Histological examination of vascular damage caused by stent retriever thrombectomy devices.
OBJECTIVE
Although the recently marketed stent retriever thrombectomy devices have demonstrated a high recanalization rate and favorable clinical outcomes, there is a concern about the risks of intimal injuries when pulling out the stent in the unfolded position. In this study, the Solitaire Flow Restoration System and the Trevo retriever were used in a histopathological comparison of vascular injuries caused by stent retriever thrombectomy devices.


METHODS
Rabbit carotid arteries were used in the experiments with stent retriever thrombectomy devices. Carotid artery samples were harvested either 1 or 2 weeks postoperatively for histological examination.


RESULTS
Histological changes caused by the use of stent retriever thrombectomy devices were observed from the intimal to medial layers. With the Solitaire FR 4 mm, intimal and medial thickening was observed 1 week postoperatively, and progression of intimal thickening was observed 2 weeks postoperatively. The extent of intimal thickening tended to be greater with the Solitaire FR 6 mm than with the Solitaire FR 4 mm, but this difference was not significant. Compared with the Solitaire FR 4 mm, the Trevo had a significantly smaller area of intimal thickening.


CONCLUSIONS
Although there are some differences among devices, results from this study indicate that stent retriever thrombectomy devices induce vascular damage that extends to the medial layer.
Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Daisuke
D
Arai
Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Akira
A
Ishii
Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Hideo
H
Chihara
Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Hiroyuki
H
Ikeda
Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan.
Susumu
S
Miyamoto
D000818:Animals; D001808:Blood Vessels / Q000293:injuries* / Q000473:pathology*; D020212:Carotid Artery Injuries / Q000209:etiology / Q000473:pathology; D020878:Device Removal / Q000009:adverse effects*; D008297:Male; D011817:Rabbits; D015607:Stents; D020521:Stroke / Q000601:surgery; D017131:Thrombectomy / Q000009:adverse effects* / Q000295:instrumentation*; D017539:Tunica Intima / Q000473:pathology
Intervention; Stroke; Thrombectomy