Collagen microbeads: experimental evaluation of an embolic agent in the rete mirabile of the swine.
OBJECTIVE
To evaluate the histologic and angiographic effects of collagen microbeads as an embolic agent in the swine rete mirabile.


METHODS
Human collagen particles (380 +/- 100 microns) of spheroidal shape and smooth surface were used to embolize the rete mirabile in five swine. Control angiograms and pathologic examinations were obtained immediately and sequentially from 3 to 35 days after embolization.


RESULTS
The collagen particles were easy to inject through microcatheters. Embolization was always angiographically complete and persistent for at least 5 weeks. Histologic studies showed occlusion of 25% to 50% of the rete vessels. After 3 and 5 weeks' follow-up, transmural and adventitial chronic inflammation was present. Inflammatory infiltrates included lymphohistiocytic cells and scattered eosinophils. The foreign-body giant-cell reaction was pronounced. No evidence of angionecrosis or focal hemorrhage was shown.


CONCLUSIONS
Collagen microbeads are a promising experimental embolic agent, with potential future applications in humans.
Turjman
F
F
Department of Radiological Sciences (Endovascular Therapy), University of California at Los Angeles Medical Center, USA.
Massoud
T F
TF
Vinters
H V
HV
Ji
C
C
Tardy
M
M
Guglielmi
G
G
Viñuela
F
F
D000818:Animals; D001921:Brain / Q000098:blood supply*; D002343:Carotid Artery, Internal / Q000000981:diagnostic imaging / Q000473:pathology; D002941:Circle of Willis / Q000000981:diagnostic imaging / Q000473:pathology; D003094:Collagen; D004621:Embolization, Therapeutic / Q000379:methods*; D005549:Foreign-Body Reaction / Q000473:pathology; D015745:Granuloma, Foreign-Body / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D010316:Particle Size; D010614:Pharynx / Q000098:blood supply; D011859:Radiography; D013499:Surface Properties; D013552:Swine
D003094:Collagen