Pediatric Interventional Radiology: Blurring the Lines Between Specialties.

Medical imaging has transformed the ease and speed of patient care with provision of detailed evaluation of anatomic structures and disease processes. Interventional radiology uses imaging guided techniques to further diagnose or treat diseases with minimally invasive methods. These techniques are particularly helpful in treating pediatric patients.

Tracheobronchomalacia diagnosed by tracheobronchography in ventilator-dependent infants.

BACKGROUND: Tracheobronchomalacia prevalence in premature infants on prolonged mechanical ventilation is high. OBJECTIVE: To examine the prevalence of tracheobronchomalacia diagnosed by tracheobronchography in ventilator-dependent infants, and describe the demographic, clinical and dynamic airway characteristics of those infants with tracheobronchomalacia. MATERIALS AND METHODS: This retrospective review studies 198 tracheobronchograms performed from 1998 to 2011 in a cohort of 158 ventilator-dependent infants <2 years of age. Dynamic airway assessment during tracheobronchography determined the optimal positive end-expiratory pressure to maintain airway patency at expiration in those infants with tracheobronchomalacia. RESULTS: Tracheobronchograms were performed at a median age of 52 weeks post menstrual age. The primary diagnoses in these infants were bronchopulmonary dysplasia (53%), other causes of chronic lung disease of infancy (28%) and upper airway anomaly (13%). Of those with bronchopulmonary dysplasia, 48% had tracheobronchomalacia. Prematurity (P=0.01) and higher baseline - pre-tracheobronchogram positive end-expiratory pressure (P=0.04) were significantly associated with tracheobronchomalacia. Dynamic airway collapse during tracheobronchography showed statistically significant airway opening at optimal positive end-expiratory pressure (P < 0.001). There were no significant complications noted during and immediately following tracheobronchography. CONCLUSION: The overall prevalence of tracheobronchomalacia in this cohort of ventilator-dependent infants is 40% and in those with bronchopulmonary dysplasia is 48%. Infants born prematurely and requiring high pre-tracheobronchogram positive end-expiratory pressure were likely to have tracheobronchomalacia. Tracheobronchography can be used to safely assess the dynamic function of the airway and can provide the clinician the optimal positive end-expiratory pressure to maintain airway patency.

Quantification of humeral head deformity following neonatal brachial plexus palsy.

BACKGROUND: Neonatal brachial plexus palsy frequently leads to glenohumeral dysplasia if neurological recovery is incomplete. Although glenoid retroversion and glenohumeral subluxation have been well characterized, humeral head deformity has not previously been quantified. Nonetheless, humeral head flattening is described as a contraindication to joint contracture release and external rotation tendon transfers. This study describes a novel technique for objectively quantifying humeral head deformity with use of magnetic resonance (MR) imaging and correlates the humeral head deformity with clinical and radiographic outcomes following joint rebalancing surgery. METHODS: Magnetic resonance images of thirty-two children (age, 0.7 to 11.5 years) with neonatal brachial plexus palsy were retrospectively reviewed. Passive shoulder external rotation and Mallet scores were reviewed before joint rebalancing surgery and at a minimum clinical follow-up interval of two years. The humeral head skewness ratio on preoperative and postoperative axial MR images was defined as the ratio of anterior to posterior humeral head area, and this ratio was compared between affected and unaffected shoulders and with the glenoid version angle, posterior subluxation of the humeral head, and clinical parameters before and after surgery with use of paired t tests and Spearman correlation. Intraobserver and interobserver reliability of MR image measurements was determined. RESULTS: Measurements of the skewness ratio on the affected side had moderate to substantial intraobserver reliability (0.53 to 0.72) and substantial interobserver reliability (0.65 to 0.71). Preoperatively, the skewness ratio of the affected humeral head (mean, 0.76; range, 0.54 to 1.03) differed significantly from the ratio in the contralateral shoulder (p<0.05) and was significantly associated with the glenoid version angle (p<0.05) and posterior subluxation of the humeral head (p<0.05). Remodeling of the affected humeral head was observed postoperatively, with a significant improvement in the skewness ratio (p<0.05). However, there were no significant correlations between the preoperative skewness ratio and postoperative clinical outcomes. CONCLUSIONS: Humeral head deformity in neonatal brachial plexus palsy correlated with other measures of glenohumeral dysplasia and could be reliably and objectively quantified on MR imaging with use of the skewness ratio. The humeral head deformity can remodel following joint rebalancing surgery, and such a deformity alone does not preclude a successful outcome after surgical attempts to restore glenohumeral congruity.