A Comparison of a Fully Covered and an Uncovered Segmented Biodegradable Esophageal Stent in a Porcine Model: Preclinical Evaluation of Degradation, Complications, and Tissue Reactions

Figure 4

Endoscopic view of tissue reactions caused by an uncovered biodegradable stent. ((a) and (b)) Weeks 1 and 2: circumferential inflammation and nodular hyperplasia ingrowth. ((c)–(f)) Weeks 3–6: significant tissue reactions at contact points between the stents and the esophageal mucosa, with confluent nodules. ((g)-(h)) Weeks 7-8: confined tissue reactions, inflammation, and confluent nodular tissues gradually became alleviated. (i) Week 9: light scars were left. ((j)–(l)) Weeks 10–12: normal esophageal mucosa was present. TRS scores for weeks 1–12 were 2, 2, 3, 3, 3, 3, 2, 2, 0, 0, 0, and 0 for this case.

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