Tracheobronchomalacia (TBM) is a congenital, or acquired, deficiency of tracheal and/or bronchial cartilages resulting in partial-to-complete collapse of tracheobronchial segments. TBM presents with dynamic airway collapse and respiratory difficulties. In severe cases, TBM results in acute life-threatening events and death. Severe cases require surgical intervention, including tracheal stenting followed by tracheotomy with positive pressure ventilation. However, current stenting, or other mechanical methods to ensure an open trachea, are associated with failure, morbidity and mortality. We have developed a bioresorbable splint for TBM that can be custom designed for patient specific anatomy and specific mechanical properties. The splint is fabricated using a 3D printing process which we have developed for bioresorbable PCL. We recently implanted the splint to treat imminently life-threatening TBM successfully in a 3-month old patient. The purpose of the current proposal is to investigate the effect of designed splint mechanical stiffness in a large, rapid growing animal model, the Yorkshire Pig, which experiences the equivalent of 2-3 years of human tracheal growth in a 4-6 month period. We will test two different splint designs along with no intervention in a pig tracheomalacia model to determine 1) the efficacy of using the splint to correct TBM and 2) the effect of splint design on tracheal growth.

Public Health Relevance

Tracheobronchomalacia (TBM) is a deficiency of major airway structures that results in respiratory difficulties and death in the most severe cases. We have developed and successfully used (in a single case) a customized, laser-printed, resorbable splint to treat TBM. The purpose of the current proposal is to investigate the properties of the splint in a rapidly growing animal model, the Yorkshire Pig, before broader application.

National Institute of Health (NIH)
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Exploratory/Developmental Grants (R21)
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Bioengineering, Technology and Surgical Sciences Study Section (BTSS)
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Maholmes, Valerie
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University of Michigan Ann Arbor
Schools of Medicine
Ann Arbor
United States
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Morrison, Robert J; Sengupta, Shayan; Flanangan, Colleen L et al. (2017) Treatment of Severe Acquired Tracheomalacia With a Patient-Specific, 3D-Printed, Permanent Tracheal Splint. JAMA Otolaryngol Head Neck Surg 143:523-525
Morrison, Robert J; Hollister, Scott J; Niedner, Matthew F et al. (2015) Mitigation of tracheobronchomalacia with 3D-printed personalized medical devices in pediatric patients. Sci Transl Med 7:285ra64
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Hollister, Scott J; Flanagan, Colleen L; Zopf, David A et al. (2015) Design control for clinical translation of 3D printed modular scaffolds. Ann Biomed Eng 43:774-86
Morrison, Robert J; Kashlan, Khaled N; Flanangan, Colleen L et al. (2015) Regulatory Considerations in the Design and Manufacturing of Implantable 3D-Printed Medical Devices. Clin Transl Sci 8:594-600
Zopf, David A; Flanagan, Colleen L; Wheeler, Matthew et al. (2014) Treatment of severe porcine tracheomalacia with a 3-dimensionally printed, bioresorbable, external airway splint. JAMA Otolaryngol Head Neck Surg 140:66-71