In Memoriam: The Matrix Coil

Differences in tissue proliferation and maturation between Matrix2 and bare platinum coil embolization in experimental swine aneurysms

“…In 2006, Niimi et al reported that embolization of Matrix2 coils resulted in inferior recanalization rates compared with BP coils [6]. Since then, several other studies have concluded that Matrix2 coils have little or no advantage over, but are not inferior, to BP coils [5,7,17]. There are reportedly no significant differences in the rates of overall aneurysm recurrence, major recanalization or retreatment in patients treated with BP coils compared with those treated with Matrix2 coils [17].…”

“…Clinical and anatomical results in the treatment of ruptured intracranial aneurysms (CLARITY) series, immediate-and mid-term anatomic results and evolution of aneurysm occlusion were not different in patients with ruptured aneurysms treated with BP or Matrix coils [18,19]. The Matrix and Platinum Science (MAPS) trial provided level one evidence that the Matrix2 has no advantages over the BP coil in terms of the recurrence rate of treated intracranial aneurysms [5,7]. We found, however, a greater depth of proliferating tissue and more extensive fibrosis in the Matrix2 coil-treated group, and some similarities in the histological characteristics of the newly formed tissue when compared with BP coils.…”

“…There is, however, evidence of improved mechanical performance and anatomic outcome in the short-, medium-and long-terms with Matrix2 coils [2,4], although there have been several conflicting reports that superior anatomic outcomes can be achieved with BP coils [5][6][7].…”

Histological and Transmission Electron Microscopy Results after Embolization with HydroSoft/HydroFrame Coils in Experimental Swine Aneurysm

“…Although we previously compared Matrix2 with bare platinum coils [8], we only compared hydrogel coils and bare platinum coils in the present study. Because several endovascular approaches are now available for the treatment of intracranial aneurysms, including standard coiling, balloon-assisted coiling, stent-assisted coiling, and flow diversion, Matrix2 coils are no longer frequently used in the clinical setting [35].…”

Peripheral macrophages in the development and progression of structural cerebrovascular pathologies

“…223 While previous efforts to develop biologically-active coils yielded underwhelming results and led their abandonment in clinical practice, recent efforts have explored augmenting macrophage recruitment to promote aneurysmal healing. 224,225 Indeed, studies have demonstrated that MCP-1 coated coils increase the rate of aneurysm healing through monocyte recruitment in experimental aneurysms, with IL-6 and osteopontin serving as key regulators. 226,227…”