Length of maxillomandibular discrepancy may not predict tongue base airway obstruction severity among infants with...

To evaluate the relationship between severity of micrognathia and mandibular distraction distance required to alleviate symptoms among neonates with isolated Robin Sequence (iRS), as measured by frontal nasomental (FNM) angle from pre-operative CT-based surgical planning models.

This pilot study was a retrospective cohort included sixteen neonates with iRS. Data was collected via chart review.

Urban, tertiary care academic medical center.

Severity of preoperative micrognathia was approximated via measuring frontal nasomental (FNM) angle from pre-operative CT-based surgical planning models. Linear regression was used to determine the association between FNM angle and distraction distance. The correlation coefficient and F-statistic were calculated to determine the overall significance of the regression model. A p-value less than 0.05 was considered statistically significant.

The mean age at surgery was 40.38 days and 50% were male. The mean distance distracted during surgery was 11.45 mm. After controlling for other possible confounding factors, there was no statistically significant relationship between FNM angle and required distraction distance (Adj R² = -0.2, p = 0.71). Similarly, no association was found between the activation distance required and pre-operative maximum pCO₂ (Adj R2 = -0.453, p = 0.92).

These findings suggest that severity of micrognathia may not proportionately represent the degree of glossoptosis causing upper airway obstruction and FTT in infants with iRS.