Influence of a dexamethasone-eluting covered stent on tissue reaction: an experimental study in a canine bronchial model.
This study was designed to evaluate the feasibility and efficacy of a dexamethasone (DXM)-eluting, covered, self-expanding metallic stent to reduce tissue reaction following stent placement in a canine bronchial model. We placed a DXM-eluting, polyurethane-covered, self-expanding metallic stent (drug stent, DS) and a polyurethane-covered, self-expanding metallic stent (control stent, CS) alternately in each left main bronchus and left lower lobe bronchus in 12 dogs. The stents were 20 mm in diameter and length when fully expanded. The dose of DXM was approximately 36.7 mg in each DS, but was absent in the CS. The dogs were euthanased 1 week (n=4), 2 weeks (n=4) or 4 weeks (n=4) after stent placement. Histologic findings, such as epithelial erosion/ulcer or granulation tissue thickness, were obtained from the mid-portion of the bronchus, where the stent had been placed, and evaluated between DS and CS. There were no procedure-related complications or malpositioning of any of the bronchial stents. Stent migration was detected in one dog just before euthanasia 1 week following stent placement. Stent patency was maintained until euthanasia in all dogs. Epithelial erosion/ulcer (%) was significantly less in the DS (mean+/-standard deviation, 46.88+/-23.75) than in the CS (73.75+/-14.08) (P=0.026) for all time-points. There was a decrease in epithelial erosion/ulcer as the follow-up period increased in both DS and CS. The granulation tissue thickness (mm) was less in DS (2.63+/-2.05) than in CS (3.49+/-2.95), although the difference was not significant (P=0.751) for all time-points. There was a tendency toward an increase in granulation tissue thickness and chronic lymphocytic infiltration as the follow-up period increased in both DS and CS. In conclusion, DXM-eluting, covered, self-expanding metallic stent seems to be effective in reducing tissue reaction secondary to stent placement in a canine bronchial model.
Shin
Ji Hoon
JH
Department of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Songpa-gu, Seoul, South Korea.
Song
Ho-Young
HY
Seo
Tae-Seok
TS
Yuk
Soon Hong
SH
Kim
Young-Hwa
YH
Cho
Yong-Mee
YM
Choi
Gi Bok
GB
Kim
Tae-Hyung
TH
Suh
Ji-Yeon
JY
D000818:Animals; D001980:Bronchi / Q000187:drug effects*; D020099:Coated Materials, Biocompatible; D003907:Dexamethasone / Q000008:administration & dosage*; D004285:Dogs; D005240:Feasibility Studies; D011140:Polyurethanes; D015641:Radiography, Interventional; D018709:Statistics, Nonparametric; D015607:Stents
D020099:Coated Materials, Biocompatible; D011140:Polyurethanes; D003907:Dexamethasone