Evidence of Submucosal Nerve Hypertrophy in Patients with Laryngomalacia
SM El Jamal, R Glade, P Munson, G Richter, AG Saad. University of Arkansas for Medical Sciences, Little Rock, AR
Background: Laryngomalacia is a common cause of stridor in newborns. The underlying defect that causes laryngomalacia remains unknown; however, mechanisms involving inflammation and neuromuscular weakness have been proposed. The aim of this study is to evaluate the specific difference in diameter and surface area of submucosal nerves in laryngomalacia patients versus control subjects along with other stromal changes commonly observed in these patients.
Design: Patients with laryngomalacia in the period from January 2008 until August 2009 were collected from the files of a Children's Hospital. Laryngeal tissues from autopsy cases were used as a control group. Demographic data were collected from pathology reports. Each slide is scanned, the largest submucosal nerve spotted, image captured, digitized and measured for area and perimeter. Stromal abnormalities including myxoid degeneration, edema and inflammatory infiltrate were also evaluated.
Results: Supra-arytenoid tissue from 43 patients with laryngomalacia (25 males and 18 females) (age: median 0.41 years; range: 0.02-3.19 years) and 13 controls (12 males and 1 female) (age: median 0.5 years; range: 0.07-1.41 years) were examined. Both groups were matched for age (P=0.67). There was marked submucosal nerve hyperplasia in patients with laryngomalacia compared to controls group. In the patients group, nerve perimeter (median: 1765 µ; range 452-3877 µ) was higher than in the control group (median: 948.7 µ; range 413-3253.3 µ); this difference was statistically significant (P=0.002). In addition nerve surface (median: 182905 µ2; range 13938-961007 µ2) was significantly higher than in the control group (median: 60405 µ2; range 9409-726521 µ2 P=0.02). Furthermore, there was increased incidence of stromal abnormalities such as edema, submucosal myxoid degeneration, and lymphocytic infiltrate in the patients group.
Conclusions: In this study, we demonstrate the presence of significant submucosal nerve hyperplasia in children with laryngomalacia compared to controls. In addition, these patients showed an increased incidence of stromal abnormalities. The cause-effect relationship between nerve and stromal changes and laryngomalacia is still unknown. However, our results suggest that laryngomalacia is related, at least in part, to an underlying neural abnormality.
Category: Head & Neck
Wednesday, March 24, 2010 9:30 AM
Poster Session V # 154, Wednesday Morning