ASPO013 - Balloon Dilation for Chronic Subglottic Stenosis in a Rabbit Model
Friday, April 29, 2022
4:30 PM – 5:00 PM CT
Location: Landmark C
Orna Katz Kadosh, MD1, Ivanna Nebor, MD2, Matthew M. Smith, MD3, Catherine K. Hart, MD, MS3, Meredith E. Tabangin, MPH4, Debora I. Sinner, PhD5, Alessandro de Alarcon, MD,MPH3;
1Department of Otolaryngology, Harvard Medical School, Massachusetts Eye and Ear, Boston, MA, 2Division of Pediatric Otolaryngology and Head and Neck Surgery, Cincinnati Children's Hosp. Med. Ctr., Univ. of Cincinnati Coll. of Med., Cincinnati, OH, 3Division of Pediatric Otolaryngology and Head and Neck Surgery, Cincinnati Children's Hosp. Med. Ctr., Univ. of Cincinnati Coll. of Med., Cincinnati, OH, 4Division of Biostatistics and Epidemiology, Cincinnati Children's Hosp. Med. Ctr., Univ. of Cincinnati Coll. of Med., Cincinnati, OH, 5Division of Neonatology and Pulmonary Biology, Perinatal Institute, Cincinnati Children's Hosp. Med. Ctr., Univ. of Cincinnati Coll. of Med., Cincinnati, OH.
Pediatric Otolaryngology Fellow Department of Otolaryngology and Head and Neck Surgery at Massachusetts Eye and Ear Infirmary Harvard Medical School Boston , Massachusetts
Introduction:Endoscopic balloon dilation(BD)is commonly used to manage subglottic stenosis(SGS). Our aim is to examine the short-term effect of single and repeated BD on mature chronic SGS in a rabbit model.
Methods: We conducted a prospective study including 12 New Zealand white rabbits. Chronic mature SGS was induced endoscopically. BD was done with 8 mm balloon for 30 sec at 17ATM. Animals were assigned to 3 groups; all groups had the first BD performed at 8 weeks post injury, between each BD there were 2 weeks, and all groups were sacrificed 1 week after the last BD. Group 1 was subjected to 1 BD; group 2 underwent 2 BDs, group 3 underwent 3 BD’s. Animals were humanely euthanized for histopathological examination of the subglottic area and microscopic measurement of the cricoid lumen and the total submucosal area (SMA). SMA was measured in mm2, from the inner cricoid cartilage to the inner cricoid lumen, a higher number indicates thicker submucosal area. Hematoxylin Eosin and Masson Trichrome stained slides were evaluated by a blinded pathologist and pathological scoring was used to grade pathological changes in each group compared to each other and to diseased control without BD.
Results: Mean (SD) cricoid lumen area was previously measured in healthy control without injury 24.2 (4.9) mm2 in diseased control without any BD: 17.8 (3.5) mm2. Post BD measurements in Group 1: 13.7 (3.6) mm2, Group 2: 22.0 (4.8) mm2, Group 3: 23.0 (2.8) mm2. Mean cricoid lumen area after 1 BD (Group 1) was significantly smaller than healthy control without injury, Group 2, and Group 3 (p < 0.05). Multiple BDs were needed to reach normal size cricoid lumen. SMA values; mean healthy control was 19.8 (3.9) mm2, group 3 was 21.8 (1.0) mm2, while group 1 was 28.6 (2.7) mm2. Mean SMA values did not significantly differ between groups (p=0.34). Pathological scoring after BD in all groups showed mild to moderate pathologic changes as compared to our diseased control without BD which had severe pathologic changes.
Conclusion:We examined the short-term effects of single vs repeated balloon dilation in a rabbit model of chronic SGS. Our study determines that when treating chronic SGS, multiple BD are needed to restore normal size of the cricoid lumen, and histopathologic changes were severe without any BD intervention.