Liquid (188)Re-filled balloon dilation for the treatment of refractory benign airway strictures: preliminary experience

Tuberculous Tracheobronchial Strictures Treated with Balloon Dilation: A Single-Center Experience in 113 Patients during a 17-year Period

PURPOSE

To evaluate the safety and effectiveness of balloon dilation in the treatment of tuberculous tracheobronchial strictures (TTBSs) in a series of 113 patients at a single institution.

MATERIALS AND METHODS

The institutional review board approved the study and waived the requirement to obtain informed consent. Between 1997 and 2014, under bronchoscopic and fluoroscopic guidance, a total of 167 balloon dilation sessions were performed in 113 consecutive patients (14 male and 99 female patients; mean age, 37 years [age range, 17-73 years]), with a range of one to eight sessions per patient (mean, 1.5 sessions). Outcomes were number and/or frequency of balloon dilations, technical success, primary and secondary clinical success, improvement in respiratory status, airway patency rate, and alternative treatment after balloon dilation. A two-tailed paired t test and the Kaplan-Meier method were used to evaluate the improvement in respiratory status and airway patency rate after balloon dilation, respectively.

RESULTS

Dilation was successful in 82 patients (73%) after single (n = 67) or multiple (n = 15) balloon dilations, with a mean follow-up of 30.3 months. Clinical failure occurred in 31 patients (27%). In these 31 patients, symptoms recurred 1 day to 113 months (mean, 13 months) after repeat balloon dilations. These 31 patients required alternative treatment, including temporary stent placement (n = 12), cutting balloon dilation (n = 12), radiation-eluting balloon dilation (n = 3), and surgery (n = 4). Before, immediately after, and 1 month after the procedure, pulmonary function test results showed significant improvements in mean forced vital capacity (P < .001), forced expiratory volume in 1 second (P = .001), forced expiratory flow in the midexpiratory phase (P = .020), and peak expiratory flow (P = .005).

CONCLUSION

Balloon dilation of TTBSs is a safe, minimally invasive primary treatment that relieved symptoms in a large percentage of patients (73%). In patients with TTBSs refractory to balloon dilation, temporary stent placement, cutting balloon dilation, or radiation-eluting balloon dilation can be an alternative treatment.

A dual-inhibition study on vascular smooth muscle cells with meclofenamic acid and β-irradiation for the prevention of restenosis

PURPOSE

Restenosis is still one of the major limitations after angioplasty. A therapeutic treatment combining β-irradiation and pharmacologic cyclooxygenase-2 inhibition was employed to study the impact on vascular smooth muscle cells (SMCs).

MATERIALS AND METHODS

The effects of meclofenamic acid in combination with yttrium-90 ((90)Y) on cell growth, clonogenic activity, cell migration, and cell cycle distribution of human aortic SMCs were investigated. Treatment was sustained over a period of 4 days and recovery of cells was determined until day 20 after initiation. The hypothesis was that there is no difference between control and treated groups.

RESULTS

A dose-dependent growth inhibition was observed in single and combined treatment groups for meclofenamic acid and β-irradiation. Cumulative radiation dosage of 8 Gy completely inhibited colony formation. This was also observed for 200 μM meclofenamic acid alone or in combination with minor β-irradiation dosages. Results of the migration tests showed also a dose dependency with additive effects of combined therapy. Meclofenamic acid 200 μM alone and with cumulative β-irradiation dosages resulted in an increased G2/M-phase share.

CONCLUSIONS

Incubating human SMCs with meclofenamic acid and (90)Y for a period of 4 d (ie, 1.5 half-life times) resulted in an effective inhibition of smooth muscle cell proliferation, colony formation, and migration.

Interventional management of tracheobronchial strictures

Tracheobronchial balloon dilation and stent placement have been well used in the treatment of patients with benign and/or malignant diseases. Balloon dilation is the first option in the treatment of benign airway stenosis. Although balloon dilation is simple and fast, recurrence rate is high. Stent placement promptly relieves acute airway distress from malignant extraluminal and intraluminal airway obstruction. Temporary stent placement may be an alternative for benign airway strictures refractory to balloon dilation. This article reviews the indications, pre-procedure evaluation, technique, outcomes and complications of balloon dilation and stent placement with regard to benign and malignant tracheobronchial stenoses.

IN-1233, an ALK-5 inhibitor: prevention of granulation tissue formation after bare metallic stent placement in a rat urethral model

PURPOSE

To evaluate the efficacy of an activin receptor-like kinase-5 inhibitor, IN-1233, for the prevention of tissue hyperplasia after bare stent placement in a rat urethral model.

MATERIALS AND METHODS

Procedures were performed in accordance with the National Institutes of Health guidelines for humane handling of animals; approval of the committee of animal research was obtained. In 20 Sprague-Dawley male rats (weight range, 300-350 g), a self-expanding metallic bare stent was inserted in the urethra by using fluoroscopic guidance. One group of 10 rats (group A) was treated with IN-1233, the other group of 10 rats (group B) received no treatment. Retrograde urethrography was performed 4 and 8 weeks after stent placement. All rats were sacrificed at 8 weeks for histologic analysis.

RESULTS

Stent placement was technically successful in all rats. The average stent diameter was significantly larger in group A compared with group B at follow-up retrograde urethrography performed 4 (P = .006) and 8 (P < .001) weeks after stent placement. At histologic analysis, the percentage of granulation tissue area (P < .001), thickness of submucosal fibrosis (P < .001), and number of epithelial layers (P < .001) were significantly decreased in group A compared with group B. Inflammatory cell infiltration (P < .001) was significantly increased in group A compared with group B.

CONCLUSION

IN-1233 is effective for the prevention of granulation tissue formation after bare metallic stent placement in a rat urethral model.