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Upper airway volume segmentation analysis using cine MRI findings in children with tracheostomy tubes.

Fricke BL, Abbott MB, Donnelly LF, Dardzinski BJ, Poe SA, Kalra M, Amin RS, Cotton RT - Korean J Radiol (2007 Nov-Dec)

Bottom Line: 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.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.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati OH 45229, USA.

ABSTRACT

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.

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Related in: MedlinePlus

Sagittal cine MR images obtained with a 1.5T scanner in an 11-year-old boy with difficulty in tracheotomy tube decannulation, with the tracheotomy tube capped.A. Gradient-recalled-echo cine image. The line shows the region of interest of the nasopharynx.B. Gradient-recalled-echo cine image. The line shows the region of interest of the hypopharynx.
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Figure 1: Sagittal cine MR images obtained with a 1.5T scanner in an 11-year-old boy with difficulty in tracheotomy tube decannulation, with the tracheotomy tube capped.A. Gradient-recalled-echo cine image. The line shows the region of interest of the nasopharynx.B. Gradient-recalled-echo cine image. The line shows the region of interest of the hypopharynx.

Mentions: A region of interest for volume segmentation was manually selected to evaluate either the nasopharynx or the hypopharynx (Fig. 1). The nasopharynx was defined antero-superiorly by the sphenoid and posterior choanae, posteriorly by the anterior aspect of the cervical vertebrae and the adenoid tonsils, and inferiorly by the soft palate and hard palate. The hypopharynx was defined superiorly by the base of the adenoid tonsils, posteriorly by the posterior pharyngeal wall, inferiorly by a horizontal plane at the level of the hyoid bone, and anteriorly by the posterior aspect of the tongue (Fig. 1). The matrix of intensity data within the region of interest was then analyzed using a k-means clustering algorithm that segments the region of interest using signal intensity for the entire data set (all slices over all time). Three segments of intensity were selected as this yields the most accurate depiction of airway volume as this best represented the anatomy of the patent airway regions (26). The image segment representing patent airway intensity was selected and the airway volume was plotted as a function of time. Numerical characterization of the airway size allowed statistical analysis of airway dynamics and objective comparison of uncapped and capped images.


Upper airway volume segmentation analysis using cine MRI findings in children with tracheostomy tubes.

Fricke BL, Abbott MB, Donnelly LF, Dardzinski BJ, Poe SA, Kalra M, Amin RS, Cotton RT - Korean J Radiol (2007 Nov-Dec)

Sagittal cine MR images obtained with a 1.5T scanner in an 11-year-old boy with difficulty in tracheotomy tube decannulation, with the tracheotomy tube capped.A. Gradient-recalled-echo cine image. The line shows the region of interest of the nasopharynx.B. Gradient-recalled-echo cine image. The line shows the region of interest of the hypopharynx.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2627453&req=5

Figure 1: Sagittal cine MR images obtained with a 1.5T scanner in an 11-year-old boy with difficulty in tracheotomy tube decannulation, with the tracheotomy tube capped.A. Gradient-recalled-echo cine image. The line shows the region of interest of the nasopharynx.B. Gradient-recalled-echo cine image. The line shows the region of interest of the hypopharynx.
Mentions: A region of interest for volume segmentation was manually selected to evaluate either the nasopharynx or the hypopharynx (Fig. 1). The nasopharynx was defined antero-superiorly by the sphenoid and posterior choanae, posteriorly by the anterior aspect of the cervical vertebrae and the adenoid tonsils, and inferiorly by the soft palate and hard palate. The hypopharynx was defined superiorly by the base of the adenoid tonsils, posteriorly by the posterior pharyngeal wall, inferiorly by a horizontal plane at the level of the hyoid bone, and anteriorly by the posterior aspect of the tongue (Fig. 1). The matrix of intensity data within the region of interest was then analyzed using a k-means clustering algorithm that segments the region of interest using signal intensity for the entire data set (all slices over all time). Three segments of intensity were selected as this yields the most accurate depiction of airway volume as this best represented the anatomy of the patent airway regions (26). The image segment representing patent airway intensity was selected and the airway volume was plotted as a function of time. Numerical characterization of the airway size allowed statistical analysis of airway dynamics and objective comparison of uncapped and capped images.

Bottom Line: 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.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.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati OH 45229, USA.

ABSTRACT

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.

Show MeSH
Related in: MedlinePlus