverter: First clinical results in 25 aneurysms in three centers

Abstract

Background The novel low-profile p48 flow diverter has been designed to treat aneurysms on small vessels of 1.75–3mm. We report our first clinical experiences. Methods Between March 2018–January 2020, 22 patients with 25 aneurysms were treated with the p48 in 3 centers. One patient had 3 aneurysms covered by one p48 and one patient had 2 aneurysms. There were 5 men, 17 women, with a mean age of 55 years (median 59, range 29–73 years). Results In 25 aneurysms, 24 p48 flow diverters were placed. In 1 patient additional coils were placed in the aneurysm. Procedural vessel rupture by the micro guidewire occurred in 2 patients and vessel rupture during p48 balloon dilatation occurred in 1 patient. Overall, the permanent morbidity rate was 13.6% (3 of 22, 95%CI 3.9–34.2%) and mortality was 4.5% (1 of 22, 95%CI <0.01–23.5%). Most complications were procedure-related and not device-specific. Of 22 patients with 25 aneurysms treated with p48, 18 patients with 20 aneurysms had angiographic follow-up after 5–18 months. Of 19 aneurysms, 10 were occluded and 7 showed a remnant. Two aneurysms were open after 6 months. Three aneurysms were still not occluded after 12, 14, and 18 months and these 3 were retreated. Retreatment rate was 16% (3 of 19) and the adequate occlusion rate was 90% (17 of 19). Conclusions Treatment of aneurysms in small-caliber vessels with the p48 is feasible and effective but is not without complications. More data is needed to establish indications, safety, and efficacy more accurately.

Patient outcomes after treatment of brain aneurysm in small diameter vessels with the silk vista baby flow diverter: A systematic review

“…The p48 flow diverter (Phenox, Bochum, Germany) is delivered through a 0.021-inch microcatheter and was also designed to be accommodated in small parent vessels, with rates of complete aneurysm occlusion varying from 47.9% to 75% on early angiographic follow-up. [26][27][28] The complications encountered in previous experiences using the device included hemorrhagic and ischemic events, with reported morbidity ranging from 2.5% to 13.6%. [26][27][28] The SVB is a 48 self-expandable, braided construct composed of drawn filled tubes (DFTs) of platinum-filled nitinol, with the latter component contributing to elasticity and shape memory.…”

“…[26][27][28] The complications encountered in previous experiences using the device included hemorrhagic and ischemic events, with reported morbidity ranging from 2.5% to 13.6%. [26][27][28] The SVB is a 48 self-expandable, braided construct composed of drawn filled tubes (DFTs) of platinum-filled nitinol, with the latter component contributing to elasticity and shape memory. 29 The mechanical properties and design of the stent facilitate visualization of the device, navigability, and controlled deployment.…”

“…26–28 The complications encountered in previous experiences using the device included hemorrhagic and ischemic events, with reported morbidity ranging from 2.5% to 13.6%. 26–28…”

Silk Vista Baby Is a Safe and Technically Feasible Flow Diverting Stent for Distal Aneurysm Treatment

“…In Maurer's et al (15) study of 124 treated aneurysms, they reported 0.0% (0/124) mortality, Delivery of an FD device through the smallest available catheters is crucial to treat aneurysms arising from distal, small-caliber vessels. While it is unclear whether flow diversion treatment in small vessels is more likely to result in clinical complications (17), evidence indicates that interventionalists are more likely to be met with intraprocedural technical difficulties in these cases, such as navigating increased vessel tortuosity (18,19). It is notable that in this study, all aneurysms were located on small intracranial arteries, many of which had less than ideal circumstances; a majority of aneurysms were on the ACoA, involving the right or left A1-A2 segments, and a few aneurysms recurred after coil embolization.…”

Early clinical experience with the p48MW HPC and p64MW HPC flow diverters in the anterior circulation aneurysm using single anti-platelet treatment

“…2 However, since these early studies there has been a large amount of clinical data published suggesting that flow diversion is a viable option for the treatment of aneurysms located more distally [3][4][5][6][7][8][9][10][11][12] as well as within smaller vessels 13,14 and this has led to the development of devices such as the Silk Vista Baby (Balt, Montmorency, France), [15][16][17] FRED Junior (MicroVention, Aliso Viejo, California, USA) [18][19][20] and p48MW (HPC) (phenox, Bochum, Germany). [21][22][23][24][25][26][27] Simultaneously, there has been recognition that devices requiring use of a single antiplatelet treatment (SAPT) may prove advantageous and limit the risk of haemorrhagic complications. 28,29 The Hydrophilic Polymer Coating (HPC, phenox, Bochum, Germany) was developed to limit the need for dual antiplatelet therapy (DAPT) and can be applied to flow diverters as well as other nitinol surfaces.…”