gms | German Medical Science

Objective: Endovascular flow diversion and -modulation became recently an accepted method for the treatment of neurovascular dissections and side-wall aneurysms. p64 is a braided, self-expanding Nitinol implant. In comparison with most other devices with a similar function, p64 has a radial force in the same range, offers a denser vessel wall coverage and can be withdrawn after complete deployment. The initial clinical experience with this device will be presented.

Method: 136 patients (59 male) with 139 target lesions underwent 159 treatment sessions in a single neurovascular center. The target lesions (per procedure) included 81 saccular aneurysms, 56 fusiform aneurysms, 13 neurovascular dissections and 7 CCFs. Apart from 88 unruptured lesions without any previous treatment, 33 target lesions were previously treated with a flow diverter or a stent, 19 were remnants after coiling and 6 were treated after partial clipping or failed surgery. The majority of target lesions (123) were located in the anterior circulation, with 34 lesions in the posterior circulation. The fundus of the saccular aneurysms had a median diameter of 4 mm. In 118/157 procedures a single p64 was deployed.

Results: Complete coverage of the target lesion was achieved in 94%. No device malposition was encountered. Predilatation was performed in 17 cases, postdilatation in 9. During the first angiographic follow-up after 91 days (median), complete occlusion was confirmed in 52/110 lesions, minor remnants were found in 25/110 and significant remnants were present in 33/110. For 38 lesions a second DSA follow-up was available after 8.6 months (median). Complete occlusion and a minor remnant was observed in 24 and 5 lesions, respectively. A significant remnant was present in 9 lesions. Neither a SAH from a target lesion nor an ICH in the dependent brain or in a remote location occurred. Neurological deficits due to ischemic events were transient in 11 and permanent in 3 patients. Two patients died (1 from pneumonia, 1 from access related ICA dissection). Seven out of 10 side branch occlusions remained asymptomatic. All 11 patients with minor to moderate intimal hyperplasia developed no related symptoms.

Conclusions: p64 allows safe and efficacious reconstruction of extra- and intracranial vessel dissections. In saccular aneurysms a single device is mostly sufficient to induce vessel remodeling, resulting in aneurysm obliteration. Fusiform aneurysms may need more complex procedures with the use of several devices.