title: Immunohistochemical Analysis of Debris Captured by Filter-Type Distal Embolic Protection Devices for Carotid Artery Stenting.
abstract: BACKGROUND
  Little is known about the micro-debris captured in filter-type distal embolic protection devices (EPD) used for carotid stenting (CAS). This study aimed to determine the histological and immunohistochemical characteristics of such debris by using a new liquid-based cytology (LBC) technique.
  
  
  METHODS
  Fifteen patients who underwent CAS using a filter-type distal EPD (FilterWire EZ; Boston Scientific, Marlborough, MA, USA) were included in the study. After gross inspection of each recovered filter device, micro-debris were collected using a new LBC technique (SurePath; TriPath Imaging, Inc., Burlington, NC). Histological and immunohistochemical analysis of the recovered debris was performed. The pre- and postoperative brain magnetic resonance imaging and neurological status of each patient were also reviewed.
  
  
  RESULTS
  No patient developed ipsilateral symptomatic stroke due to a thromboembolic event. All 15 patients (100%) had microscopically identifiable debris in the filters, whereas gross inspection detected visible debris only in 5 patients (33.3%). Histological analysis revealed various types of structural components in an advanced atheromatous plaque, including fragments of fibrous cap, calcified plaque, smooth muscle cells, and necrotic tissue fragment infiltrated with monocytes and macrophages.
  
  
  CONCLUSIONS
  Filter-type EPDs may contribute to reducing the risk of CAS-related embolic events by capturing micro-debris even when gross inspection of the recovered filter shows no visible debris in the device.
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, Japan.
authors.forename: Yukinao
authors.initials: Y
authors.lastname: Kambayashi
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, Japan. Electronic address: iyuki@jikei.ac.jp.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yuki
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Ishibashi
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Ikemura
authors.affiliation: Department of Pathology, Jikei University School of Medicine, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Umezawa
authors.affiliation: Department of Pathology, Jikei University School of Medicine, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, Japan.
authors.forename: Issei
authors.initials: I
authors.lastname: Kan
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Takao
authors.affiliation: Department of Neurosurgery, Jikei University School of Medicine, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Murayama
mesh_terms: D000199:Actins / Q000378:metabolism; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D015214:Antigens, Differentiation, Myelomonocytic / Q000378:metabolism; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000628:therapy*; D038524:Diffusion Magnetic Resonance Imaging; D057505:Embolic Protection Devices / Q000009:adverse effects*; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation*; D005260:Female; D005355:Fibrosis / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism; D000097382:CD68 Molecule
chemical_list: D000199:Actins; D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; C067980:CD68 antigen, human; D000097382:CD68 Molecule
keywords: Carotid artery stenting; embolic protection device; histological analysis; micro-debris