Resolution of vocal fold immobility in preterm infants

Abstract Introduction Vocal fold immobility (VFI) is an important sequela of preterm birth due to patent ductus arteriosus (PDA) ligation and invasive ventilation. A minority of these patients experience VFI resolution. The purpose of this study is to determine factors associated with VFI resolution in preterm infants. Methods This is a case control study of preterm ( Results Of 71 patients with VFI and adequate follow-up, 17 (23.9%) experienced resolution. Median (range) follow-up was 25.7 (0.4–91.3) months and time to resolution 4.4 (0.4–38.8) months. Compared to the ongoing-VFI cohort, those who experienced resolution had higher median gestational age (31 vs 25 weeks, p = 0.006) and birth weight (1550 vs 765 g, p = 0.02), and lower likelihood of undergoing PDA ligation (47.1% vs 77.8%, p = 0.02). On multivariate analysis, history of PDA ligation remained independently associated with a lower likelihood of VFI resolution (p = 0.02, OR 0.2, 95% CI 0.1–0.8). Among PDA ligation patients, birth weight >1000 g was more common in the resolution cohort compared to the ongoing-VFI cohort (62.5% vs 24.4%, p = 0.047). Conclusion While lower birth weight and gestational age are known risk factors for VFI following PDA ligation, in this study, these factors were also associated with a decreased likelihood of VFI resolution. Furthermore, PDA ligation appears to be a risk for both the development and persistence of VFI. This evidence should inform prognosis and intervention decisions for preterm infants with VFI.