Technical Feasibility and Histological Analysis of Balloon-Expandable Metallic Stent Placement in a Porcine Eustachian Tube

There is a clinical need to develop a stent to treat obstructive and refractory Eustachian tube dysfunction (ETD) after balloon Eustachian tuboplasty. An animal model for stent placement in the Eustachian tube (ET) is needed to develop optimal designs and materials, as stents for ETD have not been clinically applied. The purpose of this study was to evaluate the technical feasibility of stent placement and histological changes in a porcine ET model. Six ETs were evaluated in three pigs. Cobalt–chrome alloy stents with two different diameters were placed in the left and right ET of each animal (right, 3.5 mm; left, 2.5 mm). The outcomes were assessed by endoscopic and fluoroscopic imaging during the procedure, computed tomography after the procedure, and by histological examinations. Stent placement was technically successful in all specimens after metallic guiding sheaths were located in the nasopharyngeal end of the ET. The mean luminal diameters of the proximal, middle, and distal portions of the larger stents in the right ETs were 3.48 mm, 2.54 mm, and 2.15 mm, respectively. In the left ETs using smaller stents, these values were 2.49 mm, 1.73 mm, and 1.42 mm, respectively. The diameters of the inserted stents differed by stent location and the original diameter. Histological findings showed tissue hyperplasia with severe inflammatory cell infiltration at 4 weeks after stent placement. In conclusion, stent placement into the porcine ET was technically feasible, and stent-induced tissue hyperplasia was significantly evident. The luminal configuration of the placed ET stent changed according to its non-elastic nature and anatomical features of the porcine ET. Using this model, ET stents of various materials and designs with anti-inflammatory or anti-proliferative drugs can be optimized for future treatments of ET dysfunction.

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Factors associated with the technical difficulty of double-wire woven uncovered self-expandable metallic stent placement for malignant colorectal obstruction

10.26226/morressier.59a6b344d462b80290b54578 ◽

2017 ◽

Author(s):

Kenji Tominaga

Keyword(s):

Stent Placement ◽

Technical Difficulty ◽

Metallic Stent ◽

Colorectal Obstruction ◽

Factors Associated ◽

Expandable Metallic Stent ◽

Metallic Stent Placement

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Single Y-shaped tracheal self-expandable metallic stent for emergent carinal stenosis combined with stenosis of the right main and intermediate bronchi

Medicine ◽

10.1097/md.0000000000020498 ◽

2020 ◽

Vol 99 (22) ◽

pp. e20498 ◽

Cited By ~ 1

Author(s):

Yahua Li ◽

Ming Zhu ◽

Jianjian Chen ◽

Kewei Ren ◽

Li Wan ◽

...

Keyword(s):

Metallic Stent ◽

Expandable Metallic Stent ◽

The Right

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Assesment of placement of the esophageal self-expandable metallic stent in esophageal cancer in patients with or without citorreduction therapy

ABCD Arquivos Brasileiros de Cirurgia Digestiva (São Paulo) ◽

10.1590/s0102-67202007000300007 ◽

2007 ◽

Vol 20 (3) ◽

pp. 154-160

Author(s):

Gilson Kamiyama ◽

Paulo Sakai ◽

Eduardo Guimarães H. de Moura ◽

Shinichi Ishioka ◽

Ivan Cecconello ◽

...

Keyword(s):

Esophageal Cancer ◽

Survival Time ◽

Stent Placement ◽

Gastrointestinal Endoscopy ◽

Thoracic Esophagus ◽

Metallic Stent ◽

Advanced Esophageal Cancer ◽

Expandable Metallic Stent ◽

Stent Treatment ◽

Time Average

BACKGROUND: Placement of self-expanding metallic esophageal stent in patients with advanced esophageal cancer offers excellent palliation of dysphagia and tracheo-esophageal fistulas. However, the safety of stent in patients undergoing radio and/or chemotherapy is controversial, in terms of the greater risk of complications in cases where these two treatments are used in conjunction. AIM: To assess the use of stent in patients with advanced cancer of the mid-thoracic esophagus, by comparing patients undergoing cytoreductive therapy with patients who have not undergone this treatment, in relation to improvement in the dysphagia, rate of complications, period of effectiveness and survival time. METHODS: Fifty seven patients were evaluated retrospectively (16 women and 41 men, with an average age 62 years) with advanced squamous cell carcinoma of the mid-thoracic esophagus who underwent placement of the Ultraflex™ self-expandable metallic coated stent, at the Gastrointestinal Endoscopy Unit of São Paulo University Medical School between October 1988 and October 2004. Out of the 57 patients, 24 patients received adjuvant cytoreductive therapy, and 33 patients were only treated with the stent placement. RESULTS: After stent placement, there was improvement in dysphagia in both groups; there were no differences in the rate of complications, such as migration, pain, fistula, obstruction and compression of the airways; the period of effectiveness was significantly higher in the group submitted to cytoreductive therapy (average 123 days compared to 63 days), as was the survival time (average of 210 days, compared with 120 days). CONCLUSIONS: Improvement in dysphagia was statistically significant in both groups, irrespective of whether the patient had undergone adjuvant cytoreductive therapy; there were no differences in the rate of complications between the two groups and both the period of effectiveness of the stent treatment and the survival time were higher in the group with adjuvant cytoreductive therapy.

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