Bradley L. Fricke

Three-dimensional rotational angiography of neurovascular lesions in pediatric patients.

OBJECTIVE In this pictorial essay, we review the 3D rotational angiography (RA) studies of six pediatric patients; in these cases, the information obtained with 3D RA was uniquely beneficial in diagnosis and treatment planning. CONCLUSION Three-dimensional RA is an excellent tool for the evaluation of a number of intracranial lesions in pediatric patients: There is less total radiation exposure from a single rotational run than from CT or a conventional angiography examination that involves more than one view and the study is quick, with data acquisition requiring less than 8 sec and fully rendered 3D reconstructions generated within 180 sec.

Upper Airway Volume Segmentation Analysis Using Cine MRI Findings in Children with Tracheostomy Tubes

Objective The purpose of this study is to evaluate the airway dynamics of the upper airway as depicted on cine MRI in children with tracheotomy tubes during two states of airflow through the upper airway. Materials and Methods Sagittal fast gradient echo cine MR images of the supra-glottic airway were obtained with a 1.5T MRI scanner on seven children with tracheotomy tubes. Two sets of images were obtained with either the tubes capped or uncapped. The findings of the cine MRI were retrospectively reviewed. Volume segmentation of the cine images to compare the airway volume change over time (mean volume, standard deviation, normalized range, and coefficient of variance) was performed for the capped and uncapped tubes in both the nasopharynx and hypopharynx (Signed Rank Test). Results Graphical representation of the airway volume over time demonstrates a qualitative increased fluctuation in patients with the tracheotomy tube capped as compared to uncapped in both the nasopharyngeal and hypopharyngeal regions of interest. In the nasopharynx, the mean airway volume (capped 2.72 mL, uncapped 2.09 mL, p = 0.0313), the airway volume standard deviation (capped 0.42 mL, uncapped 0.20 mL, p = 0.0156), and the airway volume range (capped 2.10 mL, uncapped 1.09 mL, p = 0.0156) were significantly larger in the capped group of patients. In the hypopharynx, the airway volume standard deviation (capped 1.54 mL, uncapped 0.67 mL, p = 0.0156), and the airway volume range (capped 6.44 mL, uncapped 2.93 mL, p = 0.0156) were significantly larger in the capped tubes. The coefficient of variance (capped 0.37, uncapped 0.26, p = 0.0469) and the normalized range (capped 1.52, uncapped 1.09, p = 0.0313) were significantly larger in the capped tubes. Conclusion There is a statistically significant change in airway dynamics in children with tracheotomy tubes when breathing via the airway as compared to breathing via the tracheotomy tube.