The Enterprise2 Stent for Endovascular Treatment of Intracranial Aneurysms: Short-Term Results From a Single Center Experience

Abstract

Background: Self-expanding devices, such as the Enterprise VRD (EP-VRD) have widely used for stent-assisted coiling treatment in wided-necked aneuryms while some thromboembolic complications were reported due to its incomplete stent apposition (ISA). We report our experiences on the novel Enterprise2 (EP-VRD2) stent in vivo in the treatment of intracranial and cranial cervical junction aneurysms.Methods: Twenty-five consecutive patients with intracranial or cranial cervical junction aneurysms were treated with EP-VRD2 stents retrospectively collected in our institution. We use the ‘jailing' technique in all cases and deployed the stent by using pushing over the outer curve technique. The 3- or 6-monthS follow-up was done regularly by DSA.Results: Twenty-five EP-VRD2 stents were implanted to treat 21 aneurysms at the siphon segment of internal carotid artery (ICA), one at the petrous segment, two at the cervical segment, one at the verteral artery with five accompanied with stenosis. Two patients had kinking during the procedure and were solved by microwire or microcatheter massaging. Four patients with a larger arc angle and a smaller radius of the parent vessel was detected ISA. No patient underwent the ischemic event after the operation. Twenty-three of 25 patients were evaluated after 3- or 6-months by DSA, 22 showed complete occlusion (RROC1), one slight re-stenosis in the follow-up within those five patients with stenosis. A length of 23 mm seemed associated with ISA (p < 0.01).Conclusion: The EP-VRD2 performed well in our small patient series; however, ISA could still occur with a sharp angle of the parent vessel.

Enterprise 2 Stent-Assisted Embolization of Paraclinoid Aneurysms: A Single Center Preliminary Study

“…Chen et al studied EP stents in the treatment of intracranial aneurysms and found that the ISA rate of the inner or outer curvature was 16% (4/25). 20 In the present study, the ISA rate of the inner or outer curvature was 13.27% (13/98), lower than reported by Chen et al The possible reason is that the EP2 stent increases the amplitude based on the original sine wave of the preceding generation, allowing the stent to compress on the inner curvature and extend on the outer curvature. This process enlarges the curvature of the stent, which can adapt to the curve vessels and improve adherence to the vessel wall.…”

“…Without affecting the patency of the surrounding branch vessels, we changed to a slightly longer stent, and the ISA improved. Similarly, Chen et al properly extended the length of the stent, and the ISA rate was upgraded; 20 that is to say, the length of the stent appears to be an essential factor of ISA. Briefly, the vessel’s inner bending radius and length of the stent can affect ISA and the surgical effect, which were consistent with the results of the present study ( P < 0.01).…”

“…Traditional stents such as Enterprise or Neuroform cannot achieve satisfactory assisted embolization. 20 , 21 In addition, because paraclinoid aneurysms have a relatively curve structure and a larger bending angle, the stent usually cannot attach well to the vessel wall, significantly reducing the therapeutic effect. 22 , 23 Therefore, a novel stent that can solve these curved or wide neck aneurysms is urgently needed.…”

“…In addition, the EP2 stents increase the diameter of the main body from 4.5 mm to 5 mm and expand the diameter of the flare ends from 7 mm to 7.3 mm to better adhere to the blood vessels and improve the compactness of embolization. 20 The closed-cell designs of EP and EP2 stents enable them to be recaptured and repositioned before full release, which is particularly important in curved vessels; in these vessels, the stents are often challenging to release successfully, and the procedure usually requires several adjustments to achieve satisfactory results. However, due to the curved vessels, not all the stents released completely adhere to the wall.…”

Effects of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms

“…Kato et al [ 14 ] used the double volume fusion technique based on C-arm CT to compare stent-vessel apposition of three stents (EP2, Neuroform, and Atlas) and found the frequency of crescent sign detection in the bending vessels was highest for the EP2 stent (27%, 8%, and 0, respectively). Chen et al [ 15 ] used VasoCT to observe EP2 stent release and reported that 6 of 25 stents (24%) showed malposition: 2 showed kinking and the other 4 showed large gaps between the stent and vessel wall. In our study, VasoCT was performed on 21 stents that were all implanted in the vessels with large curves, 5 (23.8%) showed incomplete stent apposition, two at the stent body, and three at the end opening.…”